import { Server as SocketIOServer, Socket } from 'socket.io';
import { upsertPixelsWithConflictResolution, getAllPixels, db, validatePixel } from './database';
import { Cursor, Pixel } from '../shared/types';
import passport from 'passport';

function generateRandomColor(): string {
  const colors = [
    '#FF6B6B', '#4ECDC4', '#45B7D1', '#96CEB4', '#FFEAA7',
    '#DDA0DD', '#98D8C8', '#F7DC6F', '#BB8FCE', '#85C1E2'
  ];
  return colors[Math.floor(Math.random() * colors.length)];
}

interface UserSocket extends Socket {
  userId: string;
  username: string;
  color: string;
  user?: any;
}

interface PaintRequest {
  pixels: Pixel[];
  timestamp: number;
}

interface PaintAck {
  success: boolean;
  saved: number;
  conflicts: number;
  pixels?: Pixel[];
  message?: string;
}

function getUserById(userId: number) {
  try {
    const stmt = db.prepare('SELECT * FROM users WHERE id = ?');
    return stmt.get(userId);
  } catch (error) {
    console.error('Error fetching user:', error);
    return null;
  }
}

export function setupSocketIO(io: SocketIOServer): void {
  const connectedUsers = new Map<string, { x: number; y: number; color: string; username: string; userId: string }>();
  
  io.on('connection', (socket: Socket) => {
    const userSocket = socket as UserSocket;
    
    socket.on('join-canvas', (token: string) => {
      try {
        const decoded = JSON.parse(Buffer.from(token, 'base64').toString());
        
        if (Date.now() - decoded.timestamp > 5 * 60 * 1000) {
          socket.emit('error', 'Token expired');
          socket.disconnect();
          return;
        }
        
        const userData = getUserById(decoded.userId);
        if (userData) {
          userSocket.user = userData;
          const userId = `auth_${userData.id}`;
          const username = userData.username || userData.display_name;
          const color = generateRandomColor();
          
          connectedUsers.set(userId, {
            x: 0,
            y: 0,
            color: color,
            username: username,
            userId: userData.id.toString()
          });
          
          socket.emit('canvas-state', getAllPixels());
          socket.emit('cursor-update', Array.from(connectedUsers.values()));
          socket.emit('auth-success', { user: userData });
          
          socket.broadcast.emit('cursor-update', Array.from(connectedUsers.values()));
          
          socket.on('cursor-move', (cursor: Cursor) => {
            const user = connectedUsers.get(userId);
            if (user) {
              user.x = cursor.x;
              user.y = cursor.y;
              socket.broadcast.emit('cursor-update', Array.from(connectedUsers.values()));
            }
          });
          
          socket.on('paint-pixels', async (request: PaintRequest, callback: (ack: PaintAck) => void) => {
            try {
              if (!userSocket.user) {
                const ack: PaintAck = { success: false, saved: 0, conflicts: 0, message: 'Authentication required' };
                callback(ack);
                return;
              }
              
              const { pixels, timestamp } = request;
              
              if (!Array.isArray(pixels) || pixels.length === 0) {
                const ack: PaintAck = { success: false, saved: 0, conflicts: 0, message: 'Invalid pixels data' };
                callback(ack);
                return;
              }
              
              for (const pixel of pixels) {
                const validationError = validatePixel(pixel);
                if (validationError) {
                  const ack: PaintAck = { success: false, saved: 0, conflicts: 0, message: validationError };
                  callback(ack);
                  return;
                }
              }
              
              const userIdNum = typeof userData.id === 'number' ? userData.id : parseInt(userData.id, 10);
              const result = upsertPixelsWithConflictResolution(
                pixels.map(p => ({ ...p, userId: userIdNum })),
                timestamp || 0
              );
              
              if (result.saved > 0) {
                socket.broadcast.emit('canvas-update', { pixels });
              }
              
              const ack: PaintAck = {
                success: true,
                saved: result.saved,
                conflicts: result.conflicts,
                pixels: result.conflicts > 0 ? pixels : undefined
              };
              callback(ack);
            } catch (error) {
              console.error('Error saving pixels:', error);
              const ack: PaintAck = { success: false, saved: 0, conflicts: 0, message: 'Failed to save pixels' };
              callback(ack);
            }
          });
          
          socket.on('disconnect', () => {
            connectedUsers.delete(userId);
            socket.broadcast.emit('cursor-update', Array.from(connectedUsers.values()));
          });
          
        } else {
          console.error('User not found for token:', decoded.userId);
          socket.emit('error', 'Invalid user');
          socket.disconnect();
        }
      } catch (error) {
        console.error('Token verification failed:', error);
        socket.emit('error', 'Invalid token');
        socket.disconnect();
      }
    });
  });
}