<?php
require_once __DIR__ . '/../../connect.php'; // Provides $con, $redisLocation, $encryptionHelper, jsonSuccess/jsonError

// getSpeed.php (Redis-Optimized Version)
try {
    // 1) قراءة والتحقق من الإحداثيات
    $southwestLat = filterRequest("southwestLat");
    $southwestLon = filterRequest("southwestLon");
    $northeastLat = filterRequest("northeastLat");
    $northeastLon = filterRequest("northeastLon");

    if ($southwestLat === false || $southwestLon === false || $northeastLat === false || $northeastLon === false) {
        jsonError("Invalid coordinates provided");
        exit;
    }

    // =================================================================
    // الخطوة 1: البحث في Redis باستخدام تقنية GeoRadius (أسرع 100 مرة من MySQL)
    // =================================================================
    $centerLat = ($southwestLat + $northeastLat) / 2.0;
    $centerLon = ($southwestLon + $northeastLon) / 2.0;

    // حساب تقريبي لنصف القطر بالكيلومترات بناءً على الصندوق (Bounding Box)
    $earth_radius = 6371;
    $dLat = deg2rad($southwestLat - $centerLat);
    $dLon = deg2rad($southwestLon - $centerLon);
    $a = sin($dLat/2) * sin($dLat/2) + cos(deg2rad($centerLat)) * cos(deg2rad($southwestLat)) * sin($dLon/2) * sin($dLon/2);
    $c = 2 * asin(sqrt($a));
    $radiusKm = max(1, ($earth_radius * $c) + 1);

    // سحب معرفات السائقين المتاحين حول الراكب من سيرفر المواقع (Dual Redis)
    $driver_ids = [];
    if (isset($redisLocation)) {
        $redisResults = $redisLocation->geoRadius('geo:drivers:available', $centerLon, $centerLat, $radiusKm, 'km');
        if ($redisResults) {
            foreach ($redisResults as $res) {
                // قد يرجع Redis مصفوفة داخلية إذا تم تمرير خيارات، ولكن بالوضع الافتراضي يرجع سلاسل نصية
                $driver_ids[] = is_array($res) ? $res[0] : $res;
            }
        }
    }

    if (empty($driver_ids)) {
        jsonError("No car locations found in the specified area.");
        exit;
    }

    // =================================================================
    // الخطوة 2: جلب تفاصيل الموقع الدقيقة والسرعة لكل سائق من Redis Pipeline
    // =================================================================
    $pipe = $redisLocation->pipeline();
    foreach ($driver_ids as $id) {
        $pipe->hGetAll("driver:profile:$id");
    }
    $profiles = $pipe->exec();

    $locations = [];
    foreach ($driver_ids as $index => $id) {
        $profile = $profiles[$index];
        if (!$profile || empty($profile['lat'])) continue;

        // تجاهل المواقع القديمة (أكثر من 3 دقائق)
        $updatedAt = $profile['updated_at'] ?? 0;
        if (time() - $updatedAt > 180) continue;

        $locations[] = [
            'driver_id' => $id,
            'latitude' => $profile['lat'],
            'longitude' => $profile['lng'],
            'heading' => $profile['heading'] ?? 0,
            'speed' => $profile['speed'] ?? 0,
            'status' => 'off', // متواجدون في geo:drivers:available
            'updated_at' => date('Y-m-d H:i:s', $updatedAt)
        ];
    }

    if (empty($locations)) {
        jsonError("No fresh car locations found in the specified area.");
        exit;
    }

    // =================================================================
    // الخطوة 3: جلب البيانات الثابتة (السيارة، الموديل، التقييم) من MySQL
    // =================================================================
    $drivers_info = [];
    $valid_driver_ids = array_column($locations, 'driver_id');
    $placeholders = implode(',', array_fill(0, count($valid_driver_ids), '?'));

    $sql_drivers_info = "
        SELECT
            d.id AS driver_id, d.phone, d.email, d.birthdate, d.first_name, d.last_name, d.gender, d.maritalStatus,
            cr.make, cr.model, cr.color, cr.color_hex, cr.year,
            dt.token,
            COALESCE(rdAvg.ratingDriver, 0) AS ratingDriver,
            COALESCE(rdAvg.ratingCount, 0) AS ratingCount
        FROM driver d
        LEFT JOIN CarRegistration cr ON cr.driverID = d.id
        LEFT JOIN driverToken dt ON dt.captain_id = d.id
        LEFT JOIN (
            SELECT driver_id, AVG(rating) AS ratingDriver, COUNT(id) AS ratingCount
            FROM ratingDriver
            GROUP BY driver_id
        ) rdAvg ON rdAvg.driver_id = d.id
        WHERE d.id IN ($placeholders)
          AND (cr.model NOT LIKE '%Van%' AND cr.make NOT LIKE '%Van%')
    ";

    $stmt_drivers_info = $con->prepare($sql_drivers_info);
    $stmt_drivers_info->execute($valid_driver_ids);
    $drivers_info_raw = $stmt_drivers_info->fetchAll(PDO::FETCH_ASSOC);

    foreach ($drivers_info_raw as $driver) {
        $drivers_info[$driver['driver_id']] = $driver;
    }

    // =================================================================
    // الخطوة 4: دمج النتائج والترتيب 
    // =================================================================
    $final_results = [];
    foreach ($locations as $location) {
        $driver_id = $location['driver_id'];
        if (isset($drivers_info[$driver_id])) {
            $final_results[] = array_merge($location, $drivers_info[$driver_id]);
        }
    }

    usort($final_results, function ($a, $b) {
        if ($a['ratingDriver'] != $b['ratingDriver']) {
            return $b['ratingDriver'] <=> $a['ratingDriver'];
        }
        if ($a['ratingCount'] != $b['ratingCount']) {
            return $b['ratingCount'] <=> $a['ratingCount'];
        }
        return strtotime($b['updated_at']) <=> strtotime($a['updated_at']);
    });

    $limited_results = array_slice($final_results, 0, 10);

    if (empty($limited_results)) {
        jsonError("No cars matching the specific criteria found.");
        exit;
    }

    // =================================================================
    // الخطوة 5: فك التشفير وحساب العمر
    // =================================================================
    $fieldsToDecrypt = ['phone','email','gender','birthdate', 'first_name','last_name', 'token','car_plate','vin'];
    foreach ($limited_results as &$row) {
        foreach ($fieldsToDecrypt as $field) {
            if (isset($row[$field]) && !empty($row[$field])) {
                try { $row[$field] = $encryptionHelper->decryptData($row[$field]); }
                catch (Exception $e) { $row[$field] = null; }
            }
        }
        if (!empty($row['birthdate'])) {
            try {
                $birthDate = new DateTime($row['birthdate']);
                $today = new DateTime();
                $row['age'] = $today->diff($birthDate)->y;
            } catch (Exception $e) { $row['age'] = null; }
        } else {
            $row['age'] = null;
        }
    }
    unset($row);

    jsonSuccess($limited_results);

} catch (PDOException $e) {
    error_log("[getSpeed.php PDO] " . $e->getMessage());
    jsonError("An internal error occurred. Please try again later.");
} catch (Throwable $e) {
    error_log("[getSpeed.php] " . $e->getMessage());
    jsonError("An internal error occurred. Please try again later.");
}