cmake_minimum_required(VERSION 3.16)
include(CheckIPOSupported)

project(CreatureLib)

# Enable all warnings, and make them error when occurring.
add_compile_options(-Wall -Wextra -Werror)
# We like new stuff, so set the c++ standard to c++20.
set(CMAKE_CXX_STANDARD 20)

option(WINDOWS "Whether the build target is Windows or not." OFF)
option(SHARED "Whether we should build a shared library, instead of a static one." OFF)
option(TESTS "Whether the test executable should be build as well." OFF)
option(STATICC "Whether gcc and stdc++ should be linked statically to the library." OFF)
set(LEVEL_SIZE "8" CACHE STRING "Number of bits to store the level as. Currently reserved, and can only be 8")

if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
    add_compile_options(-fconcepts)
endif ()

if (CMAKE_BUILD_TYPE MATCHES Release AND NOT WINDOWS)
    # Include debug symbols in all linux builds
    message("Including debug symbols")
    add_compile_options(-g -gline-tables-only)
endif ()

include(CmakeConanSetup.cmake)
SetupConan()

set(THREADS_PREFER_PTHREAD_FLAG ON)
find_package(Threads REQUIRED)

# Set whether we want a static or shared library.
set(LIBTYPE STATIC)
if (SHARED)
    set(LIBTYPE SHARED)
endif (SHARED)

if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
    add_link_options(-fuse-ld=lld)
endif ()

if (LEVEL_SIZE STREQUAL "8")
    add_definitions(-DLEVEL_U8)
    message(STATUS "Using level size of 8")
elseif (LEVEL_SIZE STREQUAL "16")
    add_definitions(-DLEVEL_U16)
    message(STATUS "Using level size of 16")
elseif (LEVEL_SIZE STREQUAL "32")
    add_definitions(-DLEVEL_U32)
    message(STATUS "Using level size of 32")
elseif (LEVEL_SIZE STREQUAL "64")
    add_definitions(-DLEVEL_U64)
    message(STATUS "Using level size of 64")
else ()
    message(FATAL_ERROR, "Invalid level size was given.")
endif ()

file(GLOB_RECURSE LIBRARY_SRC_FILES
        "src/*.cpp" "src/*.hpp" "CInterface/*.cpp" "CInterface/*.hpp")
add_library(CreatureLib SHARED ${LIBRARY_SRC_FILES})
target_precompile_headers(CreatureLib PUBLIC src/Precompiled.hxx)

# If interprocedural optimization is available, apply it
check_ipo_supported(RESULT IPO_SUPPORTED)
if (IPO_SUPPORTED)
    message(STATUS "IPO / LTO enabled")
    set_property(TARGET CreatureLib PROPERTY INTERPROCEDURAL_OPTIMIZATION TRUE)
endif ()

# If we are building for Windows we need to set some specific variables.
if (WINDOWS)
    MESSAGE(WARNING, "Using Windows Build.")
    # Add a definition for the compiler, so we can use it in C++ as well.
    ADD_DEFINITIONS(-D WINDOWS=1)
    # -m64: Build a 64 bit library
    add_compile_options(-m64)
    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wl,-allow-multiple-definition")
endif (WINDOWS)

# Set up links to all relevant libraries.
SET(_LIBRARYLINKS Arbutils)
if (NOT WINDOWS)
    set(_LIBRARYLINKS ${_LIBRARYLINKS} -ldw)
endif ()

# If we need to link the C libraries statically, do so.
if (STATICC)
    message(STATUS "Linking C statically.")
    SET(_LIBRARYLINKS ${_LIBRARYLINKS} -static-libgcc -static-libstdc++ -Wl,-Bstatic -lstdc++ -lpthread)
endif ()

# And link the libraries together
target_link_libraries(CreatureLib PUBLIC ${_LIBRARYLINKS} Threads::Threads)

if (TESTS)
    # Create Test executable
    file(GLOB_RECURSE TEST_FILES "tests/*.cpp" "tests/*.hpp")
    add_executable(CreatureLibTests ${TEST_FILES} extern/doctest.hpp)
    target_link_libraries(CreatureLibTests PUBLIC CreatureLib Arbutils)

    # Add a definition for the test library
    target_compile_definitions(CreatureLibTests PRIVATE TESTS_BUILD)
endif ()