<?php
require_once __DIR__ . '/../db/config.php';
require_once __DIR__ . '/../includes/functions.php';
require_once __DIR__ . '/../includes/WablasService.php';

// Enable error logging for cron
ini_set('log_errors', 1);
$logFile = __DIR__ . '/../storage/cron_debug.log';
ini_set('error_log', $logFile);

// Helper to log with timestamp
function cron_log($msg) {
    global $logFile;
    file_put_contents($logFile, "[" . date('Y-m-d H:i:s') . "] " . $msg . "\n", FILE_APPEND);
}

// Helper to format currency
function format_currency_custom($amount, $settings) {
    $symbol = $settings['currency_symbol'] ?? '$';
    $decimals = (int)($settings['currency_decimals'] ?? 3);
    $position = $settings['currency_position'] ?? 'after';
    
    $formatted = number_format((float)$amount, $decimals);
    return ($position === 'after') ? "$formatted $symbol" : "$symbol $formatted";
}

try {
    $settings = get_company_settings();
    
    if (empty($settings['whatsapp_report_enabled']) || empty($settings['whatsapp_report_number']) || empty($settings['whatsapp_report_time'])) {
        exit;
    }

    $timezone = !empty($settings['timezone']) ? $settings['timezone'] : 'UTC';
    date_default_timezone_set($timezone);

    $pdo = db();
    
    // Use UTC strategy for consistent querying
    // 1. Calculate Local Start/End of Today
    $nowDt = new DateTime('now', new DateTimeZone($timezone));
    
    $startLocal = clone $nowDt;
    $startLocal->setTime(0, 0, 0);
    
    $endLocal = clone $nowDt;
    $endLocal->setTime(23, 59, 59);
    
    // 2. Convert to UTC strings for DB query
    $startUtc = clone $startLocal;
    $startUtc->setTimezone(new DateTimeZone('UTC'));
    $strStartUtc = $startUtc->format('Y-m-d H:i:s');
    
    $endUtc = clone $endLocal;
    $endUtc->setTimezone(new DateTimeZone('UTC'));
    $strEndUtc = $endUtc->format('Y-m-d H:i:s');
    
    // 3. Set DB Session to UTC so it interprets our UTC strings correctly
    try {
        $pdo->exec("SET time_zone = '+00:00'");
    } catch (Exception $e) {
        cron_log("Warning: Could not set MySQL timezone to UTC: " . $e->getMessage());
    }

    $reportTime = $settings['whatsapp_report_time']; 
    $lastReportFile = __DIR__ . '/../storage/last_daily_report.txt';
    $lastReportDate = file_exists($lastReportFile) ? trim(file_get_contents($lastReportFile)) : '';

    // Check schedule relative to Local Time
    $targetTodayDt = clone $nowDt;
    $timeParts = explode(':', $reportTime);
    $targetTodayDt->setTime((int)$timeParts[0], (int)($timeParts[1] ?? 0), 0);
    
    $diffToday = $nowDt->getTimestamp() - $targetTodayDt->getTimestamp();
    
    // Run if within 15 mins of schedule AND not already run for this local date
    if ($diffToday >= 0 && $diffToday <= 900 && $lastReportDate !== $nowDt->format('Y-m-d')) {
        cron_log("Condition met: sending daily report for " . $nowDt->format('Y-m-d'));
        cron_log("Querying UTC Range: $strStartUtc to $strEndUtc");
        
        $todayDisplay = $nowDt->format('Y-m-d');
        $companyName = $settings['company_name'] ?? 'Company';

        // --- 1. Global Stats ---
        // Total Revenue
        $stmt = $pdo->prepare("SELECT SUM(total_amount) FROM orders WHERE created_at >= ? AND created_at <= ? AND status != 'cancelled'");
        $stmt->execute([$strStartUtc, $strEndUtc]);
        $totalRevenue = $stmt->fetchColumn() ?: 0;

        // Total Orders
        $stmt = $pdo->prepare("SELECT COUNT(*) FROM orders WHERE created_at >= ? AND created_at <= ? AND status != 'cancelled'");
        $stmt->execute([$strStartUtc, $strEndUtc]);
        $totalOrders = $stmt->fetchColumn() ?: 0;

        // --- 2. Build Message Header ---
        $message = "📊 *Daily Summary Report* 📊\n";
        $message .= "🏢 *" . $companyName . "*\n";
        $message .= "📅 Date: " . $todayDisplay . "\n";
        $message .= "--------------------------------\n";
        $message .= "🛒 *Total Orders:* " . $totalOrders . "\n";
        $message .= "💰 *Total Revenue:* " . format_currency_custom($totalRevenue, $settings) . "\n";

        // --- 3. Per-Outlet Stats ---
        // Fetch outlets dynamically from DB
        $stmtOutlets = $pdo->query("SELECT id, name, name_ar FROM outlets WHERE is_deleted = 0 ORDER BY id ASC");
        $outlets = $stmtOutlets->fetchAll();
        cron_log("Fetched " . count($outlets) . " outlets from database.");
        
        foreach ($outlets as $outlet) {
            $outletId = $outlet['id'];
            $outletName = !empty($outlet['name_ar']) ? $outlet['name_ar'] : $outlet['name'];

            // Outlet Revenue
            $stmtRev = $pdo->prepare("SELECT SUM(total_amount) FROM orders WHERE outlet_id = ? AND created_at >= ? AND created_at <= ? AND status != 'cancelled'");
            $stmtRev->execute([$outletId, $strStartUtc, $strEndUtc]);
            $outletRevenue = $stmtRev->fetchColumn() ?: 0;

            $message .= "\n🏪 *" . $outletName . " Total:* " . format_currency_custom($outletRevenue, $settings) . "\n";

            // Staff Breakdown
            $message .= "🧑‍🍳 *Staff Breakdown:*
";
            
            $stmtStaff = $pdo->prepare(" 
                SELECT u.username, u.full_name, COUNT(o.id) as order_count, SUM(o.total_amount) as revenue 
                FROM orders o 
                LEFT JOIN users u ON o.user_id = u.id 
                WHERE o.outlet_id = ? AND o.created_at >= ? AND o.created_at <= ? AND o.status != 'cancelled'
                GROUP BY o.user_id
            ");
            $stmtStaff->execute([$outletId, $strStartUtc, $strEndUtc]);
            $staffStats = $stmtStaff->fetchAll();

            if (empty($staffStats)) {
                $message .= "- No staff sales\n";
            } else {
                foreach ($staffStats as $stat) {
                    $staffName = !empty($stat['full_name']) ? $stat['full_name'] : ($stat['username'] ?? 'Unknown');
                    $message .= "- " . $staffName . ": " . format_currency_custom($stat['revenue'], $settings) . " (" . $stat['order_count'] . " orders)\n";
                }
            }

            // Payment Breakdown
            $message .= "💳 *Payment Breakdown:*
";

            $stmtPayment = $pdo->prepare(" 
                SELECT pt.name, SUM(o.total_amount) as revenue 
                FROM orders o 
                LEFT JOIN payment_types pt ON o.payment_type_id = pt.id 
                WHERE o.outlet_id = ? AND o.created_at >= ? AND o.created_at <= ? AND o.status != 'cancelled'
                GROUP BY o.payment_type_id
            ");
            $stmtPayment->execute([$outletId, $strStartUtc, $strEndUtc]);
            $paymentStats = $stmtPayment->fetchAll();

            if (empty($paymentStats)) {
                $message .= "- No payments\n";
            } else {
                foreach ($paymentStats as $stat) {
                    $paymentName = $stat['name'] ?? 'Unknown';
                    $message .= "- " . $paymentName . ": " . format_currency_custom($stat['revenue'], $settings) . "\n";
                }
            }
        }

        $message .= "--------------------------------\n";
        $message .= "Generated automatically at " . $nowDt->format('H:i:s') . "\n";
        $message .= "Source: " . ($settings['company_name'] ?? 'System') . " Database";

        // --- 4. Send Message ---
        $wablas = new WablasService($pdo);
        $recipients = explode(',', $settings['whatsapp_report_number']);
        $anySuccess = false;

        foreach ($recipients as $recipient) {
            $recipient = trim($recipient);
            if (empty($recipient)) continue;
            
            cron_log("Sending detailed report to: " . $recipient);
            $result = $wablas->sendMessage($recipient, $message);
            
            if (!empty($result['success']) && $result['success'] == true) {
                cron_log("Report sent successfully to " . $recipient);
                $anySuccess = true;
            } else {
                cron_log("Failed to send report to " . $recipient . ": " . ($result['message'] ?? 'Unknown error'));
            }
        }

        if ($anySuccess) {
            file_put_contents($lastReportFile, $todayDisplay);
        }
    }

} catch (Exception $e) {
    cron_log("CRITICAL ERROR: " . $e->getMessage());
}