import binascii
from common import func_name_to_caps, write_epilogue, write_preamble, FIRST_PARAM_BLACKLIST, FUNC_BLACKLIST

HEADER_GUARD = 'VK_CAPTURE_FUNCTION_IDS_H_INCLUDED'
_dbg_hashes = set()


def write_funccase(f, cmd):
    if 'alias' in cmd or cmd["name"] in FUNC_BLACKLIST:
        return
    if len(cmd['params']) > 0 and cmd['params'][0]['type'] in FIRST_PARAM_BLACKLIST:
        return
    funchash = binascii.crc32(cmd['name'].encode('utf8'))
    f.write(f"""
    case VK_FUNCTION_{func_name_to_caps(cmd['name'])}_MWN:
        *pName = "{cmd['name']}";
        return VK_SUCCESS;""")

    # just to make sure there are no hash collisions, we wouldn't want that
    global _dbg_hashes
    assert(funchash not in _dbg_hashes)
    _dbg_hashes.add(funchash)

def generate(targets):
    assert(len(targets) == 1)
    with open(targets[0], 'w') as f:
        write_preamble(f, includes = ['<vulkan/vulkan.h>', '"vk_function_ids.h"'])
        commands = list(vulkan_hpp['commands'].values())
        commands.sort(key=lambda cmd: cmd['platform'])
        plat = ''
        f.write("""
VkResult vkGetFunctionNameMWN(VkDevice /* device */, VkFunctionMWN function, const char** pName)
{
    switch(function)
    {""")
        for cmd in commands:
            if plat != cmd['platform']:
                if plat != '':
                    f.write(f"""
#endif // defined({vulkan_hpp['platforms'][plat]['protect']})\n""")
                plat = cmd['platform']
                f.write(f"""
#if defined({vulkan_hpp['platforms'][plat]['protect']})\n""")
            write_funccase(f, cmd)
        # finish the final platform
        f.write(f"""#endif // defined({vulkan_hpp['platforms'][plat]['protect']})\n""")
        f.write("""
    default:
        return VK_ERROR_UNKNOWN;
    }
}
""")
        write_epilogue(f)