"""Module for generating and reading config"""

import json
import aiofiles
import os
import traceback

from mab import MatrixBotConfig

DEFAULT_CONFIG = {
    "matrix_homeserver_url": "https://matrix.domain.net",
    "matrix_username_localpart": "short_username",
    "storage_directory": "session_storage"
}



#
# PRIVATE
#
async def write_default_config(path: str) -> None:
    try:
        async with aiofiles.open(path, "w") as f:
            await f.write(json.dumps(DEFAULT_CONFIG, indent=4))
    except:
        traceback.print_exc()



#
# PUBLIC
#
async def load_config(path: str = "config.json") -> MatrixBotConfig | None:
    """Load config from specified path. Creates default config if it does not exist (but still returns None)."""
    # no file
    if not os.path.isfile(path):
        await write_default_config(path)
        return None
    # open and read
    try:
        async with aiofiles.open(path, "r") as f:
            j = json.loads((await f.read()).strip())
    except:
        traceback.print_exc()
        return None
    # parse
    try:
        cfg = MatrixBotConfig(**j)
        return cfg
    except:
        traceback.print_exc()
        return None