import { Notification, NotificationCount } from '@/lib/types/notification';
import { NotificationAdapter } from './notification-adapter.interface';
import { prisma } from '@/lib/prisma';

// Leantime notification type from their API
interface LeantimeNotification {
  id: number;
  userId: number;
  username: string;
  message: string;
  type: string;
  moduleId: number;
  url: string;
  read: number; // 0 for unread, 1 for read
  date: string; // ISO format date
}

export class LeantimeAdapter implements NotificationAdapter {
  readonly sourceName = 'leantime';
  private apiUrl: string;
  private apiKey: string;

  constructor() {
    // Load from environment or database config
    this.apiUrl = process.env.LEANTIME_API_URL || '';
    this.apiKey = process.env.LEANTIME_API_KEY || '';
  }

  private async getLeantimeCredentials(userId: string): Promise<{ url: string, apiKey: string } | null> {
    // Get Leantime credentials from the database for this user
    const credentials = await prisma.userServiceCredentials.findFirst({
      where: {
        userId: userId,
        service: 'leantime'
      }
    });

    if (!credentials) {
      return null;
    }

    return {
      url: credentials.serviceUrl || this.apiUrl,
      apiKey: credentials.accessToken || this.apiKey,
    };
  }

  async getNotifications(userId: string, page = 1, limit = 20): Promise<Notification[]> {
    const credentials = await this.getLeantimeCredentials(userId);
    if (!credentials) {
      return [];
    }

    try {
      // Calculate offset for pagination
      const offset = (page - 1) * limit;
      
      // Make request to Leantime API
      const response = await fetch(
        `${credentials.url}/api/notifications?limit=${limit}&offset=${offset}`,
        {
          headers: {
            'Authorization': `Bearer ${credentials.apiKey}`,
            'Content-Type': 'application/json'
          }
        }
      );

      if (!response.ok) {
        console.error(`Failed to fetch Leantime notifications: ${response.status}`);
        return [];
      }

      const data = await response.json();
      return this.transformNotifications(data, userId);
    } catch (error) {
      console.error('Error fetching Leantime notifications:', error);
      return [];
    }
  }

  async getNotificationCount(userId: string): Promise<NotificationCount> {
    const credentials = await this.getLeantimeCredentials(userId);
    if (!credentials) {
      return {
        total: 0,
        unread: 0,
        sources: {
          leantime: {
            total: 0,
            unread: 0
          }
        }
      };
    }

    try {
      // Make request to Leantime API
      const response = await fetch(
        `${credentials.url}/api/notifications/count`,
        {
          headers: {
            'Authorization': `Bearer ${credentials.apiKey}`,
            'Content-Type': 'application/json'
          }
        }
      );

      if (!response.ok) {
        console.error(`Failed to fetch Leantime notification count: ${response.status}`);
        return {
          total: 0,
          unread: 0,
          sources: {
            leantime: {
              total: 0,
              unread: 0
            }
          }
        };
      }

      const data = await response.json();
      const unreadCount = data.unread || 0;
      const totalCount = data.total || 0;

      return {
        total: totalCount,
        unread: unreadCount,
        sources: {
          leantime: {
            total: totalCount,
            unread: unreadCount
          }
        }
      };
    } catch (error) {
      console.error('Error fetching Leantime notification count:', error);
      return {
        total: 0,
        unread: 0,
        sources: {
          leantime: {
            total: 0,
            unread: 0
          }
        }
      };
    }
  }

  async markAsRead(userId: string, notificationId: string): Promise<boolean> {
    const credentials = await this.getLeantimeCredentials(userId);
    if (!credentials) {
      return false;
    }

    try {
      // Extract the source ID from our compound ID
      const sourceId = notificationId.replace(`${this.sourceName}-`, '');
      
      // Make request to Leantime API
      const response = await fetch(
        `${credentials.url}/api/notifications/${sourceId}/read`,
        {
          method: 'POST',
          headers: {
            'Authorization': `Bearer ${credentials.apiKey}`,
            'Content-Type': 'application/json'
          }
        }
      );

      return response.ok;
    } catch (error) {
      console.error('Error marking Leantime notification as read:', error);
      return false;
    }
  }

  async markAllAsRead(userId: string): Promise<boolean> {
    const credentials = await this.getLeantimeCredentials(userId);
    if (!credentials) {
      return false;
    }

    try {
      // Make request to Leantime API
      const response = await fetch(
        `${credentials.url}/api/notifications/read-all`,
        {
          method: 'POST',
          headers: {
            'Authorization': `Bearer ${credentials.apiKey}`,
            'Content-Type': 'application/json'
          }
        }
      );

      return response.ok;
    } catch (error) {
      console.error('Error marking all Leantime notifications as read:', error);
      return false;
    }
  }

  async isConfigured(): Promise<boolean> {
    return !!(this.apiUrl && this.apiKey);
  }

  private transformNotifications(data: LeantimeNotification[], userId: string): Notification[] {
    if (!Array.isArray(data)) {
      return [];
    }

    return data.map(notification => ({
      id: `${this.sourceName}-${notification.id}`,
      source: this.sourceName as 'leantime',
      sourceId: notification.id.toString(),
      type: notification.type,
      title: notification.type, // Leantime doesn't provide a separate title
      message: notification.message,
      link: notification.url,
      isRead: notification.read === 1,
      timestamp: new Date(notification.date),
      priority: 'normal', // Default priority as Leantime doesn't specify
      user: {
        id: userId,
        name: notification.username
      },
      metadata: {
        moduleId: notification.moduleId
      }
    }));
  }
}