cmake_minimum_required(VERSION 3.16.3)

# Set the project name and version
project(Lunarium VERSION 0.1.0)

# specify the C++ standard
set(CMAKE_CXX_STANDARD 11)
set(CMAKE_CXX_STANDARD_REQUIRED True)

configure_file(LunariumConfig.h.in LunariumConfig.h)

# Source Files
set(LUNARIUM_SRC
"src/test_main.cpp"
"src/core/core.cpp"
"src/core/state.cpp"
"src/core/Version.cpp"
"src/utils/Logger.cpp"
"src/utils/HighResTimer.cpp"
"src/utils/helpers.cpp"
"src/utils/OpRes.cpp"
)

# add the executable
add_executable(${PROJECT_NAME} ${LUNARIUM_SRC})

#       DOWNLOAD ALL SUBMODULES
find_package(Git QUIET)
if(GIT_FOUND AND EXISTS "${PROJECT_SOURCE_DIR}/.git")
# Update submodules as needed
    option(GIT_SUBMODULE "Check submodules during build" ON)
    if(GIT_SUBMODULE)
        message(STATUS "Submodule update")
        execute_process(COMMAND ${GIT_EXECUTABLE} submodule update --init --recursive
                        WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
                        RESULT_VARIABLE GIT_SUBMOD_RESULT)
        if(NOT GIT_SUBMOD_RESULT EQUAL "0")
            message(FATAL_ERROR "git submodule update --init failed with ${GIT_SUBMOD_RESULT}, please checkout submodules")
        endif()
    endif()
endif()

#       CHECK THAT ALL SUBMODULES EXIST
if(NOT EXISTS "${PROJECT_SOURCE_DIR}/external/glfw/CMakeLists.txt")
    message(FATAL_ERROR "The submodules were not downloaded! GIT_SUBMODULE was turned off or failed. Please update submodules and try again.")
endif()

if(NOT EXISTS "${PROJECT_SOURCE_DIR}/external/glm/CMakeLists.txt")
    message(FATAL_ERROR "The submodules were not downloaded! GIT_SUBMODULE was turned off or failed. Please update submodules and try again.")
endif()

if(NOT EXISTS "${PROJECT_SOURCE_DIR}/external/lua/CMakeLists.txt")
    message(FATAL_ERROR "The submodules were not downloaded! GIT_SUBMODULE was turned off or failed. Please update submodules and try again.")
endif()

if(NOT EXISTS "${PROJECT_SOURCE_DIR}/external/pugixml/CMakeLists.txt")
    message(FATAL_ERROR "The submodules were not downloaded! GIT_SUBMODULE was turned off or failed. Please update submodules and try again.")
endif()

# add GLFW
add_subdirectory(external/glfw)

# add glad2
add_subdirectory(external/glad/src)

# add GLM
add_subdirectory(external/glm)

# add dearimgui
add_subdirectory(src/dearimgui)

# add lua -- https://github.com/walterschell/Lua
add_subdirectory(external/lua)

# add pugixml
add_subdirectory(external/pugixml)

target_include_directories(${PROJECT_NAME} 
    PUBLIC "${PROJECT_BINARY_DIR}" 
    PUBLIC src
    PUBLIC external/glfw/include
    PUBLIC external/glm
    PUBLIC external/lua/lua5.4.3/include
    PUBLIC src/dearimgui
    PUBLIC external/pugixml/src
    PUBLIC external/glad/include
)

target_link_directories(${PROJECT_NAME}
    PRIVATE external/glfw/src
    PRIVATE external/glm
    PRIVATE src/dearimgui
    PRIVATE external/glad/src
)

if(WIN32)
    target_link_libraries(${PROJECT_NAME} opengl32.lib glfw glad glm dearimgui lua_static pugixml)
elseif(UNIX)
    target_link_libraries(${PROJECT_NAME} GL glfw glad glm dearimgui lua_static pugixml)
endif()