cmake_minimum_required(VERSION 3.10)

set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY)

set(TC_PREFIX riscv32-picolibc-elf-)
# Set compiler and tools
set(CMAKE_C_COMPILER "${TC_PREFIX}gcc" CACHE INTERNAL "C Compiler")
find_program(CMAKE_OBJCOPY "${TC_PREFIX}objcopy")

if (CMAKE_OBJCOPY)
  message(STATUS "Found objcopy at ${CMAKE_OBJCOPY}")
else()
  message(FATAL_ERROR "Could not find ${TC_PREFIX}objcopy.")
endif()

find_program(CMAKE_OBJDUMP "${TC_PREFIX}objdump")
if (CMAKE_OBJDUMP)
  message(STATUS "Found objdump at ${CMAKE_OBJDUMP}")
else()
  message(FATAL_ERROR "Could not find ${TC_PREFIX}objdump.")
endif()

set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
file(REAL_PATH "stubs/libgloss_stub.c" LIBGLOSS_STUB)


# Configure for Bare Metal.
set(CMAKE_SYSTEM_NAME Generic)
set(CMAKE_SYSTEM_PROCESSOR riscv32)

include(cmake/fiddle.cmake)

project (ch537 LANGUAGES C ASM)

# Set compiler and linker flags
file(GLOB LINKER_SCRIPT "linker/*.ld")
set(CMAKE_C_FLAGS "-march=rv32imac_zicsr -mabi=ilp32 -lgcc -static -O -std=gnu99" CACHE INTERNAL "C Compiler options")
set(CMAKE_ASM_FLAGS "-march=rv32imac_zicsr -mabi=ilp32 -lgcc -static -O -std=gnu99" CACHE INTERNAL "C Compiler options")
set(CMAKE_EXE_LINKER_FLAGS "-static -L ${CMAKE_BINARY_DIR}/lib -lmain -T ${LINKER_SCRIPT}" CACHE INTERNAL "Linker options")

include_directories(include linker ${CMAKE_BINARY_DIR}/generated/fdl)

file(GLOB_RECURSE SOURCES "src/*.c" "src/*.s")

message("Sources ${SOURCES}")

file(REAL_PATH "ch-flash/" CH_FLASH_DIR)

add_library(libmain STATIC ${SOURCES})
set_target_properties(libmain PROPERTIES
    ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib
    OUTPUT_NAME main
)

add_library(libgloss_stub STATIC ${LIBGLOSS_STUB})
set_target_properties(libgloss_stub PROPERTIES
    ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib
    OUTPUT_NAME gloss
)

add_dependencies(libmain fdl_headers)

set(fdl_headers)
file(GLOB_RECURSE fdl_files "${CMAKE_SOURCE_DIR}/fdl/*.fdl")
fiddle_sources(fdl_headers "${fdl_files}")
add_custom_target( fdl_headers DEPENDS ${fdl_headers})

add_custom_command(
  OUTPUT ${CMAKE_BINARY_DIR}/main.elf
  DEPENDS libmain libgloss_stub
  COMMENT "Link main.elf"
  COMMAND ${CMAKE_C_COMPILER} -nostartfiles -lgcc
          -static -L ${CMAKE_BINARY_DIR}/lib -T ${LINKER_SCRIPT}
          -o ${CMAKE_BINARY_DIR}/main.elf
          -Wl,--no-whole-archive
          -Wl,--whole-archive ${CMAKE_BINARY_DIR}/lib/libmain.a
          -Wl,--no-whole-archive
)

# Generates the binary with objcopy.
add_custom_command(
    OUTPUT main.bin
    DEPENDS ${CMAKE_BINARY_DIR}/main.elf
    COMMENT "objcopy -O binary main.elf main.bin"
    COMMAND ${CMAKE_OBJCOPY} -O binary main.elf main.bin
)

add_custom_command(
    OUTPUT objdump.txt
    DEPENDS main.elf
    COMMAND ${CMAKE_OBJDUMP} -D main.elf > objdump.txt
)

add_custom_target(main_bin ALL DEPENDS main.bin objdump.txt)

# Generates the flash binary
add_custom_command(
  OUTPUT ${CH_FLASH_DIR}/ch-flash
  COMMAND cd ${CH_FLASH_DIR} && make
)

add_custom_target(
  flash
  DEPENDS main.bin ${CH_FLASH_DIR}/ch-flash
  COMMAND ${CH_FLASH_DIR}/ch-flash -f main.bin
)

# Uncomment to add debugging support
# add_custom_target(
#   debug
#   COMMAND "${TC_PREFIX}gdb" -tui -ex "tar ext :3333" -ex "file main.elf"
# )