<?php
/**
 * Fonts API for Google Fonts
 *
 * This class load the google fonts for style purpose.
 *
 * @link www.italystrap.com
 * @since 2.5.0
 *
 * @package ItalyStrap
 */

namespace ItalyStrap\Google;

if ( ! defined( 'ITALYSTRAP_PLUGIN' ) or ! ITALYSTRAP_PLUGIN ) {
	die();
}

use ItalyStrap\Config\Config_Interface;

/**
 * Web Font Loading class
 */
class Fonts {

	/**
	 * Google API font URL
	 *
	 * @var string
	 */
	protected $google_api_url = '';

	/**
	 * Google API Key
	 *
	 * @var string
	 */
	protected $google_api_key = '';

	/**
	 * relative path to the file json with all fonts preloaded
	 *
	 * @var string
	 */
	protected $api_fallback_file = '';

	/**
	 * Configuration for google http query params.
	 *
	 * @var array
	 */
	protected $http_query = array();

	protected static $fonts = array();

	/**
	 * Init the class.
	 *
	 * @param Config_Interface $config The class configuration.
	 */
	function __construct( Config_Interface $config ) {

		$this->config = $config->all();

		$this->google_api_url = 'https://www.googleapis.com/webfonts/v1/webfonts';

		$this->google_api_key = isset( $this->config['google_api_key'] ) ? esc_attr( $this->config['google_api_key'] ) : '';

		$this->http_query = array(
			'key'	=> $this->google_api_key,
		);

		$this->api_fallback_file = __DIR__ . DS . 'fonts/fonts.json';

		$this->variants = array(
			'100'		=> __( '100', 'italystrap' ),
			'100italic'	=> __( '100italic', 'italystrap' ),
			'200'		=> __( '200', 'italystrap' ),
			'200italic'	=> __( '200italic', 'italystrap' ),
			'300'		=> __( '300', 'italystrap' ),
			'300italic'	=> __( '300italic', 'italystrap' ),
			'regular'	=> __( 'Regular 400', 'italystrap' ),
			'italic'	=> __( 'Italic 400', 'italystrap' ),
			'500'		=> __( '500', 'italystrap' ),
			'500italic'	=> __( '500italic', 'italystrap' ),
			'600'		=> __( '600', 'italystrap' ),
			'600italic'	=> __( '600italic', 'italystrap' ),
			'700'		=> __( '700', 'italystrap' ),
			'700italic'	=> __( '700italic', 'italystrap' ),
			'800'		=> __( '800', 'italystrap' ),
			'800italic'	=> __( '800italic', 'italystrap' ),
			'900'		=> __( '900', 'italystrap' ),
			'900italic'	=> __( '900italic', 'italystrap' ),
		);

		$this->subsets = array(
			'bengali'		=> __( 'Bengali', 'italystrap' ),
			'cyrillic'		=> __( 'Cyrillic', 'italystrap' ),
			'cyrillic-ext'	=> __( 'Cyrillic Extended', 'italystrap' ),
			'devanagari'	=> __( 'Devanagari', 'italystrap' ),
			'greek'			=> __( 'Greek', 'italystrap' ),
			'greek-ext'		=> __( 'Greek Extended', 'italystrap' ),
			'gujarati'		=> __( 'Gujarati', 'italystrap' ),
			'hebrew'		=> __( 'Hebrew', 'italystrap' ),
			'khmer'			=> __( 'Khmer', 'italystrap' ),
			'latin'			=> __( 'Latin', 'italystrap' ),
			'latin-ext'		=> __( 'Latin Extended', 'italystrap' ),
			'tamil'			=> __( 'Tamil', 'italystrap' ),
			'telugu'		=> __( 'Telugu', 'italystrap' ),
			'thai'			=> __( 'Thai', 'italystrap' ),
			'vietnamese'	=> __( 'Vietnamese', 'italystrap' ),
		);
	}

	/**
	 * Flush transient
	 * Maybe flush at the 'update_option_' . $args['options_name'] ?
	 */
	public function flush_transient() {
		delete_transient( 'italystrap_google_fonts' );
	}

	/**
	 * Get the google fonts from the API or in the cache
	 *
	 * @return String
	 */
	public function get_remote_fonts() {

		if ( empty( $this->google_api_key ) ) {
			// return (array) $this->get_api_fallback()->items;
			return array();
		}

		// $this->flush_transient();
		
		if ( ! self::$fonts ) {
			self::$fonts = get_transient( 'italystrap_google_fonts' );
		}

		if ( false === self::$fonts ) {

			$font_content = wp_remote_get( $this->google_api_url . '?' . http_build_query( $this->http_query ), array( 'sslverify' => false ) );

			/**
			 * In case the url of the google fonts is wrong
			 * For example when is missing 'https:'
			 */
			if ( is_wp_error( $font_content ) ) {
				// return (array) $this->get_api_fallback()->items;
				return array();
			}

			self::$fonts = wp_remote_retrieve_body( $font_content );

			self::$fonts = (array) json_decode( self::$fonts );

			self::$fonts = $this->rename_key_by_font_family_name( self::$fonts );

			set_transient( 'italystrap_google_fonts', self::$fonts, MONTH_IN_SECONDS );
			/**
			 * Commented for better test in future
			 */
			// $this->set_api_fallback( self::$fonts );
		}

		/**
		 * self::$fonts->items or self::$fonts['items'] have to always return an array
		 */

		if ( is_object( self::$fonts ) ) {
			return self::$fonts->items;
		}

		if ( ! isset( self::$fonts['items'] ) ) {
			return array();
		}

		return (array) self::$fonts['items'];
	}

	/**
	 * If the we don't have a Google API key, or the request fails,
	 * use the contents of this file instead.
	 * 
	 * @author Paul Clark
	 * @link http://stylesplugin.com
	 * @file styles/styles-font-menu/classes/sfm-group-google.php
	 */
	public function get_api_fallback() {
		return json_decode( file_get_contents( $this->api_fallback_file ) );
	}

	/**
	 * Save Google Fonts API response to file for cases where we
	 * don't have an API key or the API request fails
	 * 
	 * @author Paul Clark
	 * @link http://stylesplugin.com
	 * @file styles/styles-font-menu/classes/sfm-group-google.php
	 */
	public function set_api_fallback( $fonts ) {
		if ( ! file_exists( $this->api_fallback_file ) || is_writable( $this->api_fallback_file ) ) {
			file_put_contents( $this->api_fallback_file, json_encode( $fonts ) );
		}
	}

	/**
	 * Get property
	 *
	 * @param  string $prop_name The name of the property to get.
	 * @return string            The value pf the property.
	 */
	public function get_property( $prop_name ) {

		if ( ! property_exists( $this, $prop_name ) ) {
			return null;
		}

		return $this->$prop_name;
	}

	/**
	 * Rename array key by font family name
	 *
	 * @param  array $items The array with Google fonts.
	 * @return array        Return the new array
	 */
	protected function rename_key_by_font_family_name( array $items = array() ) {

		if ( empty( $items['items'] ) ) {
			return $items;
		}

		$i = 0;
		foreach ( $items['items'] as $key => $object ) {
			$items['items'][ $object->family ] = $object;
			unset( $items['items'][ $i ] );
			$i++;
		}

		return $items;
	}
}