#!/usr/bin/env bash
CBUILD_VERSION=2.3.1

PROJECT="tcp-chat"
CMP_C="gcc"
CMP_CPP="g++"
STD_C="c99"
STD_CPP="c++11"
WARN_C="-Wall -Wextra
    -Wduplicated-branches
    -Wduplicated-cond
    -Wformat=2
    -Wmissing-include-dirs
    -Wshadow
    -Werror=return-type
    -Werror=pointer-arith
    -Werror=init-self
    -Werror=incompatible-pointer-types"
WARN_CPP="$WARN_C"
SRC_C="$(find src -name '*.c')"
SRC_CPP="$(find src -name '*.cpp')"

# Directory with dependency configs.
# See cbuild/example_dependency_configs
DEPENDENCY_CONFIGS_DIR='dependencies'
# List of dependency config files in DEPENDENCY_CONFIGS_DIR separated by space.
ENABLED_DEPENDENCIES='tlibc bearssl'

# OBJDIR structure:
#  ├── objects/      - Compiled object files. Cleans on each call of build task
#  ├── static_libs/  - Symbolic links to static libraries used by linker. Cleans on each call of build task.
#  ├── static_libs/  - Symbolic links to dynamic libraries used by linker. Cleans on each call of build task.
#  └── profile/      - gcc *.gcda profiling info files
OBJDIR="obj"
OUTDIR="bin"
STATIC_LIB_FILE="$PROJECT.a"

INCLUDE="-Isrc -I$DEPENDENCIES_DIR/BearSSL/inc -I$DEPENDENCIES_DIR/tlibc/include"

# OS-specific options
case "$OS" in
    WINDOWS)
        EXEC_FILE="$PROJECT.exe"
        SHARED_LIB_FILE="$PROJECT.dll"
        INCLUDE="$INCLUDE "
        LINKER_LIBS="-static -lpthread -lws2_32"
        ;;
    LINUX)
        EXEC_FILE="$PROJECT"
        SHARED_LIB_FILE="$PROJECT.so"
        INCLUDE="$INCLUDE "
        LINKER_LIBS=""
        ;;
    *)
        error "operating system $OS has no configuration variants"
        ;;
esac

# TASKS
case "$TASK" in
    # creates executable using profiling info if it exists
    build_exec)
        # -flto applies more optimizations across object files
        # -flto=auto is needed to multithreaded copilation
        # -fuse-linker-plugin is required to use static libs with lto
        # -fprofile-use enables compiler to use profiling info files to optimize executable
        # -fprofile-prefix-path sets path where profiling info about objects are be saved
        # -fdata-sections -ffunction-sections -Wl,--gc-sections  removes unused code
        C_ARGS="-O2 -flto=auto -fuse-linker-plugin -fprofile-use -fprofile-prefix-path=$(realpath $OBJDIR)/objects -fdata-sections -ffunction-sections -Wl,--gc-sections"
        CPP_ARGS="$C_ARGS"
        LINKER_ARGS="$CPP_ARGS $LINKER_LIBS"
        PRE_TASK_SCRIPT=""
        TASK_SCRIPT="@cbuild/default_tasks/build_exec.sh"
        POST_TASK_SCRIPT="@cbuild/default_tasks/strip_exec.sh"
        ;;
    # creates executable with debug info and no optimizations
    build_exec_dbg)
        C_ARGS="-O0 -g3"
        CPP_ARGS="$C_ARGS"
        LINKER_ARGS="$CPP_ARGS $LINKER_LIBS"
        PRE_TASK_SCRIPT=""
        TASK_SCRIPT="@cbuild/default_tasks/build_exec.sh"
        POST_TASK_SCRIPT=""
        ;;
    # creates shared library
    build_shared_lib)
        C_ARGS="-O2 -fpic -flto -shared"
        CPP_ARGS="$C_ARGS"
        LINKER_ARGS="$CPP_ARGS $LINKER_LIBS -Wl,-soname,$SHARED_LIB_FILE"
        PRE_TASK_SCRIPT=""
        TASK_SCRIPT="@cbuild/default_tasks/build_shared_lib.sh"
        POST_TASK_SCRIPT=""
        ;;
    # creates shared library with debug symbols and no optimizations
    build_shared_lib_dbg)
        C_ARGS="-O0 -g3 -fpic -shared"
        CPP_ARGS="$C_ARGS"
        LINKER_ARGS="$CPP_ARGS $LINKER_LIBS -Wl,-soname,$SHARED_LIB_FILE"
        PRE_TASK_SCRIPT=""
        TASK_SCRIPT="@cbuild/default_tasks/build_shared_lib.sh"
        POST_TASK_SCRIPT=""
        ;;
    # creates static library
    build_static_lib)
        C_ARGS="-O2 -fpic -fdata-sections -ffunction-sections"
        CPP_ARGS="$C_ARGS"
        PRE_TASK_SCRIPT=""
        TASK_SCRIPT="@cbuild/default_tasks/build_static_lib.sh"
        POST_TASK_SCRIPT=""
        ;;
    # creates static library with debug symbols and no optimizations
    build_static_lib_dbg)
        C_ARGS="-O0 -g3"
        CPP_ARGS="$C_ARGS"
        PRE_TASK_SCRIPT=""
        TASK_SCRIPT="@cbuild/default_tasks/build_static_lib.sh"
        POST_TASK_SCRIPT=""
        ;;
    # executes $EXEC_FILE
    exec)
        TASK_SCRIPT="@cbuild/default_tasks/exec.sh"
        ;;
    # executes $EXEC_FILE with valgrind memory checker
    valgrind)  
        VALGRIND_ARGS="-s --read-var-info=yes --track-origins=yes --fullpath-after=$(pwd)/ --leak-check=full --show-leak-kinds=all" 
        TASK_SCRIPT="@cbuild/default_tasks/valgrind.sh"
        ;;
    # generates profiling info
    profile)
        OUTDIR="$OUTDIR/profile"
        # -flto applies more optimizations across object files
        # -flto=auto is needed to multithreaded copilation
        # -fuse-linker-plugin is required to use static libs with lto
        # -pg adds code to executable, that generates file containing function call info (gmon.out)
        # -fprofile-generate generates executable with profiling code
        # -fprofile-prefix-path sets path where profiling info about objects will be saved
        C_ARGS="-O2 -flto=auto -fuse-linker-plugin 
            -fprofile-generate -fprofile-prefix-path=$(realpath $OBJDIR)/objects"
        CPP_ARGS="$C_ARGS"
        LINKER_ARGS="$CPP_ARGS $LINKER_LIBS"
        PRE_TASK_SCRIPT="@cbuild/default_tasks/build_exec.sh"
        TASK_SCRIPT="@cbuild/default_tasks/profile.sh"
        POST_TASK_SCRIPT=""
        ;;
    # compiles program with -pg and runs it with gprof
    # uses gprof2dot python script to generate function call tree (pip install gprof2dot)
    # requires graphviz (https://www.graphviz.org/download/source/)
    gprof)
        OUTDIR="$OUTDIR/gprof"
        # arguments that emit some call counter code and disable optimizations to see function names
        # https://github.com/msys2/MINGW-packages/issues/8503#issuecomment-1365475205
        C_ARGS="-O0 -g -pg -no-pie -fno-omit-frame-pointer
            -fno-inline-functions -fno-inline-functions-called-once 
            -fno-optimize-sibling-calls -fopenmp"
        CPP_ARGS="$C_ARGS"
        LINKER_ARGS="$CPP_ARGS $LINKER_LIBS"
        PRE_TASK_SCRIPT="@cbuild/default_tasks/build_exec.sh"
        TASK_SCRIPT="@cbuild/default_tasks/gprof.sh"
        POST_TASK_SCRIPT=""
        ;;
    # compiles program and runs it with callgrind (part of valgrind)
    # uses gprof2dot python script to generate function call tree (pip install gprof2dot)
    # requires graphviz (https://www.graphviz.org/download/source/)
    # P.S. detailed results can be viewed in KCacheGrind
    callgrind)
        OUTDIR="$OUTDIR/callgrind"
        # -pg adds code to executable, that generates file containing function call info (gmon.out)
        C_ARGS="-O2 -flto=auto -fuse-linker-plugin"
        CPP_ARGS="$C_ARGS"
        LINKER_ARGS="$CPP_ARGS $LINKER_LIBS"
        PRE_TASK_SCRIPT="@cbuild/default_tasks/build_exec.sh"
        TASK_SCRIPT="@cbuild/default_tasks/callgrind.sh"
        POST_TASK_SCRIPT=""
        ;;
    # compiles executable with sanitizers and executes it to find errors and warnings
    sanitize)
        OUTDIR="$OUTDIR/sanitize"
        C_ARGS="-O0 -g3 -fsanitize=undefined,address"
        CPP_ARGS="$C_ARGS"
        LINKER_ARGS="$CPP_ARGS $LINKER_LIBS"
        PRE_TASK_SCRIPT="@cbuild/default_tasks/build_exec.sh"
        TASK_SCRIPT="@cbuild/default_tasks/exec.sh"
        POST_TASK_SCRIPT=""
        ;;
    # rebuilds specified dependencies
    # EXAMPLE: `cbuild rebuild_dependencies=libexample1,fonts`
    # 'all' can be specified to rebuild all dependencies
    rebuild_dependencies)
        TASK_SCRIPT="@cbuild/default_tasks/rebuild_dependencies.sh"
        ;;
    # deletes generated files
    clean)
        TASK_SCRIPT="@cbuild/default_tasks/clean.sh"
        ;;
    # nothing to do
    "" | no_task)
        ;;
    # unknown task
    *)
        error "task <$PROJECT/$TASK> not found"
    ;;
esac