<?php
namespace Opencart\Catalog\Controller\Extension\Hutko\Payment;

class Hutko extends \Opencart\System\Engine\Controller {
	private $checkout_url = 'https://pay.hutko.org/api/checkout/url/';

	public function index(): string {
		$this->load->language('extension/hutko/payment/hutko');
		return $this->load->view('extension/hutko/payment/hutko', ['language' => $this->config->get('config_language')]);
	}

	public function confirm(): void {
		$this->load->language('extension/hutko/payment/hutko');
		$this->load->model('checkout/order');
		
		$json = [];

		if (!isset($this->session->data['order_id'])) {
			$json['error'] = 'Session missing';
			$json['redirect'] = $this->url->link('checkout/failure', 'language=' . $this->config->get('config_language'), true);
		} else {
			$order_info = $this->model_checkout_order->getOrder($this->session->data['order_id']);
			
			if (!$order_info) {
				$json['error'] = 'Order missing';
			} else {
				$hutko_ref = $order_info['order_id'] . '#' . time();

				// Call the shared logic method
				$request_data = $this->buildRequest($order_info, $hutko_ref);
				
				if (!$request_data) {
					$json['error'] = $this->language->get('error_payment_data_build');
				} else {
					$this->load->model('extension/hutko/payment/hutko');
					$response = $this->api($this->checkout_url, $request_data);

					if (($response['response']['response_status'] ?? '') === 'success' && !empty($response['response']['checkout_url'])) {
						$url = $response['response']['checkout_url'];

						$this->model_extension_hutko_payment_hutko->logTransaction(
							$order_info['order_id'],
							$hutko_ref,
							'payment_request',
							'created',
							$request_data['amount'] / 100,
							$request_data['currency'],
							[
								'request_data' => $request_data,
								'checkout_url' => $url,
								'user_agent'   => $this->request->server['HTTP_USER_AGENT'] ?? ''
							]
						);

						if ($order_info['order_status_id'] == 0) {
							$this->model_checkout_order->addHistory($order_info['order_id'], $this->config->get('payment_hutko_new_order_status_id'), $this->language->get('text_initiated_payment'), false);
						}
						
						$json['redirect'] = $url;
					} else {
						$err = $response['response']['error_message'] ?? $this->language->get('error_api_communication');
						$json['error'] = $err;
						$this->model_extension_hutko_payment_hutko->logTransaction(
							$order_info['order_id'],
							$hutko_ref,
							'payment_request',
							'failed',
							$request_data['amount'] / 100,
							$request_data['currency'],
							['error' => $err, 'api_response' => $response]
						);
					}
				}
			}
		}

		$this->response->addHeader('Content-Type: application/json');
		$this->response->setOutput(json_encode($json));
	}

	public function callback(): void {
		$this->load->language('extension/hutko/payment/hutko');
		
		$input = file_get_contents("php://input");
		$data = json_decode($input, true);

		// Basic Validation
		if (!$data || !isset($data['order_id'])) {
			http_response_code(400);
			exit('Invalid Request');
		}

		// Verify Signature first
		if (!$this->validate($data)) {
			http_response_code(400);
			exit('Invalid Signature');
		}

		$hutko_ref = $data['order_id']; // e.g., 55#17555555
		$parts = explode('#', $hutko_ref);
		$order_id = (int)$parts[0];
		
		$this->load->model('checkout/order');
		$order_info = $this->model_checkout_order->getOrder($order_id);

		if ($order_info) {
			$this->load->model('extension/hutko/payment/hutko');
			$status = $data['order_status'] ?? '';

			// 1. Log the RAW callback to our internal table
			$this->model_extension_hutko_payment_hutko->logTransaction(
				$order_id,
				$hutko_ref,
				'callback',
				($status === 'approved') ? 'success' : 'failed',
				isset($data['amount']) ? $data['amount'] / 100 : 0,
				$data['currency'] ?? '',
				$data // Save full payload
			);

			$current_status_id = (int)$order_info['order_status_id'];
			
			// 2. Update OpenCart History (Clean Messages Only)
			if ($status === 'approved') {
				if (isset($data['response_status']) && $data['response_status'] == 'success') {
					$target_status_id = (int)$this->config->get('payment_hutko_success_status_id');
					
					// Avoid duplicates: Only update if status is different
					if ($current_status_id != $target_status_id) {
						$this->model_checkout_order->addHistory($order_id, $target_status_id, $this->language->get('text_payment_approved'), true);
					}
					echo "OK";
				} else {
					echo "Approved but invalid details";
				}
			} elseif ($status === 'declined') {
				$target_status_id = (int)$this->config->get('payment_hutko_declined_status_id');
				if ($current_status_id != $target_status_id) {
					// Don't notify customer on decline to avoid spam if they retry
					$this->model_checkout_order->addHistory($order_id, $target_status_id, $this->language->get('text_payment_declined'), false);
				}
				echo "Order declined";
			} elseif ($status === 'expired') {
				// Often better not to change order status to "Expired" if you want to allow retries, 
				// but if you do, don't notify customer.
				$target_status_id = (int)$this->config->get('payment_hutko_expired_status_id');
				if ($current_status_id != $target_status_id) {
					$this->model_checkout_order->addHistory($order_id, $target_status_id, $this->language->get('text_payment_expired'), false);
				}
				echo "Order expired";
			} else {
				echo "Status received";
			}
		} else {
			http_response_code(404);
			echo "Order not found";
		}
	}

	
	private function validate($data) {
		$sig = $data['signature'] ?? '';
		unset($data['signature'], $data['response_signature_string']);
		return hash_equals($this->sign($data), $sig);
	}


	// =========================================================================
	// SHARED LOGIC START
	// MAINTENANCE WARNING: Keep synchronized with Admin Controller
	// =========================================================================

	private function buildRequest($order, $hutko_ref) {
		$products_data = $this->getProducts($order['order_id'], $order);
		
		$total_products_sum = 0;
		foreach ($products_data as $p) {
			$total_products_sum += $p['total_amount'];
		}

		$totals_query = $this->db->query("SELECT * FROM " . DB_PREFIX . "order_total WHERE order_id = '" . (int)$order['order_id'] . "' ORDER BY sort_order ASC");
		$shipping_cost = 0;
		foreach ($totals_query->rows as $t) {
			if ($t['code'] == 'shipping') {
				$shipping_cost += $this->currency->format($t['value'], $order['currency_code'], $order['currency_value'], false);
			}
		}

		$order_total_val = $this->currency->format($order['total'], $order['currency_code'], $order['currency_value'], false);
		
		if ($this->config->get('payment_hutko_include_discount_to_total')) {
			$amount_val = $order_total_val;
			if (!$this->config->get('payment_hutko_shipping_include')) {
				$amount_val -= $shipping_cost;
			}
		} else {
			$amount_val = $total_products_sum;
		}

		if ($amount_val < 0.01) $amount_val = 0.01;
		$total_cents = (int)round($amount_val * 100);

		// Catalog side URLs are simple
		$response_url = $this->url->link('checkout/success', 'language=' . $this->config->get('config_language'), true);
		$callback_url = $this->url->link('extension/hutko/payment/hutko.callback', '', true);

		$reservation_data = [
			"cms_name"         => "OpenCart",
			"cms_version"      => VERSION,
			"shop_domain"      => preg_replace("(^https?://)", "", HTTP_SERVER),
			"phonemobile"      => $order['telephone'],
			"customer_address" => $order['payment_address_1'] . ' ' . $order['payment_address_2'],
			"customer_country" => $order['shipping_iso_code_2'],
			"customer_name"    => $order['firstname'] . ' ' . $order['lastname'],
			"customer_email"   => $order['email'],
			"products"         => $products_data
		];

		$data = [
			'order_id'            => $hutko_ref,
			'merchant_id'         => $this->config->get('payment_hutko_merchant_id'),
			'amount'              => $total_cents,
			'currency'            => $order['currency_code'],
			'order_desc'          => 'Order #' . $order['order_id'],
			'response_url'        => $response_url,
			'server_callback_url' => $callback_url,
			'sender_email'        => $order['email'],
			'reservation_data'    => base64_encode(json_encode($reservation_data))
		];
		
		$data['signature'] = $this->sign($data);
		return $data;
	}

	private function getProducts(int $order_id, array $order_info): array {
		$products_data = [];
		$query = $this->db->query("SELECT * FROM `" . DB_PREFIX . "order_product` WHERE `order_id` = '" . (int)$order_id . "'");

		foreach ($query->rows as $product) {
			$unit_price = $this->currency->format($product['price'] + $product['tax'], $order_info['currency_code'], $order_info['currency_value'], false);
			$total_price = $this->currency->format($product['total'] + ($product['tax'] * $product['quantity']), $order_info['currency_code'], $order_info['currency_value'], false);

			$products_data[] = [
				"id"           => $product['product_id'],
				"name"         => $product['name'] . ' ' . $product['model'],
				"price"        => round((float)$unit_price, 2),
				"total_amount" => round((float)$total_price, 2),
				"quantity"     => (int)$product['quantity'],
			];
		}

		if ($this->config->get('payment_hutko_shipping_include')) {
			$totals = $this->db->query("SELECT * FROM " . DB_PREFIX . "order_total WHERE order_id = '" . (int)$order_id . "' AND code = 'shipping'");
			if ($totals->num_rows) {
				$shipping_val = $this->currency->format($totals->row['value'], $order_info['currency_code'], $order_info['currency_value'], false);
				if ($shipping_val > 0) {
					$products_data[] = [
						"id"           => $this->config->get('payment_hutko_shipping_product_code') ?: 'SHIPPING',
						"name"         => $this->config->get('payment_hutko_shipping_product_name') ?: 'Shipping',
						"price"        => round((float)$shipping_val, 2),
						"total_amount" => round((float)$shipping_val, 2),
						"quantity"     => 1,
					];
				}
			}
		}
		return $products_data;
	}

	private function sign($data) {
		$key = $this->config->get('payment_hutko_secret_key');
		$arr = array_filter($data, function($v){ return $v !== '' && $v !== null; });
		ksort($arr);
		$str = $key;
		foreach($arr as $v) $str .= '|' . $v;
		return sha1($str);
	}

	private function api($url, $data) {
		if ($this->config->get('payment_hutko_save_logs')) $this->logOC('Req: ' . json_encode($data));

		$ch = curl_init($url);
		curl_setopt($ch, CURLOPT_POST, 1);
		curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode(['request' => $data]));
		curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
		curl_setopt($ch, CURLOPT_HTTPHEADER, ['Content-Type: application/json']);
		curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, true);
		curl_setopt($ch, CURLOPT_TIMEOUT, 30);
		
		$res = curl_exec($ch);
		$error = curl_error($ch);
		curl_close($ch);

		if ($this->config->get('payment_hutko_save_logs')) {
			$this->logOC('Res: ' . $res);
			if ($error) $this->logOC('Curl Error: ' . $error);
		}
		
		return json_decode($res, true) ?: [];
	}

	private function logOC($msg) {
		$this->log->write("Hutko Payment: " . $msg);
	}
	// =========================================================================
	// SHARED LOGIC END
	// =========================================================================
}