<?php
/**
 * The "Try it on" button and dialog on product pages.
 *
 * @package Fitzaro
 */

namespace Fitzaro\Storefront;

use Fitzaro\Api\ProductCheck;
use Fitzaro\Api\RestController;
use Fitzaro\Prompt\ProductType;
use Fitzaro\Prompt\TypeResolver;
use Fitzaro\Settings;
use Fitzaro\SystemCheck;

defined( 'ABSPATH' ) || exit;

/**
 * The markup lives in templates/try-on.php, which a theme can override (fitzaro/try-on.php);
 * styles use CSS custom properties a theme can set (see docs/CUSTOMIZING.md).
 *
 * Buttons carry both "button" (classic themes) and "wp-element-button" (block themes) so they
 * look like the theme's own buttons.
 *
 * Decision 2026-10-28: the storefront uses the WordPress Interactivity API only (no build step,
 * no jQuery). The markup holds no per-visitor data, so cached product pages stay correct; the
 * REST nonce is added only for logged-in users, whose pages are not cached.
 */
final class Button {

	public const HANDLE = 'fitzaro-tryon';

	/**
	 * Whether the button was printed on this page already (classic hook and block filter both fire on some themes).
	 *
	 * @var bool
	 */
	private static $rendered = false;

	/**
	 * Hooks the button into classic and block product templates.
	 */
	public static function register(): void {
		add_action( 'woocommerce_after_add_to_cart_form', array( self::class, 'print_button' ) );
		add_filter( 'render_block_woocommerce/add-to-cart-form', array( self::class, 'append_to_block' ), 10, 1 );
		add_action( 'wp_enqueue_scripts', array( self::class, 'register_assets' ) );
	}

	/**
	 * Registers the script module and stylesheet (enqueued only when the button is printed).
	 */
	public static function register_assets(): void {
		/**
		 * Whether to load Fitzaro's stylesheet. Return false when the theme styles the dialog itself.
		 *
		 * @since 1.0.0
		 *
		 * @param bool $load Load the default styles.
		 */
		if ( false !== apply_filters( 'fitzaro/load_styles', true ) ) {
			wp_register_style( self::HANDLE, FITZARO_URL . 'assets/tryon.css', array(), self::version( 'assets/tryon.css' ) );
		}

		if ( function_exists( 'wp_register_script_module' ) ) {
			wp_register_script_module( self::HANDLE, FITZARO_URL . 'assets/view.js', array( '@wordpress/interactivity' ), self::version( 'assets/view.js' ) );
		}
	}

	/**
	 * Asset version: the plugin version, plus the file's modification time with SCRIPT_DEBUG so
	 * browsers pick up edits during development.
	 *
	 * @param string $file Path relative to the plugin folder.
	 */
	private static function version( string $file ): string {
		if ( defined( 'SCRIPT_DEBUG' ) && SCRIPT_DEBUG ) {
			$time = filemtime( FITZARO_PATH . $file );
			if ( false !== $time ) {
				return FITZARO_VERSION . '.' . $time;
			}
		}

		return FITZARO_VERSION;
	}

	/**
	 * Classic templates: prints the button after the add-to-cart form.
	 */
	public static function print_button(): void {
		echo self::html(); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped -- Built from escaped parts in html().
	}

	/**
	 * Block templates: appends the button to the Add to Cart form block.
	 *
	 * @param mixed $content Block HTML.
	 * @return mixed
	 */
	public static function append_to_block( $content ) {
		return is_string( $content ) ? $content . self::html() : $content;
	}

	/**
	 * The widget for the current product, or '' when try-on is not offered for it.
	 */
	public static function html(): string {
		if ( self::$rendered || ! function_exists( 'wp_interactivity_process_directives' ) || ! is_product() || ! Settings::enabled() ) {
			return '';
		}

		$product = function_exists( 'wc_get_product' ) ? wc_get_product() : null;
		if ( ! $product instanceof \WC_Product || null !== ProductCheck::problem( $product->get_id(), 0 ) || ! SystemCheck::is_ready() ) {
			return '';
		}

		$type = (string) TypeResolver::for_product( $product->get_id() );

		self::$rendered = true;
		self::enqueue();

		$fitzaro = array(
			'id'      => 'fitzaro-' . $product->get_id(),
			'type'    => $type,
			'tip'     => self::tip( $type ),
			'consent' => self::consent(),
			'context' => wp_interactivity_data_wp_context( self::context( $product->get_id(), $product->is_type( 'variable' ) ) ),
		);

		ob_start();
		include self::template();
		return wp_interactivity_process_directives( (string) ob_get_clean() );
	}

	/**
	 * Path of the dialog template: the theme's copy (yourtheme/fitzaro/try-on.php) when there is one.
	 */
	private static function template(): string {
		$template = locate_template( 'fitzaro/try-on.php' );
		$template = '' !== $template ? $template : FITZARO_PATH . 'templates/try-on.php';

		/**
		 * Filters the path of the try-on dialog template.
		 *
		 * @since 1.0.0
		 *
		 * @param string $template Absolute path.
		 */
		return self::readable( apply_filters( 'fitzaro/template', $template ) ) ?? FITZARO_PATH . 'templates/try-on.php';
	}

	/**
	 * The path when it names a readable file. A filter can return anything.
	 *
	 * @param mixed $path Filter result.
	 */
	private static function readable( $path ): ?string {
		return is_string( $path ) && is_readable( $path ) ? $path : null;
	}

	/**
	 * Initial context of one widget.
	 *
	 * @param int  $product_id  Product.
	 * @param bool $is_variable Whether the product has variations.
	 * @return array<string, mixed>
	 */
	private static function context( int $product_id, bool $is_variable ): array {
		return array(
			'productId'    => $product_id,
			'isVariable'   => $is_variable,
			'needsVariant' => false,
			'showForm'     => true,
			'busy'         => false,
			'done'         => false,
			'hasFile'      => false,
			'previewUrl'   => '',
			'dragging'     => false,
			'position'     => 50,
			'imageUrl'     => '',
			'photo'        => '',
			'tryonId'      => '',
			'status'       => '',
			'error'        => '',
		);
	}

	/**
	 * Enqueues the assets and the shared state (API URL, nonce, texts).
	 */
	private static function enqueue(): void {
		// Block themes render the template before wp_enqueue_scripts runs, so register here too.
		if ( ! wp_style_is( self::HANDLE, 'registered' ) ) {
			self::register_assets();
		}
		if ( wp_style_is( self::HANDLE, 'registered' ) ) {
			wp_enqueue_style( self::HANDLE );
		}
		if ( function_exists( 'wp_enqueue_script_module' ) ) {
			wp_enqueue_script_module( self::HANDLE );
		}

		wp_interactivity_state(
			'fitzaro',
			array(
				'api'   => untrailingslashit( rest_url( RestController::NAMESPACE ) ),
				'nonce' => is_user_logged_in() ? wp_create_nonce( 'wp_rest' ) : '',
				'i18n'  => array(
					'uploading' => __( 'Uploading your photo…', 'fitzaro' ),
					'working'   => __( 'Creating your preview. This can take up to a minute…', 'fitzaro' ),
					'ready'     => __( 'Your preview is ready.', 'fitzaro' ),
					'deleted'   => __( 'Your photo and preview were deleted.', 'fitzaro' ),
					'failed'    => __( 'The preview could not be created. Please try again later.', 'fitzaro' ),
					'tooLong'   => __( 'This is taking longer than expected. Please try again later.', 'fitzaro' ),
					'offline'   => __( 'Could not connect. Check your internet connection and try again.', 'fitzaro' ),
					'wrongType' => __( 'Please choose a JPEG, PNG or WebP photo.', 'fitzaro' ),
				),
			)
		);
	}

	/**
	 * What makes a good photo for this kind of product.
	 *
	 * @param string $type ProductType constant.
	 */
	private static function tip( string $type ): string {
		switch ( $type ) {
			case ProductType::EYEWEAR:
				return __( 'Use a well-lit photo of your face from the front, with nothing covering your eyes.', 'fitzaro' );
			case ProductType::DRESS:
				return __( 'Use a well-lit, full-length photo of yourself from the front, standing straight.', 'fitzaro' );
			default:
				return __( 'Use a well-lit photo of yourself from the front, with your upper body fully visible.', 'fitzaro' );
		}
	}

	/**
	 * Consent text, with a link to the privacy policy when the site has one.
	 */
	private static function consent(): string {
		$text = esc_html__( 'Your photo is sent to OpenAI to create this preview. This store deletes it within 24 hours, and you can delete it sooner.', 'fitzaro' );

		$policy = get_privacy_policy_url();
		if ( '' !== $policy ) {
			$text .= ' <a href="' . esc_url( $policy ) . '">' . esc_html__( 'Privacy policy', 'fitzaro' ) . '</a>';
		}

		return $text;
	}
}