<?php
/**
 * Post-editor suggestion metabox.
 *
 * @package Postlinkly
 * @since   1.0.0
 */

declare(strict_types=1);

namespace Postlinkly\Admin\MetaBox;

use Postlinkly\Admin\AdminUrls;
use Postlinkly\Admin\Assets\AssetRegistrar;
use Postlinkly\Admin\Icons;
use Postlinkly\Capabilities\CapabilityMap;
use Postlinkly\Hooks\ServiceProvider;

/**
 * Post-editor suggestion metabox.
 *
 * Renders a sidebar metabox with:
 *   - A stats row (inbound / outbound / external link counts).
 *   - A "Find Link Suggestions" button that opens a full-screen overlay
 *     panel with suggestion cards, bulk-select, and per-card Insert buttons.
 *
 * The overlay panel is injected into the page DOM by the metabox render
 * method and controlled entirely by metabox.js. No page reload is needed
 * after inserting links — the card is marked as inserted in place.
 *
 * @since 1.0.0
 */
final class SuggestionMetaBox implements ServiceProvider {

	/**
	 * Registers Plugin service hooks.
	 *
	 * @since 1.0.0
	 *
	 * @return array<int, array<int, mixed>>
	 */
	public function get_hooks(): array {
		return array(
			array( 'add_meta_boxes', array( $this, 'register' ) ),
			array( 'admin_enqueue_scripts', array( $this, 'enqueue_assets' ), 20, 1 ),
		);
	}

	/**
	 * Registers the metabox on all post types that support the editor.
	 *
	 * In the block editor (Gutenberg), the PluginSidebar registered by
	 * `gutenberg-sidebar.js` provides the full experience. The classic
	 * metabox is only shown when the block editor is not active for the
	 * current post type (e.g. Classic Editor plugin installed, or a post
	 * type that has `show_in_rest => false`).
	 *
	 * @since 1.0.0
	 * @hook  add_meta_boxes
	 *
	 * @return void
	 */
	public function register(): void {
		if ( ! current_user_can( CapabilityMap::for( 'manage_links' ) ) ) {
			return;
		}

		$post_types = get_post_types( array( 'show_ui' => true ) );
		foreach ( $post_types as $post_type ) {
			if ( ! post_type_supports( $post_type, 'editor' ) ) {
				continue;
			}

			// Skip post types that use the block editor — the Gutenberg
			// sidebar handles those. The metabox is only for Classic Editor.
			if ( $this->uses_block_editor( $post_type ) ) {
				continue;
			}

			add_meta_box(
				'postlinkly-suggestions',
				__( 'Postlinkly', 'postlinkly' ),
				array( $this, 'render' ),
				$post_type,
				'normal',
				'default'
			);
		}
	}

	/**
	 * Returns whether a post type uses the block editor.
	 *
	 * @since 1.0.0
	 *
	 * @param string $post_type Post type slug.
	 *
	 * @return bool
	 */
	private function uses_block_editor( string $post_type ): bool {
		// Classic Editor plugin sets this filter to return false.
		if ( function_exists( 'use_block_editor_for_post_type' ) ) {
			return (bool) use_block_editor_for_post_type( $post_type );
		}
		// Gutenberg is available when the REST API supports the post type.
		$post_type_obj = get_post_type_object( $post_type );
		return null !== $post_type_obj && ! empty( $post_type_obj->show_in_rest );
	}

	/**
	 * Enqueues the metabox JS and CSS on post-edit screens.
	 *
	 * On block-editor screens, enqueues the Gutenberg sidebar plugin.
	 * On classic-editor screens, enqueues the overlay metabox JS.
	 *
	 * @since 1.0.0
	 * @hook  admin_enqueue_scripts
	 *
	 * @param string $hook_suffix Current admin page hook suffix.
	 *
	 * @return void
	 */
	public function enqueue_assets( string $hook_suffix ): void {
		if ( ! in_array( $hook_suffix, array( 'post.php', 'post-new.php' ), true ) ) {
			return;
		}

		$post_id = isset( $_GET['post'] ) ? absint( $_GET['post'] ) : 0; // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- Read-only post ID for asset localisation.

		// Determine the post type so we know which editor is active.
		$post_type = 'post';
		if ( $post_id > 0 ) {
			$queried_post = get_post( $post_id );
			if ( null !== $queried_post ) {
				$post_type = (string) $queried_post->post_type;
			}
		} elseif ( isset( $_GET['post_type'] ) ) { // phpcs:ignore WordPress.Security.NonceVerification.Recommended
			$post_type = sanitize_key( (string) $_GET['post_type'] ); // phpcs:ignore WordPress.Security.NonceVerification.Recommended
		}

		wp_enqueue_style( AssetRegistrar::HANDLE_BASE_CSS );
		wp_enqueue_style( AssetRegistrar::HANDLE_MODAL_CSS );
		wp_enqueue_script( AssetRegistrar::HANDLE_ADMIN_JS );

		// Shared localisation data needed by both the metabox and the sidebar.
		$localize_data = array(
			'postId'      => $post_id,
			// Stamped into the suggestion CSV. A support report that does not
			// say which build produced it cannot be matched against a fix.
			'version'     => defined( 'POSTLINKLY_VERSION' ) ? (string) POSTLINKLY_VERSION : '',
			'ajaxUrl'     => admin_url( 'admin-ajax.php' ),
			'nonce'       => wp_create_nonce( 'postlinkly_get_suggestions' ),
			'insertNonce' => wp_create_nonce( 'postlinkly_insert_link' ),
			'logoUrl'     => POSTLINKLY_PLUGIN_URL . 'assets/images/logo.svg',
			'toolsUrl'    => AdminUrls::tools(),
			'i18n'        => array(
				'findSuggestions'      => __( 'Find Link Suggestions', 'postlinkly' ),
				'loading'              => __( 'Finding suggestions…', 'postlinkly' ),
				'noSuggestions'        => __( 'No suggestions found for this post.', 'postlinkly' ),
				'insert'               => __( 'Insert Link', 'postlinkly' ),
				'inserting'            => __( 'Inserting…', 'postlinkly' ),
				'inserted'             => __( 'Inserted', 'postlinkly' ),
				/* translators: %d: number of links to insert */
				'insertSelected'       => __( 'Insert %d Link(s)', 'postlinkly' ),
				'selectAll'            => __( 'Select All', 'postlinkly' ),
				/* translators: %d: number of suggestions found */
				'found'                => __( '%d found', 'postlinkly' ),
				/* translators: 1: number of selected suggestions, 2: total suggestions */
				'selectedOf'           => __( '%1$d of %2$d selected', 'postlinkly' ),
				'panelTitle'           => __( 'Link Suggestions', 'postlinkly' ),
				'panelSubtitle'        => __( 'Review and insert internal links into your post', 'postlinkly' ),
				'linkingTo'            => __( 'Linking to', 'postlinkly' ),
				'linkThisPhrase'       => __( 'Link this phrase', 'postlinkly' ),
				'cancel'               => __( 'Cancel', 'postlinkly' ),
				'inbound'              => __( 'Inbound', 'postlinkly' ),
				'outbound'             => __( 'Outbound', 'postlinkly' ),
				'external'             => __( 'External', 'postlinkly' ),
				'statsError'           => __( 'Run a scan to see link stats.', 'postlinkly' ),
				'insertError'          => __( 'Could not insert link. The anchor text may not be found in the post content.', 'postlinkly' ),
				/* translators: %d: number of suggestions available */
				'suggestionsAvailable' => __( '%d suggestions available', 'postlinkly' ),
			),
		);

		if ( $this->uses_block_editor( $post_type ) ) {
			// Block editor: enqueue the Gutenberg sidebar plugin.
			wp_enqueue_script( AssetRegistrar::HANDLE_GUTENBERG_JS );
			wp_localize_script( AssetRegistrar::HANDLE_GUTENBERG_JS, 'postlinklyMetabox', $localize_data );
		} else {
			// Classic editor: enqueue the overlay metabox JS.
			wp_localize_script(
				AssetRegistrar::HANDLE_ADMIN_JS,
				'postlinklyAdmin',
				array(
					'ajaxUrl' => admin_url( 'admin-ajax.php' ),
					'nonce'   => wp_create_nonce( 'postlinkly_admin' ),
					'i18n'    => array(
						'loading' => __( 'Loading…', 'postlinkly' ),
						'error'   => __( 'An error occurred. Please try again.', 'postlinkly' ),
						'saved'   => __( 'Saved.', 'postlinkly' ),
						'confirm' => __( 'Are you sure?', 'postlinkly' ),
					),
				)
			);
			wp_enqueue_script( AssetRegistrar::HANDLE_METABOX_JS );
			wp_localize_script( AssetRegistrar::HANDLE_METABOX_JS, 'postlinklyMetabox', $localize_data );
		}
	}

	/**
	 * Renders the metabox shell and the overlay panel container.
	 *
	 * The metabox shell shows stats + find button.
	 * The overlay panel is hidden until the find button is clicked.
	 *
	 * @since 1.0.0
	 *
	 * @param \WP_Post $post The post being edited.
	 *
	 * @return void
	 */
	public function render( \WP_Post $post ): void {
		$post_id = (int) $post->ID;
		?>
		<div id="postlinkly-metabox" data-post-id="<?php echo esc_attr( (string) $post_id ); ?>">

			<!-- Stats row -->
			<div class="pl-stats" id="pl-stats">
				<div class="pl-stat pl-stat-inbound">
					<div class="pl-stat-value" id="pl-stat-inbound">—</div>
					<div class="pl-stat-label pl-label-with-icon">
						<?php echo wp_kses( Icons::arrow_left( 12 ), Icons::allowed_html() ); ?>
						<span><?php esc_html_e( 'Inbound', 'postlinkly' ); ?></span>
					</div>
				</div>
				<div class="pl-stat pl-stat-outbound">
					<div class="pl-stat-value" id="pl-stat-outbound">—</div>
					<div class="pl-stat-label pl-label-with-icon">
						<?php echo wp_kses( Icons::arrow_right( 12 ), Icons::allowed_html() ); ?>
						<span><?php esc_html_e( 'Outbound', 'postlinkly' ); ?></span>
					</div>
				</div>
				<div class="pl-stat pl-stat-external">
					<div class="pl-stat-value" id="pl-stat-external">—</div>
					<div class="pl-stat-label pl-label-with-icon">
						<?php echo wp_kses( Icons::arrow_up_right( 12 ), Icons::allowed_html() ); ?>
						<span><?php esc_html_e( 'External', 'postlinkly' ); ?></span>
					</div>
				</div>
			</div>

			<!-- Find button -->
			<button type="button" id="pl-find-btn" class="button button-primary pl-find-btn">
				<svg width="13" height="13" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" style="vertical-align:middle;margin-right:5px;"><circle cx="11" cy="11" r="8"/><path d="m21 21-4.35-4.35"/></svg>
				<?php esc_html_e( 'Find Link Suggestions', 'postlinkly' ); ?>
			</button>

			<!-- Count badge (populated after load) -->
			<div id="pl-count-badge" class="pl-count-badge" style="display:none;"></div>

		</div>

		<!-- Overlay panel (hidden until find button clicked) -->
		<div id="pl-overlay" class="pl-overlay" style="display:none;" aria-modal="true" role="dialog">
			<div class="pl-panel" id="pl-panel">

				<!-- Panel header -->
				<div class="pl-panel-header">
					<div class="pl-panel-header-left">
						<div class="pl-panel-icon">
							<svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5"><path d="M10 13a5 5 0 0 0 7.54.54l3-3a5 5 0 0 0-7.07-7.07l-1.72 1.71"/><path d="M14 11a5 5 0 0 0-7.54-.54l-3 3a5 5 0 0 0 7.07 7.07l1.71-1.71"/></svg>
						</div>
						<div class="pl-panel-title">
							<h2><?php esc_html_e( 'Link Suggestions', 'postlinkly' ); ?></h2>
							<p><?php esc_html_e( 'Review and insert internal links into your post', 'postlinkly' ); ?></p>
						</div>
					</div>
					<button type="button" class="pl-close-btn" id="pl-close-btn" aria-label="<?php esc_attr_e( 'Close', 'postlinkly' ); ?>">
						<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5"><path d="M18 6 6 18M6 6l12 12"/></svg>
					</button>
				</div>

				<!-- Controls bar -->
				<div class="pl-controls" id="pl-controls" style="display:none;">
					<div class="pl-controls-left">
						<input type="checkbox" id="pl-select-all" class="pl-checkbox" checked>
						<label for="pl-select-all" class="pl-select-all-label"><?php esc_html_e( 'Select All', 'postlinkly' ); ?></label>
						<span class="pl-found-badge" id="pl-found-badge"></span>
					</div>
				</div>

				<!-- Suggestion list -->
				<div class="pl-suggestion-list" id="pl-suggestion-list">
					<div class="pl-panel-loading" id="pl-panel-loading">
						<span class="spinner is-active" style="float:none;margin:0;"></span>
						<span><?php esc_html_e( 'Finding link opportunities…', 'postlinkly' ); ?></span>
					</div>
				</div>

				<!-- Panel footer -->
				<div class="pl-panel-footer" id="pl-panel-footer" style="display:none;">
					<div class="pl-footer-info">
						<span id="pl-selected-info"></span>
					</div>
					<div class="pl-footer-actions">
						<button type="button" class="button pl-btn-cancel" id="pl-btn-cancel"><?php esc_html_e( 'Cancel', 'postlinkly' ); ?></button>
						<button type="button" class="button button-primary pl-btn-insert-all" id="pl-btn-insert-all" disabled><?php esc_html_e( 'Insert Links', 'postlinkly' ); ?></button>
					</div>
				</div>

			</div><!-- /pl-panel -->
		</div><!-- /pl-overlay -->
		<?php
	}
}