<?php
/**
 * Settings API screens and editor-independent post overrides.
 *
 * @package Tocnest
 */

defined( 'ABSPATH' ) || exit;

/** Administrative settings and per-post controls. */
class Tocnest_Admin {
	/** Register administrative hooks. */
	public static function boot() {
		add_action( 'admin_menu', array( __CLASS__, 'menu' ) );
		add_action( 'admin_init', array( __CLASS__, 'register' ) );
		add_action( 'add_meta_boxes', array( __CLASS__, 'metaboxes' ) );
		add_action( 'save_post', array( __CLASS__, 'save_meta' ) );
		add_action( 'admin_post_tocnest_reset', array( __CLASS__, 'reset' ) );
		add_action( 'admin_enqueue_scripts', array( __CLASS__, 'assets' ) );
	}

	/** Register the settings screen. */
	public static function menu() {
		add_options_page( __( 'Tocnest settings', 'tocnest' ), __( 'Tocnest', 'tocnest' ), 'manage_options', 'tocnest', array( __CLASS__, 'page' ) );
	}

	/** Register settings with the core nonce and capability-protected handler. */
	public static function register() {
		register_setting(
			'tocnest',
			'tocnest_settings',
			array(
				'type'              => 'array',
				'sanitize_callback' => array( __CLASS__, 'save_settings' ),
				'default'           => Tocnest_Settings::defaults(),
			)
		);
	}

	/**
	 * Merge a single settings tab with existing validated values.
	 *
	 * @param mixed $input Submitted values.
	 * @return array
	 */
	public static function save_settings( $input ) {
		if ( ! current_user_can( 'manage_options' ) ) {
			return Tocnest_Settings::get();
		}
		return array_merge( Tocnest_Settings::get(), Tocnest_Settings::sanitize( $input, true ) );
	}

	/**
	 * Translated tab names.
	 *
	 * @return array
	 */
	private static function tabs() {
		return array(
			'general'    => __( 'General', 'tocnest' ),
			'appearance' => __( 'Appearance', 'tocnest' ),
			'auto'       => __( 'Auto insert', 'tocnest' ),
			'advanced'   => __( 'Advanced', 'tocnest' ),
			'import'     => __( 'Import', 'tocnest' ),
		);
	}

	/**
	 * Field labels, grouped by tab.
	 *
	 * @return array
	 */
	private static function fields() {
		return array(
			'general'    => array(
				'title'        => __( 'Title text', 'tocnest' ),
				'show_title'   => __( 'Show title', 'tocnest' ),
				'title_tag'    => __( 'Title element', 'tocnest' ),
				'toggle'       => __( 'Show toggle button', 'tocnest' ),
				'label_show'   => __( 'Show button label', 'tocnest' ),
				'label_hide'   => __( 'Hide button label', 'tocnest' ),
				'collapsed'    => __( 'Start collapsed', 'tocnest' ),
				'min'          => __( 'Minimum headings', 'tocnest' ),
				'levels'       => __( 'Included heading levels', 'tocnest' ),
				'depth'        => __( 'Maximum nesting depth', 'tocnest' ),
				'hierarchical' => __( 'Hierarchical list', 'tocnest' ),
				'numbering'    => __( 'Numbering', 'tocnest' ),
				'suffix'       => __( 'Number suffix', 'tocnest' ),
			),
			'appearance' => array(
				'scheme'       => __( 'Color scheme', 'tocnest' ),
				'background'   => __( 'Background color', 'tocnest' ),
				'border'       => __( 'Border color', 'tocnest' ),
				'title_color'  => __( 'Title color', 'tocnest' ),
				'link'         => __( 'Link color', 'tocnest' ),
				'hover'        => __( 'Link hover color', 'tocnest' ),
				'visited'      => __( 'Visited link color', 'tocnest' ),
				'width'        => __( 'Width: auto, full, or CSS length', 'tocnest' ),
				'float'        => __( 'Float', 'tocnest' ),
				'title_size'   => __( 'Title font size', 'tocnest' ),
				'title_weight' => __( 'Title font weight', 'tocnest' ),
				'items_size'   => __( 'Items font size', 'tocnest' ),
				'markup'       => __( 'List markup', 'tocnest' ),
				'class'        => __( 'Extra container CSS classes', 'tocnest' ),
			),
			'auto'       => array(
				'auto'          => __( 'Automatically insert a TOC', 'tocnest' ),
				'post_types'    => __( 'Automatic insertion post types', 'tocnest' ),
				'position'      => __( 'Insertion position', 'tocnest' ),
				'anchor_types'  => __( 'Add anchors even without a TOC on these post types', 'tocnest' ),
				'metabox_types' => __( 'Show per-post controls on these post types', 'tocnest' ),
			),
			'advanced'   => array(
				'skip_levels'       => __( 'Excluded levels, for example h1,h5', 'tocnest' ),
				'skip_text'         => __( 'Skip headings by text, one per line; * matches any text', 'tocnest' ),
				'skip_class'        => __( 'Skip headings with these CSS classes', 'tocnest' ),
				'anchor_format'     => __( 'Anchor format', 'tocnest' ),
				'lowercase'         => __( 'Lowercase anchors', 'tocnest' ),
				'dashes'            => __( 'Replace underscores with dashes', 'tocnest' ),
				'smooth'            => __( 'Smooth scrolling', 'tocnest' ),
				'offset'            => __( 'Scroll offset in pixels', 'tocnest' ),
				'highlight'         => __( 'Highlight current section', 'tocnest' ),
				'nofollow'          => __( 'Add nofollow to TOC links', 'tocnest' ),
				'compat'            => __( 'Keep old shortcodes and blocks working', 'tocnest' ),
				'override_previous' => __( 'Allow automatic insertion while the previous plugin also inserts a TOC', 'tocnest' ),
			),
		);
	}

	/**
	 * Translate select option labels.
	 *
	 * @return array
	 */
	private static function choices() {
		return array(
			'none'               => __( 'None', 'tocnest' ),
			'decimal'            => __( 'Decimal', 'tocnest' ),
			'decimalnested'      => __( 'Nested decimal', 'tocnest' ),
			'roman'              => __( 'Roman', 'tocnest' ),
			'romannested'        => __( 'Nested Roman', 'tocnest' ),
			'dot'                => __( 'Dot (.)', 'tocnest' ),
			'roundbracket'       => __( 'Closing parenthesis', 'tocnest' ),
			'light'              => __( 'Light', 'tocnest' ),
			'dark'               => __( 'Dark', 'tocnest' ),
			'white'              => __( 'White', 'tocnest' ),
			'transparent'        => __( 'Transparent', 'tocnest' ),
			'inherit'            => __( 'Inherit from theme', 'tocnest' ),
			'left'               => __( 'Left', 'tocnest' ),
			'right'              => __( 'Right', 'tocnest' ),
			'center'             => __( 'Center', 'tocnest' ),
			'text'               => __( 'Heading text, transliterated', 'tocnest' ),
			'text_raw'           => __( 'Heading text, original characters', 'tocnest' ),
			'counter'            => __( 'Counter (toc-1)', 'tocnest' ),
			'beforefirstheading' => __( 'Before first heading', 'tocnest' ),
			'afterfirstheading'  => __( 'After first heading', 'tocnest' ),
			'afterfirstblock'    => __( 'After first paragraph or block', 'tocnest' ),
			'top'                => __( 'Top', 'tocnest' ),
			'bottom'             => __( 'Bottom', 'tocnest' ),
			'p'                  => __( 'Paragraph', 'tocnest' ),
			'div'                => __( 'Division', 'tocnest' ),
			'ol'                 => __( 'Ordered list', 'tocnest' ),
			'ul'                 => __( 'Unordered list', 'tocnest' ),
		);
	}

	/** Render the complete settings screen. */
	public static function page() {
		if ( ! current_user_can( 'manage_options' ) ) {
			return;
		}
		$tabs = self::tabs();
		$tab  = isset( $_GET['tab'] ) ? sanitize_key( wp_unslash( $_GET['tab'] ) ) : 'general'; // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- Read-only tab selection.
		$tab  = isset( $tabs[ $tab ] ) ? $tab : 'general';
		echo '<div class="wrap"><h1>' . esc_html__( 'Tocnest settings', 'tocnest' ) . '</h1><p>' . esc_html__( 'Fast, accessible navigation for your content. Every feature is included.', 'tocnest' ) . '</p>';
		settings_errors();
		if ( Tocnest_Migration::old_active() ) {
			echo '<div class="notice notice-warning inline"><p>' . esc_html__( 'The previous table of contents plugin is active. Deactivate it to avoid duplicate tables. Automatic insertion pauses while its auto insert is enabled, unless you override this in Advanced.', 'tocnest' ) . '</p></div>';
		}
		echo '<nav class="nav-tab-wrapper" aria-label="' . esc_attr__( 'Settings tabs', 'tocnest' ) . '">';
		foreach ( $tabs as $key => $label ) {
			echo '<a class="nav-tab ' . ( $key === $tab ? 'nav-tab-active' : '' ) . '" href="' . esc_url(
				add_query_arg(
					array(
						'page' => 'tocnest',
						'tab'  => $key,
					),
					admin_url( 'options-general.php' )
				)
			) . '">' . esc_html( $label ) . '</a>';
		}
		echo '</nav>';
		if ( 'import' === $tab ) {
			self::import_tab();
		} else {
			$settings = Tocnest_Settings::get();
			echo '<form action="' . esc_url( admin_url( 'options.php' ) ) . '" method="post">';
			settings_fields( 'tocnest' );
			echo '<table class="form-table" role="presentation">';
			foreach ( self::fields()[ $tab ] as $key => $label ) {
				echo '<tr><th scope="row"><label for="tocnest-' . esc_attr( $key ) . '">' . esc_html( $label ) . '</label></th><td>';
				self::field( $key, $settings[ $key ] );
				echo '</td></tr>';
			}
			echo '</table>';
			submit_button();
			echo '</form>';
		}
		self::action_form( 'tocnest_reset', __( 'Reset to defaults', 'tocnest' ) );
		echo '</div>';
	}

	/**
	 * Render one settings input with late escaping.
	 *
	 * @param string $key Setting key.
	 * @param mixed  $value Current value.
	 */
	private static function field( $key, $value ) {
		$name   = 'tocnest_settings[' . $key . ']';
		$id     = 'tocnest-' . $key;
		$enums  = Tocnest_Settings::enums();
		$labels = self::choices();
		if ( is_bool( $value ) ) {
			echo '<input type="hidden" name="' . esc_attr( $name ) . '" value="0"><input id="' . esc_attr( $id ) . '" name="' . esc_attr( $name ) . '" type="checkbox" value="1" ' . checked( $value, true, false ) . '>';
		} elseif ( is_array( $value ) ) {
			echo '<fieldset id="' . esc_attr( $id ) . '"><legend class="screen-reader-text">' . esc_html__( 'Select included values', 'tocnest' ) . '</legend><input type="hidden" name="' . esc_attr( $name ) . '[]" value="">';
			$items = 'levels' === $key ? array_combine( range( 1, 6 ), array( 'H1', 'H2', 'H3', 'H4', 'H5', 'H6' ) ) : wp_list_pluck( get_post_types( array( 'show_ui' => true ), 'objects' ), 'label' );
			foreach ( $items as $item => $label ) {
				echo '<label class="tocnest-choice"><input type="checkbox" name="' . esc_attr( $name ) . '[]" value="' . esc_attr( $item ) . '" ' . checked( in_array( $item, $value, true ), true, false ) . '> ' . esc_html( $label ) . '</label>';
			}
			echo '</fieldset>';
		} elseif ( isset( $enums[ $key ] ) ) {
			echo '<select id="' . esc_attr( $id ) . '" name="' . esc_attr( $name ) . '">';
			foreach ( $enums[ $key ] as $choice ) {
				echo '<option value="' . esc_attr( $choice ) . '" ' . selected( $choice, $value, false ) . '>' . esc_html( isset( $labels[ $choice ] ) ? $labels[ $choice ] : $choice ) . '</option>';
			}
			echo '</select>';
		} elseif ( 'skip_text' === $key ) {
			echo '<textarea id="' . esc_attr( $id ) . '" name="' . esc_attr( $name ) . '" rows="5" class="large-text">' . esc_textarea( $value ) . '</textarea>';
		} else {
			echo '<input id="' . esc_attr( $id ) . '" name="' . esc_attr( $name ) . '" type="' . ( is_int( $value ) ? 'number' : 'text' ) . '" value="' . esc_attr( $value ) . '" class="regular-text">';
		}
	}

	/** Render migration detection, reports and actions. */
	private static function import_tab() {
		$detected = Tocnest_Migration::detection();
		echo '<h2>' . esc_html__( 'Migrate your settings', 'tocnest' ) . '</h2><p>' . esc_html__( 'Import settings from the LuckyWP Table of Contents plugin. Tocnest is independent and is not affiliated with its authors. Original data and post content stay intact.', 'tocnest' ) . '</p>';
		/* translators: 1: Option groups, 2: Posts with overrides, 3: Posts with shortcodes. */
		echo '<p>' . esc_html( sprintf( __( 'Found %1$d option groups, %2$d posts with settings and %3$d posts with old shortcodes. Post counts are capped at 10,001 and cached for five minutes.', 'tocnest' ), count( $detected['options'] ), $detected['meta'], $detected['shortcodes'] ) ) . '</p>';
		self::action_form( 'tocnest_import', __( 'Import settings', 'tocnest' ) );
		if ( false !== get_option( 'tocnest_settings_backup', false ) ) {
			self::action_form( 'tocnest_undo', __( 'Undo import', 'tocnest' ) );
		}
		$report = get_option( 'tocnest_import_report', array() );
		if ( $report ) {
			echo '<h3>' . esc_html__( 'Import report', 'tocnest' ) . '</h3><ul>';
			foreach ( $report as $message ) {
				echo '<li>' . esc_html( $message ) . '</li>';
			}
			echo '</ul>';
		}
		echo '<p>' . esc_html__( 'Per-post settings work immediately through lazy conversion. To save them permanently, run the optional batch conversion below. Each request processes up to 200 posts. Existing Tocnest overrides are preserved. Undo restores global settings only.', 'tocnest' ) . '</p><button type="button" id="tocnest-convert" class="button" data-nonce="' . esc_attr( wp_create_nonce( 'tocnest_convert' ) ) . '">' . esc_html__( 'Convert per-post settings now', 'tocnest' ) . '</button><p id="tocnest-progress" role="status" aria-live="polite"></p>';
	}

	/**
	 * Output a nonce-protected administrative action form.
	 *
	 * @param string $action Handler name.
	 * @param string $label Button label.
	 */
	private static function action_form( $action, $label ) {
		echo '<form class="tocnest-action" method="post" action="' . esc_url( admin_url( 'admin-post.php' ) ) . '"><input type="hidden" name="action" value="' . esc_attr( $action ) . '">';
		wp_nonce_field( $action );
		submit_button( $label, 'secondary', 'submit', false );
		echo '</form>';
	}

	/**
	 * Load only the migration progress script on this settings screen.
	 *
	 * @param string $hook Screen ID.
	 */
	public static function assets( $hook ) {
		if ( 'settings_page_tocnest' === $hook ) {
			wp_enqueue_style( 'tocnest-admin', TOCNEST_URL . 'assets/admin.css', array(), TOCNEST_VERSION );
			wp_enqueue_script( 'tocnest-admin', TOCNEST_URL . 'assets/admin.js', array( 'wp-i18n' ), TOCNEST_VERSION, true );
			wp_set_script_translations( 'tocnest-admin', 'tocnest', TOCNEST_PATH . 'languages' );
		}
	}

	/** Register a compatible meta box in both editors. */
	public static function metaboxes() {
		foreach ( Tocnest_Settings::get()['metabox_types'] as $type ) {
			add_meta_box( 'tocnest-settings', __( 'Tocnest', 'tocnest' ), array( __CLASS__, 'metabox' ), $type, 'side', 'default', array( '__block_editor_compatible_meta_box' => true ) );
		}
	}

	/**
	 * Render per-post controls.
	 *
	 * @param WP_Post $post Current post.
	 */
	public static function metabox( $post ) {
		$settings = Tocnest_Settings::post_overrides( $post->ID );
		wp_nonce_field( 'tocnest_meta', 'tocnest_meta_nonce' );
		echo '<p><label for="tocnest-enabled">' . esc_html__( 'TOC on this post', 'tocnest' ) . '</label><br><select id="tocnest-enabled" name="tocnest_meta[enabled]">';
		foreach ( array(
			''  => __( 'Use global setting', 'tocnest' ),
			'1' => __( 'Enable', 'tocnest' ),
			'0' => __( 'Disable', 'tocnest' ),
		) as $value => $label ) {
			$current = isset( $settings['enabled'] ) ? (string) (int) $settings['enabled'] : '';
			echo '<option value="' . esc_attr( $value ) . '" ' . selected( $current, (string) $value, false ) . '>' . esc_html( $label ) . '</option>';
		}
		echo '</select></p><p><label for="tocnest-position">' . esc_html__( 'Position', 'tocnest' ) . '</label><br><select id="tocnest-position" name="tocnest_meta[position]"><option value="">' . esc_html__( 'Use global setting', 'tocnest' ) . '</option>';
		$labels = self::choices();
		foreach ( Tocnest_Settings::enums()['position'] as $value ) {
			echo '<option value="' . esc_attr( $value ) . '" ' . selected( isset( $settings['position'] ) ? $settings['position'] : '', $value, false ) . '>' . esc_html( $labels[ $value ] ) . '</option>';
		}
		echo '</select></p><p><label for="tocnest-min">' . esc_html__( 'Minimum headings (blank inherits)', 'tocnest' ) . '</label><br><input id="tocnest-min" type="number" min="1" max="999" name="tocnest_meta[min]" value="' . esc_attr( isset( $settings['min'] ) ? $settings['min'] : '' ) . '"></p>';
	}

	/**
	 * Save overrides only after nonce, autosave and edit capability checks.
	 *
	 * @param int $post_id Post ID.
	 */
	public static function save_meta( $post_id ) {
		if ( ! isset( $_POST['tocnest_meta_nonce'] ) || ! wp_verify_nonce( sanitize_text_field( wp_unslash( $_POST['tocnest_meta_nonce'] ) ), 'tocnest_meta' ) || ! current_user_can( 'edit_post', $post_id ) || wp_is_post_autosave( $post_id ) || wp_is_post_revision( $post_id ) ) {
			return;
		}
		$raw      = isset( $_POST['tocnest_meta'] ) && is_array( $_POST['tocnest_meta'] ) ? wp_unslash( $_POST['tocnest_meta'] ) : array(); // phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized -- Validated through the shared schema below.
		$raw      = array_filter(
			$raw,
			static function ( $value ) {
				return '' !== $value;
			}
		);
		$existing = Tocnest_Settings::post_overrides( $post_id );
		foreach ( array( 'enabled', 'position', 'min' ) as $key ) {
			unset( $existing[ $key ] );
		}
		update_post_meta( $post_id, '_tocnest_settings', array_merge( $existing, Tocnest_Settings::sanitize_meta( array_intersect_key( $raw, array_flip( array( 'enabled', 'position', 'min' ) ) ) ) ) );
	}

	/** Reset global settings without touching posts or source plugin data. */
	public static function reset() {
		if ( ! current_user_can( 'manage_options' ) ) {
			wp_die( esc_html__( 'You cannot manage Tocnest settings.', 'tocnest' ), '', array( 'response' => 403 ) );
		}
		check_admin_referer( 'tocnest_reset' );
		delete_option( 'tocnest_settings' );
		wp_safe_redirect( admin_url( 'options-general.php?page=tocnest' ) );
		exit;
	}
}