import json
import os
from pathlib import Path
from typing import Optional

import aiofiles

CONFIG_PATH = Path(os.getenv("CONFIG_PATH", "/app/data/config.json"))


async def load_config() -> dict:
    if CONFIG_PATH.is_dir():
        return {}
    if not CONFIG_PATH.exists():
        return {}
    async with aiofiles.open(CONFIG_PATH, "r") as f:
        data = await f.read()
        return json.loads(data)


async def save_config(config: dict) -> None:
    CONFIG_PATH.parent.mkdir(parents=True, exist_ok=True)
    async with aiofiles.open(CONFIG_PATH, "w") as f:
        await f.write(json.dumps(config, indent=2))


async def _get_guild_config(guild_id: int) -> dict:
    config = await load_config()
    return config.get(str(guild_id), {})


async def get_output_channel(guild_id: int) -> Optional[int]:
    guild_config = await _get_guild_config(guild_id)
    return guild_config.get("output_channel_id")


async def set_output_channel(guild_id: int, channel_id: int) -> None:
    config = await load_config()
    guild_key = str(guild_id)
    guild_config = config.get(guild_key, {})
    guild_config["output_channel_id"] = channel_id
    config[guild_key] = guild_config
    await save_config(config)


async def get_retry_state(guild_id: int) -> Optional[dict]:
    guild_config = await _get_guild_config(guild_id)
    retry_state = guild_config.get("retry_state")
    return retry_state if isinstance(retry_state, dict) else None


async def set_retry_state(guild_id: int, file_path: str, source_channel_id: int | None, reason: str) -> None:
    config = await load_config()
    guild_key = str(guild_id)
    guild_config = config.get(guild_key, {})
    guild_config["retry_state"] = {
        "file_path": file_path,
        "source_channel_id": source_channel_id,
        "reason": reason,
    }
    config[guild_key] = guild_config
    await save_config(config)


async def clear_retry_state(guild_id: int) -> None:
    config = await load_config()
    guild_key = str(guild_id)
    guild_config = config.get(guild_key)
    if not guild_config:
        return
    guild_config.pop("retry_state", None)
    config[guild_key] = guild_config
    await save_config(config)