<?php
namespace ChargeForms\Includes;
if ( ! defined( 'ABSPATH' ) ) { exit; }

/** Transport success and a paid, site-bound entitlement are separate facts. */
class License_Client {
	const API_BASE = 'https://www.chargeforms.com/api/v1/license';
	public static function activate( $key, $site ) { return self::request( 'activate', $key, $site ); }
	public static function deactivate( $key, $site ) { return self::request( 'deactivate', $key, $site ); }
	public static function verify( $key, $site ) { return self::request( 'verify', $key, $site ); }
	public static function valid_key_format( $key ) {
		return is_string( $key ) && 1 === preg_match( '/^CHRG-(FREE|SNGL|AGCY|UNLD)(?:-[A-HJ-NP-Z2-9]{4}){3,4}$/', strtoupper( trim( $key ) ) );
	}
	public static function site_hash( $site ) {
		$url = wp_parse_url( trim( $site ) );
		if ( ! is_array( $url ) || empty( $url['host'] ) || ! in_array( strtolower( $url['scheme'] ?? '' ), [ 'http', 'https' ], true ) || isset( $url['user'] ) || isset( $url['pass'] ) ) { return ''; }
		$host = preg_replace( '/^www\./', '', strtolower( $url['host'] ) );
		$port = isset( $url['port'] ) && ! in_array( (int) $url['port'], [ 80, 443 ], true ) ? ':' . $url['port'] : '';
		return hash( 'sha256', $host . $port . rtrim( $url['path'] ?? '', '/' ) );
	}
	private static function failure( $error, $temporary = false ) {
		return [ 'success' => false, 'temporary' => $temporary, 'error' => $error ];
	}
	private static function request( $action, $key, $site ) {
		if ( ! self::valid_key_format( $key ) || '' === self::site_hash( $site ) ) {
			return self::failure( __( 'Enter a valid ChargeForms license key and site URL.', 'chargeforms' ) );
		}
		$response = wp_remote_post( self::API_BASE . '/' . $action, [
			'timeout' => 10, 'headers' => [ 'Content-Type' => 'application/json' ],
			'body' => wp_json_encode( [ 'license_key' => strtoupper( trim( $key ) ), 'site_url' => $site ] ),
		] );
		if ( is_wp_error( $response ) ) { return self::failure( __( 'License service is temporarily unreachable. Verification will retry.', 'chargeforms' ), true ); }
		$code = wp_remote_retrieve_response_code( $response );
		$body = json_decode( wp_remote_retrieve_body( $response ), true );
		if ( 429 === $code || $code >= 500 ) {
			return self::failure( is_array( $body ) && ! empty( $body['error'] ) ? (string) $body['error'] : __( 'License service is temporarily unavailable.', 'chargeforms' ), true );
		}
		if ( ! is_array( $body ) || $code < 200 || $code >= 300 || true !== ( $body['success'] ?? false ) ) {
			return self::failure( is_array( $body ) && ! empty( $body['error'] ) ? (string) $body['error'] : __( 'This license is not valid on this site.', 'chargeforms' ) );
		}
		if ( 'deactivate' === $action ) {
			return true === ( $body['deactivated'] ?? false ) ? [ 'success' => true ] : self::failure( __( 'Site deactivation was not confirmed.', 'chargeforms' ), true );
		}
		if ( false === ( $body['valid'] ?? null ) ) {
			return self::failure( __( 'This license is not valid on this site.', 'chargeforms' ) );
		}
		$plan = $body['plan'] ?? '';
		$limits = [ 'single' => 1, 'agency' => 5, 'unlimited' => null ];
		if ( ! is_string( $plan ) || ! array_key_exists( $plan, $limits ) || ! array_key_exists( 'activation_limit', $body ) || $limits[ $plan ] !== $body['activation_limit'] ) {
			return self::failure( __( 'The license service returned incomplete plan information.', 'chargeforms' ), true );
		}
		if ( true !== ( $body['valid'] ?? false ) || 'active' !== ( $body['status'] ?? '' ) || true !== ( $body['activated_on_this_site'] ?? false ) || self::site_hash( $site ) !== ( $body['site_hash'] ?? '' ) ) {
			return self::failure( __( 'This license is not valid on this site.', 'chargeforms' ) );
		}
		if ( ! array_key_exists( 'expires_at', $body ) || ( null !== $body['expires_at'] && ( ! is_string( $body['expires_at'] ) || false === strtotime( $body['expires_at'] ) || strtotime( $body['expires_at'] ) <= time() ) ) ) {
			return self::failure( __( 'This license has expired or its expiry could not be verified.', 'chargeforms' ) );
		}
		return [ 'success' => true, 'plan' => $plan, 'activation_limit' => $body['activation_limit'], 'site_hash' => $body['site_hash'], 'expires_at' => $body['expires_at'] ];
	}
}