/**
 * TASKMATE - Health Check Routes
 * ==============================
 * Server-Status und Health-Check Endpoints
 */

const express = require('express');
const router = express.Router();
const fs = require('fs');
const path = require('path');
const { getDb } = require('../database');
const backup = require('../utils/backup');

/**
 * GET /api/health
 * Einfacher Health-Check
 */
router.get('/', (req, res) => {
  try {
    // Datenbank-Check
    const db = getDb();
    db.prepare('SELECT 1').get();

    res.json({
      status: 'healthy',
      timestamp: new Date().toISOString()
    });
  } catch (error) {
    res.status(503).json({
      status: 'unhealthy',
      error: error.message,
      timestamp: new Date().toISOString()
    });
  }
});

/**
 * GET /api/health/detailed
 * Detaillierter Health-Check (mit Auth)
 */
router.get('/detailed', (req, res) => {
  try {
    const db = getDb();

    // Datenbank-Statistiken
    const userCount = db.prepare('SELECT COUNT(*) as count FROM users').get().count;
    const projectCount = db.prepare('SELECT COUNT(*) as count FROM projects WHERE archived = 0').get().count;
    const taskCount = db.prepare('SELECT COUNT(*) as count FROM tasks WHERE archived = 0').get().count;

    // Disk-Space für Uploads
    const uploadsDir = process.env.UPLOAD_DIR || path.join(__dirname, '..', 'uploads');
    let uploadsSize = 0;
    let uploadCount = 0;

    if (fs.existsSync(uploadsDir)) {
      const getDirectorySize = (dir) => {
        let size = 0;
        let count = 0;
        const files = fs.readdirSync(dir);
        for (const file of files) {
          const filePath = path.join(dir, file);
          const stats = fs.statSync(filePath);
          if (stats.isDirectory()) {
            const subResult = getDirectorySize(filePath);
            size += subResult.size;
            count += subResult.count;
          } else {
            size += stats.size;
            count++;
          }
        }
        return { size, count };
      };
      const result = getDirectorySize(uploadsDir);
      uploadsSize = result.size;
      uploadCount = result.count;
    }

    // Letzte Backups
    const backups = backup.listBackups().slice(0, 5);

    // Memory Usage
    const memUsage = process.memoryUsage();

    res.json({
      status: 'healthy',
      timestamp: new Date().toISOString(),
      uptime: Math.floor(process.uptime()),
      database: {
        users: userCount,
        projects: projectCount,
        tasks: taskCount
      },
      storage: {
        uploadCount,
        uploadsSizeMB: Math.round(uploadsSize / 1024 / 1024 * 100) / 100
      },
      backups: backups.map(b => ({
        name: b.name,
        sizeMB: Math.round(b.size / 1024 / 1024 * 100) / 100,
        created: b.created
      })),
      memory: {
        heapUsedMB: Math.round(memUsage.heapUsed / 1024 / 1024 * 100) / 100,
        heapTotalMB: Math.round(memUsage.heapTotal / 1024 / 1024 * 100) / 100,
        rssMB: Math.round(memUsage.rss / 1024 / 1024 * 100) / 100
      },
      environment: process.env.NODE_ENV || 'development'
    });
  } catch (error) {
    res.status(503).json({
      status: 'unhealthy',
      error: error.message,
      timestamp: new Date().toISOString()
    });
  }
});

/**
 * POST /api/health/backup
 * Manuelles Backup auslösen
 */
router.post('/backup', (req, res) => {
  try {
    const backupPath = backup.createBackup();

    if (backupPath) {
      res.json({
        message: 'Backup erfolgreich erstellt',
        path: path.basename(backupPath)
      });
    } else {
      res.status(500).json({ error: 'Backup fehlgeschlagen' });
    }
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

/**
 * GET /api/health/backups
 * Liste aller Backups
 */
router.get('/backups', (req, res) => {
  try {
    const backups = backup.listBackups();

    res.json(backups.map(b => ({
      name: b.name,
      sizeMB: Math.round(b.size / 1024 / 1024 * 100) / 100,
      created: b.created
    })));
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

module.exports = router;