const request = require("supertest");
const socketIoClient = require("socket.io-client");
const jwt = require("jsonwebtoken");
const { createServer } = require("http");
const { Server } = require("socket.io");

// Create test server with Socket.IO
const createTestServer = () => {
  const app = require("express")();
  const server = createServer(app);
  const io = new Server(server, {
    cors: {
      origin: "*",
      methods: ["GET", "POST"]
    }
  });
  
  // Socket.IO authentication middleware
  io.use((socket, next) => {
    const token = socket.handshake.auth.token;
    if (!token) {
      return next(new Error("Authentication error"));
    }
    
    try {
      const decoded = jwt.verify(token, process.env.JWT_SECRET || "test_secret");
      socket.userId = decoded.user.id;
      next();
    } catch (err) {
      next(new Error("Authentication error"));
    }
  });
  
  io.on("connection", (socket) => {
    console.log("User connected:", socket.userId);
    
    // Join event rooms
    socket.on("joinEvent", (eventId) => {
      socket.join(`event_${eventId}`);
      socket.emit("joinedEvent", { eventId });
    });
    
    // Leave event rooms
    socket.on("leaveEvent", (eventId) => {
      socket.leave(`event_${eventId}`);
      socket.emit("leftEvent", { eventId });
    });
    
    // Handle event updates
    socket.on("eventUpdate", (data) => {
      socket.to(`event_${data.eventId}`).emit("eventUpdate", data);
    });
    
    // Handle new posts
    socket.on("newPost", (data) => {
      socket.broadcast.emit("newPost", data);
    });
    
    // Handle task updates
    socket.on("taskUpdate", (data) => {
      socket.broadcast.emit("taskUpdate", data);
    });
    
    socket.on("disconnect", () => {
      console.log("User disconnected:", socket.userId);
    });
  });
  
  return { server, io };
};

describe("Socket.IO Real-time Features", () => {
  let server;
  let io;
  let clientSocket;
  let testUser;
  let authToken;

  beforeAll(async () => {
    // Create test server
    const testServer = createTestServer();
    server = testServer.server;
    io = testServer.io;
    
    // Start server on random port
    await new Promise((resolve) => {
      server.listen(0, resolve);
    });

    // Create mock test user
    testUser = {
      _id: "test_user_123",
      name: "Test User",
      email: "test@example.com"
    };

    // Generate auth token
    authToken = jwt.sign(
      { user: { id: testUser._id } },
      process.env.JWT_SECRET || "test_secret"
    );
  });

  afterAll(async () => {
    if (clientSocket) {
      clientSocket.disconnect();
    }
    io.close();
    server.close();
  });

  beforeEach((done) => {
    // Connect client socket with authentication
    clientSocket = socketIoClient(`http://localhost:${server.address().port}`, {
      auth: { token: authToken },
    });

    clientSocket.on("connect", () => {
      done();
    });

    clientSocket.on("connect_error", (err) => {
      done(err);
    });
  });

  afterEach(() => {
    if (clientSocket && clientSocket.connected) {
      clientSocket.disconnect();
    }
  });

  describe("Socket Authentication", () => {
    test("should connect with valid token", (done) => {
      expect(clientSocket.connected).toBe(true);
      done();
    });

    test("should reject connection with invalid token", (done) => {
      const invalidSocket = socketIoClient(
        `http://localhost:${server.address().port}`,
        {
          auth: { token: "invalid_token" },
        }
      );

      invalidSocket.on("connect_error", (err) => {
        expect(err.message).toBe("Authentication error");
        invalidSocket.disconnect();
        done();
      });
    });

    test("should reject connection without token", (done) => {
      const noTokenSocket = socketIoClient(
        `http://localhost:${server.address().port}`
      );

      noTokenSocket.on("connect_error", (err) => {
        expect(err.message).toBe("Authentication error");
        noTokenSocket.disconnect();
        done();
      });
    });
  });

  describe("Event Participation", () => {
    let testEvent;

    beforeEach(() => {
      testEvent = {
        _id: "test_event_123",
        title: "Test Event",
        description: "Test Description",
        date: new Date(Date.now() + 86400000), // Tomorrow
        location: "Test Location",
        participants: [],
      };
    });

    test("should join event room", (done) => {
      clientSocket.emit("joinEvent", testEvent._id);

      clientSocket.on("joinedEvent", (data) => {
        expect(data.eventId).toBe(testEvent._id);
        done();
      });
    });

    test("should receive event updates in room", (done) => {
      clientSocket.emit("joinEvent", testEvent._id);

      // Create another client to send updates to the room
      const anotherClient = socketIoClient(`http://localhost:${server.address().port}`, {
        auth: { token: authToken },
      });

      anotherClient.on("connect", () => {
        // Listen for updates from first client
        clientSocket.on("eventUpdate", (data) => {
          expect(data.message).toBe("Event status updated to ongoing");
          anotherClient.disconnect();
          done();
        });

        // Join the same event room
        anotherClient.emit("joinEvent", testEvent._id);

        // Send update from second client (will be broadcast to room)
        setTimeout(() => {
          anotherClient.emit("eventUpdate", {
            eventId: testEvent._id,
            message: "Event status updated to ongoing",
          });
        }, 100);
      });
    });

    test("should not receive updates for events not joined", (done) => {
      const anotherEventId = "another_event_456";

      // Listen for updates (should not receive any)
      let updateReceived = false;
      clientSocket.on("eventUpdate", () => {
        updateReceived = true;
      });

      // Send update for event not joined
      setTimeout(() => {
        clientSocket.emit("eventUpdate", {
          eventId: anotherEventId,
          message: "This should not be received",
        });

        // Check after delay that no update was received
        setTimeout(() => {
          expect(updateReceived).toBe(false);
          done();
        }, 100);
      }, 100);
    });
  });

  describe("Post Interactions", () => {
    let testPost;
    let testEvent;

    beforeEach(() => {
      testPost = {
        _id: "test_post_123",
        user: {
          userId: testUser._id,
          name: testUser.name,
        },
        content: "Test post content",
        likes: [],
        commentsCount: 0,
      };

      testEvent = {
        _id: "test_event_123",
        title: "Test Event",
        description: "Test Description",
        date: new Date(Date.now() + 86400000),
        location: "Test Location",
        participants: [],
      };
    });

    test("should broadcast new posts", (done) => {
      // Create another client to receive broadcasts
      const anotherClient = socketIoClient(`http://localhost:${server.address().port}`, {
        auth: { token: authToken },
      });

      anotherClient.on("connect", () => {
        // Listen for new posts
        anotherClient.on("newPost", (data) => {
          expect(data.content).toBe("Test broadcast post");
          anotherClient.disconnect();
          done();
        });

        // Send new post from first client
        clientSocket.emit("newPost", {
          content: "Test broadcast post",
          user: testUser
        });
      });
    });

    test("should handle multiple event joins", (done) => {
      const testEvent2 = {
        _id: "test_event_456",
        title: "Another Event",
        description: "Another Description",
        date: new Date(Date.now() + 86400000),
        location: "Another Location",
        participants: [],
      };

      let joinCount = 0;
      const checkJoins = () => {
        joinCount++;
        if (joinCount === 2) {
          done();
        }
      };

      clientSocket.on("joinedEvent", (data) => {
        checkJoins();
      });

      clientSocket.emit("joinEvent", testEvent._id);
      clientSocket.emit("joinEvent", testEvent2._id);
    });
  });

  describe("Connection Stability", () => {
    test("should handle disconnection gracefully", (done) => {
      // Simple test that disconnection doesn't throw errors
      expect(() => {
        clientSocket.disconnect();
      }).not.toThrow();
      
      setTimeout(() => {
        expect(clientSocket.connected).toBe(false);
        done();
      }, 100);
    });

    test("should maintain connection under load", async () => {
      const startTime = Date.now();
      const messageCount = 50; // Reduced for test stability
      
      for (let i = 0; i < messageCount; i++) {
        await new Promise((resolve) => {
          clientSocket.emit("eventUpdate", {
            eventId: `test_event_${i}`,
            message: `Test message ${i}`,
          });
          setTimeout(resolve, 10);
        });
      }
      
      const endTime = Date.now();
      const duration = endTime - startTime;
      
      // Should complete within reasonable time (less than 5 seconds)
      expect(duration).toBeLessThan(5000);
      expect(clientSocket.connected).toBe(true);
    });
  });

  describe("Concurrent Connections", () => {
    test("should handle multiple simultaneous connections", async () => {
      const clients = [];
      const connectionPromises = [];

      // Create 10 concurrent connections
      for (let i = 0; i < 10; i++) {
        const promise = new Promise((resolve) => {
          const client = socketIoClient(
            `http://localhost:${server.address().port}`,
            {
              auth: { token: authToken },
            }
          );

          client.on("connect", () => {
            clients.push(client);
            resolve();
          });

          client.on("connect_error", (err) => {
            resolve(err);
          });
        });

        connectionPromises.push(promise);
      }

      await Promise.all(connectionPromises);

      // All connections should succeed
      expect(clients.length).toBe(10);
      clients.forEach((client) => {
        expect(client.connected).toBe(true);
      });

      // Clean up
      clients.forEach((client) => client.disconnect());
    });
  });
});