cmake_minimum_required(VERSION 3.20)
project(PrismEngine)

list(APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_LIST_DIR}/cmake)

# enable folders in IDEs that support this feature
set_property(GLOBAL PROPERTY USE_FOLDERS ON)

include(${CMAKE_CURRENT_LIST_DIR}/cmake/Common.cmake)
include(${CMAKE_CURRENT_LIST_DIR}/cmake/AddPlatformExecutable.cmake)
include(FetchContent)

# options
option(BUILD_TOOLS "Build tools for curating content for Prism" OFF)
option(BUILD_EXAMPLE "Build example program" ON)

if(${CMAKE_SYSTEM_NAME} STREQUAL "Linux")
    message("Linux build detected!")

    find_package(SDL2 CONFIG)
    if(NOT TARGET SDL2::SDL2)
        find_package(SDL2 REQUIRED)
    endif()

    set(ENABLE_VULKAN TRUE)
    set(ENABLE_LINUX TRUE)

    set(NEEDS_HOSTED_SHADER_COMPILER FALSE)
endif()

if(${CMAKE_SYSTEM_NAME} STREQUAL "Darwin" AND NOT IOS)
    message("macOS build detected!")

    find_package(SDL2 REQUIRED)

    set(ENABLE_VULKAN TRUE)
    set(ENABLE_DARWIN TRUE)
    set(ENABLE_MACOS TRUE)
    set(ENABLE_METAL TRUE)

    set(CMAKE_XCODE_GENERATE_SCHEME OFF)
    set(NEEDS_HOSTED_SHADER_COMPILER FALSE)
endif()

if(${CMAKE_SYSTEM_NAME} STREQUAL "iOS")
    message("iOS build detected!")

    set(ENABLE_VULKAN TRUE)
    set(ENABLE_DARWIN TRUE)
    set(ENABLE_IOS TRUE)
    set(ENABLE_METAL TRUE)

    set(NEEDS_HOSTED_SHADER_COMPILER TRUE)
    set(EXTRA_PLATFORM_ARG "mobile")
endif()

if(${CMAKE_SYSTEM_NAME} STREQUAL "tvOS")
    message("tvOS build detected!")

    set(ENABLE_VULKAN TRUE)
    set(ENABLE_DARWIN TRUE)
    set(ENABLE_TVOS TRUE)
    set(ENABLE_METAL TRUE)

    set(NEEDS_HOSTED_SHADER_COMPILER TRUE)
    set(EXTRA_PLATFORM_ARG "mobile")
endif()

if(${CMAKE_SYSTEM_NAME} STREQUAL "Windows")
    message("Windows build detected!")

    find_package(SDL2 REQUIRED)

    set(ENABLE_WINDOWS TRUE)
    set(ENABLE_VULKAN TRUE)
    set(ENABLE_DX12 TRUE)

    set(NEEDS_HOSTED_SHADER_COMPILER FALSE)
endif()

if(${CMAKE_SYSTEM_NAME} STREQUAL "Emscripten")
    message("Web build detected!")

    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g3 -O0")

    set(ENABLE_WEB TRUE)
    set(ENABLE_WEBGPU TRUE)

    set(NEEDS_HOSTED_SHADER_COMPILER TRUE)
endif()

if(ENABLE_VULKAN)
    find_package(Vulkan REQUIRED)
    list(APPEND SHADER_LANGUAGES "spv")
endif()

if(ENABLE_DX12)
    list(APPEND SHADER_LANGUAGES "hlsl")
endif()

if(ENABLE_WEBGPU)
    list(APPEND SHADER_LANGUAGES "wgsl")
endif()

if(ENABLE_METAL)
    list(APPEND SHADER_LANGUAGES "msl")
endif()

if(NEEDS_HOSTED_SHADER_COMPILER AND (NOT DEFINED SHADER_COMPILER_LOCATION))
    message(FATAL_ERROR "You are building for a platform that needs a hosted shader compiler. Please specify the path in SHADER_COMPILER_LOCATION!")
endif()

add_subdirectory(extern)

# enable lto
if (CMAKE_BUILD_TYPE EQUAL "Release")
    set(CMAKE_INTERPROCEDURAL_OPTIMIZATION TRUE)
endif()

add_subdirectory(platforms)

set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)

add_subdirectory(engine)
add_subdirectory(tools)

if(BUILD_EXAMPLE)
    add_subdirectory(example)
endif()