/**
 * Log Management API Routes (CWE-53 Compliance)
 * Admin-only endpoints for log retention, archival, and integrity
 */

const express = require('express');
const router = express.Router();
const { authenticate } = require('../middleware/auth');
const { requirePermission } = require('../middleware/rbac');
const { readLimiter, modifyLimiter } = require('../middleware/rateLimiter');
const logManagement = require('../jobs/logManagement');
const SecurityAuditLogger = require('../utils/securityAudit');
const logger = require('../utils/logger');
const path = require('path');
const fs = require('fs').promises;

/**
 * GET /api/log-management/statistics
 * Get log management statistics
 */
router.get('/statistics',
  authenticate,
  requirePermission('security.view_audit'),
  readLimiter,
  async (req, res) => {
    try {
      const stats = await logManagement.getStatistics();
      
      await SecurityAuditLogger.logSensitiveDataAccess(req.user.userId, 'log_statistics', {
        ip: req.ip,
        userAgent: req.headers['user-agent']
      });
      
      res.json({
        success: true,
        data: stats
      });
    } catch (error) {
      logger.error('[LogManagement API] Error getting statistics:', error);
      res.status(500).json({
        success: false,
        message: 'Failed to get log statistics'
      });
    }
  }
);

/**
 * GET /api/log-management/archives
 * List available log archives
 */
router.get('/archives',
  authenticate,
  requirePermission('security.view_audit'),
  readLimiter,
  async (req, res) => {
    try {
      const archives = await logManagement.listArchives();
      
      await SecurityAuditLogger.logSensitiveDataAccess(req.user.userId, 'log_archives_list', {
        ip: req.ip,
        userAgent: req.headers['user-agent'],
        recordCount: archives.length
      });
      
      res.json({
        success: true,
        data: archives
      });
    } catch (error) {
      logger.error('[LogManagement API] Error listing archives:', error);
      res.status(500).json({
        success: false,
        message: 'Failed to list archives'
      });
    }
  }
);

/**
 * POST /api/log-management/cleanup
 * Manual trigger for log cleanup
 * Admin only
 */
router.post('/cleanup',
  authenticate,
  requirePermission('security.manage'),
  modifyLimiter,
  async (req, res) => {
    try {
      const { retentionDays } = req.body;
      const days = parseInt(retentionDays) || 90;
      
      if (days < 7) {
        return res.status(400).json({
          success: false,
          message: 'Retention days must be at least 7'
        });
      }
      
      const result = await logManagement.manualCleanup(days);
      
      await SecurityAuditLogger.logAdminActivity(req.user.userId, 'log_cleanup_manual', {
        ip: req.ip,
        userAgent: req.headers['user-agent'],
        retentionDays: days,
        ...result
      });
      
      res.json({
        success: true,
        message: `Deleted ${result.auditDeleted + result.aggregatedDeleted} old log entries`,
        data: result
      });
    } catch (error) {
      logger.error('[LogManagement API] Error during manual cleanup:', error);
      res.status(500).json({
        success: false,
        message: 'Failed to perform log cleanup'
      });
    }
  }
);

/**
 * POST /api/log-management/verify-integrity
 * Manual trigger for integrity verification
 * Admin only
 */
router.post('/verify-integrity',
  authenticate,
  requirePermission('security.view_audit'),
  modifyLimiter,
  async (req, res) => {
    try {
      const result = await logManagement.manualIntegrityCheck();
      
      if (!result) {
        return res.status(500).json({
          success: false,
          message: 'Integrity verification failed'
        });
      }
      
      await SecurityAuditLogger.logAdminActivity(req.user.userId, 'log_integrity_check', {
        ip: req.ip,
        userAgent: req.headers['user-agent'],
        verified: result.verified,
        tampered: result.tampered
      });
      
      res.json({
        success: true,
        message: result.tampered > 0 
          ? `⚠️ WARNING: ${result.tampered} tampered logs detected!`
          : `All ${result.verified} logs verified successfully`,
        data: result,
        alert: result.tampered > 0
      });
    } catch (error) {
      logger.error('[LogManagement API] Error during integrity check:', error);
      res.status(500).json({
        success: false,
        message: 'Failed to verify log integrity'
      });
    }
  }
);

/**
 * GET /api/log-management/archives/download/:filename
 * Download a log archive
 * Admin only
 */
router.get('/archives/download/:filename',
  authenticate,
  requirePermission('security.view_audit'),
  readLimiter,
  async (req, res) => {
    try {
      const { filename } = req.params;
      
      // Security: prevent path traversal
      if (filename.includes('..') || filename.includes('/') || filename.includes('\\')) {
        return res.status(400).json({
          success: false,
          message: 'Invalid filename'
        });
      }
      
      // Security: only allow .json.gz files
      if (!filename.endsWith('.json.gz')) {
        return res.status(400).json({
          success: false,
          message: 'Invalid file type'
        });
      }
      
      const archiveDir = path.join(__dirname, '../../data/log-archives');
      const filePath = path.join(archiveDir, filename);
      
      // Check if file exists
      try {
        await fs.access(filePath);
      } catch (error) {
        return res.status(404).json({
          success: false,
          message: 'Archive not found'
        });
      }
      
      // Log the access
      await SecurityAuditLogger.logSensitiveDataAccess(req.user.userId, 'log_archive_download', {
        ip: req.ip,
        userAgent: req.headers['user-agent'],
        filename,
        accessMethod: 'download'
      });
      
      // Send file
      res.download(filePath, filename);
    } catch (error) {
      logger.error('[LogManagement API] Error downloading archive:', error);
      res.status(500).json({
        success: false,
        message: 'Failed to download archive'
      });
    }
  }
);

/**
 * DELETE /api/log-management/archives/:filename
 * Delete a log archive
 * Admin only
 */
router.delete('/archives/:filename',
  authenticate,
  requirePermission('security.manage'),
  modifyLimiter,
  async (req, res) => {
    try {
      const { filename } = req.params;
      
      // Security: prevent path traversal
      if (filename.includes('..') || filename.includes('/') || filename.includes('\\')) {
        return res.status(400).json({
          success: false,
          message: 'Invalid filename'
        });
      }
      
      // Security: only allow .json.gz files
      if (!filename.endsWith('.json.gz')) {
        return res.status(400).json({
          success: false,
          message: 'Invalid file type'
        });
      }
      
      const archiveDir = path.join(__dirname, '../../data/log-archives');
      const filePath = path.join(archiveDir, filename);
      
      // Check if file exists
      try {
        await fs.access(filePath);
      } catch (error) {
        return res.status(404).json({
          success: false,
          message: 'Archive not found'
        });
      }
      
      // Delete file
      await fs.unlink(filePath);
      
      // Log the deletion
      await SecurityAuditLogger.logAdminActivity(req.user.userId, 'log_archive_deleted', {
        ip: req.ip,
        userAgent: req.headers['user-agent'],
        filename
      });
      
      res.json({
        success: true,
        message: 'Archive deleted successfully'
      });
    } catch (error) {
      logger.error('[LogManagement API] Error deleting archive:', error);
      res.status(500).json({
        success: false,
        message: 'Failed to delete archive'
      });
    }
  }
);

module.exports = router;