panel and scroll_view

.gitmodules

@@ -10,3 +10,6 @@
 [submodule "dependencies/tsqlite"]
 	path = dependencies/tsqlite
 	url = https://timerix.ddns.net/git/Timerix/tsqlite.git
+[submodule "dependencies/tim"]
+	path = dependencies/tim
+	url = https://timerix.ddns.net/git/Timerix/tim.git

.vscode/c_cpp_properties.json

@@ -9,6 +9,8 @@
                 "dependencies/BearSSL/inc",
                 "dependencies/tlibc/include",
                 "dependencies/tlibtoml/include",
+                "dependencies/tsqlite/include",
+                "dependencies/tim/include",
                 "${default}"
             ],
             "cStandard": "c99"

.vscode/launch.json

@@ -2,29 +2,71 @@
     "version": "0.2.0",
     "configurations": [
         {
-            "name": "gdb_debug",
+            "name": "(gdb) Client | Build and debug",
             "type": "cppdbg",
             "request": "launch",
-            "program": "${workspaceFolder}/bin/tcp-chat",
-            "windows": { "program": "${workspaceFolder}/bin/tcp-chat.exe" },
-            // "args": [ "-l" ],
-            "preLaunchTask": "build_exec_dbg",
-            "stopAtEntry": false,
             "cwd": "${workspaceFolder}/bin",
+            "program": "${workspaceFolder}/bin/tcp-chat",
+            "windows": { 
+                "program": "${workspaceFolder}/bin/tcp-chat.exe",
+                "externalConsole": true
+            },
+            "preLaunchTask": "build_exec_dbg",
+
+            "stopAtEntry": false,
             "externalConsole": false,
             "internalConsoleOptions": "neverOpen",
             "MIMode": "gdb",
-            "miDebuggerPath": "gdb",
-            "setupCommands": [
-                {
-                    "text": "-enable-pretty-printing",
-                    "ignoreFailures": true
+            "miDebuggerPath": "gdb"
         },
         {
-                    "text": "-gdb-set disassembly-flavor intel",
-                    "ignoreFailures": true
-                }
-            ]
+            "name": "(gdb) Client | Just debug",
+            "type": "cppdbg",
+            "request": "launch",
+            "cwd": "${workspaceFolder}/bin",
+            "program": "${workspaceFolder}/bin/tcp-chat",
+            "windows": { 
+                "program": "${workspaceFolder}/bin/tcp-chat.exe",
+                "externalConsole": true
+            },
+
+            "stopAtEntry": false,
+            "externalConsole": false,
+            "internalConsoleOptions": "neverOpen",
+            "MIMode": "gdb",
+            "miDebuggerPath": "gdb"
+        },
+
+        {
+            "name": "(gdb) Server | Build and debug",
+            "type": "cppdbg",
+            "request": "launch",
+            "cwd": "${workspaceFolder}/bin",
+            "program": "${workspaceFolder}/bin/tcp-chat",
+            "windows": { "program": "${workspaceFolder}/bin/tcp-chat.exe" },
+            "args": [ "-l" ],
+            "preLaunchTask": "build_exec_dbg",
+
+            "stopAtEntry": false,
+            "externalConsole": false,
+            "internalConsoleOptions": "neverOpen",
+            "MIMode": "gdb",
+            "miDebuggerPath": "gdb"
+        },
+        {
+            "name": "(gdb) Server | Just debug",
+            "type": "cppdbg",
+            "request": "launch",
+            "cwd": "${workspaceFolder}/bin",
+            "program": "${workspaceFolder}/bin/tcp-chat",
+            "windows": { "program": "${workspaceFolder}/bin/tcp-chat.exe" },
+            "args": [ "-l" ],
+
+            "stopAtEntry": false,
+            "externalConsole": false,
+            "internalConsoleOptions": "neverOpen",
+            "MIMode": "gdb",
+            "miDebuggerPath": "gdb"
         }
     ]
 }

dependencies/tim.config

@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+
+# This is a dependency config.
+# You can copy it to another cbuild project to add this lib as dependency.
+
+DEP_WORKING_DIR="$DEPENDENCIES_DIR/tim"
+if [[ "$TASK" = *_dbg ]]; then
+    dep_build_target="build_static_lib_dbg"
+else
+    dep_build_target="build_static_lib"
+fi
+DEP_PRE_BUILD_COMMAND=""
+DEP_BUILD_COMMAND="cbuild $dep_build_target"
+DEP_POST_BUILD_COMMAND=""
+DEP_CLEAN_COMMAND="cbuild clean"
+DEP_DYNAMIC_OUT_FILES=""
+DEP_STATIC_OUT_FILES="bin/tim.a"
+DEP_OTHER_OUT_FILES=""
+PRESERVE_OUT_DIRECTORY_STRUCTURE=false

include/tcp-chat.h

@@ -0,0 +1,135 @@
+#pragma once
+#include "tlibc/errors.h"
+#include "tlibc/time.h"
+#include "tlibc/magic.h"
+
+/// requires tlibc and tlibtoml init
+Result(void) TcpChat_init();
+void TcpChat_deinit();
+
+#define USERNAME_SIZE_MIN 2
+#define USERNAME_SIZE_MAX 31
+#define PASSWORD_SIZE_MIN 8
+#define PASSWORD_SIZE_MAX 31
+#define PASSWORD_HASH_SIZE 32
+#define HOSTADDR_SIZE_MIN 4
+#define HOSTADDR_SIZE_MAX 255
+#define PRIVATE_KEY_BASE64_SIZE_MAX 1724
+#define PUBLIC_KEY_BASE64_SIZE_MAX 699
+#define SERVER_NAME_SIZE_MIN 1
+#define SERVER_NAME_SIZE_MAX 127
+#define SERVER_DESC_SIZE_MAX 1023
+#define CHANNEL_NAME_SIZE_MIN 1
+#define CHANNEL_NAME_SIZE_MAX 127
+#define CHANNEL_DESC_SIZE_MAX 1023
+#define MESSAGE_SIZE_MIN 1
+#define MESSAGE_SIZE_MAX 4000
+#define MESSAGE_BLOCK_COUNT_MAX 50
+
+#define MESSAGE_TIMESTAMP_FMT_SQL "%Y.%m.%d-%H:%M:%f"
+
+//////////////////////////////////////////////////////////////////////////////
+//                                                                          //
+//                                  Logging                                 //
+//                                                                          //
+//////////////////////////////////////////////////////////////////////////////
+
+ErrorCodePage_declare(WINSOCK2);
+ErrorCodePage_declare(TcpChat);
+
+typedef enum TcpChatError {
+    TcpChatError_Unknown,
+    TcpChatError_RejectIncoming,
+} TcpChatError;
+
+typedef enum LogSeverity {
+    LogSeverity_Debug,
+    LogSeverity_Info,
+    LogSeverity_Warn,
+    LogSeverity_Error,
+} LogSeverity;
+
+typedef void (*LogFunction_t)(void* logger, cstr context, LogSeverity severity, cstr msg);
+
+// requires defined LOGGER, LOG_FUNC, LOG_CONTEXT
+#define log(severity, format, ...) { \
+    if(LOG_FUNC) { \
+        char* ___log_msg = sprintf_malloc(format ,##__VA_ARGS__); \
+        LOG_FUNC(LOGGER, LOG_CONTEXT, severity, ___log_msg); \
+        free(___log_msg); \
+    } \
+}
+
+#define logDebug(format, ...) log(LogSeverity_Debug, format ,##__VA_ARGS__)
+#define logInfo(format, ...)  log(LogSeverity_Info,  format ,##__VA_ARGS__)
+#define logWarn(format, ...)  log(LogSeverity_Warn,  format ,##__VA_ARGS__)
+#define logError(format, ...) log(LogSeverity_Error, format ,##__VA_ARGS__)
+
+
+//////////////////////////////////////////////////////////////////////////////
+//                                                                          //
+//                                  Server                                  //
+//                                                                          //
+//////////////////////////////////////////////////////////////////////////////
+typedef struct Server Server;
+
+/// @param config_file_content config in toml format
+/// @param config_file_name to use in error messages
+/// @param logger some shared data for your log function
+/// @param log_func log function that you have to implement
+/// @return 
+Result(Server*) Server_create(str config_file_content, cstr config_file_name,
+    void* logger, LogFunction_t log_func);
+
+void Server_free(Server* server);
+
+Result(void) Server_run(Server* server);
+
+
+//////////////////////////////////////////////////////////////////////////////
+//                                                                          //
+//                                  Client                                  //
+//                                                                          //
+//////////////////////////////////////////////////////////////////////////////
+typedef struct Client Client;
+
+Result(Client*) Client_create(str username, str password);
+void Client_free(Client* client);
+
+/// @return username saved during client initialization
+str Client_getUserName(Client* client);
+
+/// @return AES key calculated from password that can be used to encrypt user data
+Array(u8) Client_getUserDataKey(Client* client);
+
+/// @param server_addr_cstr ip:port
+/// @param server_pk_base64 public key encoded by `RSA_serializePublicKey_base64()`
+Result(void) Client_connect(Client* client, cstr server_addr_cstr, cstr server_pk_base64);
+/// disconnect from current server
+void Client_disconnect(Client* client);
+
+/// @param self connected client
+/// @param out_str heap-allocated string
+Result(void) Client_getServerName(Client* self, str* out_str);
+
+/// @param self connected client
+/// @param out_str heap-allocated string
+Result(void) Client_getServerDescription(Client* self, str* out_str);
+
+/// Create new account on connected server
+Result(void) Client_register(Client* self, i64* out_user_id);
+
+/// Authorize on connected server
+Result(void) Client_login(Client* self, i64* out_user_id, i64* out_landing_channel_id);
+
+/// @param out_timestamp timestamp received from server
+/// @return message id received from server
+Result(i64) Client_sendMessage(Client* self, i64 channel_id, Array(u8) content, DateTime* out_timestamp);
+
+/// Receive a bunch of messages from the server to a client internal buffer
+/// @return number of messages received
+Result(u32) Client_receiveMessageBlock(Client* self, i64 channel_id, i64 first_message_id, u32 messages_count);
+
+/// Read message saved in client internal buffer.
+/// @return number of bytes written in dst_content
+Result(u32) Client_popMessage(Client* self, Array(u8) dst_content, i64* message_id, i64* sender_id, DateTime* timestamp_utc);

include/tcp-chat/client.h

@@ -1,34 +0,0 @@
-#pragma once
-#include "tlibc/errors.h"
-#include "tlibc/string/str.h"
-
-typedef struct Client Client;
-
-Result(Client*) Client_create(str username, str password);
-void Client_free(Client* client);
-
-/// @return username saved during client initialization
-str Client_getUserName(Client* client);
-
-/// @return AES key calculated from password that can be used to encrypt user data
-Array(u8) Client_getUserDataKey(Client* client);
-
-/// @param server_addr_cstr ip:port
-/// @param server_pk_base64 public key encoded by `RSA_serializePublicKey_base64()`
-Result(void) Client_connect(Client* client, cstr server_addr_cstr, cstr server_pk_base64);
-/// disconnect from current server
-void Client_disconnect(Client* client);
-
-/// @param self connected client
-/// @param out_name owned by Client, fetched from server during Client_connect
-Result(void) Client_getServerName(Client* self, str* out_name);
-
-/// @param self connected client
-/// @param out_name owned by Client, fetched from server during Client_connect
-Result(void) Client_getServerDescription(Client* self, str* out_desc);
-
-/// Create new account on connected server
-Result(void) Client_register(Client* self, u64* out_user_id);
-
-/// Authorize on connected server
-Result(void) Client_login(Client* self, u64* out_user_id, u64* out_landing_channel_id);

include/tcp-chat/common_constants.h

@@ -1,21 +0,0 @@
-#pragma once
-#include "tlibc/std.h"
-
-#define USERNAME_SIZE_MIN 2
-#define USERNAME_SIZE_MAX 31
-#define PASSWORD_SIZE_MIN 8
-#define PASSWORD_SIZE_MAX 31
-#define PASSWORD_HASH_SIZE 32
-#define HOSTADDR_SIZE_MIN 4
-#define HOSTADDR_SIZE_MAX 255
-#define PRIVATE_KEY_BASE64_SIZE_MAX 1724
-#define PUBLIC_KEY_BASE64_SIZE_MAX 699
-#define SERVER_NAME_SIZE_MIN 1
-#define SERVER_NAME_SIZE_MAX 127
-#define SERVER_DESC_SIZE_MAX 1023
-#define CHANNEL_NAME_SIZE_MIN 1
-#define CHANNEL_NAME_SIZE_MAX 127
-#define CHANNEL_DESC_SIZE_MAX 1023
-#define MESSAGE_SIZE_MIN 1
-#define MESSAGE_SIZE_MAX 4000
-#define MESSAGE_BLOCK_SIZE (64*1024)

include/tcp-chat/log.h

@@ -1,28 +0,0 @@
-#pragma once
-#include <stdio.h>
-#include "tlibc/std.h"
-#include "tlibc/string/cstr.h"
-
-typedef enum LogSeverity {
-    LogSeverity_Debug,
-    LogSeverity_Info,
-    LogSeverity_Warn,
-    LogSeverity_Error,
-} LogSeverity;
-
-typedef void (*LogFunction_t)(void* logger, cstr context, LogSeverity severity, cstr msg);
-
-
-// requires defined LOGGER, LOG_FUNC, LOG_CONTEXT
-#define log(severity, format, ...) { \
-    if(LOG_FUNC) { \
-        char* ___log_msg = sprintf_malloc(format ,##__VA_ARGS__); \
-        LOG_FUNC(LOGGER, LOG_CONTEXT, severity, ___log_msg); \
-        free(___log_msg); \
-    } \
-}
-
-#define logDebug(format, ...) log(LogSeverity_Debug, format ,##__VA_ARGS__)
-#define logInfo(format, ...)  log(LogSeverity_Info,  format ,##__VA_ARGS__)
-#define logWarn(format, ...)  log(LogSeverity_Warn,  format ,##__VA_ARGS__)
-#define logError(format, ...) log(LogSeverity_Error, format ,##__VA_ARGS__)

include/tcp-chat/server.h

@@ -1,18 +0,0 @@
-#pragma once
-#include "tlibc/errors.h"
-#include "tlibc/string/str.h"
-#include "tcp-chat/log.h"
-
-typedef struct Server Server;
-
-/// @param config_file_content config in toml format
-/// @param config_file_name to use in error messages
-/// @param logger some shared data for your log function
-/// @param log_func log function that you have to implement
-/// @return 
-Result(Server*) Server_create(str config_file_content, cstr config_file_name,
-    void* logger, LogFunction_t log_func);
-
-void Server_free(Server* server);
-
-Result(void) Server_run(Server* server);

include/tcp-chat/tcp-chat.h

@@ -1,14 +0,0 @@
-#pragma once
-#include "tlibc/errors.h"
-
-/// requires tlibc and tlibtoml init
-Result(void) TcpChat_init();
-void TcpChat_deinit();
-
-ErrorCodePage_declare(WINSOCK2);
-ErrorCodePage_declare(TcpChat);
-
-typedef enum TcpChatError {
-    TcpChatError_Unknown,
-    TcpChatError_RejectIncoming,
-} TcpChatError;

project.config

@@ -24,7 +24,7 @@ SRC_CPP="$(find src -name '*.cpp')"
 # See cbuild/example_dependency_configs
 DEPENDENCY_CONFIGS_DIR='dependencies'
 # List of dependency config files in DEPENDENCY_CONFIGS_DIR separated by space.
-ENABLED_DEPENDENCIES='bearssl tlibc tlibtoml tsqlite'
+ENABLED_DEPENDENCIES='bearssl tlibc tlibtoml tsqlite tim'
 
 # OBJDIR structure:
 #  ├── objects/      - Compiled object files. Cleans on each call of build task
@@ -38,7 +38,9 @@ STATIC_LIB_FILE="$PROJECT.a"
 INCLUDE="-Isrc -Iinclude 
     -I$DEPENDENCIES_DIR/BearSSL/inc 
     -I$DEPENDENCIES_DIR/tlibc/include 
-    -I$DEPENDENCIES_DIR/tlibtoml/include"
+    -I$DEPENDENCIES_DIR/tlibtoml/include
+    -I$DEPENDENCIES_DIR/tsqlite/include
+    -I$DEPENDENCIES_DIR/tim/include"
 
 # OS-specific options
 case "$OS" in
@@ -46,7 +48,7 @@ case "$OS" in
         EXEC_FILE="$PROJECT.exe"
         SHARED_LIB_FILE="$PROJECT.dll"
         INCLUDE="$INCLUDE "
-        LINKER_LIBS="-static -lpthread -lws2_32 -lsqlite3"
+        LINKER_LIBS="-static -lpthread -lws2_32 -luuid -lsqlite3"
         ;;
     LINUX)
         EXEC_FILE="$PROJECT"

src/cli/ClientCLI/ClientCLI.c

@@ -1,438 +1,66 @@
+#include "ClientCLI.h"
 #include "tlibc/filesystem.h"
 #include "tlibc/term.h"
-#include "tcp-chat/common_constants.h"
-#include "cli/ClientCLI/ClientCLI.h"
 #include "network/tcp-chat-protocol/v1.h"
-
-static const str greeting_art = STR(
-    "   ^,,^                           ╱|\n"
-    "  ( •·•)   Meum!                (o.o`7\n"
-    "  / ` |                 Meum...  |`˜ \\\n"
-    "\\(_,J J                          L l`,)/\n"
-);
-    
-static const str farewell_art = STR(
-    "   ^,,^                           ╱|\n"
-    "  ( -.-)                        (>,<`7\n"
-    "  / ` |        Goodbye!          |`˜ \\\n"
-    "\\(_,J J                          L l`,)/\n"
-);
-
-
-#define is_alias(LITERAL) str_equals(command, STR(LITERAL))
-
-static Result(void) ClientCLI_askUserNameAndPassword(str* username_out, str* password_out);
-static Result(void) ClientCLI_execCommand(ClientCLI* self, str command, bool* stop);
-static Result(void) ClientCLI_openUserDB(ClientCLI* self);
-static Result(ServerInfo*) ClientCLI_saveServerInfo(ClientCLI* self, 
-        str addr, str pk_base64, str name, str desc);
-static Result(ServerInfo*) ClientCLI_joinNewServer(ClientCLI* self);
-static Result(ServerInfo*) ClientCLI_selectServerFromCache(ClientCLI* self);
-static Result(void) ClientCLI_showServerInfo(ClientCLI* self, ServerInfo* server);
-static Result(void) ClientCLI_register(ClientCLI* self);
-static Result(void) ClientCLI_login(ClientCLI* self);
+#include <assert.h>
 
 void ClientCLI_destroy(ClientCLI* self){
     if(!self)
         return;
     
     Client_free(self->client);
-
-    idb_close(self->db);
-    List_ServerInfo_destroy(&self->servers.list);
-    HashMap_destroy(&self->servers.addr_id_map);
+    ClientQueries_free(self->queries);
+    tsqlite_connection_close(self->db);
+    List_SavedServer_destroyWithElements(&self->saved_servers, SavedServer_destroy);
 }
+
 void ClientCLI_construct(ClientCLI* self){
     zeroStruct(self);
+
+    self->style.common = (TimStyle){ 
+        .brd = Color256_LightGray, 
+        .bg = Color256_NavyBlue, 
+        .fg = Color256_LightGray 
+    };
+    self->style.focused = (TimStyle){ 
+        .brd = Color256_White, 
+        .bg = Color256_DeepSkyBlue, 
+        .fg = Color256_White 
+    };
+    self->style.error = (TimStyle){ 
+        .brd = Color256_LightGray, 
+        .bg = Color256_DarkRed, 
+        .fg = Color256_White 
+    };
+
+    self->saved_servers = List_SavedServer_alloc(0);
 }
 
-Result(void) ClientCLI_run(ClientCLI* self) {
-    Deferral(16);
+void ClientCLI_run(ClientCLI* self) {
+    Deferral(32);
 
-    try_void(term_init());
-    term_clear();
-    printf(FMT_str"\n", greeting_art.len, greeting_art.data);
+    StartScreenContext start_screen_ctx;
+    StartScreenContext_construct(&start_screen_ctx, self);
+    Defer(StartScreenContext_destroy(&start_screen_ctx));
+    MainScreenContext main_screen_ctx;
+    MainScreenContext_construct(&main_screen_ctx, self);
+    Defer(MainScreenContext_destroy(&main_screen_ctx));
 
-    // create Client
-    str username = str_null, password = str_null;
-    try_void(ClientCLI_askUserNameAndPassword(&username, &password));
-    Defer(
-        str_destroy(username);
-        str_destroy(password);
-    );
-    Client_free(self->client);
-    try(self->client, p, Client_create(username, password));
-    memset(password.data, 0, password.len);
-
-    // init db
-    try_void(ClientCLI_openUserDB(self));
-
-    char input_buf[1024];
-    str command_input = str_null;
-    bool stop = false;
-    while(!stop){
-        sleepMsec(50);
-        printf("> ");
-        try_void(term_readLine(input_buf, sizeof(input_buf)));
-        
-        command_input = str_from_cstr(input_buf);
-        str_trim(&command_input, true);
-        if(command_input.len == 0)
-            continue;
-        
-        ResultVar(void) com_result = ClientCLI_execCommand(self, command_input, &stop);
-        if(com_result.error){
-            Error_addCallPos(com_result.error, ErrorCallPos_here());
-            str e_str = Error_toStr(com_result.error);
-            printf("\n"FMT_str"\n", e_str.len, e_str.data);
-            str_destroy(e_str);
-            Error_free(com_result.error);
+    while(tim_run(FPS)){
+        switch(self->state){
+            case ClientCLIState_Exit:
+                Return;
+            default:
+                assert(false && "invalid ClientCLI state");
+                break;
+            case ClientCLIState_StartScreen:
+                start_screen(&start_screen_ctx);
+                break;
+            case ClientCLIState_MainScreen:
+                main_screen(&main_screen_ctx);
+                break;
         }
     }
 
-    Return RESULT_VOID;
-}
-
-static Result(void) ClientCLI_askUserNameAndPassword(str* username_out, str* password_out){
-    Deferral(8);
-    bool success = false;
-
-    // ask username
-    Array(char) username_buf = Array_char_alloc(128);
-    Defer(if(!success) Array_char_destroy(&username_buf));
-    str username = str_null;
-    while(true) {
-        printf("username: ");
-        try_void(term_readLine(username_buf.data, username_buf.len));
-        username = str_from_cstr(username_buf.data);
-        str_trim(&username, true);
-        str name_error_str = validateUsername_str(username);
-        if(name_error_str.data){
-            printf("ERROR: "FMT_str"\n", 
-                name_error_str.len, name_error_str.data);
-        }
-        else break;
-    }
-
-    // ask password
-    Array(char) password_buf = Array_char_alloc(128);
-    Defer(if(!success) Array_char_destroy(&password_buf));
-    str password = str_null;
-    while(true) {
-        printf("password: ");
-        // TODO: hide password
-        try_void(term_readLineHidden(password_buf.data, password_buf.len));
-        password = str_from_cstr(password_buf.data);
-        str_trim(&password, true);
-        if(password.len < PASSWORD_SIZE_MIN || password.len > PASSWORD_SIZE_MAX){
-            printf("ERROR: password length (in bytes) must be >= %i and <= %i\n", 
-                PASSWORD_SIZE_MIN, PASSWORD_SIZE_MAX);
-        }
-        else break;
-    }
-
-    *username_out = username;
-    *password_out = password;
-    success = true;
-    Return RESULT_VOID;
-}
-
-static Result(void) ClientCLI_execCommand(ClientCLI* self, str command, bool* stop){
-    Deferral(64);
-
-    if(is_alias("q") || is_alias("quit") || is_alias("exit")){
-        printf(FMT_str"\n", farewell_art.len, farewell_art.data);
-        *stop = true;
-    }
-    else if(is_alias("clear")){
-        term_clear();
-    }
-    else if(is_alias("h") || is_alias("help")){
-        printf(
-           "COMMANDS:\n"
-           "Without connection:\n"
-           "    h, help             Show this message.\n"
-           "    q, quit, exit       Close the program.\n"
-           "    clear               Clear the screen.\n"
-           "Connection:\n"
-           "    j, join             Join a new server and select it.\n"
-           "    s, select           Select a server you joined before.\n"
-           "After connection:\n"
-           "    r, register         Create account on selected server\n"
-           "    l, login            Authorize on selected server\n"
-           "Authorized:\n"
-        );
-    }
-    else if (is_alias("j") || is_alias("join")){
-        // ask address and key, connect to server
-        try_void(ClientCLI_joinNewServer(self));
-    }
-    else if(is_alias("s") || is_alias("select")){
-        // show scrollable list of servers, get selected one
-        try_void(ClientCLI_selectServerFromCache(self));
-    }
-    else if(is_alias("r") || is_alias("register")){
-        try_void(ClientCLI_register(self));
-    }
-    else if(is_alias("l") || is_alias("login")){
-        try_void(ClientCLI_login(self));
-        // TODO: call Client_runIO(): 
-        //      function with infinite loop which sends and receives messages
-        //      with navigation across server channels
-    }
-    else {
-        printf("ERROR: unknown command.\n"
-            "Use 'h' to see list of avaliable commands\n");
-    }
-
-    Return RESULT_VOID;
-}
-
-static Result(void) ClientCLI_joinNewServer(ClientCLI* self){
-    Deferral(8);
-
-    // ask server address
-    printf("Enter server address (ip:port):\n");
-    char server_addr_cstr[HOSTADDR_SIZE_MAX + 1];
-    try_void(term_readLine(server_addr_cstr, sizeof(server_addr_cstr)));
-    str server_addr_str = str_from_cstr(server_addr_cstr);
-    str_trim(&server_addr_str, true);
-
-    // ask server public key
-    printf("Enter server public key (RSA-Public-<SIZE>:<DATA>):\n");
-    char server_pk_cstr[PUBLIC_KEY_BASE64_SIZE_MAX + 1];
-    try_void(term_readLine(server_pk_cstr, sizeof(server_pk_cstr)));
-    str server_pk_str = str_from_cstr(server_pk_cstr);
-    str_trim(&server_pk_str, true);
-    
-    printf("Connecting to server...\n");
-    try_void(Client_connect(self->client, server_addr_cstr, server_pk_cstr));
-    printf("Connection established\n");
-    
-    str server_name = str_null;
-    str server_description = str_null;
-    try_void(Client_getServerName(self->client, &server_name));
-    try_void(Client_getServerDescription(self->client, &server_description));
-    try(ServerInfo* server, p, ClientCLI_saveServerInfo(self,
-        server_addr_str, server_pk_str,
-        server_name, server_description));
-
-    try_void(ClientCLI_showServerInfo(self, server));
-
-    Return RESULT_VOID;
-}
-
-static Result(void) ClientCLI_selectServerFromCache(ClientCLI* self){
-    Deferral(8);
-
-    // Lock table until this function returns.
-    // It may not change any data in table, but it uses associated cache structures.
-    idb_lockTable(self->servers.table);
-    Defer(idb_unlockTable(self->servers.table));
-
-    u32 servers_count = self->servers.list.len;
-    if(servers_count == 0){
-        printf("No servers found in cache\n");
-        Return RESULT_VOID;
-    }
-
-    for(u32 id = 0; id < servers_count; id++){
-        ServerInfo* server = self->servers.list.data + id;
-        printf("[%02u] "FMT_str" "FMT_str"\n", 
-            id, server->address_len, server->address, server->name_len, server->name);
-    }
-
-    char buf[32];
-    u32 id = -1;
-    while(true) {
-        printf("Type 'q' to cancel\n");
-        printf("Select server (number): ");
-        try_void(term_readLine(buf, sizeof(buf)));
-        str input_line = str_from_cstr(buf);
-        str_trim(&input_line, true);
-        if(str_equals(input_line, STR("q"))){
-            Return RESULT_VOID;
-        }
-        if(sscanf(buf, FMT_u32, &id) != 1){
-            printf("ERROR: not a number\n");
-        }
-        else if(id >= servers_count){
-            printf("ERROR: not a server number: %u\n", id);
-        }
-        else break;
-    }
-    ServerInfo* server = self->servers.list.data + id;
-
-    printf("Connecting to '"FMT_str"'...\n", server->address_len, server->address);
-    try_void(Client_connect(self->client, server->address, server->pk_base64));
-    printf("Connection established\n");
-    
-    bool server_info_changed = false;
-    // update cached server name
-    str name = str_null;
-    try_void(Client_getServerName(self->client, &name));
-    if(!str_equals(name, str_construct(server->name, server->name_len, true))){
-        server_info_changed = true;
-        if(name.len > SERVER_NAME_SIZE_MAX)
-            name.len = SERVER_NAME_SIZE_MAX;
-        server->name_len = name.len;
-        memcpy(server->name, name.data, server->name_len);
-    }
-    // update cached server description
-    str desc = str_null;
-    try_void(Client_getServerDescription(self->client, &desc));
-    if(!str_equals(desc, str_construct(server->desc, server->desc_len, true))){
-        server_info_changed = true;
-        if(desc.len > SERVER_DESC_SIZE_MAX)
-            desc.len = SERVER_DESC_SIZE_MAX;
-        server->desc_len = desc.len;
-        memcpy(server->desc, desc.data, server->desc_len);
-    }
-    if(server_info_changed){
-        try_void(idb_updateRow(self->servers.table, id, server, false));
-    }
-
-    try_void(ClientCLI_showServerInfo(self, server));
-
-    Return RESULT_VOID;
-}
-
-static Result(void) ClientCLI_showServerInfo(ClientCLI* self, ServerInfo* server){
-    Deferral(8);
-    (void)self;
-
-    printf("Server Name:  "FMT_str"\n", server->name_len, server->name);
-    printf("Host Address: "FMT_str"\n", server->address_len, server->address);
-    printf("Description:\n"FMT_str"\n\n", server->desc_len, server->desc);
-    printf("Public Key:\n" FMT_str"\n\n", server->pk_base64_len, server->pk_base64);
-    printf("Type 'register' if you don't have an account on the server.\n");
-    printf("Type 'login' to authorize on the server.\n");
-
-    Return RESULT_VOID;
-}
-
-static Result(void) ClientCLI_openUserDB(ClientCLI* self){
-    Deferral(8);
-
-    str username = Client_getUserName(self->client);
-    Array(u8) user_data_key = Client_getUserDataKey(self->client);
-    str user_db_dir = str_from_cstr(strcat_malloc("client-db", path_seps, username.data));
-    Defer(free(user_db_dir.data));
-    try(self->db, p, idb_open(user_db_dir, user_data_key));
-
-    // Lock DB until this function returns.
-    idb_lockDB(self->db);
-    Defer(idb_unlockDB(self->db));
-
-    // Load servers table
-    try(self->servers.table, p,
-        idb_getOrCreateTable(self->db, str_null, STR("servers"), sizeof(ServerInfo), false)
-    );
-    
-    // Lock table until this function returns.
-    idb_lockTable(self->servers.table);
-    Defer(idb_unlockTable(self->servers.table));
-
-    // load whole servers table to list
-    try_void(
-        idb_createListFromTable(self->servers.table, (void*)&self->servers.list, false)
-    );
-
-    // build address-id map
-    try(u64 servers_count, u,
-        idb_getRowCount(self->servers.table, false)
-    );
-    HashMap_construct(&self->servers.addr_id_map, u64, NULL);
-    for(u64 id = 0; id < servers_count; id++){
-        ServerInfo* server = self->servers.list.data + id;
-        str key = str_construct(server->address, server->address_len, true);
-        if(!HashMap_tryPush(&self->servers.addr_id_map, key, &id)){
-            Return RESULT_ERROR_FMT(
-                "duplicate server address '"FMT_str"'", 
-                key.len, key.data);
-        }
-    }
-
-    Return RESULT_VOID;
-}
-
-static Result(ServerInfo*) ClientCLI_saveServerInfo(ClientCLI* self, 
-        str addr, str pk_base64, str name, str desc){
-    Deferral(8);
-
-    // create new server info
-    ServerInfo server;
-    zeroStruct(&server);
-    // address
-    if(addr.len > HOSTADDR_SIZE_MAX)
-        addr.len = HOSTADDR_SIZE_MAX;
-    server.address_len = addr.len;
-    memcpy(server.address, addr.data, server.address_len);
-    // public key
-    if(pk_base64.len > PUBLIC_KEY_BASE64_SIZE_MAX)
-        pk_base64.len = PUBLIC_KEY_BASE64_SIZE_MAX;
-    server.pk_base64_len = pk_base64.len;
-    memcpy(server.pk_base64, pk_base64.data, server.pk_base64_len);
-    // name
-    if(name.len > SERVER_NAME_SIZE_MAX)
-        name.len = SERVER_NAME_SIZE_MAX;
-    server.name_len = name.len;
-    memcpy(server.name, name.data, server.name_len);
-    // description
-    if(desc.len > SERVER_DESC_SIZE_MAX)
-        desc.len = SERVER_DESC_SIZE_MAX;
-    server.desc_len = desc.len;
-    memcpy(server.desc, desc.data, server.desc_len);
-    
-    // Lock table until this function returns.
-    // It may not change any data in table, but it uses associated cache structures.
-    idb_lockTable(self->servers.table);
-    Defer(idb_unlockTable(self->servers.table));
-
-    // try find server id in cache
-    ServerInfo* cached_row_ptr = NULL;
-    u64* id_ptr = NULL;
-    id_ptr = HashMap_tryGetPtr(&self->servers.addr_id_map, addr);
-    if(id_ptr){
-        // update existing server
-        u64 id = *id_ptr;
-        try_void(idb_updateRow(self->servers.table, id, &server, false));
-        try_assert(id < self->servers.list.len);
-        cached_row_ptr = self->servers.list.data + id;
-        memcpy(cached_row_ptr, &server, sizeof(ServerInfo));
-    }
-    else {
-        // push new server
-        try(u64 id, u, idb_pushRow(self->servers.table, &server, false));
-        try_assert(id == self->servers.list.len);
-        List_ServerInfo_pushMany(&self->servers.list, &server, 1);
-        cached_row_ptr = self->servers.list.data + id;
-        try_assert(HashMap_tryPush(&self->servers.addr_id_map, addr, &id));
-    }
-
-    Return RESULT_VALUE(p, cached_row_ptr);
-}
-
-static Result(void) ClientCLI_register(ClientCLI* self){
-    Deferral(8);
-
-    u64 user_id = 0;
-    try_void(Client_register(self->client, &user_id));
-    printf("Registered successfully\n");
-    printf("user_id: "FMT_u64"\n", user_id);
-    // TODO: use user_id somewhere
-    
-    Return RESULT_VOID;
-}
-
-static Result(void) ClientCLI_login(ClientCLI* self){
-    Deferral(8);
-
-    u64 user_id = 0, landing_channel_id = 0;
-    try_void(Client_login(self->client, &user_id, &landing_channel_id));
-    printf("Authorized successfully\n");
-    printf("user_id: "FMT_u64", landing_channel_id: "FMT_u64"\n", user_id, landing_channel_id);
-    // TODO: use user_id, landing_channel_id somewhere
-
-    Return RESULT_VOID;
+    Return;
 }

src/cli/ClientCLI/ClientCLI.h

@@ -1,23 +1,95 @@
 #pragma once
 #include <pthread.h>
+#include "tcp-chat.h"
 #include "tlibc/collections/HashMap.h"
 #include "tlibc/collections/List.h"
-#include "tcp-chat/client.h"
-#include "db/idb.h"
-#include "db/tables.h"
+#include "db/client_db.h"
+#include "tim.h"
 
-List_declare(ServerInfo);
+#define FPS 30
+
+typedef enum ClientCLIState {
+    ClientCLIState_StartScreen,
+    ClientCLIState_Exit,
+    ClientCLIState_MainScreen,
+    ClientCLIState_ServerChannels,
+    ClientCLIState_ChannelChat,
+} ClientCLIState;
 
 typedef struct ClientCLI {
-    Client* client;
-    IncrementalDB* db;
+    ClientCLIState state;
     struct {
-        Table* table;
-        List(ServerInfo) list;  // index is id
-        HashMap(u64) addr_id_map; // key is server address
-    } servers;
+        TimStyle common;
+        TimStyle focused;
+        TimStyle error;
+    } style;
+    Client* client;
+    tsqlite_connection* db;
+    ClientQueries* queries;
+    List(SavedServer) saved_servers;
 } ClientCLI;
 
 void ClientCLI_construct(ClientCLI* self);
 void ClientCLI_destroy(ClientCLI* self);
-Result(void) ClientCLI_run(ClientCLI* self);
+void ClientCLI_run(ClientCLI* self);
+
+
+enum {
+    Color256_Black = 0x10,
+    Color256_MidGray = 0xf8,
+    Color256_LightGray = 0xfb,
+    Color256_White = 0xe7,
+    Color256_NavyBlue = 0x11,
+    Color256_DeepSkyBlue = 0x18,
+    Color256_DarkRed = 0x58,
+};
+
+typedef struct TextInputState {
+    TimEditState edit;
+    cstr label;
+    struct {
+        TimStyle common;
+        TimStyle focused;
+    } style;
+    TimKey result_key;
+} TextInputState;
+
+void TextInputState_construct(TextInputState* ctx, cstr label, 
+    Array(char) buf, NULLABLE(cstr) initial_value, bool masked, 
+    TimStyle common, TimStyle focused);
+
+/// tim_edit with tim_label over its upper border. 
+void text_input(TextInputState* ctx, i32 x, i32 y, i32 w, TimStyle style);
+
+void TimPanelItem_fromTextInputState(TimPanelItem* item, TextInputState* input);
+
+/// Intended to use in TimPanelItem
+/// @param data TextInputState*
+void draw_item_text_input(void* data, TimRect place, bool is_selected);
+
+
+List_declare(TimPanelItem);
+
+typedef struct StartScreenContext {
+    ClientCLI* client;
+    char* err_msg; // heap only
+    TextInputState input_username;
+    TextInputState input_password;
+    TimPanel central_panel;
+    TimPanel central_buttons_panel;
+} StartScreenContext;
+
+void StartScreenContext_construct(StartScreenContext* ctx, ClientCLI* client);
+void StartScreenContext_destroy(StartScreenContext* ctx);
+void start_screen(StartScreenContext* ctx);
+
+
+typedef struct MainScreenContext {
+    ClientCLI* client;
+    TimPanel central_panel;
+    TimScrollView central_scroll_view;
+} MainScreenContext;
+
+void MainScreenContext_construct(MainScreenContext* ctx, ClientCLI* client);
+void MainScreenContext_destroy(MainScreenContext* ctx);
+void main_screen(MainScreenContext* ctx);

src/cli/ClientCLI/db/SavedServer.c

@@ -0,0 +1,98 @@
+#include "client_db_internal.h"
+
+void SavedServer_destroy(SavedServer* self){
+    if(!self)
+        return;
+    str_destroy(self->address);
+    str_destroy(self->pk_base64);
+    str_destroy(self->name);
+    str_destroy(self->description);
+}
+
+Result(bool) SavedServer_exists(ClientQueries* q, str address){
+    Deferral(4);
+
+    tsqlite_statement* st = q->servers.exists;
+    Defer(tsqlite_statement_reset(st));
+    try_void(tsqlite_statement_bind_str(st, "$address", address, NULL));
+
+    try(bool has_result, i, tsqlite_statement_step(st));
+
+    Return RESULT_VALUE(i, has_result);
+}
+
+Result(bool) SavedServer_comparePublicKey(ClientQueries* q, str address, str pk_base64){
+    Deferral(4);
+
+    tsqlite_statement* st = q->servers.compare_pk;
+    Defer(tsqlite_statement_reset(st));
+    try_void(tsqlite_statement_bind_str(st, "$address", address, NULL));
+    try_void(tsqlite_statement_bind_str(st, "$pk_base64", pk_base64, NULL));
+
+    try(bool has_result, i, tsqlite_statement_step(st));
+
+    Return RESULT_VALUE(i, has_result);
+}
+
+Result(void) SavedServer_createOrUpdate(ClientQueries* q, SavedServer* server){
+    Deferral(4);
+    try_assert(server->address.len >= HOSTADDR_SIZE_MIN && server->address.len <= HOSTADDR_SIZE_MAX);
+    try_assert(server->pk_base64.len > 0 && server->pk_base64.len <= PUBLIC_KEY_BASE64_SIZE_MAX);
+    try_assert(server->name.len >= SERVER_NAME_SIZE_MIN && server->name.len <= SERVER_NAME_SIZE_MAX);
+    try_assert(server->description.len <= SERVER_DESC_SIZE_MAX);
+
+    try(bool server_exists, i, SavedServer_exists(q, server->address));
+    tsqlite_statement* st = NULL;
+    Defer(tsqlite_statement_reset(st));
+    if(server_exists){
+        st = q->servers.update;
+        try(bool pk_matches, i, SavedServer_comparePublicKey(q, server->address, server->pk_base64));
+        if(!pk_matches){
+            Return RESULT_ERROR_FMT(
+                "trying to update server '"FMT_str"' but public keys don't match", 
+                str_unwrap(server->address));
+        }
+    }
+    else {
+        st = q->servers.insert;
+        try_void(tsqlite_statement_bind_str(st, "$pk_base64", server->pk_base64, NULL));
+    }
+    try_void(tsqlite_statement_bind_str(st, "$address", server->address, NULL));
+    try_void(tsqlite_statement_bind_str(st, "$name", server->name, NULL));
+    try_void(tsqlite_statement_bind_str(st, "$description", server->description, NULL));
+    try_void(tsqlite_statement_step(st));
+
+    Return RESULT_VALUE(i, !server_exists);
+}
+
+Result(void) SavedServer_getAll(ClientQueries* q, List(SavedServer)* dst_list){
+    Deferral(4);
+
+    tsqlite_statement* st = q->servers.get_all;
+    Defer(tsqlite_statement_reset(st));
+    
+    SavedServer server = SavedServer_construct(str_null, str_null, str_null, str_null);
+    str tmp_str = str_null;
+    while(true){
+        try(bool has_result, i, tsqlite_statement_step(st));
+        if(!has_result)
+            break;
+        
+        // address
+        try_void(tsqlite_statement_getResult_str(st, &tmp_str));
+        server.address = str_copy(tmp_str);
+        // pk_base64
+        try_void(tsqlite_statement_getResult_str(st, &tmp_str));
+        server.pk_base64 = str_copy(tmp_str);
+        // name
+        try_void(tsqlite_statement_getResult_str(st, &tmp_str));
+        server.name = str_copy(tmp_str);
+        // description
+        try_void(tsqlite_statement_getResult_str(st, &tmp_str));
+        server.description = str_copy(tmp_str);
+        
+        List_SavedServer_pushMany(dst_list, &server, 1);
+    }
+
+    Return RESULT_VOID;
+}

src/cli/ClientCLI/db/client_db.c

@@ -0,0 +1,81 @@
+#include "client_db_internal.h"
+#include "tlibc/filesystem.h"
+
+Result(tsqlite_connection* db) ClientDatabase_open(cstr file_path){
+    Deferral(64);
+    
+    try_void(dir_createParent(file_path));
+    try(tsqlite_connection* db, p, tsqlite_connection_open(file_path));
+    bool success = false;
+    Defer(if(!success) tsqlite_connection_close(db));
+    
+    ///////////////////////////////////////////////////////////////////////////
+    //                                SERVERS                                //
+    ///////////////////////////////////////////////////////////////////////////
+    try(tsqlite_statement* create_table_servers, p, tsqlite_statement_compile(db, STR(
+        "CREATE TABLE IF NOT EXISTS servers (\n"
+        "   address VARCHAR PRIMARY KEY,\n"
+        "   pk_base64 VARCHAR NOT NULL,\n"
+        "   name VARCHAR NOT NULL,\n"
+        "   description VARCHAR NOT NULL\n"
+        ");"
+    )));
+    Defer(tsqlite_statement_free(create_table_servers));
+    try_void(tsqlite_statement_step(create_table_servers));
+    
+    success = true;
+    Return RESULT_VALUE(p, db);
+}
+
+
+void ClientQueries_free(ClientQueries* q){
+    if(!q)
+        return;
+
+    tsqlite_statement_free(q->servers.insert);
+    tsqlite_statement_free(q->servers.update);
+    tsqlite_statement_free(q->servers.exists);
+    tsqlite_statement_free(q->servers.compare_pk);
+    tsqlite_statement_free(q->servers.get_all);
+
+    free(q);
+}
+
+Result(ClientQueries*) ClientQueries_compile(tsqlite_connection* db){
+    Deferral(4);
+    
+    ClientQueries* q = (ClientQueries*)malloc(sizeof(*q));
+    zeroStruct(q);
+    bool success = false;
+    Defer(if(!success) ClientQueries_free(q));
+
+    ///////////////////////////////////////////////////////////////////////////
+    //                                SERVERS                                //
+    ///////////////////////////////////////////////////////////////////////////
+    try(q->servers.insert, p, tsqlite_statement_compile(db, STR(
+        "INSERT INTO\n"
+        "servers (address, pk_base64, name, description)\n"
+        "VALUES ($address, $pk_base64, $name, $description);"
+    )));
+    
+    try(q->servers.update, p, tsqlite_statement_compile(db, STR(
+        "UPDATE servers\n"
+        "SET name = $name, description = $description\n"
+        "WHERE address = $address;"
+    )));
+
+    try(q->servers.exists, p, tsqlite_statement_compile(db, STR(
+        "SELECT 1 FROM servers WHERE address = $address;"
+    )));
+    
+    try(q->servers.compare_pk, p, tsqlite_statement_compile(db, STR(
+        "SELECT 1 FROM servers WHERE address = $address AND pk_base64 = $pk_base64;"
+    )));
+
+    try(q->servers.get_all, p, tsqlite_statement_compile(db, STR(
+        "SELECT * FROM servers;"
+    )));
+
+    success = true;
+    Return RESULT_VALUE(p, q);
+}

src/cli/ClientCLI/db/client_db.h

@@ -0,0 +1,38 @@
+#pragma once
+#include "tcp-chat.h"
+#include "tsqlite.h"
+#include "network/tcp-chat-protocol/v1.h"
+#include "tlibc/collections/List.h"
+
+/// @brief open DB and create tables
+Result(tsqlite_connection* db) ClientDatabase_open(cstr file_path);
+
+typedef struct ClientQueries ClientQueries;
+Result(ClientQueries*) ClientQueries_compile(tsqlite_connection* db);
+void ClientQueries_free(ClientQueries* self);
+
+
+typedef struct SavedServer {
+    str address;
+    str pk_base64;
+    str name;
+    str description;
+} SavedServer;
+
+List_declare(SavedServer);
+
+#define SavedServer_construct(ADDR, PK, NAME, DESC) ((SavedServer){ \
+    .address = ADDR, .pk_base64 = PK, .name = NAME, .description = DESC })
+
+void SavedServer_destroy(SavedServer* self);
+
+/// @return true if new row was created
+Result(bool) SavedServer_createOrUpdate(ClientQueries* q, SavedServer* server);
+
+/// @param dst_list there SavedServer values are pushed
+Result(void) SavedServer_getAll(ClientQueries* q, List(SavedServer)* dst_list);
+
+Result(bool) SavedServer_exists(ClientQueries* q, str address);
+
+/// @return true if provided key and saved key match
+Result(bool) SavedServer_comparePublicKey(ClientQueries* q, str address, str pk_base64);

src/cli/ClientCLI/db/client_db_internal.h

@@ -0,0 +1,17 @@
+#pragma once
+#include "client_db.h"
+
+typedef struct ClientQueries {
+    struct {
+        /* ($address, $pk_base64, $name, $description) -> void */
+        tsqlite_statement* insert;
+        /* ($address, $name, $description) -> void */
+        tsqlite_statement* update;
+        /* ($address) -> 1 or nothing */
+        tsqlite_statement* exists;
+        /* ($address, $pk_base64) -> 1 or nothing */
+        tsqlite_statement* compare_pk;
+        /* () -> [(*)] */
+        tsqlite_statement* get_all;
+    } servers;
+} ClientQueries;

src/cli/ClientCLI/main_screen.c

@@ -0,0 +1,302 @@
+#include "ClientCLI.h"
+#include "tlibc/term.h"
+#include "network/tcp-chat-protocol/v1.h"
+#include "tim.h"
+
+
+static const str greeting_art = STR(
+    "   ^,,^                           ╱|\n"
+    "  ( •·•)   Meum!                (o.o`7\n"
+    "  / ` |                 Meum...  |`˜ \\\n"
+    "\\(_,J J                          L l`,)/\n"
+);
+    
+static const str farewell_art = STR(
+    "   ^,,^                           ╱|\n"
+    "  ( -.-)                        (>,<`7\n"
+    "  / ` |        Goodbye!          |`˜ \\\n"
+    "\\(_,J J                          L l`,)/\n"
+);
+
+
+static void draw_test_label(void* data, TimRect place, bool is_selected);
+static void draw_central_panel(void* data, TimRect place);
+static Result(SavedServer*) joinNewServer(ClientCLI* self);
+static Result(SavedServer*) selectServerFromCache(ClientCLI* self);
+static Result(void) showSavedServer(ClientCLI* self, SavedServer* server);
+static Result(void) registerAtServer(ClientCLI* self);
+static Result(void) loginAtServer(ClientCLI* self);
+
+
+void MainScreenContext_construct(MainScreenContext* ctx, ClientCLI* client){
+    zeroStruct(ctx);
+    ctx->client = client;
+    ///////////////////////////////////////////////////////////////////////////
+    //                             central_panel                             //
+    ///////////////////////////////////////////////////////////////////////////
+    {
+        List(TimPanelItem) items = List_TimPanelItem_alloc(4);
+        
+        TimPanelItem item_test_label = {
+            .w = A, .h = 12, .data = ctx, .draw = draw_test_label
+        };
+        List_TimPanelItem_push(&items, item_test_label);
+        List_TimPanelItem_push(&items, item_test_label);
+        List_TimPanelItem_push(&items, item_test_label);
+        List_TimPanelItem_push(&items, item_test_label);
+
+        ctx->central_panel.items = items.data;
+        ctx->central_panel.len = items.len;
+    }
+    ///////////////////////////////////////////////////////////////////////////
+    //                          central_scroll_view                          //
+    ///////////////////////////////////////////////////////////////////////////
+    {
+        ctx->central_scroll_view.content_h = 50;
+        ctx->central_scroll_view.data = ctx;
+        ctx->central_scroll_view.draw = draw_central_panel;
+    }
+}
+
+void MainScreenContext_destroy(MainScreenContext* ctx){
+    free(ctx->central_panel.items);
+}
+
+void main_screen(MainScreenContext* ctx){
+    if (tim->event.type == TimEvent_Draw) {
+        tim_fill(tim_cell(" ", ctx->client->style.common.fg, ctx->client->style.common.bg), 0, 0, A, A);
+    }
+    
+    if(tim_button_noborder("[Esc/Q] Exit", 1, 0, 14, 1, ctx->client->style.common)
+        || tim_is_key_press('q')
+        || tim_is_key_press(TimKey_Escape))
+    {
+        ctx->client->state = ClientCLIState_Exit;
+    }
+
+    tim_scroll_view(&ctx->central_scroll_view, 0, 1, ~0, ~0, ctx->client->style.common);
+}
+
+static void draw_test_label(void* data, TimRect place, bool is_selected){
+    MainScreenContext* ctx = data;
+    TimStyle style = is_selected ? ctx->client->style.focused : ctx->client->style.common;
+    tim_frame(place.x, place.y, place.w, place.h, style);
+    tim_label("0\n1\n2\n3\n4\n5\n6\n7\n8\n9", 
+        place.x + 1, place.y + 1, place.w - 2, place.h - 2, style);
+}
+
+static void draw_central_panel(void* data, TimRect place){
+    MainScreenContext* ctx = data;
+    tim_panel(&ctx->central_panel, false, place.x, place.y, place.w, place.h);
+}
+
+/*
+static Result(void) ClientCLI_execCommand(ClientCLI* self, str command, bool* stop){
+    Deferral(64);
+
+    if(is_alias("q") || is_alias("quit") || is_alias("exit")){
+        printf(FMT_str"\n", farewell_art.len, farewell_art.data);
+        *stop = true;
+    }
+    else if(is_alias("clear")){
+        term_clear();
+    }
+    else if(is_alias("h") || is_alias("help")){
+        printf(
+           "COMMANDS:\n"
+           "Without connection:\n"
+           "    h, help             Show this message.\n"
+           "    q, quit, exit       Close the program.\n"
+           "    clear               Clear the screen.\n"
+           "Connection:\n"
+           "    j, join             Join a new server and select it.\n"
+           "    s, select           Select a server you joined before.\n"
+           "After connection:\n"
+           "    r, register         Create account on selected server\n"
+           "    l, login            Authorize on selected server\n"
+           "Authorized:\n"
+        );
+    }
+    else if (is_alias("j") || is_alias("join")){
+        // ask address and key, connect to server
+        try_void(joinNewServer(self));
+    }
+    else if(is_alias("s") || is_alias("select")){
+        // show scrollable list of servers, get selected one
+        try_void(selectServerFromCache(self));
+    }
+    else if(is_alias("r") || is_alias("register")){
+        try_void(registerAtServer(self));
+    }
+    else if(is_alias("l") || is_alias("login")){
+        try_void(loginAtServer(self));
+        // TODO: call Client_runIO(): 
+        //      function with infinite loop which sends and receives messages
+        //      with navigation across server channels
+    }
+    else {
+        printf("ERROR: unknown command.\n"
+            "Use 'h' to see list of avaliable commands\n");
+    }
+
+    Return RESULT_VOID;
+}
+*/
+
+static Result(void) joinNewServer(ClientCLI* self){
+    Deferral(8);
+    bool success = false;
+
+    // ask server address
+    const u32 address_alloc_size = HOSTADDR_SIZE_MAX + 1;
+    str address = str_construct((char*)malloc(address_alloc_size), address_alloc_size, true);
+    Defer(if(!success) str_destroy(address));
+    printf("Enter server address (ip:port):\n");
+    try_void(term_readLine(address.data, address.len));
+    address.len = strlen(address.data);
+    str_trim(&address, true);
+
+    // ask server public key
+    const u32 server_pk_alloc_size = PUBLIC_KEY_BASE64_SIZE_MAX + 1;
+    str server_pk = str_construct((char*)malloc(server_pk_alloc_size), server_pk_alloc_size, true);
+    Defer(if(!success) str_destroy(server_pk));
+    printf("Enter server public key (RSA-Public-<SIZE>:<DATA>):\n");
+    try_void(term_readLine(server_pk.data, server_pk.len));
+    server_pk.len = strlen(server_pk.data);
+    str_trim(&server_pk, true);
+    
+    printf("Connecting to server...\n");
+    try_void(Client_connect(self->client, address.data, server_pk.data));
+    printf("Connection established\n");
+    
+    str server_name = str_null;
+    try_void(Client_getServerName(self->client, &server_name));
+    Defer(if(!success) str_destroy(server_name));
+    str server_description = str_null;
+    try_void(Client_getServerDescription(self->client, &server_description));
+    Defer(if(!success) str_destroy(server_description));
+
+    SavedServer server = SavedServer_construct(
+        address,
+        server_pk, 
+        server_name,
+        server_description
+    );
+    try_void(SavedServer_createOrUpdate(self->queries, &server));
+    List_SavedServer_pushMany(&self->saved_servers, &server, 1);
+
+    try_void(showSavedServer(self, &server));
+
+    success = true;
+    Return RESULT_VOID;
+}
+
+static Result(void) selectServerFromCache(ClientCLI* self){
+    Deferral(8);
+    bool success = false;
+
+    u32 servers_count = self->saved_servers.len;
+    if(servers_count == 0){
+        printf("No saved servers found\n");
+        Return RESULT_VOID;
+    }
+
+    for(u32 i = 0; i < servers_count; i++){
+        SavedServer* server = &self->saved_servers.data[i];
+        printf("[%02u] "FMT_str" "FMT_str"\n", 
+            i, str_unwrap(server->address), str_unwrap(server->name));
+    }
+
+    char buf[32];
+    u32 selected_i = -1;
+    while(true) {
+        printf("Type 'q' to cancel\n");
+        printf("Select server number: ");
+        try_void(term_readLine(buf, sizeof(buf)));
+        str input_line = str_from_cstr(buf);
+        str_trim(&input_line, true);
+        if(str_equals(input_line, STR("q"))){
+            Return RESULT_VOID;
+        }
+        if(sscanf(buf, FMT_u32, &selected_i) != 1){
+            printf("ERROR: not a number\n");
+        }
+        else if(selected_i >= servers_count){
+            printf("ERROR: not a server number\n");
+        }
+        else break;
+    }
+    SavedServer* selected_server = &self->saved_servers.data[selected_i];
+
+    printf("Connecting to '"FMT_str"'...\n", str_unwrap(selected_server->address));
+    try_void(Client_connect(self->client, selected_server->address.data, selected_server->pk_base64.data));
+    printf("Connection established\n");
+    
+    // update server name
+    bool server_info_changed = false;
+    str updated_server_name = str_null;
+    try_void(Client_getServerName(self->client, &updated_server_name));
+    Defer(if(!success) str_destroy(updated_server_name));
+    if(!str_equals(updated_server_name, selected_server->name)){
+        server_info_changed = true;
+        selected_server->name = updated_server_name;
+    }
+
+    // update server description
+    str updated_server_description = str_null;
+    try_void(Client_getServerDescription(self->client, &updated_server_description));
+    Defer(if(!success) str_destroy(updated_server_description));
+    if(!str_equals(updated_server_description, selected_server->description)){
+        server_info_changed = true;
+        selected_server->description = updated_server_description;
+    }
+
+    if(server_info_changed){
+        try_void(SavedServer_createOrUpdate(self->queries, selected_server));
+    }
+
+    try_void(showSavedServer(self, selected_server));
+
+    success = true;
+    Return RESULT_VOID;
+}
+
+static Result(void) showSavedServer(ClientCLI* self, SavedServer* server){
+    Deferral(8);
+    (void)self;
+
+    printf("Server Name:  "FMT_str"\n", str_unwrap(server->name));
+    printf("Host Address: "FMT_str"\n", str_unwrap(server->address));
+    printf("Description:\n"FMT_str"\n\n", str_unwrap(server->description));
+    printf("Public Key:\n" FMT_str"\n\n", str_unwrap(server->pk_base64));
+    printf("Type 'register' if you don't have an account on the server.\n");
+    printf("Type 'login' to authorize on the server.\n");
+
+    Return RESULT_VOID;
+}
+
+static Result(void) registerAtServer(ClientCLI* self){
+    Deferral(8);
+
+    i64 user_id = 0;
+    try_void(Client_register(self->client, &user_id));
+    printf("Registered successfully\n");
+    printf("user_id: "FMT_i64"\n", user_id);
+    try_assert(user_id > 0);
+    // TODO: use user_id somewhere
+    
+    Return RESULT_VOID;
+}
+
+static Result(void) loginAtServer(ClientCLI* self){
+    Deferral(8);
+
+    i64 user_id = 0, landing_channel_id = 0;
+    try_void(Client_login(self->client, &user_id, &landing_channel_id));
+    printf("Authorized successfully\n");
+    printf("user_id: "FMT_i64", landing_channel_id: "FMT_i64"\n", user_id, landing_channel_id);
+    try_assert(user_id > 0);
+    // TODO: use user_id, landing_channel_id somewhere
+
+    Return RESULT_VOID;
+}

src/cli/ClientCLI/start_screen.c

@@ -0,0 +1,195 @@
+#include "ClientCLI.h"
+#include "network/tcp-chat-protocol/v1.h"
+#include "tlibc/filesystem.h"
+
+static void draw_central_buttons_panel(void* data, TimRect place, bool is_selected);
+static void draw_start_button(void* data, TimRect place, bool is_selected);
+static void draw_exit_button(void* data, TimRect place, bool is_selected);
+static Result(void) openUserDB(StartScreenContext* ctx);
+
+
+#define handleError(R) _handleError(ctx, R)
+static void _handleError(StartScreenContext* ctx, ResultVar(void) r){
+    free(ctx->err_msg);
+    ctx->err_msg = Error_toStr(r.error).data;
+    Error_free(r.error);
+}
+
+static void clearError(StartScreenContext* ctx){
+    free(ctx->err_msg);
+    ctx->err_msg = NULL;
+}
+
+void StartScreenContext_construct(StartScreenContext* ctx, ClientCLI* client){
+    zeroStruct(ctx);
+    ctx->client = client;
+    ///////////////////////////////////////////////////////////////////////////
+    //                            input_username                             //
+    ///////////////////////////////////////////////////////////////////////////
+    {
+        Array(char) username_buf = Array_char_alloc(USERNAME_SIZE_MAX + 1);
+        TextInputState_construct(&ctx->input_username, "[username]", 
+            username_buf, NULL, false,
+            ctx->client->style.common, ctx->client->style.focused);
+    }    
+    ///////////////////////////////////////////////////////////////////////////
+    //                            input_password                             //
+    ///////////////////////////////////////////////////////////////////////////
+    {
+        Array(char) password_buf = Array_char_alloc(PASSWORD_SIZE_MAX + 1);
+        TextInputState_construct(&ctx->input_password, "[password]", 
+            password_buf, NULL, true,
+            ctx->client->style.common, ctx->client->style.focused);
+    }
+    ///////////////////////////////////////////////////////////////////////////
+    //                             central_panel                             //
+    ///////////////////////////////////////////////////////////////////////////
+    {
+        List(TimPanelItem) items = List_TimPanelItem_alloc(4);
+        
+        TimPanelItem item_username_input;
+        TimPanelItem_fromTextInputState(&item_username_input, &ctx->input_username);
+        List_TimPanelItem_push(&items, item_username_input);
+
+        TimPanelItem item_password_input;
+        TimPanelItem_fromTextInputState(&item_password_input, &ctx->input_password);
+        List_TimPanelItem_push(&items, item_password_input);
+
+        TimPanelItem item_central_buttons_panel = { 
+            .w = A, .h = 3, .data = ctx, .draw = draw_central_buttons_panel
+        };
+        List_TimPanelItem_push(&items, item_central_buttons_panel);
+
+        ctx->central_panel.items = items.data;
+        ctx->central_panel.len = items.len;
+    }
+    ///////////////////////////////////////////////////////////////////////////
+    //                         central_buttons_panel                         //
+    ///////////////////////////////////////////////////////////////////////////
+    {
+        List(TimPanelItem) items = List_TimPanelItem_alloc(4);
+
+        TimPanelItem item_start_button = {
+            .w = A, .h = 3, .data = ctx, .draw = draw_start_button
+        };
+        List_TimPanelItem_push(&items, item_start_button);
+
+        TimPanelItem item_exit_button = {
+            .w = A, .h = 3, .data = ctx, .draw = draw_exit_button
+        };
+        List_TimPanelItem_push(&items, item_exit_button);
+
+        ctx->central_buttons_panel.items = items.data;
+        ctx->central_buttons_panel.len = items.len;
+        ctx->central_buttons_panel.is_horizontal = true;
+    }
+}
+
+void StartScreenContext_destroy(StartScreenContext* ctx){
+    free(ctx->input_username.edit.s);
+    free(ctx->input_password.edit.s);
+    free(ctx->err_msg);
+    free(ctx->central_panel.items);
+    free(ctx->central_buttons_panel.items);
+}
+
+void start_screen(StartScreenContext* ctx)
+{
+    if (tim->event.type == TimEvent_Draw) {
+        tim_fill(tim_cell(" ", ctx->client->style.common.fg, ctx->client->style.common.bg), 0, 0, A, A);
+    }
+    
+    tim_frame(A, A, 40, 11, ctx->client->style.common);
+    tim_panel(&ctx->central_panel, true, A, A, 38, 9);
+    
+    if(ctx->err_msg){
+        i32 below_list = tim->scopes[tim->scope].h/2 + 6;
+        tim_label("ERROR: ", A, below_list, A, A, ctx->client->style.error);
+        tim_label(ctx->err_msg, A, below_list + 1, A, A, ctx->client->style.error);
+    }
+}
+
+static void draw_central_buttons_panel(void* data, TimRect place, bool is_selected){
+    StartScreenContext* ctx = data;
+    tim_panel(&ctx->central_buttons_panel, is_selected, place.x, place.y, place.w, place.h);
+}
+
+static void draw_start_button(void* data, TimRect place, bool is_selected){
+    StartScreenContext* ctx = data;
+    TimStyle style = is_selected ? ctx->client->style.focused : ctx->client->style.common;
+    if(tim_button("[Enter] Start", place.x, place.y, place.w, A, style) 
+        || tim_is_key_press(TimKey_Enter))
+    {
+        clearError(ctx);
+
+        // check username
+        str username = str_from_cstr(ctx->input_username.edit.s);
+        str_trim(&username, true);
+        str name_error_str = validateUsername_str(username);
+        if(name_error_str.data){
+            ctx->err_msg = name_error_str.data;
+            return;
+        }
+
+        // check password
+        str password = str_from_cstr(ctx->input_password.edit.s);
+        str_trim(&password, true);
+        if(password.len < PASSWORD_SIZE_MIN || password.len > PASSWORD_SIZE_MAX){
+            ctx->err_msg = sprintf_malloc(
+                "password length (in bytes) must be >= %i and <= %i", 
+                PASSWORD_SIZE_MIN, PASSWORD_SIZE_MAX
+            );
+            return;
+        }
+        
+        // create client
+        try_handle(ctx->client->client, p, Client_create(username, password), handleError);
+        // init user DB
+        try_handle_void(openUserDB(ctx), handleError);
+        // erase password from memory
+        memset(ctx->input_password.edit.s, 0, ctx->input_password.edit.capacity);
+        // switch to next screen
+        ctx->client->state = ClientCLIState_MainScreen;
+        return;
+    }
+}
+
+static void draw_exit_button(void* data, TimRect place, bool is_selected){
+    StartScreenContext* ctx = data;
+    TimStyle style = is_selected ? ctx->client->style.focused : ctx->client->style.common;
+    if(tim_button("[Esc/Q] Exit", place.x, place.y, place.w, A, style) 
+        || tim_is_key_press('q') 
+        || tim_is_key_press(TimKey_Escape)
+        || ctx->input_username.result_key == TimKey_Escape 
+        || ctx->input_password.result_key == TimKey_Escape)
+    {
+        ctx->client->state = ClientCLIState_Exit;
+        return;
+    }
+}
+
+static Result(void) openUserDB(StartScreenContext* ctx){
+    Deferral(8);
+
+    str username = Client_getUserName(ctx->client->client);
+    // TODO: encrypt user database
+    // Array(u8) user_data_key = Client_getUserDataKey(ctx->client->client);
+    
+    // build database file path
+    try(char* user_dir, p, path_getUserDir());
+    Defer(free(user_dir));
+    char* db_path = strcat_malloc(
+        user_dir,
+        path_seps".local"path_seps"tcp-chat-client"path_seps"user-db"path_seps,
+        username.data, ".sqlite"
+    );
+    Defer(free(db_path));
+    
+    try(ctx->client->db, p, ClientDatabase_open(db_path));
+    try(ctx->client->queries, p, ClientQueries_compile(ctx->client->db));
+
+    // load whole servers table to list
+    try_void(SavedServer_getAll(ctx->client->queries, &ctx->client->saved_servers));
+
+    Return RESULT_VOID;
+}

src/cli/ClientCLI/widgets.c

@@ -0,0 +1,32 @@
+#include "ClientCLI.h"
+
+void TextInputState_construct(TextInputState* ctx, cstr label, 
+    Array(char) buf, NULLABLE(cstr) initial_value, bool masked, 
+    TimStyle common, TimStyle focused)
+{
+    TimEditState_construct(&ctx->edit, buf.data, buf.len, initial_value);
+    ctx->edit.masked = masked;
+    ctx->label = label;
+    ctx->style.common = common;
+    ctx->style.focused = focused;
+}
+
+void text_input(TextInputState* ctx, i32 x, i32 y, i32 w, TimStyle style){
+    ctx->result_key = tim_edit(&ctx->edit, x, y, w, style);
+    tim_label(ctx->label, x + 3, y, A, 1, style);
+}
+
+void TimPanelItem_fromTextInputState(TimPanelItem* item, TextInputState* input){
+    zeroStruct(item);
+    item->w = A;
+    item->h = 3;
+    item->data = input;
+    item->focus_target = &input->edit;
+    item->draw = draw_item_text_input;
+}
+
+void draw_item_text_input(void* data, TimRect place, bool is_selected){
+    TextInputState* ctx = data;
+    TimStyle style = is_selected ? ctx->style.focused : ctx->style.common;
+    text_input(ctx, place.x, place.y, place.w, style);
+}

src/cli/main.c

@@ -1,6 +1,6 @@
+#include "tcp-chat.h"
 #include "tlibc/tlibc.h"
 #include "tlibtoml.h"
-#include "tcp-chat/tcp-chat.h"
 #include "cryptography/RSA.h"
 #include "cli/modes/modes.h"
 

src/cli/modes/ClientMode.c

@@ -9,7 +9,7 @@ Result(void) run_ClientMode(cstr config_path) {
     ClientCLI_construct(&client);
     Defer(ClientCLI_destroy(&client));
 	// start infinite loop on main thread
-    try_void(ClientCLI_run(&client));
+    ClientCLI_run(&client);
 
     Return RESULT_VOID;
 }

src/cli/modes/ServerMode.c

@@ -1,8 +1,8 @@
+#include <pthread.h>
+#include "tcp-chat.h"
 #include "modes.h"
-#include "tcp-chat/server.h"
 #include "tlibc/time.h"
 #include "tlibc/term.h"
-#include <pthread.h>
 
 typedef struct ServerLogger {
     pthread_mutex_t mutex;

src/client/ServerConnection.c

@@ -8,8 +8,7 @@ void ServerConnection_close(ServerConnection* self){
     EncryptedSocketTCP_destroy(&self->sock);
     Array_u8_destroy(&self->token);
     Array_u8_destroy(&self->session_key);
-    str_destroy(self->server_name);
-    str_destroy(self->server_description);
+    MessageBlock_destroy(&self->received_message_block);
     free(self);
 }
 
@@ -75,16 +74,13 @@ Result(ServerConnection*) ServerConnection_open(Client* client, cstr server_addr
         PacketType_ServerHandshake));
     conn->session_id = server_handshake.session_id;
 
-    // get server name
-    try_void(ServerConnection_requestServerName(conn));
-    // get server description
-    try_void(ServerConnection_requestServerDescription(conn));
+    MessageBlock_alloc(&conn->received_message_block);
 
     success = true;
     Return RESULT_VALUE(p, conn);
 }
 
-Result(void) ServerConnection_requestServerName(ServerConnection* conn){
+Result(void) ServerConnection_requestServerName(ServerConnection* conn, str* out_str){
     if(conn == NULL){
         return RESULT_ERROR_LITERAL("Client is not connected to a server");
     }
@@ -98,12 +94,12 @@ Result(void) ServerConnection_requestServerName(ServerConnection* conn){
     try_void(sendRequest(&conn->sock, &req_header, &public_info_req));
     try_void(recvResponse(&conn->sock, &res_header, &public_info_res,
         PacketType_ServerPublicInfoResponse));
-    try_void(recvStr(&conn->sock, public_info_res.data_size, &conn->server_name));
+    try_void(recvStr(&conn->sock, public_info_res.data_size, out_str));
 
     Return RESULT_VOID;
 }
 
-Result(void) ServerConnection_requestServerDescription(ServerConnection* conn){
+Result(void) ServerConnection_requestServerDescription(ServerConnection* conn, str* out_str){
     if(conn == NULL){
         return RESULT_ERROR_LITERAL("Client is not connected to a server");
     }
@@ -117,7 +113,7 @@ Result(void) ServerConnection_requestServerDescription(ServerConnection* conn){
     try_void(sendRequest(&conn->sock, &req_header, &public_info_req));
     try_void(recvResponse(&conn->sock, &res_header, &public_info_res,
         PacketType_ServerPublicInfoResponse));
-    try_void(recvStr(&conn->sock, public_info_res.data_size, &conn->server_description));
+    try_void(recvStr(&conn->sock, public_info_res.data_size, out_str));
 
     Return RESULT_VOID;
 }

src/client/client.c

@@ -52,27 +52,27 @@ Array(u8) Client_getUserDataKey(Client* client){
     return client->user_data_key;
 }
 
-Result(void) Client_getServerName(Client* self, str* out_name){
+Result(void) Client_getServerName(Client* self, str* out_str){
     Deferral(1);
     try_assert(self != NULL);
     try_assert(self->conn != NULL && "didn't connect to a server yet");
 
-    *out_name = self->conn->server_name;
+    try_void(ServerConnection_requestServerName(self->conn, out_str));
 
     Return RESULT_VOID;
 }
 
-Result(void) Client_getServerDescription(Client* self, str* out_desc){
+Result(void) Client_getServerDescription(Client* self, str* out_str){
     Deferral(1);
     try_assert(self != NULL);
     try_assert(self->conn != NULL && "didn't connect to a server yet");
 
-    *out_desc = self->conn->server_description;
+    try_void(ServerConnection_requestServerDescription(self->conn, out_str));
     
     Return RESULT_VOID;
 }
 
-Result(void) Client_register(Client* self, u64* out_user_id){
+Result(void) Client_register(Client* self, i64* out_user_id){
     Deferral(1);
     try_assert(self != NULL);
     try_assert(self->conn != NULL && "didn't connect to a server yet");
@@ -80,7 +80,6 @@ Result(void) Client_register(Client* self, u64* out_user_id){
     PacketHeader req_head, res_head;
     RegisterRequest req;
     RegisterResponse res;
-    // TODO: hash token with server public key
     try_void(RegisterRequest_tryConstruct(&req, &req_head, self->username, self->conn->token));
     try_void(sendRequest(&self->conn->sock, &req_head, &req));
     try_void(recvResponse(&self->conn->sock, &res_head, &res, PacketType_RegisterResponse));
@@ -90,7 +89,7 @@ Result(void) Client_register(Client* self, u64* out_user_id){
     Return RESULT_VOID;
 }
 
-Result(void) Client_login(Client* self, u64* out_user_id, u64* out_landing_channel_id){
+Result(void) Client_login(Client* self, i64* out_user_id, i64* out_landing_channel_id){
     Deferral(1);
     try_assert(self != NULL);
     try_assert(self->conn != NULL && "didn't connect to a server yet");
@@ -98,7 +97,6 @@ Result(void) Client_login(Client* self, u64* out_user_id, u64* out_landing_chann
     PacketHeader req_head, res_head;
     LoginRequest req;
     LoginResponse res;
-    // TODO: hash token with server public key
     try_void(LoginRequest_tryConstruct(&req, &req_head, self->username, self->conn->token));
     try_void(sendRequest(&self->conn->sock, &req_head, &req));
     try_void(recvResponse(&self->conn->sock, &res_head, &res, PacketType_LoginResponse));
@@ -108,3 +106,71 @@ Result(void) Client_login(Client* self, u64* out_user_id, u64* out_landing_chann
 
     Return RESULT_VOID;
 }
+
+Result(i64) Client_sendMessage(Client* self, i64 channel_id, Array(u8) content, DateTime* out_timestamp){
+    Deferral(1);
+    try_assert(self != NULL);
+    try_assert(self->conn != NULL && "didn't connect to a server yet");
+    try_assert(content.len >= MESSAGE_SIZE_MIN && content.len <= MESSAGE_SIZE_MAX);
+
+    PacketHeader req_head, res_head;
+    SendMessageRequest req;
+    SendMessageResponse res;
+    SendMessageRequest_construct(&req, &req_head, channel_id, content.len);
+    try_void(sendRequest(&self->conn->sock, &req_head, &req));
+    try_void(recvResponse(&self->conn->sock, &res_head, &res, PacketType_SendMessageResponse));
+    *out_timestamp = res.timestamp;
+
+    Return RESULT_VALUE(i, res.message_id);
+}
+
+Result(u32) Client_receiveMessageBlock(Client* self, i64 channel_id, i64 first_message_id, u32 messages_count){
+    Deferral(1);
+    try_assert(self != NULL);
+    try_assert(self->conn != NULL && "didn't connect to a server yet");
+
+    PacketHeader req_head, res_head;
+    GetMessageBlockRequest req;
+    GetMessageBlockResponse res;
+    GetMessageBlockRequest_construct(&req, &req_head, channel_id, first_message_id, messages_count);
+    try_void(sendRequest(&self->conn->sock, &req_head, &req));
+    try_void(recvResponse(&self->conn->sock, &res_head, &res, PacketType_GetMessageBlockResponse));
+    self->conn->received_message_block.messages_count = res.messages_count;
+    self->conn->received_message_block.datum.len = res.data_size;
+    try_void(
+        EncryptedSocketTCP_recv(
+            &self->conn->sock, 
+            self->conn->received_message_block.datum, 
+            SocketRecvFlag_WholeBuffer
+        )
+    );
+
+    Return RESULT_VALUE(u, res.messages_count);
+}
+
+Result(u32) Client_popMessage(Client* self, Array(u8) dst_content, 
+    i64* message_id, i64* sender_id, DateTime* timestamp_utc)
+{
+    Deferral(1);
+    try_assert(self != NULL);
+    try_assert(self->conn != NULL && "didn't connect to a server yet");
+    try_assert(dst_content.len >= MESSAGE_SIZE_MAX);
+
+    MessageMeta msg_meta = {0};
+    try(bool read_success, u, 
+        MessageBlock_readMessage(
+            &self->conn->received_message_block, 
+            &msg_meta,
+            dst_content
+        )
+    );
+    if(!read_success){
+        Return RESULT_VALUE(u, 0);
+    }
+
+    *message_id = msg_meta.id;
+    *sender_id = msg_meta.sender_id;
+    *timestamp_utc = msg_meta.timestamp;
+    
+    Return RESULT_VALUE(u, msg_meta.data_size);
+}

src/client/client_internal.h

@@ -1,8 +1,9 @@
 #pragma once
-#include "tcp-chat/client.h"
+#include "tcp-chat.h"
 #include "cryptography/AES.h"
 #include "cryptography/RSA.h"
 #include "network/encrypted_sockets.h"
+#include "network/tcp-chat-protocol/v1.h"
 
 typedef struct ServerConnection ServerConnection;
 
@@ -12,7 +13,6 @@ typedef struct Client {
     ServerConnection* conn;
 } Client;
 
-
 typedef struct ServerConnection {
     Client* client;
     EndpointIPv4 server_end;
@@ -21,10 +21,9 @@ typedef struct ServerConnection {
     Array(u8) token;
     Array(u8) session_key;
     EncryptedSocketTCP sock;
-    u64 session_id;
-    str server_name;
-    str server_description;
-    u64 user_id;
+    i64 session_id;
+    i64 user_id;
+    MessageBlock received_message_block;
 } ServerConnection;
 
 /// @param server_addr_cstr 
@@ -34,8 +33,8 @@ Result(ServerConnection*) ServerConnection_open(Client* client,
 
     void ServerConnection_close(ServerConnection* conn);
 
-/// updates conn->server_name
-Result(void) ServerConnection_requestServerName(ServerConnection* conn);
+/// @param out_str heap-allocated string
+Result(void) ServerConnection_requestServerName(ServerConnection* conn, str* out_str);
 
-/// updates conn->server_description
-Result(void) ServerConnection_requestServerDescription(ServerConnection* conn);
+/// @param out_str heap-allocated string
+Result(void) ServerConnection_requestServerDescription(ServerConnection* conn, str* out_str);

src/client/requests/ErrorMessage.c

@@ -1,6 +1,6 @@
 #include "requests.h"
 
-Result(void) recvStr(EncryptedSocketTCP* sock, u32 size, str* out_s){
+Result(void) recvStr(EncryptedSocketTCP* sock, u32 size, str* out_str){
     Deferral(4);
     
     str s = str_construct(malloc(size + 1), size, true);
@@ -17,7 +17,7 @@ Result(void) recvStr(EncryptedSocketTCP* sock, u32 size, str* out_s){
     );
 
     s.data[s.len] = 0;
-    *out_s = s;
+    *out_str = s;
     success = true;
     Return RESULT_VOID;
 }

src/client/requests/requests.h

@@ -3,10 +3,12 @@
 #include "client/client_internal.h"
 
 
+/// @param out_err_msg heap-allocated string
 Result(void) recvErrorMessage(EncryptedSocketTCP* sock, PacketHeader* res_header,
     str* out_err_msg);
 
-Result(void) recvStr(EncryptedSocketTCP* sock, u32 size, str* out_s);
+/// @param out_str heap-allocated string
+Result(void) recvStr(EncryptedSocketTCP* sock, u32 size, str* out_str);
 
 Result(void) _recvResponse(EncryptedSocketTCP* sock,
     PacketHeader* res_header, Array(u8) res, PacketType res_type);

src/cryptography/RSA.c

@@ -1,7 +1,5 @@
 #include "RSA.h"
 #include <assert.h>
-#include "bearssl_x509.h"
-#include "bearssl_pem.h"
 #include "tlibc/base64.h"
 
 // https://crypto.stackexchange.com/questions/3110/impacts-of-not-using-rsa-exponent-of-65537

src/cryptography/cryptography.h

@@ -1,10 +1,9 @@
 #pragma once
-#include "tlibc/errors.h"
+#include "tcp-chat.h"
 #include "tlibc/collections/Array.h"
 #include "tlibc/collections/Array_impl/Array_u8.h"
 #include "bearssl_rand.h"
 #include "bearssl_hash.h"
-#include "tcp-chat/common_constants.h"
 
 //////////////////////////////////////////////////////////////////////////////
 //                                                                          //

src/network/internal.h

@@ -1,5 +1,5 @@
 #pragma once
-#include "tcp-chat/tcp-chat.h"
+#include "tcp-chat.h"
 #include "endpoint.h"
 
 #if !defined(KN_USE_WINSOCK)

src/network/socket.c

@@ -132,12 +132,12 @@ Result(i32) socket_recvfrom(Socket s, Array(u8) buffer, SocketRecvFlag flags, NU
 }
 
 Result(void) socket_TCP_enableAliveChecks(Socket s,
-    sec_t first_check_time, u32 checks_count, sec_t checks_interval)
+    sec_t first_check_time, u32 check_count, sec_t checks_interval)
 {
 #if KN_USE_WINSOCK
     BOOL opt_SO_KEEPALIVE = 1; // enable keepalives
     DWORD opt_TCP_KEEPIDLE = first_check_time;
-    DWORD opt_TCP_KEEPCNT = checks_count;
+    DWORD opt_TCP_KEEPCNT = check_count;
     DWORD opt_TCP_KEEPINTVL = checks_interval;
     try_setsockopt(s, SOL_SOCKET, SO_KEEPALIVE);
     try_setsockopt(s, IPPROTO_TCP, TCP_KEEPIDLE);
@@ -145,12 +145,12 @@ Result(void) socket_TCP_enableAliveChecks(Socket s,
     try_setsockopt(s, IPPROTO_TCP, TCP_KEEPINTVL);
 
     // timeout for connect() 
-    DWORD opt_TCP_MAXRT = checks_count * checks_interval; 
+    DWORD opt_TCP_MAXRT = check_count * checks_interval; 
     try_setsockopt(s, IPPROTO_TCP, TCP_MAXRT);
 #else
     int opt_SO_KEEPALIVE = 1; // enable keepalives
     int opt_TCP_KEEPIDLE = first_check_time;
-    int opt_TCP_KEEPCNT = checks_count;
+    int opt_TCP_KEEPCNT = check_count;
     int opt_TCP_KEEPINTVL = checks_interval;
     try_setsockopt(s, SOL_SOCKET, SO_KEEPALIVE);
     try_setsockopt(s, IPPROTO_TCP, TCP_KEEPIDLE);
@@ -158,7 +158,7 @@ Result(void) socket_TCP_enableAliveChecks(Socket s,
     try_setsockopt(s, IPPROTO_TCP, TCP_KEEPINTVL);
 
     // read more in the article
-    int opt_TCP_USER_TIMEOUT = checks_count * checks_interval * 1000;
+    int opt_TCP_USER_TIMEOUT = check_count * checks_interval * 1000;
     try_setsockopt(s, IPPROTO_TCP, TCP_USER_TIMEOUT);
 #endif
     return RESULT_VOID;

src/network/socket.h

@@ -38,7 +38,7 @@ Result(i32)     socket_recvfrom(Socket s, Array(u8) buffer, SocketRecvFlag flags
 /// Read more: https://blog.cloudflare.com/when-tcp-sockets-refuse-to-die/
 /// RU translaton: https://habr.com/ru/articles/700470/
 Result(void) socket_TCP_enableAliveChecks(Socket s,
-    sec_t first_check_time, u32 checks_count, sec_t checks_interval);
+    sec_t first_check_time, u32 check_count, sec_t checks_interval);
 #define socket_TCP_enableAliveChecks_default(socket) \
     socket_TCP_enableAliveChecks(socket, 1, 4, 5)
 

src/network/tcp-chat-protocol/constant.h

@@ -1,7 +1,6 @@
 #pragma once
-#include "tlibc/errors.h"
+#include "tcp-chat.h"
 #include "tlibc/magic.h"
-#include "tcp-chat/common_constants.h"
 
 #define AES_SESSION_KEY_SIZE 32
 

src/network/tcp-chat-protocol/v1.c

@@ -19,7 +19,7 @@ str validateUsername_str(str username){
     if(username.len < USERNAME_SIZE_MIN || username.len > USERNAME_SIZE_MAX){
         return str_from_cstr(
             sprintf_malloc(
-                "username length (in bytes) must be >= %i and <= %i\n", 
+                "username length (in bytes) must be >= %i and <= %i", 
                 USERNAME_SIZE_MIN, USERNAME_SIZE_MAX
             )
         );
@@ -63,7 +63,7 @@ Result(void) ClientHandshake_tryConstruct(ClientHandshake* ptr, PacketHeader* he
 }
 
 void ServerHandshake_construct(ServerHandshake* ptr, PacketHeader* header,
-    u64 session_id)
+    i64 session_id)
 {
     _PacketHeader_construct(ServerHandshake);
     zeroStruct(ptr);
@@ -106,7 +106,7 @@ Result(void) LoginRequest_tryConstruct(LoginRequest *ptr, PacketHeader* header,
 }
 
 void LoginResponse_construct(LoginResponse* ptr, PacketHeader* header,
-    u64 user_id, u64 landing_channel_id)
+    i64 user_id, i64 landing_channel_id)
 {
     _PacketHeader_construct(LoginResponse);
     zeroStruct(ptr);
@@ -135,15 +135,78 @@ Result(void) RegisterRequest_tryConstruct(RegisterRequest *ptr, PacketHeader* he
 }
 
 void RegisterResponse_construct(RegisterResponse *ptr, PacketHeader* header,
-    u64 user_id)
+    i64 user_id)
 {
     _PacketHeader_construct(RegisterResponse);
     zeroStruct(ptr);
     ptr->user_id = user_id;
 }
 
+Result(bool) MessageBlock_writeMessage(MessageBlock* block,
+    const MessageMeta* msg_meta, const Array(u8) msg_content)
+{
+    Deferral(1);
+
+    // check msg_meta
+    try_assert(msg_meta->magic.n == MESSAGE_MAGIC.n);
+    try_assert(msg_meta->data_size >= MESSAGE_SIZE_MIN && msg_meta->data_size <= MESSAGE_SIZE_MAX);
+    try_assert(msg_meta->data_size <= msg_content.len);
+    try_assert(msg_meta->id > 0);
+    try_assert(msg_meta->sender_id > 0);
+    try_assert(msg_meta->timestamp.d.year > 2024);
+    // check block->datum.len
+    if(block->datum.len < block->offset + sizeof(MessageMeta) + msg_meta->data_size){
+        Return RESULT_VALUE(u, false);
+    }
+    
+    // write msg_meta
+    memcpy(block->datum.data + block->offset, msg_meta, sizeof(MessageMeta));
+    block->offset += sizeof(MessageMeta);
+
+    // write msg_content
+    memcpy(block->datum.data + block->offset, msg_content.data, msg_meta->data_size);
+    block->offset += msg_meta->data_size;
+    
+    block->messages_count++;
+    Return RESULT_VALUE(u, true);
+}
+
+Result(bool) MessageBlock_readMessage(MessageBlock* block,
+    MessageMeta* msg_meta, Array(u8) msg_content)
+{
+    Deferral(1);
+
+    // check block
+    if(block->messages_count == 0){
+        Return RESULT_VALUE(u, false);
+    }
+    try_assert(block->datum.len >= block->offset + sizeof(MessageMeta) + MESSAGE_SIZE_MIN);
+    // check msg_content.len
+    try_assert(msg_content.len >= MESSAGE_SIZE_MAX);
+    
+    // read msg_meta
+    memcpy(msg_meta, block->datum.data + block->offset, sizeof(MessageMeta));
+    block->offset += sizeof(MessageMeta);
+
+    // check msg_meta
+    try_assert(msg_meta->magic.n == MESSAGE_MAGIC.n);
+    try_assert(msg_meta->data_size >= MESSAGE_SIZE_MIN && msg_meta->data_size <= MESSAGE_SIZE_MAX);
+    try_assert(msg_meta->data_size <= msg_content.len);
+    try_assert(msg_meta->id > 0);
+    try_assert(msg_meta->sender_id > 0);
+    try_assert(msg_meta->timestamp.d.year > 2024);
+    try_assert(block->datum.len >= block->offset + msg_meta->data_size);
+
+    // read msg_content
+    memcpy(msg_content.data, block->datum.data + block->offset, msg_meta->data_size);
+    block->offset += msg_meta->data_size;
+
+    block->messages_count--;
+    Return RESULT_VALUE(u, true);
+}
+
 void SendMessageRequest_construct(SendMessageRequest *ptr, PacketHeader *header,
-    u64 channel_id, u16 data_size)
+    i64 channel_id, u16 data_size)
 {
     _PacketHeader_construct(SendMessageRequest);
     zeroStruct(ptr);
@@ -152,16 +215,16 @@ void SendMessageRequest_construct(SendMessageRequest *ptr, PacketHeader *header,
 }
 
 void SendMessageResponse_construct(SendMessageResponse *ptr, PacketHeader *header,
-    u64 message_id, DateTime receiving_time_utc)
+    i64 message_id, DateTime timestamp)
 {
     _PacketHeader_construct(SendMessageResponse);
     zeroStruct(ptr);
     ptr->message_id = message_id;
-    ptr->receiving_time_utc = receiving_time_utc;
+    ptr->timestamp = timestamp;
 }
 
 void GetMessageBlockRequest_construct(GetMessageBlockRequest *ptr, PacketHeader *header,
-    u64 channel_id, u64 first_message_id, u32 messages_count)
+    i64 channel_id, i64 first_message_id, u32 messages_count)
 {
     _PacketHeader_construct(GetMessageBlockRequest);
     zeroStruct(ptr);
@@ -171,11 +234,10 @@ void GetMessageBlockRequest_construct(GetMessageBlockRequest *ptr, PacketHeader
 }
 
 void GetMessageBlockResponse_construct(GetMessageBlockResponse *ptr, PacketHeader *header,
-    u64 first_message_id, u32 messages_count, u32 data_size)
+    u32 messages_count, u32 data_size)
 {
     _PacketHeader_construct(GetMessageBlockResponse);
     zeroStruct(ptr);
-    ptr->first_message_id = first_message_id;
     ptr->messages_count = messages_count;
     ptr->data_size = data_size;
 }

src/network/tcp-chat-protocol/v1.h

@@ -1,6 +1,5 @@
 #pragma once
-#include "tlibc/errors.h"
-#include "tlibc/string/str.h"
+#include "tcp-chat.h"
 #include "tlibc/time.h"
 #include "network/tcp-chat-protocol/constant.h"
 
@@ -60,11 +59,11 @@ Result(void) ClientHandshake_tryConstruct(ClientHandshake* ptr, PacketHeader* he
 
 
 typedef struct ServerHandshake {
-    u64 session_id;
+    i64 session_id;
 } ALIGN_PACKET_STRUCT ServerHandshake;
 
 void ServerHandshake_construct(ServerHandshake* ptr, PacketHeader* header,
-    u64 session_id);
+    i64 session_id);
 
 
 typedef enum ServerPublicInfo {
@@ -99,12 +98,12 @@ Result(void) LoginRequest_tryConstruct(LoginRequest* ptr, PacketHeader* header,
 
 
 typedef struct LoginResponse {
-    u64 user_id;
-    u64 landing_channel_id;
+    i64 user_id;
+    i64 landing_channel_id;
 } ALIGN_PACKET_STRUCT LoginResponse;
 
 void LoginResponse_construct(LoginResponse* ptr, PacketHeader* header,
-    u64 user_id, u64 landing_channel_id);
+    i64 user_id, i64 landing_channel_id);
 
 
 typedef struct RegisterRequest {
@@ -117,49 +116,114 @@ Result(void) RegisterRequest_tryConstruct(RegisterRequest* ptr, PacketHeader* he
 
 
 typedef struct RegisterResponse {
-    u64 user_id;
+    i64 user_id;
 } ALIGN_PACKET_STRUCT RegisterResponse;
 
 void RegisterResponse_construct(RegisterResponse* ptr, PacketHeader* header,
-    u64 user_id);
+    i64 user_id);
+
+
+typedef struct MessageMeta {
+    Magic32 magic;
+    u16 data_size;
+    i64 id;
+    i64 sender_id;
+    DateTime timestamp; /* UTC */
+} ATTRIBUTE_ALIGNED(8) MessageMeta;
+
+#define MessageMeta_construct(DATA_SIZE, MESSAGE_ID, SENDER_ID, TIMESTAMP) ((MessageMeta){ \
+    .magic = MESSAGE_MAGIC, \
+    .data_size = DATA_SIZE, \
+    .id = MESSAGE_ID, \
+    .sender_id = SENDER_ID, \
+    .timestamp = TIMESTAMP \
+})
+
+#define MESSAGE_MAGIC ((Magic32){ .bytes = { 'M', 's', 'g', '1' } })
+
+typedef struct MessageBlock {
+    Array(u8) datum; // sequence(MessageMeta, byte[MessageMeta.data_size])
+    u32 messages_count;
+    u32 offset;
+} MessageBlock;
+
+static inline void MessageBlock_construct(MessageBlock* self, Array(u8) datum, u32 messages_count){
+    self->datum = datum;
+    self->messages_count = messages_count;
+    self->offset = 0;
+}
+
+static inline void MessageBlock_alloc(MessageBlock* self){
+    self->datum = Array_u8_alloc(MESSAGE_BLOCK_COUNT_MAX * (sizeof(MessageMeta) + MESSAGE_SIZE_MAX));
+    Array_u8_memset(&self->datum, 0);
+    self->messages_count = 0;
+    self->offset = 0;
+}
+
+static inline void MessageBlock_reset(MessageBlock* self){
+    Array_u8_memset(&self->datum, 0);
+    self->messages_count = 0;
+    self->offset = 0;
+}
+
+static inline void MessageBlock_destroy(MessageBlock* self){
+    if(!self)
+        return;
+    Array_u8_destroy(&self->datum);
+}
+
+/// @brief write msg_meta and msg_meta->data_size bytes from msg_content to block and increase block.messages_count
+/// @param block use MessageBlock_alloc() to create empty block
+/// @param msg_meta use MessageMeta_construct() to create message metadata
+/// @param msg_content array of size >= msg_meta.data_size
+/// @return false if msg_meta and msg_content don't fit in block.datum
+Result(bool) MessageBlock_writeMessage(MessageBlock* block,
+    const MessageMeta* msg_meta, const Array(u8) msg_content);
+
+/// @brief read msg_meta and msg_content from block and decrease block.messages_count
+/// @param block a block with correct .datum and .messages_count
+/// @param msg_meta out meta copied from block_data
+/// @param msg_content out content copied from block_data. Array of size >= MESSAGE_SIZE_MAX
+/// @return false if there are no messages to read (block.messages_count == 0)
+Result(bool) MessageBlock_readMessage(MessageBlock* block,
+    MessageMeta* msg_meta, Array(u8) msg_content);
 
 
 typedef struct SendMessageRequest {
-    u64 channel_id;
+    i64 channel_id;
     u16 data_size;
     /* stream of size data_size */
 } ALIGN_PACKET_STRUCT SendMessageRequest;
 
 void SendMessageRequest_construct(SendMessageRequest* ptr, PacketHeader* header,
-    u64 channel_id, u16 data_size);
+    i64 channel_id, u16 data_size);
 
 
 typedef struct SendMessageResponse {
-    u64 message_id;
-    DateTime receiving_time_utc;
+    i64 message_id;
+    DateTime timestamp; /* UTC */
 } ALIGN_PACKET_STRUCT SendMessageResponse;
 
 void SendMessageResponse_construct(SendMessageResponse* ptr, PacketHeader* header,
-    u64 message_id, DateTime receiving_time_utc);
+    i64 message_id, DateTime timestamp);
 
 
 typedef struct GetMessageBlockRequest {
-    u64 channel_id;
-    u64 first_message_id;
+    i64 channel_id;
+    i64 first_message_id;
     u32 messages_count;
 } ALIGN_PACKET_STRUCT GetMessageBlockRequest;
 
 void GetMessageBlockRequest_construct(GetMessageBlockRequest* ptr, PacketHeader* header,
-    u64 channel_id, u64 first_message_id, u32 messages_count);
+    i64 channel_id, i64 first_message_id, u32 messages_count);
 
 
 typedef struct GetMessageBlockResponse {
-    u64 first_message_id;
     u32 messages_count;
     u32 data_size;
-    /* stream of size data_size : ((sequence MessageMeta), (sequence binary-data)) */
+    /* stream of size data_size : sequence (MessageMeta, byte[MessageMeta.data_size]) */
 } ALIGN_PACKET_STRUCT GetMessageBlockResponse;
 
 void GetMessageBlockResponse_construct(GetMessageBlockResponse* ptr, PacketHeader* header,
-    u64 first_message_id, u32 messages_count, u32 data_size);
+    u32 messages_count, u32 data_size);
 

src/server/Channel.c

@@ -1,186 +0,0 @@
-#include "server_internal.h"
-#include "tlibc/string/StringBuilder.h"
-#include "tlibc/filesystem.h"
-
-void Channel_free(Channel* self){
-    if(!self)
-        return;
-    str_destroy(self->name);
-    str_destroy(self->description);
-    List_MessageBlockMeta_destroy(&self->messages.blocks_meta_list);
-    LList_MessageBlock_destroy(&self->messages.blocks_queue);
-    free(self);
-}
-
-Result(Channel*) Channel_create(u64 chan_id, str name, str description,
-    IncrementalDB* db, bool lock_db)
-{
-    Deferral(8);
-    
-    Channel* self = (Channel*)malloc(sizeof(Channel));
-    zeroStruct(self);
-    bool success = false;
-    Defer(if(!success) Channel_free(self));
-
-    self->id = chan_id;
-    try_assert(name.len >= CHANNEL_NAME_SIZE_MIN && name.len <= CHANNEL_NAME_SIZE_MAX);
-    self->name = str_copy(name);
-    try_assert(description.len <= CHANNEL_DESC_SIZE_MAX);
-    self->description = str_copy(description);
-
-    if(lock_db){
-        idb_lockDB(db);
-        Defer(idb_unlockDB(db));
-    }
-    
-    StringBuilder sb = StringBuilder_alloc(CHANNEL_NAME_SIZE_MAX + 32 + 1);
-    Defer(StringBuilder_destroy(&sb));
-    StringBuilder_append_str(&sb, STR("channels"));
-    StringBuilder_append_char(&sb, path_sep);
-    StringBuilder_append_str(&sb, name);
-
-    str subdir = str_copy(StringBuilder_getStr(&sb));
-    Defer(str_destroy(subdir));
-    str message_blocks_str = STR("message_blocks");
-    str message_blocks_meta_str = STR("message_blocks_meta");
-    
-    StringBuilder_removeFromEnd(&sb, -1);
-    StringBuilder_append_str(&sb, name);
-    StringBuilder_append_char(&sb, '_');
-    StringBuilder_append_str(&sb, message_blocks_str);
-    try(self->messages.blocks_table, p, 
-        idb_getOrCreateTable(db, subdir, StringBuilder_getStr(&sb), sizeof(MessageBlock), false)
-    );
-    idb_lockTable(self->messages.blocks_table);
-    Defer(idb_unlockTable(self->messages.blocks_table));
-
-    
-    StringBuilder_removeFromEnd(&sb, message_blocks_str.len);
-    StringBuilder_append_str(&sb, message_blocks_meta_str);
-    try(self->messages.blocks_meta_table, p, 
-        idb_getOrCreateTable(db, subdir, StringBuilder_getStr(&sb), sizeof(MessageBlockMeta), false)
-    );
-    idb_lockTable(self->messages.blocks_meta_table);
-    Defer(idb_unlockTable(self->messages.blocks_meta_table));
-
-    // load whole message_blocks_meta table to list
-    try_void(
-        idb_createListFromTable(self->messages.blocks_meta_table, (void*)&self->messages.blocks_meta_list, false)
-    );
-    
-    // load N last blocks to the queue
-    self->messages.blocks_queue = LList_construct(MessageBlock, NULL);
-    u64 message_blocks_count = self->messages.blocks_meta_list.len;
-    u64 first_block_id = 0;
-    if(message_blocks_count > MESSAGE_BLOCKS_CACHE_COUNT)
-        first_block_id = message_blocks_count - MESSAGE_BLOCKS_CACHE_COUNT;
-    for(u64 id = first_block_id; id < message_blocks_count; id++){
-        LLNode(MessageBlock)* node = LLNode_MessageBlock_createZero();
-        LList_MessageBlock_insertAfter(
-            &self->messages.blocks_queue,
-            self->messages.blocks_queue.last,
-            node
-        );
-        try_void(idb_getRow(self->messages.blocks_table, id, node->value.data, false));
-    }
-
-    if(self->messages.blocks_meta_list.len > 0){
-        MessageBlockMeta last_block_meta = self->messages.blocks_meta_list.data[self->messages.blocks_meta_list.len - 1];
-        self->messages.count = last_block_meta.first_message_id + last_block_meta.messages_count - 1;
-    }
-    else {
-        self->messages.count = 0;
-    }
-
-    success = true;
-    Return RESULT_VALUE(p, self);
-}
-
-void Channel_unloadExcessBlocks(Channel* self){
-    while(self->messages.blocks_queue.count > MESSAGE_BLOCKS_CACHE_COUNT){
-        LLNode(MessageBlock)* node = self->messages.blocks_queue.first;
-        LList_MessageBlock_detatch(&self->messages.blocks_queue, node);
-        free(node);
-    }
-}
-
-Result(void) Channel_saveMessage(Channel* self, Array(u8) message_data, u64 sender_id,
-    MessageMeta* out_message_meta, bool lock_tables)
-{
-    Deferral(4);
-
-    if(lock_tables){
-        idb_lockTable(self->messages.blocks_table);
-        idb_lockTable(self->messages.blocks_meta_table);
-        Defer(
-            idb_unlockTable(self->messages.blocks_table);
-            idb_unlockTable(self->messages.blocks_meta_table);
-        );
-    }
-
-    // create new block if message won't fit in the last existing
-    MessageBlockMeta* incomplete_block_meta = self->messages.blocks_meta_list.data + self->messages.blocks_meta_list.len;
-    u64 new_message_id = incomplete_block_meta->first_message_id + incomplete_block_meta->messages_count;
-    u32 message_size_in_block = sizeof(MessageMeta) + ALIGN_TO(message_data.len, 8);
-    if(incomplete_block_meta->data_size + message_size_in_block > MESSAGE_BLOCK_SIZE){
-        // create new MessageBlockMeta
-        incomplete_block_meta = List_MessageBlockMeta_expand(&self->messages.blocks_meta_list, 1);
-        incomplete_block_meta->first_message_id = new_message_id;
-        incomplete_block_meta->messages_count = 0;
-        incomplete_block_meta->data_size = 0;
-        // create new MessageBlock
-        LList_MessageBlock_insertAfter(
-            &self->messages.blocks_queue,
-            self->messages.blocks_queue.last, 
-            LLNode_MessageBlock_createZero());
-        // unload old blocks from cache
-        Channel_unloadExcessBlocks(self);
-    }
-    
-    // create message meta
-    out_message_meta->magic = MESSAGE_MAGIC;
-    out_message_meta->data_size = message_data.len;
-    out_message_meta->id = new_message_id;
-    out_message_meta->sender_id = sender_id;
-    DateTime_getUTC(&out_message_meta->receiving_time_utc);
-
-    // copy message data to message block
-    MessageBlock* incomplete_block = &self->messages.blocks_queue.last->value;
-    u8* data_ptr = incomplete_block->data + incomplete_block_meta->data_size;
-    memcpy(data_ptr, out_message_meta, sizeof(MessageMeta));
-    data_ptr += sizeof(MessageMeta);
-    memcpy(data_ptr, message_data.data, message_data.len);
-    incomplete_block_meta->data_size += sizeof(MessageMeta) + ALIGN_TO(message_data.len, 8);
-    incomplete_block_meta->messages_count++;
-
-    // save to DB
-    try_void(idb_pushRow(self->messages.blocks_meta_table, incomplete_block_meta, false));
-    try_void(idb_pushRow(self->messages.blocks_table, incomplete_block, false));
-
-    Return RESULT_VOID;
-}
-
-Result(void) Channel_loadMessageBlock(Channel* self, u64 fisrt_message_id, u32 count,
-    MessageBlockMeta* out_meta, NULLABLE(Array(u8)*) out_block, bool lock_tables)
-{
-    Deferral(4);
-
-    if(lock_tables){
-        idb_lockTable(self->messages.blocks_table);
-        idb_lockTable(self->messages.blocks_meta_table);
-        Defer(
-            idb_unlockTable(self->messages.blocks_table);
-            idb_unlockTable(self->messages.blocks_meta_table);
-        );
-    }
-
-    // TODO: Maybe it's better to request message block id directly? Client doesn't know how much bytes `count` messages will take, this can lead to severe lags on slow internet
-
-    // TODO: binary search in list of blocks meta
-    // TODO: return if out_block == NULL
-    // TODO: check if block is in N_LAST_BLOCKS
-    // TODO: load block
-    // TODO: insert block in queue and keep it sorted
-
-    Return RESULT_VOID;
-}

src/server/ClientConnection.c

@@ -1,11 +1,14 @@
 #include "server/server_internal.h"
-#include "network/tcp-chat-protocol/v1.h"
 
 void ClientConnection_close(ClientConnection* conn){
     if(!conn)
         return;
     EncryptedSocketTCP_destroy(&conn->sock);
     Array_u8_destroy(&conn->session_key);
+    MessageBlock_destroy(&conn->message_block);
+    Array_u8_destroy(&conn->message_content);
+    ServerQueries_free(conn->queries);
+    tsqlite_connection_close(conn->db);
     free(conn);
 }
 
@@ -21,10 +24,17 @@ Result(ClientConnection*) ClientConnection_accept(ConnectionHandlerArgs* args)
     conn->server = args->server;
     conn->client_end = args->client_end;
     conn->session_id = args->session_id;
-    conn->authorized = false;
-    conn->user_id = -1;
-    conn->session_key = Array_u8_alloc(AES_SESSION_KEY_SIZE);
+    
+    // buffers
+    MessageBlock_alloc(&conn->message_block);
+    conn->message_content = Array_u8_alloc(MESSAGE_SIZE_MAX);
+
+    // database
+    try(conn->db, p, tsqlite_connection_open(args->server->db_path));
+    try(conn->queries, p, ServerQueries_compile(conn->db));
+
     // correct session key will be received from client later
+    conn->session_key = Array_u8_alloc(AES_SESSION_KEY_SIZE);
     Array_u8_memset(&conn->session_key, 0);
     EncryptedSocketTCP_construct(&conn->sock, args->accepted_socket_tcp, NETWORK_BUFFER_SIZE, conn->session_key);
     try_void(socket_TCP_enableAliveChecks_default(args->accepted_socket_tcp));

src/server/db/Channel.c

@@ -0,0 +1,110 @@
+#include "server_db_internal.h"
+
+Result(bool) Channel_exists(ServerQueries* q, i64 id){
+    Deferral(4);
+    
+    tsqlite_statement* st = q->channels.exists;
+    Defer(tsqlite_statement_reset(st));
+    try_void(tsqlite_statement_bind_i64(st, "$id", id));
+
+    try(bool has_result, i, tsqlite_statement_step(st));
+
+    Return RESULT_VALUE(i, has_result);
+}
+
+Result(bool) Channel_createOrUpdate(ServerQueries* q, 
+    i64 id, str name, str description)
+{
+    Deferral(4);
+    try_assert(id > 0);
+    try_assert(name.len >= CHANNEL_NAME_SIZE_MIN && name.len <= CHANNEL_NAME_SIZE_MAX);
+    try_assert(description.len <= CHANNEL_DESC_SIZE_MAX);
+
+    try(bool channel_exists, i, Channel_exists(q, id));
+    tsqlite_statement* st = NULL;
+    Defer(tsqlite_statement_reset(st));
+    if(channel_exists){
+        st = q->channels.update;
+    }
+    else {
+        st = q->channels.insert;
+    }
+    try_void(tsqlite_statement_bind_i64(st, "$id", id));
+    try_void(tsqlite_statement_bind_str(st, "$name", name, NULL));
+    try_void(tsqlite_statement_bind_str(st, "$description", description, NULL));
+    try_void(tsqlite_statement_step(st));
+
+    Return RESULT_VALUE(i, !channel_exists);
+}
+
+Result(void) Channel_saveMessage(ServerQueries* q,
+    i64 channel_id, i64 sender_id, Array(u8) content,
+    DateTime* out_timestamp)
+{
+    Deferral(4);
+    try_assert(content.len >= MESSAGE_SIZE_MIN && content.len <= MESSAGE_SIZE_MAX);
+
+    tsqlite_statement* st = q->messages.insert;
+    Defer(tsqlite_statement_reset(st));
+    try_void(tsqlite_statement_bind_i64(st, "$channel_id", channel_id));
+    try_void(tsqlite_statement_bind_i64(st, "$sender_id", sender_id));
+    try_void(tsqlite_statement_bind_blob(st, "$content", content, NULL));
+
+    try(bool has_result, i, tsqlite_statement_step(st));
+    try_assert(has_result);
+
+    try(i64 message_id, i, tsqlite_statement_getResult_i64(st));
+    str timestamp_str;
+    try_void(tsqlite_statement_getResult_str(st, &timestamp_str));
+    try_void(DateTime_parse(timestamp_str.data, out_timestamp));
+
+    Return RESULT_VALUE(i, message_id);
+}
+
+Result(void) Channel_loadMessageBlock(ServerQueries* q,
+    i64 channel_id, i64 first_message_id, u32 count,
+    MessageBlock* block)
+{
+    Deferral(4);
+    if(count == 0){
+        Return RESULT_VOID;
+    }
+    try_assert(channel_id > 0);
+    try_assert(block->datum.len >= count * (sizeof(MessageMeta) + MESSAGE_SIZE_MAX));
+
+    tsqlite_statement* st = q->messages.get_block;
+    Defer(tsqlite_statement_reset(st));
+    try_void(tsqlite_statement_bind_i64(st, "$channel_id", channel_id));
+    try_void(tsqlite_statement_bind_i64(st, "$first_message_id", first_message_id));
+    try_void(tsqlite_statement_bind_i64(st, "$count", count));
+
+    MessageBlock_reset(block);
+    str tmp_str = str_null;
+    while(true){
+        try(bool has_result, i, tsqlite_statement_step(st));
+        if(!has_result)
+            break;
+        
+        // id
+        try(i64 message_id, i, tsqlite_statement_getResult_i64(st));
+        // sender_id
+        try(i64 sender_id, i, tsqlite_statement_getResult_i64(st));
+        // content
+        Array(u8) msg_content;
+        try_void(tsqlite_statement_getResult_blob(st, &msg_content));
+        // timestamp
+        try_void(tsqlite_statement_getResult_str(st, &tmp_str));
+        DateTime timestamp;
+        try_void(DateTime_parse(tmp_str.data, &timestamp));
+        
+        MessageMeta msg_meta = MessageMeta_construct(
+            msg_content.len,
+            message_id,
+            sender_id,
+            timestamp);
+        try(bool write_success, u, MessageBlock_writeMessage(block, &msg_meta, msg_content));
+        try_assert(write_success == true);
+    }
+
+    Return RESULT_VOID;
+}

src/server/db/User.c

@@ -0,0 +1,50 @@
+#include "server_db_internal.h"
+
+Result(i64) User_findByUsername(ServerQueries* q, str username){
+    Deferral(4);
+
+    tsqlite_statement* st = q->users.find_by_username;
+    Defer(tsqlite_statement_reset(st));
+    try_void(tsqlite_statement_bind_str(st, "$username", username, NULL));
+    
+    try(bool has_result, i, tsqlite_statement_step(st));
+    i64 user_id = 0;
+    if(has_result){
+        try(user_id, i, tsqlite_statement_getResult_i64(st));
+        try_assert(user_id > 0);
+    }
+
+    Return RESULT_VALUE(i, user_id);
+}
+
+Result(i64) User_register(ServerQueries* q, str username, Array(u8) token){
+    Deferral(4);
+    try_assert(username.len >= USERNAME_SIZE_MIN && username.len <= USERNAME_SIZE_MAX);
+    try_assert(token.len == PASSWORD_HASH_SIZE)
+
+    tsqlite_statement* st = q->users.insert;
+    Defer(tsqlite_statement_reset(st));
+    try_void(tsqlite_statement_bind_str(st, "$username", username, NULL));
+    try_void(tsqlite_statement_bind_blob(st, "$token", token, NULL));
+
+    try(bool has_result, i, tsqlite_statement_step(st));
+    try_assert(has_result);
+    try(i64 user_id, i, tsqlite_statement_getResult_i64(st));
+    try_assert(user_id > 0);
+
+    Return RESULT_VALUE(i, user_id);
+}
+
+Result(bool) User_tryAuthorize(ServerQueries* q, u64 id, Array(u8) token){
+    Deferral(4);
+    try_assert(token.len == PASSWORD_HASH_SIZE)
+
+    tsqlite_statement* st = q->users.compare_token;
+    Defer(tsqlite_statement_reset(st));
+    try_void(tsqlite_statement_bind_i64(st, "$id", id));
+    try_void(tsqlite_statement_bind_blob(st, "$token", token, NULL));
+
+    try(bool has_result, i, tsqlite_statement_step(st));
+
+    Return RESULT_VALUE(i, has_result);
+}

src/server/db/server_db.c

@@ -0,0 +1,153 @@
+#include "server_db_internal.h"
+#include "tlibc/filesystem.h"
+
+Result(tsqlite_connection*) ServerDatabase_open(cstr file_path){
+    Deferral(64);
+
+    try_void(dir_createParent(file_path));
+    try(tsqlite_connection* db, p, tsqlite_connection_open(file_path));
+    bool success = false;
+    Defer(if(!success) tsqlite_connection_close(db));
+
+    ///////////////////////////////////////////////////////////////////////////
+    //                               CHANNELS                                //
+    ///////////////////////////////////////////////////////////////////////////
+    try(tsqlite_statement* create_table_channels, p, tsqlite_statement_compile(db, STR(
+        "CREATE TABLE IF NOT EXISTS channels (\n"
+        "   id INTEGER PRIMARY KEY AUTOINCREMENT,\n"
+        "   name VARCHAR NOT NULL,\n"
+        "   description VARCHAR NOT NULL\n"
+        ");"
+    )));
+    Defer(tsqlite_statement_free(create_table_channels));
+    try_void(tsqlite_statement_step(create_table_channels));
+
+    
+    ///////////////////////////////////////////////////////////////////////////
+    //                               MESSAGES                                //
+    ///////////////////////////////////////////////////////////////////////////
+    try(tsqlite_statement* create_table_messages, p, tsqlite_statement_compile(db, STR(
+        "CREATE TABLE IF NOT EXISTS messages (\n"
+        "   id INTEGER PRIMARY KEY AUTOINCREMENT,\n"
+        "   channel_id INTEGER NOT NULL REFERENCES channels(id),\n"
+        "   sender_id INTEGER NOT NULL REFERENCES users(id),\n"
+        "   content BLOB NOT NULL,\n"
+        "   timestamp DATETIME NOT NULL DEFAULT (\n"
+        "       strftime('"MESSAGE_TIMESTAMP_FMT_SQL"', 'now', 'utc', 'subsecond')\n"
+        "   )\n"
+        ");"
+    )));
+    Defer(tsqlite_statement_free(create_table_messages));
+    try_void(tsqlite_statement_step(create_table_messages));
+
+    ///////////////////////////////////////////////////////////////////////////
+    //                                 USERS                                 //
+    ///////////////////////////////////////////////////////////////////////////
+    try(tsqlite_statement* create_table_users, p, tsqlite_statement_compile(db, STR(
+        "CREATE TABLE IF NOT EXISTS users (\n"
+        "   id INTEGER PRIMARY KEY AUTOINCREMENT,\n"
+        "   username VARCHAR NOT NULL,\n"
+        "   token BLOB NOT NULL,\n"
+        "   registration_time DATETIME NOT NULL DEFAULT (\n"
+        "       strftime('"MESSAGE_TIMESTAMP_FMT_SQL"', 'now', 'utc', 'subsecond')\n"
+        "   )\n"
+        ");"
+    )));
+    Defer(tsqlite_statement_free(create_table_users));
+    try_void(tsqlite_statement_step(create_table_users));
+
+    try(tsqlite_statement* create_index_username, p, tsqlite_statement_compile(db, STR(
+        "CREATE UNIQUE INDEX IF NOT EXISTS idx_users_username ON users(username);"
+    )));
+    Defer(tsqlite_statement_free(create_index_username));
+    try_void(tsqlite_statement_step(create_index_username));
+
+    success = true;
+    Return RESULT_VALUE(p, db);
+}
+
+
+
+void ServerQueries_free(ServerQueries* q){
+    if(!q)
+        return;
+    
+    tsqlite_statement_free(q->channels.insert);
+    tsqlite_statement_free(q->channels.update);
+    tsqlite_statement_free(q->channels.exists);
+
+    tsqlite_statement_free(q->messages.insert);
+    tsqlite_statement_free(q->messages.get_block);
+    
+    tsqlite_statement_free(q->users.insert);
+    tsqlite_statement_free(q->users.find_by_username);
+    tsqlite_statement_free(q->users.compare_token);
+
+    free(q);
+}
+
+Result(ServerQueries*) ServerQueries_compile(tsqlite_connection* db){
+    Deferral(4);
+
+    ServerQueries* q = (ServerQueries*)malloc(sizeof(*q));
+    zeroStruct(q);
+    bool success = false;
+    Defer(if(!success) ServerQueries_free(q));
+
+    ///////////////////////////////////////////////////////////////////////////
+    //                               CHANNELS                                //
+    ///////////////////////////////////////////////////////////////////////////
+    try(q->channels.insert, p, tsqlite_statement_compile(db, STR(
+        "INSERT INTO\n"
+        "channels (id, name, description)\n"
+        "VALUES ($id, $name, $description);"
+    )));
+
+    try(q->channels.exists, p, tsqlite_statement_compile(db, STR(
+        "SELECT 1 FROM channels WHERE id = $id;"
+    )));
+    
+    try(q->channels.update, p, tsqlite_statement_compile(db, STR(
+        "UPDATE channels\n"
+        "SET name = $name, description = $description\n"
+        "WHERE id = $id;"
+    )));
+
+    ///////////////////////////////////////////////////////////////////////////
+    //                               MESSAGES                                //
+    ///////////////////////////////////////////////////////////////////////////
+    try(q->messages.insert, p, tsqlite_statement_compile(db, STR(
+        "INSERT INTO\n"
+        "messages (channel_id, sender_id, content)\n"
+        "VALUES ($channel_id, $sender_id, $content)\n"
+        "RETURNING id, timestamp;"
+    )));
+
+    try(q->messages.get_block, p, tsqlite_statement_compile(db, STR(
+        "SELECT id, sender_id, content, timestamp FROM messages\n"
+        "WHERE id >= $first_message_id\n"
+        "AND channel_id = $channel_id\n"
+        "LIMIT $count;"
+    )));
+
+    ///////////////////////////////////////////////////////////////////////////
+    //                                 USERS                                 //
+    ///////////////////////////////////////////////////////////////////////////
+    try(q->users.insert, p, tsqlite_statement_compile(db, STR(
+        "INSERT INTO\n"
+        "users (username, token)\n"
+        "VALUES ($username, $token)\n"
+        "RETURNING id, registration_time;"
+    )));
+
+    try(q->users.find_by_username, p, tsqlite_statement_compile(db, STR(
+        "SELECT id FROM users WHERE username = $username;"
+    )));
+
+    try(q->users.compare_token, p, tsqlite_statement_compile(db, STR(
+        "SELECT 1 FROM users WHERE id = $id AND token = $token;"
+    )));
+
+    success = true;
+    Return RESULT_VALUE(p, q);
+}

src/server/db/server_db.h

@@ -0,0 +1,39 @@
+#pragma once
+#include "tcp-chat.h"
+#include "tsqlite.h"
+#include "network/tcp-chat-protocol/v1.h"
+
+/// @brief open DB and create tables
+Result(tsqlite_connection*) ServerDatabase_open(cstr file_path);
+
+typedef struct ServerQueries ServerQueries;
+Result(ServerQueries*) ServerQueries_compile(tsqlite_connection* db);
+void ServerQueries_free(ServerQueries* self);
+
+
+Result(bool) Channel_exists(ServerQueries* q, i64 id);
+
+/// @return true if new row was created
+Result(bool) Channel_createOrUpdate(ServerQueries* q,
+    i64 id, str name, str description);
+
+/// @return new message id
+Result(i64) Channel_saveMessage(ServerQueries* q,
+    i64 channel_id, i64 sender_id, Array(u8) content,
+    DateTime* out_timestamp_utc);
+
+/// @brief try to find count messages with id >= first_message_id
+/// @param dst_block writes messages here. messages_count can be 0 if no messages were found
+Result(void) Channel_loadMessageBlock(ServerQueries* q,
+    i64 channel_id, i64 first_message_id, u32 count,
+    MessageBlock* dst_block);
+
+
+/// @return existing user id or 0
+Result(i64) User_findByUsername(ServerQueries* q, str username);
+
+/// @return new user id
+Result(i64) User_register(ServerQueries* q, str username, Array(u8) token);
+
+/// @return true for successful authorization
+Result(bool) User_tryAuthorize(ServerQueries* q, u64 id, Array(u8) token);

src/server/db/server_db_internal.h

@@ -0,0 +1,27 @@
+#pragma once
+#include "server_db.h"
+
+typedef struct ServerQueries {
+    struct {
+        /* ($id, $name, $description) -> void */
+        tsqlite_statement* insert;
+        /* ($id, $name, $description) -> void */
+        tsqlite_statement* update;
+        /* ($id) -> 1 or nothing */
+        tsqlite_statement* exists;
+    } channels;
+    struct {
+        /* ($channel_id, $sender_id, $content) -> (id, timestamp) */
+        tsqlite_statement* insert; 
+        /* ($channel_id, $first_message_id, $count) -> [(id, sender_id, content, timestamp)] */
+        tsqlite_statement* get_block;
+    } messages;
+    struct {
+        /* ($username, $token) -> (id, registration_time) */
+        tsqlite_statement* insert;
+        /* ($username) -> (id) */
+        tsqlite_statement* find_by_username;
+        /* ($id, $token) -> 1 or nothing */
+        tsqlite_statement* compare_token;
+    } users;
+} ServerQueries;

src/server/responses/GetMessageBlock.c

@@ -21,27 +21,36 @@ declare_RequestHandler(GetMessageBlock)
         Return RESULT_VOID;
     }
     
-    // get message block from channel
-    Channel* ch = Server_tryGetChannel(conn->server, req.channel_id);
-    if(ch == NULL){
+    // validate messages_count
+    if(req.messages_count < 1 || req.messages_count > MESSAGE_BLOCK_COUNT_MAX){
+        try_void(sendErrorMessage(log_ctx, conn, res_head,
+            LogSeverity_Warn, STR("invalid message count in request") ));
+        Return RESULT_VOID;
+    }
+
+    // validate channel id
+    try(bool channel_exists, i, Channel_exists(conn->queries, req.channel_id));
+    if(!channel_exists){
         try_void(sendErrorMessage(log_ctx, conn, res_head,
             LogSeverity_Warn, STR("invalid channel id") ));
         Return RESULT_VOID;
     }
-    MessageBlockMeta meta;
-    Array(u8) block_data;
-    try_void(Channel_loadMessageBlock(ch, req.first_message_id, req.messages_count, 
-        &meta, &block_data, true));
-    Defer(Array_u8_destroy(&block_data));
+
+    // get message block from channel
+    try_void(Channel_loadMessageBlock(conn->queries, 
+        req.channel_id, req.first_message_id, req.messages_count, 
+        &conn->message_block));
 
     // send response
     GetMessageBlockResponse res;
     GetMessageBlockResponse_construct(&res, res_head, 
-        meta.first_message_id, meta.messages_count, meta.data_size);
+        conn->message_block.messages_count, conn->message_block.offset);
     try_void(EncryptedSocketTCP_sendStruct(&conn->sock, res_head));
     try_void(EncryptedSocketTCP_sendStruct(&conn->sock, &res));
-    if(block_data.len != 0){
-        try_void(EncryptedSocketTCP_send(&conn->sock, block_data));
+    if(conn->message_block.offset != 0){
+        try_void(EncryptedSocketTCP_send(&conn->sock, 
+            Array_u8_sliceTo(conn->message_block.datum, conn->message_block.offset))
+        );
     }
 
     Return RESULT_VOID;

src/server/responses/Login.c

@@ -22,8 +22,8 @@ declare_RequestHandler(Login)
     }
 
     // validate username
-    str username_str = str_null;
-    str name_error_str = validateUsername_cstr(req.username, &username_str);
+    str username = str_null;
+    str name_error_str = validateUsername_cstr(req.username, &username);
     if(name_error_str.data){
         Defer(str_destroy(name_error_str));
         try_void(sendErrorMessage(log_ctx, conn, res_head,
@@ -31,42 +31,28 @@ declare_RequestHandler(Login)
         Return RESULT_VOID;
     }
 
-    // lock users cache
-    idb_lockTable(srv->users.table);
-    bool unlocked_users_cache_mutex = false;
-    Defer(
-        if(!unlocked_users_cache_mutex)
-            idb_unlockTable(srv->users.table)
-    );
-    
-    // try get id from name cache
-    u64* id_ptr = HashMap_tryGetPtr(&srv->users.name_id_map, username_str);
-    if(id_ptr == NULL){
+    // get user by id
+    try(u64 user_id, i, User_findByUsername(conn->queries, username));
+    if(user_id == 0){
         try_void(sendErrorMessage(log_ctx, conn, res_head,
             LogSeverity_Warn, STR("Username is not registered") ));
         Return RESULT_VOID;
     }
-    u64 user_id = *id_ptr;
-
-    // get user by id
-    try_assert(user_id < srv->users.list.len);
-    UserInfo* u = srv->users.list.data + user_id;
 
+    // TODO: get user token
+    Array(u8) token = Array_u8_construct(req.token, sizeof(req.token));
+    try(bool authorized, i, User_tryAuthorize(conn->queries, user_id, token));
     // validate token hash
-    if(memcmp(req.token, u->token, sizeof(req.token)) != 0){
+    if(!authorized){
         try_void(sendErrorMessage(log_ctx, conn, res_head,
             LogSeverity_Warn, STR("wrong password") ));
         Return RESULT_VOID;
     }
 
-    // manually unlock mutex
-    idb_unlockTable(srv->users.table);
-    unlocked_users_cache_mutex = true;
-
     // authorize
     conn->authorized = true;
     conn->user_id = user_id;
-    logInfo("authorized user '%s'", username_str.data);
+    logInfo("authorized user '%s' with id "FMT_i64, username.data, user_id);
 
     // send response
     LoginResponse res;

src/server/responses/Register.c

@@ -22,8 +22,8 @@ declare_RequestHandler(Register)
     }
 
     // validate username
-    str username_str = str_null;
-    str name_error_str = validateUsername_cstr(req.username, &username_str);
+    str username = str_null;
+    str name_error_str = validateUsername_cstr(req.username, &username);
     if(name_error_str.data){
         Defer(str_destroy(name_error_str));
         try_void(sendErrorMessage(log_ctx, conn, res_head, 
@@ -31,46 +31,19 @@ declare_RequestHandler(Register)
         Return RESULT_VOID;
     }
 
-    // lock users cache
-    idb_lockTable(srv->users.table);
-    bool unlocked_users_cache_mutex = false;
-    // unlock mutex on error catch
-    Defer(
-        if(!unlocked_users_cache_mutex)
-            idb_unlockTable(srv->users.table)
-    );
-
     // check if name is taken
-    if(HashMap_tryGetPtr(&srv->users.name_id_map, username_str) != NULL){
+    try(u64 user_id, i, User_findByUsername(conn->queries, username));
+    if(user_id != 0){
         try_void(sendErrorMessage(log_ctx, conn, res_head,
-            LogSeverity_Warn, STR("Username already exists") ));
+            LogSeverity_Warn, STR("Username is already taken") ));
         Return RESULT_VOID;
     }
     
-    // initialize new user
-    UserInfo user;
-    zeroStruct(&user);
-
-    user.name_len = username_str.len;
-    memcpy(user.name, username_str.data, user.name_len);
-
-    memcpy(user.token, req.token, sizeof(req.token));
-    
-    DateTime_getUTC(&user.registration_time_utc);
-    
-    // save new user to db and cache
-    try(u64 user_id, u, 
-        idb_pushRow(srv->users.table, &user, false)
-    );
-    try_assert(user_id == srv->users.list.len);
-    List_UserInfo_pushMany(&srv->users.list, &user, 1);
-    try_assert(HashMap_tryPush(&srv->users.name_id_map, username_str, &user_id));
-    
-    // manually unlock mutex
-    idb_unlockTable(srv->users.table);
-    unlocked_users_cache_mutex = true;
-
-    logInfo("registered user '%s'", username_str.data);
+    // register new user
+    Array(u8) token = Array_u8_construct(req.token, sizeof(req.token));
+    try(user_id, i, User_register(conn->queries, username, token));
+    logInfo("registered user '"FMT_str"' with id "FMT_i64, 
+        str_unwrap(username), user_id);
 
     // send response
     RegisterResponse res;

src/server/responses/SendMessage.c

@@ -21,6 +21,7 @@ declare_RequestHandler(SendMessage)
         Return RESULT_VOID;
     }
 
+    // validate content size
     if(req.data_size < MESSAGE_SIZE_MIN || req.data_size > MESSAGE_SIZE_MAX){
         try_void(sendErrorMessage(log_ctx, conn, res_head,
             LogSeverity_Warn, STR("invalid message size") ));
@@ -29,24 +30,26 @@ declare_RequestHandler(SendMessage)
     }
     
     // receive message data
-    Array(u8) message_data = Array_u8_alloc(req.data_size);
-    try_void(EncryptedSocketTCP_recv(&conn->sock, message_data, SocketRecvFlag_WholeBuffer));
+    try_void(EncryptedSocketTCP_recv(&conn->sock, conn->message_content, SocketRecvFlag_WholeBuffer));
     
-    // save message to channel
-    Channel* ch = Server_tryGetChannel(conn->server, req.channel_id);
-    if(ch == NULL){
+    // validate channel id
+    try(bool channel_exists, i, Channel_exists(conn->queries, req.channel_id));
+    if(!channel_exists){
         try_void(sendErrorMessage(log_ctx, conn, res_head,
             LogSeverity_Warn, STR("invalid channel id") ));
         Return RESULT_VOID;
     }
-    MessageMeta message_meta;
-    try_void(Channel_saveMessage(ch, message_data, conn->user_id, 
-        &message_meta, true));
+
+    // save message to channel
+    DateTime timestamp;
+    try(i64 message_id, i, Channel_saveMessage(conn->queries,
+        req.channel_id, conn->user_id, conn->message_content, 
+        &timestamp));
 
     // send response
     SendMessageResponse res;
     SendMessageResponse_construct(&res, res_head, 
-        message_meta.id, message_meta.receiving_time_utc);
+        message_id, timestamp);
     try_void(EncryptedSocketTCP_sendStruct(&conn->sock, res_head));
     try_void(EncryptedSocketTCP_sendStruct(&conn->sock, &res));
 

src/server/responses/responses.h

@@ -1,8 +1,6 @@
 #pragma once
-#include "network/tcp-chat-protocol/v1.h"
 #include "server/server_internal.h"
 
-
 Result(void) sendErrorMessage(
     cstr log_ctx, ClientConnection* conn, PacketHeader* res_head, 
     LogSeverity log_severity, str msg);

src/server/responses/send_error.c

@@ -9,7 +9,7 @@ Result(void) sendErrorMessage(
     cstr log_ctx, ClientConnection* conn, PacketHeader* res_head, 
     LogSeverity log_severity, str msg)
 {
-    Deferral(1);
+    Deferral(4);
 
     //limit ErrorMessage size to fit into EncryptedSocketTCP.internal_buffer_size
     if(msg.len > ERROR_MESSAGE_MAX_SIZE)
@@ -44,7 +44,7 @@ Result(void) sendErrorMessage_f(
     ClientConnection* conn, PacketHeader* res_head, 
     LogSeverity log_severity, cstr format, ...)
 {
-    Deferral(1);
+    Deferral(4);
 
     va_list argv;
     va_start(argv, format);

src/server/server.c

@@ -1,10 +1,6 @@
 #include <pthread.h>
-#include "tlibc/filesystem.h"
 #include "tlibc/time.h"
-#include "tlibc/base64.h"
-#include "tlibc/algorithms.h"
 #include "server/server_internal.h"
-#include "network/tcp-chat-protocol/v1.h"
 #include "server/responses/responses.h"
 #include "tlibtoml.h"
 
@@ -20,17 +16,9 @@ void Server_free(Server* self){
     RSA_destroyPrivateKey(&self->rsa_sk);
     RSA_destroyPublicKey(&self->rsa_pk);
 
-    idb_close(self->db);
-
-    List_UserInfo_destroy(&self->users.list);
-    HashMap_destroy(&self->users.name_id_map);
-
-    for(u32 i = 0; i < self->channels.list.len; i++){
-        Channel_free(self->channels.list.data[i]);
-    }
-    List_ChannelPtr_destroy(&self->channels.list);
-    HashMap_destroy(&self->channels.name_id_map);
-
+    free(self->db_path);
+    ServerQueries_free(self->queries);
+    tsqlite_connection_close(self->db);
 
     free(self);
 }
@@ -58,78 +46,51 @@ Result(Server*) Server_create(str config_file_content, cstr config_file_name,
     try(TomlTable* config_top, p, toml_load_str_filename(config_file_content, config_file_name));
     Defer(TomlTable_free(config_top));
 
+    // [server]
     try(TomlTable* config_server, p, TomlTable_get_table(config_top, STR("server")))
-    // parse name
+    // name
     try(str* v_name, p, TomlTable_get_str(config_server, STR("name")));
     self->name = str_copy(*v_name);
 
-    // parse description
+    // description
     try(str* v_desc, p, TomlTable_get_str(config_server, STR("description")));
     self->description = str_copy(*v_desc);
 
-    // parse local_address
+    // local_address
     try(str* v_local_address, p, TomlTable_get_str(config_server, STR("local_address")));
     try_assert(v_local_address->isZeroTerminated);
     try_void(EndpointIPv4_parse(v_local_address->data, &self->local_end));
     
-    // parse landing_channel_id
+    // landing_channel_id
     try(i64 v_landing_channel_id, i, TomlTable_get_integer(config_server, STR("landing_channel_id")));
     self->landing_channel_id = v_landing_channel_id;
 
+    // [keys]
     try(TomlTable* config_keys, p, TomlTable_get_table(config_top, STR("keys")))
-    // parse rsa_private_key
+    // rsa_private_key
     try(str* v_rsa_sk, p, TomlTable_get_str(config_keys, STR("rsa_private_key")));
     try_assert(v_rsa_sk->isZeroTerminated);
     try_void(RSA_parsePrivateKey_base64(v_rsa_sk->data, &self->rsa_sk));
 
-    // parse rsa_public_key
+    // rsa_public_key
     try(str* v_rsa_pk, p, TomlTable_get_str(config_keys, STR("rsa_public_key")));
     try_assert(v_rsa_pk->isZeroTerminated);
     try_void(RSA_parsePublicKey_base64(v_rsa_pk->data, &self->rsa_pk));
     
+    // [db]
     try(TomlTable* config_db, p, TomlTable_get_table(config_top, STR("database")))
-    // parse db_aes_key
-    try(str* v_db_aes_key, p, TomlTable_get_str(config_db, STR("aes_key")));
-    str db_aes_key_s = *v_db_aes_key;
-    Array(u8) db_aes_key = Array_u8_alloc(base64_decodedSize(db_aes_key_s.data, db_aes_key_s.len));
-    Defer(free(db_aes_key.data));
-    base64_decode(db_aes_key_s.data, db_aes_key_s.len, db_aes_key.data);
-
-    // parse db_dir
-    try(str* v_db_dir, p, TomlTable_get_str(config_db, STR("dir")));
+    // path
+    try(str* v_db_path, p, TomlTable_get_str(config_db, STR("path")));
+    self->db_path = str_copy(*v_db_path).data;
 
     // open DB
-    try(self->db, p, idb_open(*v_db_dir, db_aes_key));
+    logInfo("loading database '%s'", self->db_path);
+    try(self->db, p, ServerDatabase_open(self->db_path));
+    try(self->queries, p, ServerQueries_compile(self->db));
 
-    // build users cache
-    logInfo("loading users...");
-    try(self->users.table, p, 
-        idb_getOrCreateTable(self->db, str_null, STR("users"), sizeof(UserInfo), false)
-    );
-
-    // load whole users table to list
-    try_void(
-        idb_createListFromTable(self->users.table, (void*)&self->users.list, false)
-    );
-
-    // build name-id map
-    try(u64 users_count, u, idb_getRowCount(self->users.table, false));
-    HashMap_construct(&self->users.name_id_map, u64, NULL);
-    for(u64 id = 0; id < users_count; id++){
-        UserInfo* user = self->users.list.data + id;
-        str key = str_construct(user->name, user->name_len, true);
-        if(!HashMap_tryPush(&self->users.name_id_map, key, &id)){
-            Return RESULT_ERROR_FMT("duplicate user name '"FMT_str"'", str_expand(key));
-        }
-    }
-    logInfo("loaded "FMT_u64" users", users_count);
-
-    // parse channels
+    // [channels]
     logDebug("loading channels...");
-    HashMap_construct(&self->channels.name_id_map, u64, NULL);
-    self->channels.list = List_ChannelPtr_alloc(32);
     try(TomlTable* config_channels, p, TomlTable_get_table(config_top, STR("channels")));
-    
     HashMapIter channels_iter = HashMapIter_create(config_channels);
     while(HashMapIter_moveNext(&channels_iter)){
         HashMapKeyValue kv;
@@ -140,26 +101,15 @@ Result(Server*) Server_create(str config_file_content, cstr config_file_name,
         if(val->type != TLIBTOML_TABLE)
             continue;
         
-        logInfo("loading channel '"FMT_str"'", str_expand(name))
+        logInfo("loading channel '"FMT_str"'", str_unwrap(name))
         TomlTable* config_channel = val->table;
-        try(u64 id, u, TomlTable_get_integer(config_channel, STR("id")));
+        try(i64 id, u, TomlTable_get_integer(config_channel, STR("id")));
         try(str* v_ch_desc, p, TomlTable_get_str(config_channel, STR("description")))
         str description = *v_ch_desc;
 
-        if(!HashMap_tryPush(&self->channels.name_id_map, name, &id)){
-            Return RESULT_ERROR_FMT("duplicate channel '"FMT_str"'", str_expand(name));
+        try_void(Channel_createOrUpdate(self->queries, id, name, description));
     }
 
-        logDebug("loading messages...");
-        try(Channel* channel, p, Channel_create(id, name, description, self->db, false));
-        logDebug("loaded "FMT_u64" messages", channel->messages.count);
-        List_ChannelPtr_push(&self->channels.list, channel);
-    }
-    logDebug("loaded "FMT_u32" channels", self->channels.list.len);
-    // sort channels list by id
-    for(u32 i = 0; i < self->channels.list.len; i++);
-    insertionSort_inline(self->channels.list.data, self->channels.list.len, ->id);
-
     success = true;
     Return RESULT_VALUE(p, self);
 }
@@ -184,7 +134,7 @@ Result(void) Server_run(Server* server){
     Defer(free(local_end_str.data));
     logInfo("server is listening at %s", local_end_str.data);
 
-    u64 session_id = 1;
+    i64 session_id = 1;
     while(true){
         ConnectionHandlerArgs* args = (ConnectionHandlerArgs*)malloc(sizeof(ConnectionHandlerArgs));
         args->server = server;
@@ -201,16 +151,6 @@ Result(void) Server_run(Server* server){
     Return RESULT_VOID;
 }
 
-Channel* Server_tryGetChannel(Server* self, u64 id){
-    i32 index;
-    binarySearch_inline(self->channels.list.data, self->channels.list.len, id, ->id, index);
-    if(index == -1){
-        return NULL;
-    }
-    Channel* channel = self->channels.list.data[index];
-    return channel;
-}
-
 static void* handleConnection(void* _args){
     ConnectionHandlerArgs* args = (ConnectionHandlerArgs*)_args;
     Server* server = args->server;

src/server/server_internal.h

@@ -1,56 +1,13 @@
 #pragma once
-#include "tlibc/collections/HashMap.h"
-#include "tlibc/collections/List.h"
-#include "tlibc/collections/LList.h"
-#include "tcp-chat/tcp-chat.h"
-#include "tcp-chat/server.h"
+#include "tcp-chat.h"
 #include "cryptography/AES.h"
 #include "cryptography/RSA.h"
 #include "network/encrypted_sockets.h"
-#include "db/idb.h"
-#include "db/tables.h"
+#include "network/tcp-chat-protocol/v1.h"
+#include "db/server_db.h"
 
 typedef struct ClientConnection ClientConnection;
 
-List_declare(UserInfo);
-List_declare(MessageBlockMeta);
-LList_declare(MessageBlock);
-
-#define MESSAGE_BLOCKS_CACHE_COUNT 50
-
-typedef struct Channel {
-    u64 id;
-    str name;
-    str description;
-    struct {
-        u64 count;
-        Table* blocks_table;
-        Table* blocks_meta_table;
-        List(MessageBlockMeta) blocks_meta_list; // index is id
-        // last MESSAGE_BLOCKS_CACHE_COUNT MessageBlocks, ascending
-        // new messages are written to the last block
-        LList(MessageBlock) blocks_queue;
-    } messages;
-} Channel;
-
-typedef Channel* ChannelPtr;
-List_declare(ChannelPtr);
-
-Result(Channel*) Channel_create(u64 id, str name, str description,
-    IncrementalDB* db, bool lock_db);
-
-void Channel_free(Channel* self);
-
-Result(void) Channel_saveMessage(Channel* self, Array(u8) message_data, u64 sender_id,
-    MessageMeta* out_message_meta, bool lock_tables);
-
-/// @brief try to find `count` messages starting from `fisrt_message_id`
-/// @param out_meta information about found messages, .count can be 0 if no messages found
-/// @param out_block allocates buffer on heap and copies them there, .len can be 0 if no messages found
-Result(void) Channel_loadMessageBlock(Channel* self, u64 fisrt_message_id, u32 count,
-    MessageBlockMeta* out_meta, NULLABLE(Array(u8)*) out_block, bool lock_tables);
-
-
 typedef struct Server {
     /* from constructor */
     void* logger;
@@ -59,42 +16,41 @@ typedef struct Server {
     /* from config */
     str name;
     str description;
-    u64 landing_channel_id;
+    i64 landing_channel_id;
     EndpointIPv4 local_end;
     br_rsa_private_key rsa_sk;
     br_rsa_public_key rsa_pk;
 
     /* database and cache*/
-    IncrementalDB* db;
-    struct {
-        Table* table;
-        List(UserInfo) list; // index is id
-        HashMap(u64) name_id_map;
-    } users;
-    struct {
-        List(ChannelPtr) list;
-        HashMap(u64) name_id_map;
-    } channels;
+    char* db_path;
+    tsqlite_connection* db;
+    ServerQueries* queries; /* for server listener thread only */
 } Server;
 
-Channel* Server_tryGetChannel(Server* self, u64 id);
-
 
 typedef struct ClientConnection {
     Server* server;
-    u64 session_id;
+    i64 session_id;
     EndpointIPv4 client_end;
     Array(u8) session_key;
     EncryptedSocketTCP sock;
     bool authorized;
-    u64 user_id; // -1 for unauthorized
+    i64 user_id; // 0 for unauthorized
+
+    /* buffers */
+    MessageBlock message_block; // requested message block
+    Array(u8) message_content;  // sent message
+
+    /* database */
+    tsqlite_connection* db;
+    ServerQueries* queries;
 } ClientConnection;
 
 typedef struct ConnectionHandlerArgs {
     Server* server;
     Socket accepted_socket_tcp;
     EndpointIPv4 client_end;
-    u64 session_id;
+    i64 session_id;
 } ConnectionHandlerArgs;
 
 Result(ClientConnection*) ClientConnection_accept(ConnectionHandlerArgs* args);

tcp-chat-server.toml.default

@@ -5,16 +5,17 @@ description = """\
     Qqqqq...\
     """
 local_address = '127.0.0.1:9988'
-landing_channel_id = 0
+landing_channel_id = 1
 
 # do not create channels with the same id
 [channels.general]
-id = 0
+id = 1
 description = "a text channel"
 
 [database]
-dir = 'server-db'
-aes_key = '<generate with './tcp-chat --random-bytes-base64 32'>'
+path = 'tcp-chat-server/server.sqlite'
+# on windows use backslashes
+# path = 'tcp-chat-server\server.sqlite'
 
 [keys]
 rsa_private_key = '<generate with './tcp-chat --rsa-gen-random'>'