<?php namespace EmailLog\Addon\License;

use EmailLog\Addon\API\EDDAPI;

defined( 'ABSPATH' ) || exit; // Exit if accessed directly.

/**
 * Base class for for Bundle License and Add-on License.
 *
 * @since 2.0.0
 */
abstract class BaseLicense {

	protected $addon_name;
	protected $license_key;
	protected $license_data;

	/**
	 * EDD API Wrapper.
	 *
	 * @var \EmailLog\Addon\API\EDDAPI
	 */
	protected $edd_api;

	/**
	 * Is the license activated and valid?
	 *
	 * @return bool True if license is active, False otherwise.
	 */
	abstract public function is_valid();

	/**
	 * Get the option name in which license data will be stored.
	 *
	 * @return string Option name.
	 */
	abstract protected function get_option_name();

	/**
	 * Construct a new License object.
	 * If the API Wrapper is not provided, then a new one is initialized.
	 *
	 * @param \EmailLog\Addon\API\EDDAPI|null $edd_api (Optional) EDD API Wrapper instance. Default is null.
	 */
	public function __construct( $edd_api = null ) {
		if ( is_null( $edd_api ) ) {
			$edd_api = new EDDAPI();
		}

		$this->edd_api = $edd_api;
	}

	/**
	 * Set the license Key.
	 *
	 * @param string $license_key License Key.
	 */
	public function set_license_key( $license_key ) {
		$this->license_key = $license_key;
	}

	/**
	 * Get the license key.
	 *
	 * @return string|null License Key.
	 */
	public function get_license_key() {
		return $this->license_key;
	}

	/**
	 * Set add-on name.
	 *
	 * @param string $addon_name Add-on Name.
	 */
	public function set_addon_name( $addon_name ) {
		$this->addon_name = $addon_name;
	}

	/**
	 * Get the add-on name.
	 *
	 * @return string Add-on name.
	 */
	public function get_addon_name() {
		return $this->addon_name;
	}

	/**
	 * Get the expiry date of the license.
	 *
	 * @return string|false Expiry date in `yyyy-mm-dd hh:mm:ss` format if license is valid, False otherwise.
	 */
	public function get_expiry_date() {
		if ( ! empty( $this->license_data ) && isset( $this->license_data->expires ) ) {
			return $this->license_data->expires;
		}

		return false;
	}

	/**
	 * Activate License by calling EDD API.
	 * The license data returned by API is stored in an option.
	 *
	 * @return object API Response JSON Object.
	 * @throws \Exception In case of communication errors or License Issues.
	 */
	public function activate() {
		$response = $this->edd_api->activate_license( $this->get_license_key(), $this->get_addon_name() );

		if ( $response->success && 'valid' === $response->license ) {
			$response->license_key = $this->get_license_key();

			$this->store( $response );
			return $response;
		}

		switch ( $response->error ) {
			case 'expired':
				$message = sprintf(
					__( 'Your license key expired on %s.' , 'email-log'),
					date_i18n( get_option( 'date_format' ), strtotime( $response->expires, current_time( 'timestamp' ) ) )
				);
				break;

			case 'revoked':
				$message = __( 'Your license key has been disabled.' , 'email-log');
				break;

			case 'missing':
				$message = __( 'Your license key is invalid.' , 'email-log');
				break;

			case 'invalid':
			case 'site_inactive':
				$message = __( 'Your license is not active for this URL.' , 'email-log');
				break;

			case 'item_name_mismatch':
				$message = sprintf( __( 'Your license key is not valid for %s.' , 'email-log'), $this->get_addon_name() );
				break;

			case 'no_activations_left':
				$message = __( 'Your license key has reached its activation limit.' , 'email-log');
				break;

			default:
				$message = __( 'An error occurred, please try again.' , 'email-log');
				break;
		}

		throw new \Exception( $message );
	}

	/**
	 * Deactivate the license by calling EDD API.
	 * The stored license data will be cleared.
	 *
	 * @return object API Response JSON object.
	 * @throws \Exception In case of communication errors.
	 */
	public function deactivate() {
		$response = $this->edd_api->deactivate_license( $this->get_license_key(), $this->get_addon_name() );

		if ( $response->success && 'deactivated' === $response->license ) {
			$this->clear();
			return $response;
		}

		$message = __( 'An error occurred, please try again.', 'email-log' );

		if ( isset( $response->error ) ) {
			$message .= ' ' . $response->error;
		}

		throw new \Exception( $message );
	}

	/**
	 * Get version information by calling EDD API.
	 * // TODO: Currently not used. Will be removed eventually.
	 *
	 * @return object API Response JSON Object.
	 * @throws \Exception In case of communication errors.
	 */
	public function get_version() {
		$response = $this->edd_api->get_version( $this->get_license_key(), $this->get_addon_name() );

		if ( isset( $response->new_version ) && ! isset( $response->msg ) ) {
			return $response;
		}

		$message = __( 'An error occurred, please try again', 'email-log' ) . $response->error;
		throw new \Exception( $message );
	}

	/**
	 * Load the license data from DB option.
	 */
	public function load() {
		$this->license_data = get_option( $this->get_option_name(), null );
	}

	/**
	 * Store License data in DB option.
	 *
	 * @access protected
	 *
	 * @param object $license_data License data.
	 */
	protected function store( $license_data ) {
		$this->license_data = $license_data;
		update_option( $this->get_option_name(), $license_data );
	}

	/**
	 * Clear stored license data.
	 *
	 * @access protected
	 */
	protected function clear() {
		$this->license_data = null;
		$this->license_key = null;
		delete_option( $this->get_option_name() );
	}
}