<?php

declare(strict_types=1);

namespace App\Services;

use Core\Database;
use PDO;

class SuperQiParserService
{
    /**
     * Ingests and processes a notification or parsed receipt from the Android listener bridge.
     */
    public static function processIngestedNotification(array $data): array
    {
        $refNumber = trim((string)($data['reference_number'] ?? ''));
        $amount = (float)($data['amount'] ?? 0);
        $sender = trim((string)($data['sender'] ?? ''));
        $recipient = trim((string)($data['recipient'] ?? ''));
        $rawText = (string)($data['raw_text'] ?? '');

        if (empty($refNumber) || $amount <= 0) {
            return [
                'success' => false,
                'message' => 'Invalid transaction reference or amount.',
            ];
        }

        $pdo = Database::getConnection();

        // 1. Check if transaction has already been recorded and verified
        $stmt = $pdo->prepare('SELECT id, status FROM transactions WHERE reference_number = :ref LIMIT 1');
        $stmt->execute([':ref' => $refNumber]);
        $existing = $stmt->fetch(PDO::FETCH_ASSOC);

        if ($existing && $existing['status'] === 'VERIFIED_AUTO') {
            return [
                'success' => true,
                'message' => 'Transaction already processed and verified previously.',
                'transaction_id' => $existing['id'],
            ];
        }

        // 2. Search for a pending subscription matching this reference or pending payment
        // First, check if any user submitted this reference number
        $stmt = $pdo->prepare('
            SELECT t.id AS trans_id, t.subscription_id, s.user_id, s.plan_name, u.phone, u.full_name
            FROM transactions t
            JOIN subscriptions s ON s.id = t.subscription_id
            JOIN users u ON u.id = s.user_id
            WHERE t.reference_number = :ref AND t.status = "SUBMITTED"
            LIMIT 1
        ');
        $stmt->execute([':ref' => $refNumber]);
        $matched = $stmt->fetch(PDO::FETCH_ASSOC);

        if ($matched) {
            $pdo->beginTransaction();
            try {
                // Update transaction
                $updTrans = $pdo->prepare('
                    UPDATE transactions 
                    SET status = "VERIFIED_AUTO", amount = :amount, verified_at = NOW(),
                        raw_webhook_payload = :raw
                    WHERE id = :id
                ');
                $updTrans->execute([
                    ':amount' => $amount,
                    ':raw' => json_encode($data, JSON_UNESCAPED_UNICODE),
                    ':id' => $matched['trans_id'],
                ]);

                // Activate subscription
                $updSub = $pdo->prepare('
                    UPDATE subscriptions 
                    SET status = "ACTIVE", starts_at = CURDATE(), expires_at = DATE_ADD(CURDATE(), INTERVAL 2 YEAR)
                    WHERE id = :sub_id
                ');
                $updSub->execute([':sub_id' => $matched['subscription_id']]);

                // Ensure user status is active
                $updUser = $pdo->prepare('UPDATE users SET status = "ACTIVE" WHERE id = :user_id');
                $updUser->execute([':user_id' => $matched['user_id']]);

                $pdo->commit();

                return [
                    'success' => true,
                    'matched' => true,
                    'message' => 'Subscription activated automatically for ' . $matched['full_name'],
                    'user_id' => $matched['user_id'],
                    'phone' => $matched['phone'],
                ];
            } catch (\Throwable $e) {
                $pdo->rollBack();
                return ['success' => false, 'error' => $e->getMessage()];
            }
        }

        // If no user has claimed it yet, record it in transactions as unassigned credit
        $insStmt = $pdo->prepare('
            INSERT INTO transactions (subscription_id, user_id, method, reference_number, sender_account_or_phone, recipient_account, amount, currency, status, raw_webhook_payload, verified_at)
            VALUES (0, 0, "SUPER_QI", :ref, :sender, :recipient, :amount, "IQD", "VERIFIED_AUTO", :raw, NOW())
            ON DUPLICATE KEY UPDATE amount = VALUES(amount), raw_webhook_payload = VALUES(raw_webhook_payload)
        ');
        $insStmt->execute([
            ':ref' => $refNumber,
            ':sender' => $sender,
            ':recipient' => $recipient,
            ':amount' => $amount,
            ':raw' => json_encode($data, JSON_UNESCAPED_UNICODE),
        ]);

        return [
            'success' => true,
            'matched' => false,
            'message' => 'Transaction recorded. Awaiting user claim in app.',
            'reference_number' => $refNumber,
        ];
    }
}