/**
 * Production-Ready Node.js API Server
 * For testing git serverless deployment
 */

const express = require('express');
const cors = require('cors');
const helmet = require('helmet');
const morgan = require('morgan');
const compression = require('compression');
const { v4: uuidv4 } = require('uuid');

// Load environment variables
require('dotenv').config();

const app = express();
const PORT = process.env.PORT || 8080;
const NODE_ENV = process.env.NODE_ENV || 'development';

// ===========================================
// Middleware
// ===========================================
app.use(helmet());                    // Security headers
app.use(cors());                      // CORS support
app.use(compression());               // Gzip compression
app.use(morgan('combined'));          // Request logging
app.use(express.json());              // Parse JSON bodies
app.use(express.urlencoded({ extended: true }));

// ===========================================
// In-Memory Database (for testing)
// ===========================================
const database = {
  users: [
    { id: '1', name: 'John Doe', email: 'john@example.com', createdAt: new Date().toISOString() },
    { id: '2', name: 'Jane Smith', email: 'jane@example.com', createdAt: new Date().toISOString() },
  ],
  tasks: [
    { id: '1', userId: '1', title: 'Complete project', status: 'pending', createdAt: new Date().toISOString() },
    { id: '2', userId: '1', title: 'Review PR', status: 'done', createdAt: new Date().toISOString() },
  ]
};

// ===========================================
// Health Check Routes
// ===========================================
app.get('/', (req, res) => {
  res.json({
    service: 'test-git-fcz5',
    version: '1.0.0',
    status: 'healthy',
    timestamp: new Date().toISOString(),
    environment: NODE_ENV,
  });
});

app.get('/health', (req, res) => {
  res.json({
    status: 'ok',
    uptime: process.uptime(),
    timestamp: new Date().toISOString(),
  });
});

app.get('/ready', (req, res) => {
  res.json({ ready: true });
});

// ===========================================
// Environment Info Route (for testing)
// ===========================================
app.get('/api/env', (req, res) => {
  res.json({
    message: 'Environment variables (for testing config overrides)',
    environment: {
      NODE_ENV: process.env.NODE_ENV || 'not-set',
      PORT: process.env.PORT || 'not-set',
      // Boltic system variables
      BOLT_APPLICATION_NAME: process.env.BOLT_APPLICATION_NAME || 'not-set',
      BOLT_APPLICATION_SLUG: process.env.BOLT_APPLICATION_SLUG || 'not-set',
      BOLT_APPLICATION_REGION_ID: process.env.BOLT_APPLICATION_REGION_ID || 'not-set',
      // Custom env vars (set from UI or boltic.yaml)
      API_KEY: process.env.API_KEY ? '***hidden***' : 'not-set',
      DATABASE_URL: process.env.DATABASE_URL ? '***hidden***' : 'not-set',
      CUSTOM_VAR: process.env.CUSTOM_VAR || 'not-set',
      UI_TEST_VAR: process.env.UI_TEST_VAR || 'not-set',
    },
    testInfo: {
      purpose: 'Verify environment variables from UI and boltic.yaml',
      configFormat: 'Check if serverlessConfig overrides are applied',
    }
  });
});

// ===========================================
// Users API
// ===========================================
app.get('/api/users', (req, res) => {
  res.json({
    success: true,
    data: database.users,
    total: database.users.length,
  });
});

app.get('/api/users/:id', (req, res) => {
  const user = database.users.find(u => u.id === req.params.id);
  if (!user) {
    return res.status(404).json({ success: false, error: 'User not found' });
  }
  res.json({ success: true, data: user });
});

app.post('/api/users', (req, res) => {
  const { name, email } = req.body;
  if (!name || !email) {
    return res.status(400).json({ success: false, error: 'Name and email are required' });
  }
  
  const newUser = {
    id: uuidv4(),
    name,
    email,
    createdAt: new Date().toISOString(),
  };
  database.users.push(newUser);
  
  res.status(201).json({ success: true, data: newUser });
});

app.put('/api/users/:id', (req, res) => {
  const index = database.users.findIndex(u => u.id === req.params.id);
  if (index === -1) {
    return res.status(404).json({ success: false, error: 'User not found' });
  }
  
  database.users[index] = { ...database.users[index], ...req.body };
  res.json({ success: true, data: database.users[index] });
});

app.delete('/api/users/:id', (req, res) => {
  const index = database.users.findIndex(u => u.id === req.params.id);
  if (index === -1) {
    return res.status(404).json({ success: false, error: 'User not found' });
  }
  
  const deleted = database.users.splice(index, 1);
  res.json({ success: true, data: deleted[0] });
});

// ===========================================
// Tasks API
// ===========================================
app.get('/api/tasks', (req, res) => {
  const { userId, status } = req.query;
  let tasks = [...database.tasks];
  
  if (userId) tasks = tasks.filter(t => t.userId === userId);
  if (status) tasks = tasks.filter(t => t.status === status);
  
  res.json({
    success: true,
    data: tasks,
    total: tasks.length,
  });
});

app.post('/api/tasks', (req, res) => {
  const { userId, title } = req.body;
  if (!userId || !title) {
    return res.status(400).json({ success: false, error: 'userId and title are required' });
  }
  
  const newTask = {
    id: uuidv4(),
    userId,
    title,
    status: 'pending',
    createdAt: new Date().toISOString(),
  };
  database.tasks.push(newTask);
  
  res.status(201).json({ success: true, data: newTask });
});

app.patch('/api/tasks/:id/status', (req, res) => {
  const { status } = req.body;
  const validStatuses = ['pending', 'in-progress', 'done'];
  
  if (!status || !validStatuses.includes(status)) {
    return res.status(400).json({ 
      success: false, 
      error: `Invalid status. Must be one of: ${validStatuses.join(', ')}` 
    });
  }
  
  const task = database.tasks.find(t => t.id === req.params.id);
  if (!task) {
    return res.status(404).json({ success: false, error: 'Task not found' });
  }
  
  task.status = status;
  res.json({ success: true, data: task });
});

// ===========================================
// Echo/Debug Route (for testing)
// ===========================================
app.all('/api/echo', (req, res) => {
  res.json({
    method: req.method,
    path: req.path,
    query: req.query,
    headers: req.headers,
    body: req.body,
    timestamp: new Date().toISOString(),
  });
});

// ===========================================
// 404 Handler
// ===========================================
app.use((req, res) => {
  res.status(404).json({
    success: false,
    error: 'Not Found',
    path: req.path,
  });
});

// ===========================================
// Error Handler
// ===========================================
app.use((err, req, res, next) => {
  console.error('Error:', err);
  res.status(500).json({
    success: false,
    error: NODE_ENV === 'production' ? 'Internal Server Error' : err.message,
  });
});

// ===========================================
// Start Server
// ===========================================
app.listen(PORT, '0.0.0.0', () => {
  console.log('========================================');
  console.log(`🚀 Server started successfully!`);
  console.log(`📍 Environment: ${NODE_ENV}`);
  console.log(`🌐 Listening on: http://0.0.0.0:${PORT}`);
  console.log(`💚 Health check: http://0.0.0.0:${PORT}/health`);
  console.log('========================================');
});

module.exports = app;