import express from "express";
import { EncryptedTodoService } from "./todo-service.js";
import { WebSocketServer, WebSocket } from "ws";
import http from "http";
import "dotenv/config";

const app = express();
const server = http.createServer(app);
const wss = new WebSocketServer({ server });
const todoService = new EncryptedTodoService();

// Store active WebSocket connections
const connections = new Map();

// WebSocket connection handler
wss.on("connection", (ws, req) => {
  const userId = req.url.split("?userId=")[1];
  if (userId) {
    connections.set(userId, ws);
    console.log(`User ${userId} connected`);

    // Send initial user list
    ws.send(
      JSON.stringify({
        type: "users",
        data: Array.from(todoService.users.keys()),
      }),
    );

    ws.on("close", () => {
      connections.delete(userId);
      console.log(`User ${userId} disconnected`);
    });
  }
});

// Broadcast to all connected clients
function broadcast(message) {
  const messageStr = JSON.stringify(message);
  connections.forEach((ws) => {
    if (ws.readyState === WebSocket.OPEN) {
      ws.send(messageStr);
    }
  });
}

// Broadcast to specific user
function broadcastToUser(userId, message) {
  const ws = connections.get(userId);
  console.log(
    `broadcastToUser called for ${userId}, connection exists: ${!!ws}, readyState: ${ws ? ws.readyState : "N/A"}`,
  );
  if (ws && ws.readyState === WebSocket.OPEN) {
    console.log(
      `✓ Sending WebSocket message to ${userId}:`,
      message.type,
      JSON.stringify(message.data),
    );
    ws.send(JSON.stringify(message));
  } else {
    console.log(
      `✗ WebSocket not available for user ${userId} - connection: ${!!ws}, readyState: ${ws ? ws.readyState : "N/A"}`,
    );
  }
}

app.use(express.json());
app.use(express.static("public"));

// Create user
app.post("/api/users", (req, res) => {
  try {
    const { userId } = req.body;
    const user = todoService.createUser(userId);
    broadcast({ type: "users", data: todoService.getAllUsers() });
    res.json(user);
  } catch (error) {
    res.status(400).json({ error: error.message });
  }
});

// Get all users
app.get("/api/users", (req, res) => {
  try {
    const users = todoService.getAllUsers();
    res.json(users);
  } catch (error) {
    res.status(400).json({ error: error.message });
  }
});

// Add todo
app.post("/api/users/:userId/todos", (req, res) => {
  try {
    const { userId } = req.params;
    const { text } = req.body;
    const todoGroupId = todoService.addTodo(userId, text);
    const todo = todoService.getTodo(userId, todoGroupId);
    broadcastToUser(userId, { type: "todo_added", data: todo });
    res.json({ id: todoGroupId });
  } catch (error) {
    res.status(400).json({ error: error.message });
  }
});

// Get todos
app.get("/api/users/:userId/todos", (req, res) => {
  try {
    const { userId } = req.params;
    const todos = todoService.getTodos(userId);
    res.json(todos);
  } catch (error) {
    res.status(400).json({ error: error.message });
  }
});

// Get encrypted todos
app.get("/api/users/:userId/todos/encrypted", (req, res) => {
  try {
    const { userId } = req.params;
    const todos = todoService.getTodos(userId);
    const encryptedTodos = todos.map((todo) => {
      const row = todoService.db
        .prepare(
          "SELECT encrypted, createdAt FROM todos WHERE todoGroupId = ? AND userId = ?",
        )
        .get(todo.id, userId);

      if (!row) {
        console.warn(
          `No encrypted data found for todo ${todo.id} and user ${userId}`,
        );
        return {
          id: todo.id,
          encrypted: { body: "Encryption data not available" },
          createdAt: todo.createdAt,
        };
      }

      return {
        id: todo.id,
        encrypted: JSON.parse(row.encrypted),
        createdAt: row.createdAt,
      };
    });
    res.json(encryptedTodos);
  } catch (error) {
    console.error("Error in encrypted todos endpoint:", error);
    res.status(400).json({ error: error.message });
  }
});

// Delete todo
app.delete("/api/users/:userId/todos/:todoGroupId", (req, res) => {
  try {
    const { userId, todoGroupId } = req.params;
    const { deletedIds, affectedUsers } = todoService.deleteTodo(
      userId,
      todoGroupId,
    );

    // Broadcast deletion to all affected users
    console.log(`Broadcasting deletion to users: ${affectedUsers.join(", ")}`);
    affectedUsers.forEach((affectedUserId) => {
      deletedIds.forEach((deletedId) => {
        console.log(
          `Sending todo_deleted event for todo ${deletedId} to user ${affectedUserId}`,
        );
        broadcastToUser(affectedUserId, {
          type: "todo_deleted",
          data: { id: deletedId, deletedBy: userId },
        });
      });
    });

    res.json({ success: true });
  } catch (error) {
    res.status(400).json({ error: error.message });
  }
});

// Share todo
app.post("/api/users/:userId/todos/:todoGroupId/share", (req, res) => {
  try {
    const { userId, todoGroupId } = req.params;
    const { recipientId } = req.body;
    if (!recipientId) {
      return res.status(400).json({ error: "Recipient ID is required" });
    }
    const sharedTodoGroupId = todoService.shareTodo(
      userId,
      todoGroupId,
      recipientId,
    );
    const sharedTodo = todoService.getTodo(recipientId, sharedTodoGroupId);
    broadcastToUser(recipientId, { type: "todo_shared", data: sharedTodo });

    // Also notify the original user that the todo was shared
    broadcastToUser(userId, {
      type: "todo_share_confirmed",
      data: { todoGroupId, sharedWith: recipientId },
    });

    res.json({ success: true });
  } catch (error) {
    res.status(400).json({ error: error.message });
  }
});

// Update todo completion status
app.patch("/api/users/:userId/todos/:todoGroupId", (req, res) => {
  try {
    const { userId, todoGroupId } = req.params;
    const { completed } = req.body;

    console.log(
      `PATCH request: user ${userId} updating todo ${todoGroupId} to completed=${completed}`,
    );

    const affectedUsers = todoService.updateTodoStatus(
      userId,
      todoGroupId,
      completed,
    );

    console.log(`updateTodoStatus returned affected users:`, affectedUsers);

    // Broadcast update to all affected users
    console.log(
      `Broadcasting todo update to users: ${affectedUsers.join(", ")}`,
    );
    affectedUsers.forEach((affectedUserId) => {
      console.log(
        `Sending todo_updated event for todo ${todoGroupId} to user ${affectedUserId}`,
      );
      const message = {
        type: "todo_updated",
        data: { id: todoGroupId, completed, updatedBy: userId },
      };
      console.log(
        `Message being sent to ${affectedUserId}:`,
        JSON.stringify(message),
      );
      broadcastToUser(affectedUserId, message);
    });

    res.json({ success: true });
  } catch (error) {
    console.error(`Error updating todo status:`, error);
    res.status(400).json({ error: error.message });
  }
});

const PORT = process.env.PORT || 3000;
server.listen(PORT, () => {
  console.log(`Server running on port ${PORT}`);
});