import { Playlist, ServerType, ApiResponse, PlexServerConnection, PlexConnectionSettings, PlexLibrary, SyncStrategy, RegexReplacement } from '../types';
import { MOCK_LOCAL_PLAYLISTS, MOCK_CLOUD_PLAYLISTS } from './mockData';

const SIMULATE_DELAY_MS = 800;

// Mock available libraries on a server
const MOCK_LIBRARIES: PlexLibrary[] = [
  { id: 'lib1', title: 'Music (Flac)', type: 'artist' },
  { id: 'lib2', title: 'MP3 Collection', type: 'artist' },
  { id: 'lib3', title: 'Soundtracks', type: 'artist' },
  { id: 'lib4', title: 'Audiobooks', type: 'artist' }
];

// Helper to simulate network request or call actual API
const fetchPlaylists = async (type: ServerType, signal?: AbortSignal): Promise<Playlist[]> => {
  return new Promise((resolve, reject) => {
    const timer = setTimeout(() => {
      if (type === ServerType.LOCAL) {
        resolve([...MOCK_LOCAL_PLAYLISTS]);
      } else {
        resolve([...MOCK_CLOUD_PLAYLISTS]);
      }
    }, SIMULATE_DELAY_MS);

    if (signal) {
      signal.addEventListener('abort', () => {
        clearTimeout(timer);
        reject(new DOMException('Aborted', 'AbortError'));
      });
    }
  });
};

const fetchServerStatus = async (signal?: AbortSignal): Promise<PlexServerConnection> => {
  return new Promise((resolve, reject) => {
    const timer = setTimeout(() => {
      // 90% chance of success for demo
      const isSuccess = Math.random() > 0.1; 
      if (isSuccess) {
        resolve({
          isConnected: true,
          name: 'Home Media Server',
          ip: '192.168.1.105',
          port: 32400,
          libraryName: 'Music (Flac)'
        });
      } else {
        resolve({
          isConnected: false
        });
      }
    }, SIMULATE_DELAY_MS);

    if (signal) {
      signal.addEventListener('abort', () => {
        clearTimeout(timer);
        reject(new DOMException('Aborted', 'AbortError'));
      });
    }
  });
};

const authenticatePlex = async (settings: PlexConnectionSettings, signal?: AbortSignal): Promise<{ token: string, serverInfo: PlexServerConnection }> => {
  return new Promise((resolve, reject) => {
    // Determine effective timeout
    const timeoutSeconds = settings.timeout || 9;
    const timeoutMs = timeoutSeconds * 1000;
    
    // Simulate latency (random between 1s and 2s, or longer to test timeout)
    const latency = 1500; 

    const timer = setTimeout(() => {
      // Check if we timed out (simulated)
      if (latency > timeoutMs) {
         reject(new Error(`Connection timed out after ${settings.timeout}s`));
         return;
      }

      // Simulate validation
      if (!settings.address) {
        reject(new Error("Server address is required"));
        return;
      }

      // If user provided username/password, mock a token generation
      let token = settings.token;
      if (!token && settings.username && settings.password) {
        token = "MOCK_TOKEN_XYZ_999";
      } else if (!token) {
         reject(new Error("Token or Username/Password required"));
         return;
      }

      // Success response with libraries
      resolve({
        token: token,
        serverInfo: {
          isConnected: true,
          name: 'My Plex Server',
          ip: settings.address,
          port: parseInt(settings.port) || 32400,
          libraryName: MOCK_LIBRARIES[0].title, // Default to first library
          libraries: MOCK_LIBRARIES
        }
      });
    }, latency);

    // Handle User Cancellation
    if (signal) {
      signal.addEventListener('abort', () => {
        clearTimeout(timer);
        reject(new DOMException('Aborted', 'AbortError'));
      });
    }
    
    // Handle Actual Timeout Logic (if latency was indeterminate in real world)
    // In this mock, the latency is fixed at 1500, but logic above simulates the check.
    // However, if the user set timeout < 1.5s, we should reject sooner.
    if (timeoutMs < latency) {
       setTimeout(() => {
          clearTimeout(timer);
          reject(new Error(`Connection timed out after ${settings.timeout}s`));
       }, timeoutMs);
    }
  });
}

const triggerSync = async (strategy: SyncStrategy, regexRules: RegexReplacement[]): Promise<void> => {
  return new Promise((resolve) => {
    // Simulate a sync process taking 3 seconds
    setTimeout(() => {
      resolve();
    }, 3000);
  });
};

export const apiService = {
  getPlaylists: async (serverType: ServerType, signal?: AbortSignal): Promise<ApiResponse<Playlist[]>> => {
    try {
      const data = await fetchPlaylists(serverType, signal);
      return { data, status: 'success' };
    } catch (error: any) {
      if (error.name === 'AbortError') {
        // Return a specific status or handle gracefully
        return { data: [], status: 'error', message: 'Request cancelled' };
      }
      console.error(`Error fetching ${serverType} playlists:`, error);
      return { data: [], status: 'error', message: 'Failed to fetch playlists' };
    }
  },

  getServerStatus: async (signal?: AbortSignal): Promise<ApiResponse<PlexServerConnection>> => {
    try {
      const data = await fetchServerStatus(signal);
      return { data, status: 'success' };
    } catch (error: any) {
      if (error.name === 'AbortError') return { data: { isConnected: false }, status: 'error', message: 'Cancelled' };
      return { 
        data: { isConnected: false }, 
        status: 'error', 
        message: 'Failed to connect to server' 
      };
    }
  },

  connectToPlex: async (settings: PlexConnectionSettings, signal?: AbortSignal): Promise<ApiResponse<{ token: string, serverInfo: PlexServerConnection }>> => {
    try {
      const data = await authenticatePlex(settings, signal);
      return { data, status: 'success', message: 'Connected successfully' };
    } catch (error: any) {
      if (error.name === 'AbortError') {
         return { 
          data: { token: '', serverInfo: { isConnected: false } }, 
          status: 'error', 
          message: 'Connection cancelled' 
        };
      }
      return { 
        data: { token: '', serverInfo: { isConnected: false } }, 
        status: 'error', 
        message: error.message || 'Connection failed' 
      };
    }
  },

  syncPlaylists: async (strategy: SyncStrategy, regexRules: RegexReplacement[]): Promise<ApiResponse<null>> => {
    try {
      await triggerSync(strategy, regexRules);
      return { data: null, status: 'success', message: 'Sync complete' };
    } catch (error) {
      return { data: null, status: 'error', message: 'Sync failed' };
    }
  }
};