<?php
/**
 * Application Logger
 * Tracks all application actions for reporting and auditing
 */

class ApplicationLogger {
    private $logFile;
    private $config;

    public function __construct() {
        $appConfig = require __DIR__ . '/config.php';
        $this->config = $appConfig;

        // Create logs directory if it doesn't exist
        $logsDir = __DIR__ . '/logs';
        if (!file_exists($logsDir)) {
            mkdir($logsDir, 0755, true);
        }

        $this->logFile = $logsDir . '/application.log';
    }

    /**
     * Log action with structured data
     */
    public function log($action, $user, $data = [], $status = 'success') {
        $logEntry = [
            'timestamp' => date('Y-m-d H:i:s'),
            'action' => $action,
            'user_email' => $user['email'] ?? 'unknown',
            'user_name' => $user['name'] ?? 'unknown',
            'status' => $status,
            'data' => $data,
            'ip_address' => $_SERVER['REMOTE_ADDR'] ?? 'unknown',
            'user_agent' => $_SERVER['HTTP_USER_AGENT'] ?? 'unknown'
        ];

        $logLine = json_encode($logEntry) . "\n";

        // Append to log file
        file_put_contents($this->logFile, $logLine, FILE_APPEND | LOCK_EX);

        // Also log to PHP error log for debugging
        error_log('[APP LOG] ' . $action . ' - ' . $status . ' - ' . ($user['email'] ?? 'unknown'));

        return $logEntry;
    }

    /**
     * Log Master Asset Submission
     */
    public function logAssetSubmission($user, $boxId, $masterCampaignNumber, $dates, $status = 'success', $error = null) {
        return $this->log('master_asset_submission', $user, [
            'box_id' => $boxId,
            'master_campaign_number' => $masterCampaignNumber,
            'supply_date' => $dates['supply'] ?? null,
            'live_date' => $dates['live'] ?? null,
            'end_date' => $dates['end'] ?? null,
            'error' => $error
        ], $status);
    }

    /**
     * Log Global to Local Transformation
     */
    public function logGlobalToLocal($user, $campaignNumber, $businessUnit, $inputRows, $outputFiles, $status = 'success', $error = null) {
        return $this->log('global_to_local_transform', $user, [
            'campaign_number' => $campaignNumber,
            'business_unit' => $businessUnit,
            'input_rows' => $inputRows,
            'output_file_count' => $outputFiles,
            'total_output_rows' => $inputRows * $outputFiles,
            'error' => $error
        ], $status);
    }

    /**
     * Log Box Upload
     */
    public function logBoxUpload($user, $fileCount, $folderId, $status = 'success', $error = null) {
        return $this->log('box_upload', $user, [
            'file_count' => $fileCount,
            'folder_id' => $folderId,
            'error' => $error
        ], $status);
    }

    /**
     * Log OMG API Call
     */
    public function logOMGAPICall($user, $campaignNumber, $businessArea, $businessUnit, $status = 'success', $error = null) {
        return $this->log('omg_api_lookup', $user, [
            'campaign_number' => $campaignNumber,
            'business_area' => $businessArea,
            'business_unit' => $businessUnit,
            'error' => $error
        ], $status);
    }

    /**
     * Get recent logs
     */
    public function getRecentLogs($limit = 100) {
        if (!file_exists($this->logFile)) {
            return [];
        }

        $lines = file($this->logFile, FILE_IGNORE_NEW_LINES);
        $lines = array_reverse($lines);  // Most recent first
        $lines = array_slice($lines, 0, $limit);

        $logs = [];
        foreach ($lines as $line) {
            $log = json_decode($line, true);
            if ($log) {
                $logs[] = $log;
            }
        }

        return $logs;
    }

    /**
     * Get logs by action type
     */
    public function getLogsByAction($action, $limit = 100) {
        $allLogs = $this->getRecentLogs(1000);

        $filtered = array_filter($allLogs, function($log) use ($action) {
            return $log['action'] === $action;
        });

        return array_slice(array_values($filtered), 0, $limit);
    }

    /**
     * Get logs by user
     */
    public function getLogsByUser($userEmail, $limit = 100) {
        $allLogs = $this->getRecentLogs(1000);

        $filtered = array_filter($allLogs, function($log) use ($userEmail) {
            return $log['user_email'] === $userEmail;
        });

        return array_slice(array_values($filtered), 0, $limit);
    }

    /**
     * Generate report statistics
     */
    public function getStatistics($startDate = null, $endDate = null) {
        $allLogs = $this->getRecentLogs(10000);

        // Filter by date if provided
        if ($startDate || $endDate) {
            $allLogs = array_filter($allLogs, function($log) use ($startDate, $endDate) {
                $timestamp = strtotime($log['timestamp']);
                if ($startDate && $timestamp < strtotime($startDate)) return false;
                if ($endDate && $timestamp > strtotime($endDate)) return false;
                return true;
            });
        }

        $stats = [
            'total_actions' => count($allLogs),
            'by_action' => [],
            'by_user' => [],
            'by_status' => [],
            'errors' => []
        ];

        foreach ($allLogs as $log) {
            // Count by action
            $action = $log['action'];
            $stats['by_action'][$action] = ($stats['by_action'][$action] ?? 0) + 1;

            // Count by user
            $user = $log['user_email'];
            $stats['by_user'][$user] = ($stats['by_user'][$user] ?? 0) + 1;

            // Count by status
            $status = $log['status'];
            $stats['by_status'][$status] = ($stats['by_status'][$status] ?? 0) + 1;

            // Collect errors
            if ($status === 'error') {
                $stats['errors'][] = [
                    'timestamp' => $log['timestamp'],
                    'action' => $log['action'],
                    'user' => $log['user_email'],
                    'error' => $log['data']['error'] ?? 'Unknown error'
                ];
            }
        }

        return $stats;
    }
}