<?php
/**
 * Main Plugin Class
 *
 * @package Magdev\WcComposableProduct
 */

namespace Magdev\WcComposableProduct;

defined( 'ABSPATH' ) || exit;

/**
 * Main plugin class - Singleton pattern
 */
class Plugin {
	/**
	 * The single instance of the class
	 *
	 * @var Plugin
	 */
	protected static $instance = null;

	/**
	 * Twig environment
	 *
	 * @var \Twig\Environment
	 */
	private $twig = null;

	/**
	 * Main Plugin Instance
	 *
	 * Ensures only one instance is loaded or can be loaded.
	 *
	 * @return Plugin
	 */
	public static function instance() {
		if ( is_null( self::$instance ) ) {
			self::$instance = new self();
		}
		return self::$instance;
	}

	/**
	 * Constructor
	 */
	private function __construct() {
		$this->init_hooks();
		$this->init_twig();
		$this->includes();
	}

	/**
	 * Hook into WordPress and WooCommerce
	 */
	private function init_hooks() {
		// Register product type
		add_filter( 'product_type_selector', array( $this, 'add_product_type' ) );
		add_filter( 'woocommerce_product_class', array( $this, 'product_class' ), 10, 2 );

		// Enqueue scripts and styles
		add_action( 'wp_enqueue_scripts', array( $this, 'enqueue_frontend_scripts' ) );
		add_action( 'admin_enqueue_scripts', array( $this, 'enqueue_admin_scripts' ) );

		// Admin settings
		add_filter( 'woocommerce_get_settings_pages', array( $this, 'add_settings_page' ) );
	}

	/**
	 * Initialize Twig template engine
	 */
	private function init_twig() {
		$loader     = new \Twig\Loader\FilesystemLoader( WC_COMPOSABLE_PRODUCT_PATH . 'templates' );
		$this->twig = new \Twig\Environment(
			$loader,
			array(
				'cache'       => WC_COMPOSABLE_PRODUCT_PATH . 'cache',
				'auto_reload' => true,
				'debug'       => defined( 'WP_DEBUG' ) && WP_DEBUG,
			)
		);

		// Add WordPress functions to Twig
		$this->twig->addFunction(
			new \Twig\TwigFunction(
				'__',
				function ( $text ) {
					// phpcs:ignore WordPress.WP.I18n.NonSingularStringLiteralText -- dynamic Twig template strings.
					return __( $text, 'wc-composable-product' );
				}
			)
		);
		$this->twig->addFunction( new \Twig\TwigFunction( 'esc_html', 'esc_html' ) );
		$this->twig->addFunction( new \Twig\TwigFunction( 'esc_attr', 'esc_attr' ) );
		$this->twig->addFunction( new \Twig\TwigFunction( 'esc_url', 'esc_url' ) );
		$this->twig->addFunction( new \Twig\TwigFunction( 'wc_price', 'wc_price' ) );

		// Add WordPress escaping functions as Twig filters
		$this->twig->addFilter( new \Twig\TwigFilter( 'esc_html', 'esc_html' ) );
		$this->twig->addFilter( new \Twig\TwigFilter( 'esc_attr', 'esc_attr' ) );
		$this->twig->addFilter( new \Twig\TwigFilter( 'esc_url', 'esc_url' ) );
	}

	/**
	 * Include required files
	 */
	private function includes() {
		// Note: Settings.php is NOT included here because it extends WC_Settings_Page
		// which isn't loaded until later. It's included in add_settings_page() instead.
		require_once WC_COMPOSABLE_PRODUCT_PATH . 'includes/Admin/ProductData.php';
		require_once WC_COMPOSABLE_PRODUCT_PATH . 'includes/ProductType.php';
		require_once WC_COMPOSABLE_PRODUCT_PATH . 'includes/StockManager.php';
		require_once WC_COMPOSABLE_PRODUCT_PATH . 'includes/CartHandler.php';
		require_once WC_COMPOSABLE_PRODUCT_PATH . 'includes/ProductSelector.php';

		// Initialize components
		new Admin\ProductData();
		new CartHandler();
	}

	/**
	 * Add composable product type to selector
	 *
	 * @param array $types Product types
	 * @return array
	 */
	public function add_product_type( $types ) {
		$types['composable'] = __( 'Composable product', 'wc-composable-product' );
		return $types;
	}

	/**
	 * Use custom product class for composable products
	 *
	 * @param string $classname Product class name
	 * @param string $product_type Product type
	 * @return string
	 */
	public function product_class( $classname, $product_type ) {
		if ( 'composable' === $product_type ) {
			$classname = 'Magdev\WcComposableProduct\ProductType';
		}
		return $classname;
	}

	/**
	 * Enqueue frontend scripts and styles
	 */
	public function enqueue_frontend_scripts() {
		if ( is_product() ) {
			wp_enqueue_style(
				'wc-composable-product',
				WC_COMPOSABLE_PRODUCT_URL . 'assets/css/frontend.css',
				array(),
				WC_COMPOSABLE_PRODUCT_VERSION
			);

			wp_enqueue_script(
				'wc-composable-product',
				WC_COMPOSABLE_PRODUCT_URL . 'assets/js/frontend.js',
				array( 'jquery' ),
				WC_COMPOSABLE_PRODUCT_VERSION,
				true
			);

			wp_localize_script(
				'wc-composable-product',
				'wcComposableProduct',
				array(
					'ajax_url'     => admin_url( 'admin-ajax.php' ),
					'nonce'        => wp_create_nonce( 'wc_composable_product_nonce' ),
					'i18n'         => array(
						'select_items' => __( 'Please select items', 'wc-composable-product' ),
						'max_items'    => __( 'Maximum items selected', 'wc-composable-product' ),
						'min_items'    => __( 'Please select at least one item', 'wc-composable-product' ),
					),
					'price_format' => array(
						'currency_symbol'    => get_woocommerce_currency_symbol(),
						'decimal_separator'  => wc_get_price_decimal_separator(),
						'thousand_separator' => wc_get_price_thousand_separator(),
						'decimals'           => wc_get_price_decimals(),
						'price_format'       => get_woocommerce_price_format(),
					),
				)
			);
		}
	}

	/**
	 * Enqueue admin scripts and styles
	 */
	public function enqueue_admin_scripts( $hook ) {
		if ( 'post.php' === $hook || 'post-new.php' === $hook ) {
			global $post_type;
			if ( 'product' === $post_type ) {
				wp_enqueue_style(
					'wc-composable-product-admin',
					WC_COMPOSABLE_PRODUCT_URL . 'assets/css/admin.css',
					array(),
					WC_COMPOSABLE_PRODUCT_VERSION
				);

				wp_enqueue_script(
					'wc-composable-product-admin',
					WC_COMPOSABLE_PRODUCT_URL . 'assets/js/admin.js',
					array( 'jquery', 'wc-admin-product-meta-boxes' ),
					WC_COMPOSABLE_PRODUCT_VERSION,
					true
				);
			}
		}
	}

	/**
	 * Add settings page to WooCommerce
	 *
	 * @param array $settings WooCommerce settings pages
	 * @return array
	 */
	public function add_settings_page( $settings ) {
		// Include Settings.php here, when WC_Settings_Page is guaranteed to be loaded
		require_once WC_COMPOSABLE_PRODUCT_PATH . 'includes/Admin/Settings.php';
		$settings[] = new Admin\Settings();
		return $settings;
	}

	/**
	 * Get Twig environment
	 *
	 * @return \Twig\Environment
	 */
	public function get_twig() {
		return $this->twig;
	}

	/**
	 * Render a Twig template
	 *
	 * @param string $template Template name
	 * @param array $context Template variables
	 * @return string
	 */
	public function render_template( $template, $context = array() ) {
		return $this->twig->render( $template, $context );
	}
}