from typing import Callable, Optional

from server.db.models import Settings


def set_single_settings(data: list):
    """Set single settings item.

    Args:
        data: List of accounts.

    """
    for item in data:
        if item.settings:
            item.settings_item = item.settings[0]


async def migrate_settings_v1_to_v2(account_id: int, subtype: str):
    """Migrates settings from version 1 to version 2
    Description:
        Example settings version 1:
            {"markets": ["global"], "vendors": {"apple": true, "spotify": false}, "notifications": true}
        Example settings version 2:
            {
              "markets": [
                "global"
              ],
              "categories": {
                "charts": {
                  "apple_top_100": true,
                  "spotify_top_200": false
                },
                "starred_tracks": {
                  "apple": true,
                  "spotify": false
                },
                "starred_playlists": {
                  "apple": true,
                  "spotify": false
                }
              },
              "notifications": true
            }
    """
    setting = await Settings.get(account_id=account_id, type=subtype, version=1)
    if not setting:
        return None
    data = setting.data
    categories = {
        "charts": {"apple": False, "spotify": False},
        "starred_tracks": {"apple": False, "spotify": False},
        "starred_playlists": {"apple": False, "spotify": False},
    }
    vendors = data.pop("vendors", {})
    for vendor, value in vendors.items():
        if vendor == "apple" and value is True:
            categories["starred_tracks"]["apple"] = True
            categories["starred_playlists"]["apple"] = True
            categories["charts"]["apple"] = True
        if vendor == "spotify" and value is True:
            categories["starred_tracks"]["spotify"] = True
            categories["starred_playlists"]["spotify"] = True
            categories["charts"]["spotify"] = True
    data["categories"] = categories
    return await Settings.update({"data": data, "version": 2}, id=setting.id, return_source=Settings)


USER_SETTING_HANDLER = {2: migrate_settings_v1_to_v2}


def settings_migration_handler(version: int) -> Optional[Callable[[], None]]:
    """Get handler to migrate previous user settings if possible
    Args:
        version: str - version of user settings
    Returns:
        Handler for a current version or None
    """
    return USER_SETTING_HANDLER.get(version)