<?php
/**
 * Nabeh Payment Verification Endpoint
 *
 * Auto-detects the user's pending invoice and uses Gemini AI to verify
 * the receipt image against the invoice. No manual invoice number needed.
 *
 * ===============================
 * INPUT (JSON body)
 * ===============================
 * driver_id (optional) — from Nabeh's Siro API resolution (preferred)
 * phone (required if no driver_id) — lookup via Siro backend resolve_user
 * payment_method (required) — shamcash / cliq / mtn / sms
 * receipt_image (optional for AI verification)
 * image_mime_type (optional, default: image/jpeg)
 *
 * ===============================
 * FLOW
 * ===============================
 *  1. Auth via jwtconnect.php (X-API-Key → NABEH_API_KEY)
 *  2. Resolve driverID:
 *     a. Use driver_id directly if provided
 *     b. Otherwise call Siro backend resolve_user.php (phone → driverID)
 *  3. Auto-find latest pending invoice for that driver
 *  4. If shamcash + receipt_image:
 *     a. Call GeminiAi::verifyPayment(invoice_number, amount, "ShamCash", "", receipt_image)
 *     b. Gemini returns {"verified": true/false, "reason": "..."}
 *     c. If verified → UPDATE status='processing' → finalizeShamCashDeposit()
 *     d. Return result
 *  5. If other methods or no receipt_image:
 *     - Return invoice status info
 *
 * Auth: X-API-Key header → NABEH_API_KEY (via jwtconnect.php Path 5)
 */

require_once __DIR__ . '/../../jwtconnect.php';
require_once __DIR__ . '/../GeminiAi.php';

if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
    http_response_code(405);
    echo json_encode(['status' => 'failure', 'message' => 'Method not allowed']);
    exit;
}

$raw = file_get_contents('php://input');
$data = json_decode($raw, true) ?: $_POST;

$driverId = trim($data['driver_id'] ?? '');
$phone = trim($data['phone'] ?? '');
$paymentMethod = strtolower(trim($data['payment_method'] ?? ''));
$receiptImage = $data['receipt_image'] ?? '';
$imageMimeType = $data['image_mime_type'] ?? 'image/jpeg';

// ── Step 1: Resolve driverID ──────────────────────────────────
// driver_id (from Nabeh's Siro API resolution) is preferred
// phone fallback calls Siro backend resolve_user endpoint via S2S
$userName  = '';
$userPhone = $phone;
$userType  = 'driver';

if (empty($driverId) && empty($phone)) {
    printFailure('driver_id or phone is required');
    exit;
}

if (empty($driverId) && !empty($phone)) {
    $siroBackendUrl = rtrim(getenv('SIRO_BACKEND_URL') ?: 'https://api-syria.siromove.com/siro', '/');
    $resolveUrl = $siroBackendUrl . '/nabeh/resolve_user.php';

    $resolvePayload = json_encode(['phone' => $phone]);
    $apiKey = getenv('NABEH_API_KEY') ?: '';

    $ch = curl_init($resolveUrl);
    curl_setopt_array($ch, [
        CURLOPT_RETURNTRANSFER => true,
        CURLOPT_POST           => true,
        CURLOPT_POSTFIELDS     => $resolvePayload,
        CURLOPT_HTTPHEADER     => [
            'Content-Type: application/json',
            'X-API-Key: ' . $apiKey,
        ],
        CURLOPT_TIMEOUT        => 10,
    ]);
    $resolveRes = curl_exec($ch);
    $httpCode   = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    curl_close($ch);

    if ($httpCode !== 200 || empty($resolveRes)) {
        printFailure('Could not resolve user. Please ensure you are registered in Siro.');
        exit;
    }

    $resolveData = json_decode($resolveRes, true);
    if (($resolveData['status'] ?? '') !== 'success' || empty($resolveData['data']['user_id'] ?? '')) {
        printFailure('User not found in Siro system.');
        exit;
    }

    $driverId = $resolveData['data']['user_id'];
    $userName = $resolveData['data']['name'] ?? '';
    $userPhone = $resolveData['data']['phone'] ?? $phone;
    $userType = $resolveData['data']['type'] ?? 'driver';
}

$paymentMethod = $paymentMethod ?: 'shamcash';

// ═══════════════════════════════════════════════════════════════
// SHAMCASH — AI Verification (auto-find pending invoice)
// ═══════════════════════════════════════════════════════════════
if ($paymentMethod === 'shamcash') {
    // Auto-find latest pending invoice for this driver
    $stmt = $con->prepare("
        SELECT id, invoice_number, amount, status, created_at
        FROM invoices_shamcash
        WHERE driverID = ? AND status = 'pending'
        ORDER BY created_at DESC
        LIMIT 1
    ");
    $stmt->execute([$driverId]);
    $invoice = $stmt->fetch();

    if (!$invoice) {
        $stmt = $con->prepare("
            SELECT id, invoice_number, amount, status, created_at
            FROM invoices_shamcash
            WHERE driverID = ? AND status = 'completed'
            ORDER BY created_at DESC
            LIMIT 1
        ");
        $stmt->execute([$driverId]);
        $lastCompleted = $stmt->fetch();

        if ($lastCompleted) {
            echo json_encode([
                'status'  => 'success',
                'verified'=> true,
                'message' => 'آخر فاتورة لديك مكتملة بالفعل.',
                'invoice' => $lastCompleted,
            ], JSON_UNESCAPED_UNICODE);
            exit;
        }

        echo json_encode([
            'status'  => 'success',
            'verified'=> false,
            'message' => 'لا توجد فاتورة معلقة. يرجى إنشاء فاتورة عبر تطبيق Siro أولاً.',
        ], JSON_UNESCAPED_UNICODE);
        exit;
    }

    // ── If no receipt image, just return invoice info ─────
    if (empty($receiptImage)) {
        echo json_encode([
            'status'         => 'success',
            'verified'       => false,
            'requires_image' => true,
            'message'        => "تم العثور على فاتورة رقم {$invoice['invoice_number']} بمبلغ {$invoice['amount']} ل.س. يرجى إرسال صورة الإيصال.",
            'invoice'        => $invoice,
        ], JSON_UNESCAPED_UNICODE);
        exit;
    }

    // ── Run AI verification ─────────────────────────────────
    $geminiKey = getenv('GEMINI_API_KEY');
    if (empty($geminiKey)) {
        printFailure('AI verification service not configured');
        exit;
    }

    try {
        $gemini = new GeminiAi($geminiKey);
        $aiResult = $gemini->verifyPayment(
            $invoice['invoice_number'],
            $invoice['amount'],
            'ShamCash',
            '',
            $receiptImage
        );

        if (!empty($aiResult['verified'])) {
            // ── AI confirmed → finalize ─────────────────────
            $con->beginTransaction();

            $upd = $con->prepare("
                UPDATE invoices_shamcash
                SET status = 'processing'
                WHERE id = ? AND status = 'pending'
            ");
            $upd->execute([$invoice['id']]);

            if ($upd->rowCount() > 0) {
                require_once __DIR__ . '/../shamcash/finalize_deposit.php';

                $finalized = finalizeShamCashDeposit($con, $invoice['id']);

                if ($finalized) {
                    $con->commit();
                    echo json_encode([
                        'status'   => 'success',
                        'verified' => true,
                        'message'  => '✅ تم التحقق من عملية الدفع بنجاح! تم تحديث رصيد حسابك.',
                        'invoice'  => [
                            'invoice_number' => $invoice['invoice_number'],
                            'amount'         => $invoice['amount'],
                            'status'         => 'completed',
                        ],
                        'ai_reason' => $aiResult['reason'] ?? null,
                    ], JSON_UNESCAPED_UNICODE);
                } else {
                    $con->rollBack();
                    echo json_encode([
                        'status'  => 'error',
                        'message' => 'Verification passed but wallet update failed. Contact support.',
                    ], JSON_UNESCAPED_UNICODE);
                }
            } else {
                $con->rollBack();
                echo json_encode([
                    'status'  => 'success',
                    'verified'=> false,
                    'message' => 'These funds have already been credited.',
                ], JSON_UNESCAPED_UNICODE);
            }
        } else {
            $reason = $aiResult['reason'] ?? 'لم يتم التأكيد';
            echo json_encode([
                'status'    => 'success',
                'verified'  => false,
                'message'   => "⚠️ $reason",
                'ai_reason' => $reason,
            ], JSON_UNESCAPED_UNICODE);
        }
    } catch (Exception $e) {
        error_log("[Nabeh ShamCash AI] " . $e->getMessage());
        printFailure('AI verification service error');
    }
    exit;
}

// ═══════════════════════════════════════════════════════════════
// OTHER METHODS — Status query (find pending invoice by phone)
// ═══════════════════════════════════════════════════════════════
$table = '';
$columns = '';
$conditions = '';

switch ($paymentMethod) {
    case 'sms':
    case 'syriatel':
        $table      = 'invoices_sms';
        $columns    = "id, invoice_number, amount, status, NULL AS transaction_id, created_at, paid_at";
        $conditions = "driverID = ? AND status = 'pending'";
        break;

    case 'cliq':
        $table      = 'cliq_invoices';
        $columns    = "id, invoice_number, amount, status, NULL AS transaction_id, created_at, updated_at AS paid_at";
        $conditions = "user_id = ? AND user_type = 'driver' AND status = 'pending'";
        break;

    case 'mtn':
        $table      = 'mtn_invoices';
        $columns    = "id, invoice_number, amount, status, mtn_transaction_id AS transaction_id, created_at, updated_at AS paid_at";
        $conditions = "user_id = ? AND user_type = 'driver' AND status = 'pending'";
        break;

    default:
        printFailure("Invalid payment method: $paymentMethod");
        exit;
}

$stmt = $con->prepare("
    SELECT $columns, ? AS payment_method
    FROM $table
    WHERE $conditions
    ORDER BY created_at DESC
    LIMIT 5
");
$stmt->execute([$paymentMethod, $driverId]);
$invoices = $stmt->fetchAll();

echo json_encode([
    'status'   => 'success',
    'verified' => !empty($invoices),
    'message'  => empty($invoices) ? 'لا توجد فواتير معلقة.' : null,
    'user'     => [
        'id'    => $driverId,
        'phone' => $userPhone,
        'name'  => $userName,
    ],
    'invoices' => $invoices,
], JSON_UNESCAPED_UNICODE);