cmake_minimum_required(VERSION 3.24)
if(POLICY CMP0205)
    cmake_policy(SET CMP0205 NEW)
endif()
project(shweets_sim LANGUAGES C CXX)

set(CMAKE_CXX_STANDARD 20)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_EXPORT_COMPILE_COMMANDS ON)

# Two builds: Release (the default) and Debug.
if(NOT CMAKE_BUILD_TYPE STREQUAL "Debug")
    set(CMAKE_BUILD_TYPE Release)
endif()

if(MSVC)
    add_compile_options(/utf-8)
endif()

# Release builds: -O2, link-time optimization, unused code and data dropped, and the symbols stripped.
if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
    set(CMAKE_INTERPROCEDURAL_OPTIMIZATION_RELEASE ON)
    add_compile_options("$<$<CONFIG:Release>:-O2;-ffunction-sections;-fdata-sections>")
    add_link_options("$<$<CONFIG:Release>:-Wl,--gc-sections;-s>")
endif()

# SDL: static, with only the video (OpenGL) and audio pieces the game uses.
set(SDL_SHARED OFF CACHE BOOL "" FORCE)
set(SDL_STATIC ON CACHE BOOL "" FORCE)
set(SDL_OPENGL ON CACHE BOOL "" FORCE)
set(SDL_TEST_LIBRARY OFF CACHE BOOL "" FORCE)
set(SDL_EXAMPLES OFF CACHE BOOL "" FORCE)
foreach(OPTION RENDER GPU VULKAN CAMERA HAPTIC HIDAPI JOYSTICK POWER SENSOR DIALOG TRAY OPENGLES OFFSCREEN DUMMYVIDEO
        DISKAUDIO DUMMYAUDIO OSS JACK SNDIO KMSDRM IBUS LIBURING)
    set(SDL_${OPTION} OFF CACHE BOOL "" FORCE)
endforeach()
add_subdirectory(external/sdl EXCLUDE_FROM_ALL)

# simdjson: its single-file build, static, without exceptions, with only the AVX2 parser and the portable one.
add_library(simdjson STATIC external/simdjson/singleheader/simdjson.cpp)
target_include_directories(simdjson SYSTEM PUBLIC external/simdjson/singleheader)
target_compile_definitions(simdjson PUBLIC SIMDJSON_EXCEPTIONS=0 SIMDJSON_IMPLEMENTATION_ICELAKE=0
                           SIMDJSON_IMPLEMENTATION_WESTMERE=0)

# Dear ImGui: the core, and its SDL3 and OpenGL 3 backends.
add_library(imgui STATIC external/imgui/imgui.cpp external/imgui/imgui_draw.cpp external/imgui/imgui_tables.cpp
            external/imgui/imgui_widgets.cpp external/imgui/backends/imgui_impl_sdl3.cpp
            external/imgui/backends/imgui_impl_opengl3.cpp)
target_include_directories(imgui SYSTEM PUBLIC external/imgui external/imgui/backends)
target_compile_definitions(imgui PUBLIC IMGUI_DISABLE_OBSOLETE_FUNCTIONS IMGUI_DISABLE_DEMO_WINDOWS)
target_link_libraries(imgui PUBLIC SDL3::SDL3-static)

file(GLOB SOURCES CONFIGURE_DEPENDS src/*.cpp)
add_executable(shweets_sim ${SOURCES})
target_include_directories(shweets_sim SYSTEM PRIVATE external/stb)
target_link_libraries(shweets_sim PRIVATE imgui simdjson)
target_compile_definitions(shweets_sim PRIVATE "$<$<CONFIG:Debug>:DEBUG>")
set_target_properties(shweets_sim PROPERTIES OUTPUT_NAME shweets-sim)

file(CREATE_LINK ${CMAKE_SOURCE_DIR}/resources ${CMAKE_BINARY_DIR}/resources COPY_ON_ERROR SYMBOLIC)

if(WIN32)
    set_target_properties(shweets_sim PROPERTIES WIN32_EXECUTABLE ON)
    target_sources(shweets_sim PRIVATE shweets-sim.rc)
endif()

# Emscripten: WebGL2, the resources preloaded, the prefs folder kept in browser storage (web/pre.js), and a page whose
# canvas fills the window.
if(EMSCRIPTEN)
    set_target_properties(shweets_sim PROPERTIES OUTPUT_NAME index SUFFIX ".html")
    target_link_options(shweets_sim PRIVATE -sALLOW_MEMORY_GROWTH=1 -sMIN_WEBGL_VERSION=2 -sMAX_WEBGL_VERSION=2
                        -lidbfs.js "--preload-file=${CMAKE_SOURCE_DIR}/resources@/resources"
                        "--shell-file=${CMAKE_SOURCE_DIR}/web/index.html" "--pre-js=${CMAKE_SOURCE_DIR}/web/pre.js")
endif()