<?php
/**
 * Settings schema and validation.
 *
 * @package Tocnest
 */

defined( 'ABSPATH' ) || exit;

/** Validates all persisted and render-time settings. */
class Tocnest_Settings {
	/**
	 * Get factory settings.
	 *
	 * @return array
	 */
	public static function defaults() {
		return array(
			'title'             => __( 'Contents', 'tocnest' ),
			'show_title'        => true,
			'title_tag'         => 'p',
			'toggle'            => true,
			'label_show'        => __( 'Show', 'tocnest' ),
			'label_hide'        => __( 'Hide', 'tocnest' ),
			'collapsed'         => false,
			'min'               => 3,
			'depth'             => 6,
			'levels'            => array( 2, 3, 4 ),
			'hierarchical'      => true,
			'numbering'         => 'decimalnested',
			'suffix'            => 'none',
			'skip_levels'       => '',
			'skip_text'         => '',
			'skip_class'        => '',
			'anchor_format'     => 'text',
			'lowercase'         => true,
			'dashes'            => true,
			'smooth'            => true,
			'offset'            => 24,
			'highlight'         => false,
			'scheme'            => 'light',
			'background'        => '',
			'border'            => '',
			'title_color'       => '',
			'link'              => '',
			'hover'             => '',
			'visited'           => '',
			'width'             => 'auto',
			'float'             => 'none',
			'title_size'        => '1.1em',
			'title_weight'      => '700',
			'items_size'        => '1em',
			'markup'            => 'ol',
			'class'             => '',
			'nofollow'          => false,
			'auto'              => true,
			'post_types'        => array( 'post' ),
			'anchor_types'      => array(),
			'metabox_types'     => array( 'post', 'page' ),
			'position'          => 'beforefirstheading',
			'compat'            => false,
			'override_previous' => false,
		);
	}

	/**
	 * Enumerated values accepted by settings.
	 *
	 * @return array
	 */
	public static function enums() {
		return array(
			'title_tag'     => array( 'p', 'div' ),
			'numbering'     => array( 'none', 'decimal', 'decimalnested', 'roman', 'romannested' ),
			'suffix'        => array( 'none', 'dot', 'roundbracket' ),
			'anchor_format' => array( 'text', 'text_raw', 'counter' ),
			'scheme'        => array( 'light', 'dark', 'white', 'transparent', 'inherit' ),
			'float'         => array( 'none', 'left', 'right', 'center' ),
			'title_weight'  => array( '100', '200', '300', '400', '500', '600', '700', '800', '900' ),
			'markup'        => array( 'ol', 'ul' ),
			'position'      => array( 'beforefirstheading', 'afterfirstheading', 'afterfirstblock', 'top', 'bottom' ),
		);
	}

	/**
	 * Convert HTML and shortcode booleans consistently.
	 *
	 * @param mixed $value Raw value.
	 * @return bool
	 */
	public static function boolean( $value ) {
		return in_array( $value, array( true, 1, '1', 'true', 'on', 'yes' ), true );
	}

	/**
	 * Validate a safe CSS length without functions or declarations.
	 *
	 * @param string $value CSS length.
	 * @param string $fallback Default length.
	 * @return string
	 */
	public static function length( $value, $fallback = 'auto' ) {
		return is_scalar( $value ) && preg_match( '/^(?:0|(?:\d*\.)?\d+(?:px|em|rem|%|vw|vh|ch))$/i', (string) $value ) ? (string) $value : $fallback;
	}

	/**
	 * Validate settings. Partial mode keeps only explicitly provided keys.
	 *
	 * @param mixed $input Raw values.
	 * @param bool  $partial Whether to omit missing keys.
	 * @return array
	 */
	public static function sanitize( $input, $partial = false ) {
		$defaults = self::defaults();
		$enums    = self::enums();
		$output   = $partial ? array() : $defaults;
		foreach ( (array) $input as $key => $value ) {
			if ( ! array_key_exists( $key, $defaults ) || null === $value ) {
				continue;
			}
			$default = $defaults[ $key ];
			if ( is_bool( $default ) ) {
				$output[ $key ] = self::boolean( $value );
			} elseif ( isset( $enums[ $key ] ) ) {
				$output[ $key ] = in_array( $value, $enums[ $key ], true ) ? $value : $default;
			} elseif ( is_int( $default ) ) {
				$limits         = array(
					'min'    => array( 1, 999 ),
					'depth'  => array( 1, 6 ),
					'offset' => array( -1000, 2000 ),
				);
				$output[ $key ] = is_numeric( $value ) ? max( $limits[ $key ][0], min( $limits[ $key ][1], (int) $value ) ) : $default;
			} elseif ( is_array( $default ) ) {
				$values         = is_array( $value ) ? $value : ( is_scalar( $value ) ? explode( ',', (string) $value ) : $default );
				$values         = array_filter( $values, 'is_scalar' );
				$output[ $key ] = 'levels' === $key ? array_values( array_intersect( array( 1, 2, 3, 4, 5, 6 ), array_map( 'intval', $values ) ) ) : array_values( array_unique( array_filter( array_map( 'sanitize_key', $values ) ) ) );
			} elseif ( ! is_scalar( $value ) ) {
				$output[ $key ] = $default;
			} elseif ( in_array( $key, array( 'background', 'border', 'title_color', 'link', 'hover', 'visited' ), true ) ) {
				$output[ $key ] = sanitize_hex_color( $value ) ? sanitize_hex_color( $value ) : '';
			} elseif ( in_array( $key, array( 'width', 'title_size', 'items_size' ), true ) ) {
				$output[ $key ] = 'width' === $key && in_array( $value, array( 'auto', 'full' ), true ) ? $value : self::length( $value, $default );
			} elseif ( in_array( $key, array( 'class', 'skip_class' ), true ) ) {
				$output[ $key ] = implode( ' ', array_filter( array_map( 'sanitize_html_class', preg_split( '/\s+/', $value ) ) ) );
			} else {
				$output[ $key ] = 'skip_text' === $key ? sanitize_textarea_field( $value ) : sanitize_text_field( $value );
			}
		}
		foreach ( array( 'label_show', 'label_hide' ) as $key ) {
			if ( isset( $output[ $key ] ) && '' === $output[ $key ] ) {
				$output[ $key ] = $defaults[ $key ];
			}
		}
		return $output;
	}

	/**
	 * Read filtered global settings.
	 *
	 * @return array
	 */
	public static function get() {
		return self::sanitize( apply_filters( 'tocnest_settings', wp_parse_args( get_option( 'tocnest_settings', array() ), self::defaults() ) ) );
	}

	/**
	 * Get global settings with post overrides, including lazy migration.
	 *
	 * @param int $post_id Post ID.
	 * @return array
	 */
	public static function for_post( $post_id ) {
		return array_merge( self::get(), self::post_overrides( $post_id ) );
	}

	/**
	 * Read sparse overrides, including legacy values before conversion.
	 *
	 * @param int $post_id Post ID.
	 * @return array
	 */
	public static function post_overrides( $post_id ) {
		$meta = get_post_meta( $post_id, '_tocnest_settings', true );
		if ( ! metadata_exists( 'post', $post_id, '_tocnest_settings' ) && metadata_exists( 'post', $post_id, '_lwptoc_settings' ) ) {
			$meta = Tocnest_Migration::map( get_post_meta( $post_id, '_lwptoc_settings', true ), true )['settings'];
		}
		return self::sanitize_meta( $meta );
	}

	/**
	 * Validate post overrides, preserving inheritance through absent keys.
	 *
	 * @param mixed $input Raw meta.
	 * @return array
	 */
	public static function sanitize_meta( $input ) {
		$input  = is_array( $input ) ? $input : array();
		$output = self::sanitize( $input, true );
		foreach ( array( 'enabled', 'process_headings' ) as $key ) {
			if ( isset( $input[ $key ] ) && '' !== $input[ $key ] ) {
				$output[ $key ] = self::boolean( $input[ $key ] );
			}
		}
		return $output;
	}
}