<?php

/**
 * Custom Razorpay gateway for Acadlix.
 *
 * IMPORTANT:
 * This is NOT the Razorpay PHP SDK.
 * No third-party Razorpay library is bundled or loaded.
 *
 * @package Acadlix
 */

namespace Yuvayana\Acadlix\Common\Payments\Gateways;

use Yuvayana\Acadlix\Common\Models\Order;

defined('ABSPATH') || exit();

use Yuvayana\Acadlix\Common\Payments\PaymentGatewayInterface;
use WP_REST_Response;
use WP_Error;
use Exception;

// Prevent class re-declaration when another plugin loads a class with the same FQCN.
if (!class_exists(__NAMESPACE__ . '\\Razorpay')) {
  class Razorpay implements PaymentGatewayInterface
  {
    const API_URL = 'https://api.razorpay.com';
    const CONNECTION_TIMEOUT = 30;
    protected bool $is_razorpay_active;
    protected string $razorpay_url;
    protected string $client_id;
    protected string $secret_key;
    protected string $webhook_secret;
    protected float $amount;
    protected string $currency;
    protected array $billing_info;

    public function __construct()
    {
      // Get values from your WP options
      $this->razorpay_url = self::API_URL;
      $this->client_id = acadlix()->helper()->acadlix_get_option('acadlix_razorpay_client_id');
      $this->secret_key = acadlix()->helper()->acadlix_get_option('acadlix_razorpay_secret_key');
      $this->webhook_secret = acadlix()->helper()->acadlix_get_option('acadlix_razorpay_webhook_secret');
      $this->is_razorpay_active = acadlix()->helper()->acadlix_get_option('acadlix_razorpay_active') === 'yes';
    }

    public function is_razorpay_active()
    {
      if ($this->is_razorpay_active && $this->client_id && $this->secret_key && $this->webhook_secret) {
        return true;
      }
      return false;
    }

    public function setAmount(float $amount): self
    {
      $this->amount = $amount;
      return $this;
    }

    public function setCurrency(string $currency): self
    {
      $this->currency = $currency;
      return $this;
    }

    public function setBillingInfo(array $billing_info): self
    {
      $this->billing_info = $billing_info;
      return $this;
    }

    protected function get_request_headers(): array
    {
      return [
        'Authorization' => 'Basic ' . base64_encode($this->client_id . ':' . $this->secret_key),
        'Content-Type' => 'application/json',
      ];
    }

    protected function createConnection($url, $method, $data = [], $retry = 1)
    {
      $args = [
        'method' => $method,
        'headers' => $this->get_request_headers(),
        'timeout' => self::CONNECTION_TIMEOUT,
      ];

      if ($method !== 'GET' && !empty($data)) {
        $args['body'] = wp_json_encode($data);
      }

      $response = wp_remote_request($url, $args);

      if (is_wp_error($response)) {
        throw new Exception(esc_html($response->get_error_message()));
      }

      $result = wp_remote_retrieve_body($response);
      $result = json_decode($result);

      $status_code = wp_remote_retrieve_response_code($response);

      if ($status_code < 200 || $status_code > 299) {
        throw new Exception(esc_html($result?->error?->description ?? 'Something went wrong. Please try again later.'));
      }

      return $result;
    }

    protected function createRazorpayOrder()
    {
      $body = [
        'receipt' => uniqid('order_'),
        'amount' => acadlix()->helper()->acadlix_convert_to_unit_price($this->amount),
        'currency' => $this->currency,
      ];

      $result = $this->createConnection(
        $this->razorpay_url . '/v1/orders',
        'POST',
        $body
      );

      if (isset($result->id)) {
        return $result;
      }
      throw new Exception('Something went wrong. Please try again later.');
    }

    protected function fetchRazorpayPaymentOrder($razorpay_order_id)
    {
      $result = $this->createConnection(
        $this->razorpay_url . '/v1/orders/' . $razorpay_order_id . '/payments',
        'GET'
      );
      return $result;
    }

    protected function captureRazorpayPayment($razorpay_payment_id, $body)
    {
      $result = $this->createConnection(
        $this->razorpay_url . '/v1/payments/' . $razorpay_payment_id . '/capture',
        'POST',
        $body
      );
      return $result;
    }

    protected function fetchRazorpayPayment($razorpay_payment_id)
    {
      $result = $this->createConnection(
        $this->razorpay_url . '/v1/payments/' . $razorpay_payment_id,
        'GET'
      );
      return $result;
    }

    protected function returnUrl($razorpay_order_id)
    {
      $args = [
        'token' => $razorpay_order_id,
        'nonce' => wp_create_nonce('acadlix_payment_nonce'),
      ];
      return add_query_arg($args, esc_url(get_permalink(acadlix()->helper()->acadlix_get_option('acadlix_thankyou_page_id'))));
    }

    protected function cancelUrl($razorpay_order_id)
    {
      $args = [
        'cancelled' => true,
      ];
      return add_query_arg($args, $this->returnUrl($razorpay_order_id));
    }

    protected function getOutputField($razorpay_order_id)
    {
      $box_title = '';
      if (empty($box_title)) {
        $box_title = get_bloginfo('name');
        ;
      }

      if (empty($box_title)) {
        $box_title = 'Pay via Razorpay';
      }
      $return_url = $this->returnUrl($razorpay_order_id);
      $cancel_url = $this->cancelUrl($razorpay_order_id);
      $theme_settings = acadlix()->helper()->acadlix_get_option('acadlix_theme_settings');
      $data = [
        'key' => $this->client_id,
        'order_id' => $razorpay_order_id,
        'amount' => acadlix()->helper()->acadlix_convert_to_unit_price($this->amount),
        'currency' => $this->currency,
        'name' => $box_title,
        'description' => 'Buy now',
        'theme' => [
          'backdrop_color' => 'rgba(0, 0, 0, 0.8)',
        ],
        'callback_url' => $return_url,
        'cancel_url' => $cancel_url,
        'timeout' => 900,
        'config' => [
          'display' => [
            'language' => get_locale(),
          ],
        ],
      ];

      if (isset($theme_settings['palette']['primary']['main']) && !empty($theme_settings['palette']['primary']['main'])) {
        $data['theme']['color'] = $theme_settings['palette']['primary']['main'];
      }

      if (isset($this->billing_info)) {
        $data['prefill']['name'] = $this->billing_info['first_name'] . ' ' . $this->billing_info['last_name'];
        if (!empty($this->billing_info['email'])) {
          $data['prefill']['email'] = $this->billing_info['email'];
        }
        if (!empty($this->billing_info['phone_number']) && !empty($this->billing_info['phonecode'])) {
          $data['prefill']['contact'] = $this->billing_info['phonecode'] . $this->billing_info['phone_number'];
        }
      }

      return $data;
    }


    public function getOrder($razorpay_order_id)
    {
      $order_meta = acadlix()->model()->orderMeta()
        ->where("meta_key", "razorpay_order_id")
        ->where("meta_value", $razorpay_order_id)
        ->first();
      return $order_meta
        ? acadlix()->model()->order()->find($order_meta->order_id)
        : null;
    }

    protected function successOrder($order, $payment_id = '')
    {
      if (!$order) {
        throw new Exception('Order not found');
      }
      $order->updateOrCreateMeta('razorpay_payment_id', $payment_id);
      $message = "Razorpay PaymentId: {$payment_id}";
      $order->createActivityLog($message);

      $order->success_order();
      $message = "Order status updated to success";
      $order->createActivityLog($message);

      if ($order->order_items()->count() > 0) {
        foreach ($order->order_items as $item) {
          $cart = acadlix()->model()->courseCart()
            ->where("user_id", $order->user_id)
            ->where("item_id", $item->item_id)
            ->where("type", $item->type)
            ->first();
          if ($cart) {
            $cart->delete();
          }
        }
      }
      return ['success' => true, 'message' => 'Order captured successfully'];
    }

    public function failedOrder($order, $message = ''): array
    {
      if (!$order) {
        throw new Exception('Order not found');
      }
      $order->failed_order();
      $message = "Order status updated to failed";
      $order->createActivityLog($message);

      $order->updateOrCreateMeta('failure_reason', $message);
      return ['success' => true, 'message' => $message];
    }

    public function processOrder(): array|object|null
    {
      if (!$this->is_razorpay_active()) {
        throw new Exception('Razorpay not active');
      }
      $result = $this->createRazorpayOrder();
      if ($result) {
        return $this->getOutputField($result->id);
      }
      throw new Exception('Something went wrong. Please try again later.');
    }

    public function verifyWebhook(array $data): WP_REST_Response|WP_Error
    {
      try {
        if (!$this->is_razorpay_active()) {
          throw new Exception('Razorpay not active');
        }

        if (empty($this->webhook_secret)) {
          throw new Exception('Razorpay webhook secret missing');
        }
        $payload = $data['stream'] ?? '';
        $signature = $data['headers']['razorpay_signature'] ?? '';


        if (!$payload || !$signature) {
          throw new Exception('Razorpay webhook verification failed: Missing payload or signature.');
        }

        $expected_signature = hash_hmac('sha256', $payload, $this->webhook_secret);


        if (!hash_equals($expected_signature, $signature)) {
          return new WP_Error('invalid_signature', 'Signature verification failed', ['status' => 403]);
        }


        $event = json_decode($payload);
        switch ($event->event) {
          case 'payment.authorized':
          case 'payment.failed':
            $razorpay_order_id = $event->payload->payment->entity->order_id;
            $response = $this->orderCapture($razorpay_order_id);
            $response = new WP_REST_Response($response, 200);
            break;
          default:
            $response = new WP_REST_Response(['message' => 'Event ignored'], 200);
            break;
        }
        return $response;
      } catch (Exception $e) {
        return new WP_Error(
          'webhook_error',
          __('Razorpay webhook error: ', 'acadlix') . esc_html($e->getMessage()),
          ['status' => 500]
        );
      }
    }

    protected function orderCapture($razorpay_order_id)
    {
      try {
        if (empty($razorpay_order_id)) {
          throw new Exception('Razorpay order id not found');
        }

        $order = $this->getOrder($razorpay_order_id);
        if (!$order) {
          throw new Exception('Order not found');
        }

        if ($order->status == Order::STATUS_SUCCESS) {
          return ['success' => true, 'message' => 'Order already processed'];
        }

        $razorpay_payments = $this->fetchRazorpayPaymentOrder($razorpay_order_id);
        if (empty($razorpay_payments->count)) {
          return $this->failedOrder($order, 'Order not captured');
        }
        $razorpay_payment = $razorpay_payments->items[0];

        // If order is paid, get the payment which is authorized/captured/refunded.
        foreach ($razorpay_payments->items as $razorpay_payment_item) {
          if ('created' !== $razorpay_payment_item->status && 'failed' !== $razorpay_payment_item->status) {
            $razorpay_payment = $razorpay_payment_item;
          }
        }

        if (!empty($razorpay_payment->error_description)) {
          return $this->failedOrder($order, $razorpay_payment->error_description);
        }

        if ($razorpay_payment->status == 'authorized') {
          $this->captureRazorpayPayment(
            $razorpay_payment->id,
            [
              'amount' => $razorpay_payment->amount,
              'currency' => $razorpay_payment->currency,
            ]
          );
        }

        $razorpay_payment = $this->fetchRazorpayPayment($razorpay_payment->id);

        if ($razorpay_payment->status == 'captured') {
          return $this->successOrder($order, $razorpay_payment->id);
        }

        return ['success' => false, 'message' => 'Order not captured'];
      } catch (Exception $e) {
        throw new Exception(esc_html($e->getMessage()));
      }
    }

    public function verifyOrder($razorpay_order_id): void
    {
      try {
        if (!$this->is_razorpay_active()) {
          throw new Exception('Razorpay not active');
        }

        if (!$razorpay_order_id) {
          throw new Exception('Razorpay order id not found');
        }

        $this->orderCapture($razorpay_order_id);
      } catch (Exception $e) {
        return;
      }
    }

  }
} // End of class_exists check