<?php
if (!defined('ABSPATH')) {
	exit;
}

/**
 * Thin HTTP client for the Tich public API (https://tich.courses/developers).
 * One wp_remote_request per (key, method, path) call, plus a short transient
 * cache for /site and /courses - read-mostly data the product panel and the
 * order-enrichment code both re-read constantly.
 */
class Tich_Api {
	const CACHE_TTL = 5 * MINUTE_IN_SECONDS;

	/**
	 * The key itself says which Tich it belongs to: tich_test_ keys come only
	 * from tich.foo (Tich's own development environment), tich_live_ from
	 * tich.courses - so there's no store-wide environment setting to get
	 * wrong, and a test store can hold keys of both.
	 */
	private static function base_url($key) {
		return Tich_Settings::key_mode($key) === 'test' ? TICH_WC_DEV_API_URL_DEFAULT : TICH_WC_PROD_API_URL;
	}

	/**
	 * @return array{ok:bool,data?:array,code?:string,message?:string,status?:int}
	 */
	private static function request($key, $method, $path, $body = null) {
		$args = [
			'method' => $method,
			'timeout' => 20,
			'sslverify' => true,
			'headers' => [
				'Authorization' => 'Bearer ' . $key,
				'Content-Type' => 'application/json',
				'User-Agent' => 'tich/' . TICH_WC_VERSION,
			],
		];
		if ($body !== null) {
			$args['body'] = wp_json_encode($body);
		}

		$response = wp_remote_request(self::base_url($key) . $path, $args);

		if (is_wp_error($response)) {
			return [
				'ok' => false,
				'code' => 'network_error',
				'message' => $response->get_error_message(),
				'status' => 0,
			];
		}

		$status = wp_remote_retrieve_response_code($response);
		$parsed = json_decode(wp_remote_retrieve_body($response), true);

		if ($status >= 200 && $status < 300) {
			$result = ['ok' => true, 'data' => is_array($parsed) ? $parsed : []];
		} else {
			$code =
				is_array($parsed) && isset($parsed['error']['code']) ? $parsed['error']['code'] : 'unknown_error';
			$message =
				is_array($parsed) && isset($parsed['error']['message'])
					? $parsed['error']['message']
					: sprintf('HTTP %d', $status);
			$result = ['ok' => false, 'code' => $code, 'message' => $message, 'status' => $status];
		}
		// Every response doubles as a free liveness signal for the key - see
		// Tich_Key_Health. Network errors above never reach here: they say
		// nothing about the key.
		Tich_Key_Health::record($key, $result);
		return $result;
	}

	public static function get_site($key, $bypass_cache = false) {
		$cache_key = 'tich_wc_site_' . md5(self::base_url($key) . $key);
		if (!$bypass_cache) {
			$cached = get_transient($cache_key);
			if ($cached !== false) {
				return $cached;
			}
		}
		$result = self::request($key, 'GET', '/site');
		if ($result['ok']) {
			set_transient($cache_key, $result, self::CACHE_TTL);
		}
		return $result;
	}

	public static function get_courses($key, $bypass_cache = false) {
		$cache_key = 'tich_wc_courses_' . md5(self::base_url($key) . $key);
		if (!$bypass_cache) {
			$cached = get_transient($cache_key);
			if ($cached !== false) {
				return $cached;
			}
		}
		$result = self::request($key, 'GET', '/courses');
		if ($result['ok']) {
			set_transient($cache_key, $result, self::CACHE_TTL);
		}
		return $result;
	}

	public static function enroll($key, $email, $course_id, $access_id = null) {
		$body = ['email' => $email, 'courseId' => $course_id];
		if ($access_id) {
			$body['accessId'] = $access_id;
		}
		return self::request($key, 'POST', '/enrollments', $body);
	}

	public static function revoke($key, $email, $course_id) {
		return self::request($key, 'POST', '/enrollments/revoke', ['email' => $email, 'courseId' => $course_id]);
	}

	public static function clear_cache($key) {
		delete_transient('tich_wc_site_' . md5(self::base_url($key) . $key));
		delete_transient('tich_wc_courses_' . md5(self::base_url($key) . $key));
	}
}