cmake_minimum_required( VERSION 3.1.0 )

project( date_prj )

include( GNUInstallDirs )

find_package( Threads REQUIRED )

# Override by setting on CMake command line.
set( CMAKE_CXX_STANDARD 17 CACHE STRING "The C++ standard whose features are requested.")

option( USE_SYSTEM_TZ_DB "Use the operating system's timezone database" OFF )
option( USE_TZ_DB_IN_DOT "Save the timezone database in the current folder" OFF )
option( BUILD_SHARED_LIBS  "Build a shared version of library" OFF )
option( ENABLE_DATE_TESTING "Enable unit tests" ON )
option( DISABLE_STRING_VIEW "Disable string view" OFF )

function( print_option OPT )
	if ( NOT DEFINED PRINT_OPTION_CURR_${OPT} OR ( NOT PRINT_OPTION_CURR_${OPT} STREQUAL ${OPT} ) )
		set( PRINT_OPTION_CURR_${OPT} ${${OPT}} CACHE BOOL "" )
		mark_as_advanced(PRINT_OPTION_CURR_${OPT})
		message( "# date: ${OPT} ${${OPT}}" )
	endif( )
endfunction( )

print_option( USE_SYSTEM_TZ_DB )
print_option( USE_TZ_DB_IN_DOT )
print_option( BUILD_SHARED_LIBS  )
print_option( ENABLE_DATE_TESTING )
print_option( DISABLE_STRING_VIEW )

set( HEADER_FOLDER "include" )
set( SOURCE_FOLDER "src" )
set( TEST_FOLDER "test" )

# This is needed so IDE's live MSVC show header files
set( HEADER_FILES
	${HEADER_FOLDER}/date/chrono_io.h
	${HEADER_FOLDER}/date/date.h
	${HEADER_FOLDER}/date/ios.h
	${HEADER_FOLDER}/date/islamic.h
	${HEADER_FOLDER}/date/iso_week.h
	${HEADER_FOLDER}/date/julian.h
	${HEADER_FOLDER}/date/tz.h
	${HEADER_FOLDER}/date/tz_private.h
)

add_library( tz ${HEADER_FILES} ${SOURCE_FOLDER}/tz.cpp )

if( USE_SYSTEM_TZ_DB )
	target_compile_definitions( tz PRIVATE -DUSE_AUTOLOAD=0 )
	target_compile_definitions( tz PRIVATE -DHAS_REMOTE_API=0 )
	# cannot set USE_OS_TZDB to 1 on Windows
	if( NOT WIN32 )
		target_compile_definitions( tz PUBLIC -DUSE_OS_TZDB=1 )
	endif( )
else( )
	target_compile_definitions( tz PRIVATE -DUSE_AUTOLOAD=1 )
	target_compile_definitions( tz PRIVATE -DHAS_REMOTE_API=1 )
	target_compile_definitions( tz PUBLIC -DUSE_OS_TZDB=0 )
	find_package( CURL REQUIRED )
	include_directories( SYSTEM ${CURL_INCLUDE_DIRS} )
	set( OPTIONAL_LIBRARIES ${CURL_LIBRARIES} )
endif( )

if( USE_TZ_DB_IN_DOT )
	target_compile_definitions( tz PRIVATE -DINSTALL=. )
endif( )

if( DISABLE_STRING_VIEW )
    target_compile_definitions( tz PRIVATE -DHAS_STRING_VIEW=0 )
endif( )

if( BUILD_SHARED_LIBS )
    set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -fPIC")
    set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -fPIC")
endif( )

target_link_libraries( tz ${CMAKE_THREAD_LIBS_INIT} ${OPTIONAL_LIBRARIES} )

# add include folders to the library and targets that consume it
target_include_directories(tz PUBLIC
    $<BUILD_INTERFACE:
        ${CMAKE_CURRENT_SOURCE_DIR}/${HEADER_FOLDER}
    >
    $<INSTALL_INTERFACE:
        include
    >
)

add_library(date_interface INTERFACE) # an interface (not a library), to enable automatic include_directory (for when just date.h, but not "tz.h and its lib" are needed)

# add include folders to the INTERFACE and targets that consume it
target_include_directories(date_interface INTERFACE
    "$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>"
    $<INSTALL_INTERFACE:include>
)

if(WIN32 AND NOT CYGWIN)
    set(DEF_INSTALL_CMAKE_DIR CMake)
else()
    set(DEF_INSTALL_CMAKE_DIR ${CMAKE_INSTALL_LIBDIR}/cmake/date)
endif()

install( TARGETS date_interface EXPORT dateConfig )
install( EXPORT dateConfig DESTINATION ${DEF_INSTALL_CMAKE_DIR} )
install( TARGETS tz
	ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
	LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
	RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})  # This is for Windows
install( DIRECTORY ${HEADER_FOLDER}/ DESTINATION include/ )

if ( ENABLE_DATE_TESTING )

    enable_testing( )

    add_custom_target( testit COMMAND ${CMAKE_CTEST_COMMAND} )

    add_dependencies( testit tz )
    function( add_pass_tests TEST_GLOB TEST_PREFIX )
        file( GLOB_RECURSE FILENAMES ${TEST_GLOB} )
        include_directories( "${HEADER_FOLDER}/date" )

        foreach( TEST_FILE ${FILENAMES} )
            get_filename_component( TEST_NAME ${TEST_FILE} NAME_WE )
            get_filename_component( TEST_EXT ${TEST_FILE} EXT )
            if( NOT ${TEST_EXT} STREQUAL ".fail.cpp" )
                set( PREFIX "${TEST_PREFIX}_pass_${TEST_NAME}" )
                set( BIN_NAME ${PREFIX}_bin )
                set( TST_NAME ${PREFIX}_test )
                add_executable( ${BIN_NAME} EXCLUDE_FROM_ALL ${TEST_FILE} )
                add_test( ${TST_NAME} ${BIN_NAME} )
                target_link_libraries( ${BIN_NAME} tz )
                add_dependencies( testit ${BIN_NAME} )
            endif( )
        endforeach( )
    endfunction( )

    function( add_fail_tests TEST_GLOB TEST_PREFIX )
        file( GLOB_RECURSE FILENAMES ${TEST_GLOB} )

        foreach( TEST_FILE ${FILENAMES} )
            get_filename_component( TEST_NAME ${TEST_FILE} NAME_WE )
            get_filename_component( TEST_EXT ${TEST_FILE} EXT )

                set( TEST_TYPE "_fail" )

            set( PREFIX "${TEST_PREFIX}_fail_${TEST_NAME}" )
            set( BIN_NAME ${PREFIX}_bin )
            set( TST_NAME ${PREFIX}_test )

            #target_compile_definitions( ${BIN_NAME} PRIVATE ${TST_NAME} )
            set( TEST_BIN_NAME ${CMAKE_BINARY_DIR}/${BIN_NAME} )
            add_custom_target( ${BIN_NAME}
                COMMAND ${PROJECT_SOURCE_DIR}/compile_fail.sh ${TEST_BIN_NAME} ${CMAKE_CXX_COMPILER} -std=c++14 -L${CMAKE_BINARY_DIR}/ -ltz -I${PROJECT_SOURCE_DIR}/${HEADER_FOLDER}/date -o ${BIN_NAME} ${TEST_FILE}
                WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
                COMMENT ${TST_NAME}
                )
            add_test( ${TST_NAME} "${PROJECT_SOURCE_DIR}/test_fail.sh" ${CMAKE_BINARY_DIR}/${BIN_NAME} WORKING_DIRECTORY "${PROJECT_SOURCE_DIR}/" )
            #set_tests_properties( ${TST_NAME} PROPERTIES WILL_FAIL TRUE)
            add_dependencies( testit ${BIN_NAME} )
        endforeach( )
    endfunction( )

    file( GLOB children RELATIVE "${PROJECT_SOURCE_DIR}/${TEST_FOLDER}" "${PROJECT_SOURCE_DIR}/${TEST_FOLDER}/*" )
    foreach( child ${children} )
        if( IS_DIRECTORY "${PROJECT_SOURCE_DIR}/${TEST_FOLDER}/${child}" )
            set( CUR_FOLDER "${PROJECT_SOURCE_DIR}/${TEST_FOLDER}/${child}" )
            add_pass_tests( "${CUR_FOLDER}/*.cpp" ${child} )
            if( NOT WIN32 )
                add_fail_tests( "${CUR_FOLDER}/*.fail.cpp" ${child} )
            endif( )
        endif( )
    endforeach( )
endif( )