#!/usr/bin/env bash
CBUILD_VERSION=2.3.2

PROJECT="tim"
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=''

# 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"

# example: "-I./include -I$DEPENDENCIES_DIR/libexample"
INCLUDE="-Iinclude -Isrc"

# OS-specific options
case "$OS" in
    WINDOWS)
        EXEC_FILE="snek.exe"
        SHARED_LIB_FILE="$PROJECT.dll"
        INCLUDE="$INCLUDE "
        # example: "-lSDL2 -lSDL2_image"
        LINKER_LIBS=""
        ;;
    LINUX)
        EXEC_FILE="snek"
        SHARED_LIB_FILE="$PROJECT.so"
        INCLUDE="$INCLUDE "
        LINKER_LIBS=""
        ;;
    *)
        error "operating system $OS has no configuration variants"
        ;;
esac

# TASKS
case "$TASK" in
    # creates executable using profiling info if it exists
    build_exec)
        SRC_C="$SRC_C example/snek.c"
        # -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 $LINKER_LIBS"
        PRE_TASK_SCRIPT=""
        TASK_SCRIPT="@cbuild/default_tasks/build_exec.sh"
        POST_TASK_SCRIPT="@cbuild/default_tasks/strip_exec.sh"
        ;;
    # creates executable with debug info and no optimizations
    build_exec_dbg)
        SRC_C="$SRC_C example/snek.c"
        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=""
        ;;
    # 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