import express from "express";
import { createServer as createViteServer } from "vite";
import { createProxyMiddleware } from "http-proxy-middleware";
import Database from "better-sqlite3";
import path from "path";
import { fileURLToPath } from "url";

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

const db = new Database("tasks.db");

// Initiera databasen
db.exec(`
  CREATE TABLE IF NOT EXISTS users (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    name TEXT NOT NULL UNIQUE,
    color TEXT NOT NULL,
    avatar TEXT DEFAULT 'UserIcon'
  );

  CREATE TABLE IF NOT EXISTS tasks (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    title TEXT NOT NULL,
    description TEXT,
    status TEXT NOT NULL CHECK (status IN ('pending', 'in_progress', 'completed')),
    points INTEGER DEFAULT 0,
    user_id INTEGER,
    is_recurring BOOLEAN DEFAULT 0,
    recurrence_period TEXT,
    due_date DATETIME,
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (user_id) REFERENCES users(id)
  );
`);

// Migreringar (för säkerhets skull)
try { db.prepare("ALTER TABLE tasks ADD COLUMN recurrence_period TEXT").run(); } catch (e) {}
try { db.prepare("ALTER TABLE users ADD COLUMN avatar TEXT DEFAULT 'UserIcon'").run(); } catch (e) {}

async function startServer() {
  const app = express();

  const BACKEND_URL = process.env.VITE_API_BASE_URL;

  if (BACKEND_URL) {
    console.log(`Proxying /api requests to ${BACKEND_URL}`);
    app.use(createProxyMiddleware({
      target: BACKEND_URL,
      changeOrigin: true,
      pathFilter: "/api",
    }));
  }

  app.use(express.json());

  // API-rutter
  app.get("/api/users", (req, res) => {
    const users = db.prepare("SELECT * FROM users").all();
    res.json(users);
  });

  app.post("/api/users", (req, res) => {
    const { name, color, avatar } = req.body;
    try {
      const info = db.prepare("INSERT INTO users (name, color, avatar) VALUES (?, ?, ?)").run(name, color, avatar || 'UserIcon');
      res.json({ id: info.lastInsertRowid, name, color, avatar: avatar || 'UserIcon' });
    } catch (e) {
      res.status(400).json({ error: "Användaren finns redan" });
    }
  });

  app.get("/api/tasks", (req, res) => {
    const tasks = db.prepare(`
      SELECT tasks.*, users.name as user_name, users.color as user_color, users.avatar as user_avatar 
      FROM tasks 
      LEFT JOIN users ON tasks.user_id = users.id
    `).all();
    res.json(tasks);
  });

  app.post("/api/tasks", (req, res) => {
    const { title, description, status, points, user_id, is_recurring, recurrence_period, due_date } = req.body;
    const info = db.prepare(`
      INSERT INTO tasks (title, description, status, points, user_id, is_recurring, recurrence_period, due_date) 
      VALUES (?, ?, ?, ?, ?, ?, ?, ?)
    `).run(title, description, status || 'pending', points || 0, user_id || null, is_recurring ? 1 : 0, recurrence_period || null, due_date || null);
    res.json({ id: info.lastInsertRowid, ...req.body });
  });

  app.patch("/api/tasks/:id", (req, res) => {
    const { id } = req.params;
    const { status, user_id } = req.body;
    const existingTask = db.prepare("SELECT * FROM tasks WHERE id = ?").get(id) as any;
    if (!existingTask) return res.status(404).json({ error: "Hittade inte uppgiften" });

    const updates = Object.keys(req.body).map(key => `${key} = ?`).join(", ");
    const values = Object.values(req.body);
    db.prepare(`UPDATE tasks SET ${updates} WHERE id = ?`).run(...values, id);

    if (status === 'completed' && existingTask.is_recurring && existingTask.recurrence_period && existingTask.due_date) {
      const nextDueDate = new Date(existingTask.due_date);
      if (existingTask.recurrence_period === 'daily') nextDueDate.setDate(nextDueDate.getDate() + 1);
      else if (existingTask.recurrence_period === 'weekly') nextDueDate.setDate(nextDueDate.getDate() + 7);
      else if (existingTask.recurrence_period === 'biweekly') nextDueDate.setDate(nextDueDate.getDate() + 14);
      else if (existingTask.recurrence_period === 'monthly') nextDueDate.setMonth(nextDueDate.getMonth() + 1);

      db.prepare(`
        INSERT INTO tasks (title, description, status, points, user_id, is_recurring, recurrence_period, due_date) 
        VALUES (?, ?, ?, ?, ?, ?, ?, ?)
      `).run(existingTask.title, existingTask.description, 'pending', existingTask.points, null, 1, existingTask.recurrence_period, nextDueDate.toISOString());
    }
    res.json({ success: true });
  });

  app.delete("/api/tasks/:id", (req, res) => {
    db.prepare("DELETE FROM tasks WHERE id = ?").run(req.params.id);
    res.json({ success: true });
  });

  // Vite integration
  if (process.env.NODE_ENV !== "production") {
    const vite = await createViteServer({
      server: { middlewareMode: true },
      appType: "spa",
    });
    app.use(vite.middlewares);
  } else {
    app.use(express.static(path.join(__dirname, "dist")));
    app.get("/{*path}", (req: any, res: any) => res.sendFile(path.join(__dirname, "dist", "index.html")));
  }

  const PORT = 3000;
  app.listen(PORT, "0.0.0.0", () => {
    console.log(`Server körs på http://localhost:${PORT}`);
  });
}

startServer();