<?php
/**
 * Google Fonts Loader
 *
 * Handles loading Google Fonts based on block attributes.
 * Collects font families from blocks and enqueues them.
 *
 * @since      1.0.0
 * @package    Acumenpopup
 * @subpackage Acumenpopup/includes/Core
 */

namespace Acumenpopup\Core;

// Exit if accessed directly.
if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Class Fonts_Loader
 *
 * Manages Google Fonts loading for the plugin (Singleton).
 *
 * @since   1.0.0
 * @package Acumenpopup
 */
class Fonts_Loader {

	/**
	 * The single instance of the class.
	 *
	 * @since  1.0.0
	 * @access private
	 * @var    Fonts_Loader|null
	 */
	private static $instance = null;

	/**
	 * Collection of all fonts to load.
	 *
	 * @since  1.0.0
	 * @access private
	 * @var    array
	 */
	private static $all_fonts = array();

	/**
	 * System fonts that don't need Google Fonts loading.
	 *
	 * @since  1.0.0
	 * @access private
	 * @var    array
	 */
	private $system_fonts = array(
		'Default',
		'Arial',
		'Tahoma',
		'Verdana',
		'Helvetica',
		'Times New Roman',
		'Trebuchet MS',
		'Georgia',
	);

	/**
	 * Private constructor to prevent direct instantiation.
	 *
	 * @since  1.0.0
	 * @access private
	 */
	private function __construct() {
		$this->init_hooks();
	}

	/**
	 * Get the single instance of the Fonts_Loader class.
	 *
	 * @since  1.0.0
	 * @access public
	 *
	 * @return Fonts_Loader The single instance.
	 */
	public static function get_instance() {
		if ( is_null( self::$instance ) ) {
			self::$instance = new self();
		}

		return self::$instance;
	}

	/**
	 * Initialize WordPress hooks.
	 *
	 * @since  1.0.0
	 * @access private
	 *
	 * @return void
	 */
	private function init_hooks() {
		add_action( 'wp_enqueue_scripts', array( $this, 'enqueue_fonts' ), 9999 );
		add_action( 'admin_enqueue_scripts', array( $this, 'enqueue_fonts' ), 9999 );
		add_action( 'acumenpopup_render_block', array( $this, 'collect_block_fonts' ) );
	}

	/**
	 * Collect font families from a rendered block.
	 *
	 * Scans block attributes for font family settings and
	 * adds them to the fonts collection.
	 *
	 * @since  1.0.0
	 * @access public
	 *
	 * @param array $block The block data including attributes.
	 *
	 * @return void
	 */
	public function collect_block_fonts( $block ) {
		if ( ! isset( $block['attrs'] ) || ! is_array( $block['attrs'] ) ) {
			return;
		}

		$attributes = $block['attrs'];

		foreach ( $attributes as $key => $value ) {
			// Check for font family attributes.
			if (
				! empty( $value ) &&
				0 === strpos( $key, 'acumenpopup_' ) &&
				false !== strpos( $key, 'FontFamily' )
			) {
				self::$all_fonts[] = sanitize_text_field( $value );
			}
		}

		// Trigger font loading after collection.
		$this->enqueue_fonts();
	}

	/**
	 * Enqueue collected Google Fonts.
	 *
	 * Processes the collected fonts and enqueues them from Google Fonts API.
	 *
	 * @since  1.0.0
	 * @access public
	 *
	 * @return void
	 */
	public function enqueue_fonts() {
		if ( empty( self::$all_fonts ) || ! is_array( self::$all_fonts ) ) {
			return;
		}

		// Get unique fonts.
		$fonts = array_filter( array_unique( self::$all_fonts ) );

		if ( empty( $fonts ) ) {
			return;
		}

		// Font weight variations to include.
		$font_weights = ':100,200,300,400,500,600,700,800,900';

		foreach ( $fonts as $font ) {
			// Skip system fonts.
			if ( in_array( $font, $this->system_fonts, true ) || empty( $font ) ) {
				continue;
			}

			$font_slug   = str_replace( ' ', '+', trim( $font ) );
			$font_url    = apply_filters(
				'acumenpopup_google_font_url',
				add_query_arg(
					array( 'family' => $font_slug . $font_weights ),
					'https://fonts.googleapis.com/css'
				)
			);
			$font_handle = 'acumenpopup-font-' . sanitize_title( $font );

			// Register and enqueue the font.
			wp_register_style(
				$font_handle,
				esc_url( $font_url ),
				array(),
				ACUMENPOPUP_VERSION,
				'all'
			);

			wp_enqueue_style( $font_handle );
		}
	}

	/**
	 * Add a font to the collection manually.
	 *
	 * @since  1.0.0
	 * @access public
	 *
	 * @param string $font_family The font family name to add.
	 *
	 * @return void
	 */
	public function add_font( $font_family ) {
		if ( ! empty( $font_family ) ) {
			self::$all_fonts[] = sanitize_text_field( $font_family );
		}
	}

	/**
	 * Get all collected fonts.
	 *
	 * @since  1.0.0
	 * @access public
	 *
	 * @return array Array of collected font families.
	 */
	public function get_fonts() {
		return array_filter( array_unique( self::$all_fonts ) );
	}

	/**
	 * Clear all collected fonts.
	 *
	 * @since  1.0.0
	 * @access public
	 *
	 * @return void
	 */
	public function clear_fonts() {
		self::$all_fonts = array();
	}

	/**
	 * Prevent cloning of the instance.
	 *
	 * @since  1.0.0
	 * @access public
	 *
	 * @return void
	 */
	public function __clone() {
		_doing_it_wrong(
			__FUNCTION__,
			esc_html__( 'Cloning is forbidden.', 'acumen-popup' ),
			'1.0.0'
		);
	}

	/**
	 * Prevent unserializing of the instance.
	 *
	 * @since  1.0.0
	 * @access public
	 *
	 * @return void
	 */
	public function __wakeup() {
		_doing_it_wrong(
			__FUNCTION__,
			esc_html__( 'Unserializing is forbidden.', 'acumen-popup' ),
			'1.0.0'
		);
	}
}