<?php
/**
 * The feature registry: the single source of truth for every adjustment BirchToad offers.
 *
 * The visitor panel, the admin Features tab, the settings defaults and the JavaScript config all
 * read this one list, so a feature can never exist in one of them and be missing from another.
 *
 * @package BirchToad
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Feature registry.
 */
class BirchToad_Features {

	/**
	 * Built registry, cached per request.
	 *
	 * @var array|null
	 */
	private static $cache = null;

	/**
	 * Group keys in panel display order.
	 *
	 * @return string[]
	 */
	public static function groups() {
		return array( 'profiles', 'content', 'color', 'orientation' );
	}

	/**
	 * Translated group labels.
	 *
	 * Built on call, never at file load: reading a translation before init triggers the WordPress
	 * 6.7 "translation loaded too early" notice.
	 *
	 * @return array<string,array<string,string>>
	 */
	public static function group_labels() {
		return array(
			'profiles'    => array(
				'title' => __( 'Accessibility Features', 'birchtoad' ),
				'desc'  => __( 'Pick a profile that matches how you browse', 'birchtoad' ),
			),
			'content'     => array(
				'title' => __( 'Content Adjustments', 'birchtoad' ),
				'desc'  => __( 'Change how text looks and reads', 'birchtoad' ),
			),
			'color'       => array(
				'title' => __( 'Color Adjustments', 'birchtoad' ),
				'desc'  => __( 'Change contrast, saturation and colors', 'birchtoad' ),
			),
			'orientation' => array(
				'title' => __( 'Orientation Adjustments', 'birchtoad' ),
				'desc'  => __( 'Change navigation, motion and focus', 'birchtoad' ),
			),
		);
	}

	/**
	 * Every feature, keyed by its own key.
	 *
	 * Keys are permanent. A stored visitor choice and a saved site setting are both keyed on
	 * them, so renaming one silently discards what people already chose.
	 *
	 * Each entry carries:
	 * Paid features are NOT in this list. They are added by the __premium_only build through
	 * the birchtoad_features filter, so the free package does not contain their definitions,
	 * their labels or their keys at all. A paid feature defined here and hidden at runtime by
	 * a license check is the trialware shape WordPress.org guideline 5 rejects, however well
	 * the check works.
	 *
	 * Each entry carries:
	 *   group   string  one of self::groups()
	 *   type    string  toggle | range | choice | colorset | select
	 *   label   string  translated, shown to the visitor
	 *   order   int     position within its group
	 *   on      bool    whether a fresh install offers it to visitors
	 *   range   array   min, max, step, default (type range only)
	 *   choices array   value => label (type choice only)
	 *   exclusive bool  choosing one value releases the others (type choice)
	 *
	 * @return array<string,array>
	 */
	public static function all() {
		if ( null !== self::$cache ) {
			return self::$cache;
		}

		$features = array(

			// Profiles. Every one of these is a named bundle of the adjustments below and can do
			// nothing a visitor cannot do by hand.

			// Content.
			'content_scale'   => array(
				'group' => 'content',
				'order' => 10,
				'type'  => 'range',
				'label' => __( 'Content Scaling', 'birchtoad' ),
				'pro'   => false,
				'on'    => true,
				'range' => array(
					'min'     => 70,
					'max'     => 200,
					'step'    => 5,
					'default' => 100,
					'unit'    => '%',
				),
			),
			'font_size'       => array(
				'group' => 'content',
				'order' => 20,
				'type'  => 'range',
				'label' => __( 'Adjust Font Sizing', 'birchtoad' ),
				'pro'   => false,
				'on'    => true,
				'range' => array(
					'min'     => 70,
					'max'     => 200,
					'step'    => 5,
					'default' => 100,
					'unit'    => '%',
				),
			),
			'line_height'     => array(
				'group' => 'content',
				'order' => 30,
				'type'  => 'range',
				'label' => __( 'Adjust Line Height', 'birchtoad' ),
				'pro'   => false,
				'on'    => true,
				'range' => array(
					'min'     => 100,
					'max'     => 250,
					'step'    => 10,
					'default' => 100,
					'unit'    => '%',
				),
			),
			'letter_spacing'  => array(
				'group' => 'content',
				'order' => 40,
				'type'  => 'range',
				'label' => __( 'Adjust Letter Spacing', 'birchtoad' ),
				'pro'   => false,
				'on'    => true,
				'range' => array(
					'min'     => 0,
					'max'     => 10,
					'step'    => 1,
					'default' => 0,
					'unit'    => '',
				),
			),
			'word_spacing'    => array(
				'group' => 'content',
				'order' => 45,
				'type'  => 'range',
				'label' => __( 'Adjust Word Spacing', 'birchtoad' ),
				'pro'   => false,
				'on'    => true,
				'range' => array(
					'min'     => 0,
					'max'     => 10,
					'step'    => 1,
					'default' => 0,
					'unit'    => '',
				),
			),
			'readable_font'   => array(
				'group' => 'content',
				'order' => 50,
				'type'  => 'toggle',
				'label' => __( 'Readable Font', 'birchtoad' ),
				'pro'   => false,
				'on'    => true,
			),
			'highlight_titles' => array(
				'group' => 'content',
				'order' => 60,
				'type'  => 'toggle',
				'label' => __( 'Highlight Titles', 'birchtoad' ),
				'pro'   => false,
				'on'    => true,
			),
			'highlight_links' => array(
				'group' => 'content',
				'order' => 70,
				'type'  => 'toggle',
				'label' => __( 'Highlight Links', 'birchtoad' ),
				'pro'   => false,
				'on'    => true,
			),
			'text_align'      => array(
				'group'     => 'content',
				'order'     => 90,
				'type'      => 'choice',
				'label'     => __( 'Text Align', 'birchtoad' ),
				'pro'       => false,
				'on'        => true,
				'exclusive' => true,
				'default'   => 'none',
				'choices'   => array(
					'none'    => __( 'Site default', 'birchtoad' ),
					'left'    => __( 'Align Left', 'birchtoad' ),
					'center'  => __( 'Align Center', 'birchtoad' ),
					'right'   => __( 'Align Right', 'birchtoad' ),
					'justify' => __( 'Justify', 'birchtoad' ),
				),
			),

			// Color.
			'contrast_theme'  => array(
				'group'     => 'color',
				'order'     => 10,
				'type'      => 'choice',
				'label'     => __( 'Contrast Theme', 'birchtoad' ),
				'pro'       => false,
				'on'        => true,
				'exclusive' => true,
				'default'   => 'none',
				'choices'   => array(
					'none'  => __( 'Site default', 'birchtoad' ),
					'light' => __( 'Light Contrast', 'birchtoad' ),
					'dark'  => __( 'Dark Contrast', 'birchtoad' ),
				),
			),
			'high_contrast'   => array(
				'group' => 'color',
				'order' => 20,
				'type'  => 'toggle',
				'label' => __( 'High Contrast', 'birchtoad' ),
				'pro'   => false,
				'on'    => true,
			),
			'saturation'      => array(
				'group'     => 'color',
				'order'     => 30,
				'type'      => 'choice',
				'label'     => __( 'Saturation', 'birchtoad' ),
				'pro'       => false,
				'on'        => true,
				'exclusive' => true,
				'default'   => 'none',
				'choices'   => array(
					'none' => __( 'None', 'birchtoad' ),
					'high' => __( 'High', 'birchtoad' ),
					'low'  => __( 'Low', 'birchtoad' ),
					'mono' => __( 'Monochrome', 'birchtoad' ),
				),
			),

			// Orientation.
			'reading_guide'   => array(
				'group' => 'orientation',
				'order' => 30,
				'type'  => 'toggle',
				'label' => __( 'Reading Guide', 'birchtoad' ),
				'pro'   => false,
				'on'    => true,
			),
			'stop_animations' => array(
				'group' => 'orientation',
				'order' => 40,
				'type'  => 'toggle',
				'label' => __( 'Stop Animations', 'birchtoad' ),
				'pro'   => false,
				'on'    => true,
			),
			'highlight_hover' => array(
				'group' => 'orientation',
				'order' => 60,
				'type'  => 'toggle',
				'label' => __( 'Highlight Hover', 'birchtoad' ),
				'pro'   => false,
				'on'    => true,
			),
			'highlight_focus' => array(
				'group' => 'orientation',
				'order' => 70,
				'type'  => 'toggle',
				'label' => __( 'Highlight Focus', 'birchtoad' ),
				'pro'   => false,
				'on'    => true,
			),
			'hide_images'     => array(
				'group' => 'orientation',
				'order' => 80,
				'type'  => 'toggle',
				'label' => __( 'Hide Images', 'birchtoad' ),
				'pro'   => false,
				'on'    => true,
			),
			'cursor'          => array(
				'group'     => 'orientation',
				'order'     => 100,
				'type'      => 'choice',
				'label'     => __( 'Cursor', 'birchtoad' ),
				'pro'       => false,
				'on'        => true,
				'exclusive' => true,
				'default'   => 'none',
				'choices'   => array(
					'none'  => __( 'None', 'birchtoad' ),
					'white' => __( 'Big White Cursor', 'birchtoad' ),
					'black' => __( 'Big Black Cursor', 'birchtoad' ),
				),
			),
		);

		/**
		 * Filters the feature registry.
		 *
		 * This is how the paid build adds anything of its own without the core ever checking a
		 * license.
		 *
		 * @param array $features The registry.
		 */
		$features = apply_filters( 'birchtoad_features', $features );

		// Keep the panel's running order stable whatever order things were registered in.
		uasort(
			$features,
			function ( $a, $b ) {
				$groups = array_flip( self::groups() );
				$ga     = isset( $groups[ $a['group'] ] ) ? $groups[ $a['group'] ] : 99;
				$gb     = isset( $groups[ $b['group'] ] ) ? $groups[ $b['group'] ] : 99;

				if ( $ga !== $gb ) {
					return $ga - $gb;
				}

				$oa = isset( $a['order'] ) ? $a['order'] : 50;
				$ob = isset( $b['order'] ) ? $b['order'] : 50;

				return $oa - $ob;
			}
		);

		self::$cache = $features;

		return self::$cache;
	}

	/**
	 * The features this edition can run.
	 *
	 * Identical to all(), because a feature this edition cannot run is not in the registry in
	 * the first place. Kept as its own call so the intent stays readable at the call sites.
	 *
	 * @return array<string,array>
	 */
	public static function available() {
		return self::all();
	}

	/**
	 * One feature, or null.
	 *
	 * @param string $key Feature key.
	 * @return array|null
	 */
	public static function get( $key ) {
		$all = self::all();

		return isset( $all[ $key ] ) ? $all[ $key ] : null;
	}

	/**
	 * Clears the per-request cache. Used by the tests and after a settings import.
	 *
	 * @return void
	 */
	public static function flush() {
		self::$cache = null;
	}
}