import json
from urllib.error import HTTPError, URLError
from urllib.request import Request, urlopen

from backend.app.plugins.base import BasePlugin

DEFAULT_POST_PREFIX = 'From my #LinkLog: "'


class DefaultFrontendPlugin(BasePlugin):
    name = 'default_frontend'
    version = '1.0.0'

    def handle_event(self, event):
        return {'status': 'accepted', 'plugin': self.name, 'event': event.get('type')}


class MastodonPlugin(BasePlugin):
    name = 'mastodon'
    version = '1.0.0'
    enabled = False
    config = {}

    def initialize(self, config=None):
        self.config = config or {}
        return True

    def handle_event(self, event):
        config = dict(self.config)
        user_id = event.get('user_id')
        if user_id:
            from backend.app.database import get_connection

            with get_connection() as conn:
                row = conn.execute(
                    '''
                    SELECT config FROM user_plugin_config
                    WHERE user_id = ? AND plugin_name = ?
                    ''',
                    (user_id, self.name),
                ).fetchone()
            if row and row['config']:
                config.update(json.loads(row['config']))

        instance = str(config.get('instance', '')).strip().rstrip('/')
        if instance and '://' not in instance:
            instance = f'https://{instance}'
        access_token = str(config.get('access_token', '')).strip()
        if not instance or not access_token:
            return {'status': 'skipped', 'plugin': self.name, 'reason': 'not_configured'}

        status_parts = [event.get('title') or event.get('url', '')]
        if event.get('comment'):
            status_parts.append(event['comment'])
        post_prefix = config.get('post_prefix')
        if post_prefix is None and config.get('hashtag'):
            post_prefix = f'#{str(config["hashtag"]).strip().lstrip("#")} '
        post_prefix = str(post_prefix if post_prefix is not None else DEFAULT_POST_PREFIX)
        status_parts.append(f'{post_prefix}{event.get("url", "")}'.strip())

        try:
            request = Request(
                f'{instance}/api/v1/statuses',
                data=json.dumps({'status': '\n'.join(status_parts)}).encode('utf-8'),
                headers={
                    'Authorization': f'Bearer {access_token}',
                    'Content-Type': 'application/json',
                },
                method='POST',
            )
            with urlopen(request, timeout=5) as response:
                response_data = json.loads(response.read().decode('utf-8'))
            return {
                'status': 'posted',
                'plugin': self.name,
                'post_id': response_data.get('id'),
            }
        except (HTTPError, URLError, TimeoutError, OSError, ValueError) as error:
            return {
                'status': 'failed',
                'plugin': self.name,
                'reason': str(error),
            }


class PluginManager:
    def __init__(self):
        self.plugins = [DefaultFrontendPlugin(), MastodonPlugin()]

    def refresh_from_db(self):
        from backend.app.database import get_connection

        with get_connection() as conn:
            rows = conn.execute('SELECT name, enabled, config FROM plugins').fetchall()

        enabled_names = {row['name'] for row in rows if row['enabled']}
        for plugin in self.plugins:
            plugin.enabled = plugin.name in enabled_names
            row = next((item for item in rows if item['name'] == plugin.name), None)
            plugin.initialize(json.loads(row['config']) if row and row['config'] else {})
        return enabled_names

    def dispatch(self, event):
        self.refresh_from_db()
        results = []
        for plugin in self.plugins:
            if plugin.enabled:
                results.append(plugin.handle_event(event))
        return results


plugin_manager = PluginManager()