<?php
/**
 * Settings model.
 *
 * @package MM_Post_Grid
 */

namespace MM_Post_Grid;

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

/**
 * Owns the plugin option: schema, defaults, reads and sanitization.
 *
 * The schema holds data types only, no translated strings, so that reading a
 * setting on the front end never triggers translation loading. Labels and help
 * text live in the admin layer.
 *
 * @since 0.1
 */
final class Settings {

	/**
	 * Option name. All settings live in this single row.
	 *
	 * @since 0.1
	 * @var string
	 */
	const OPTION = 'mmpg_settings';

	/**
	 * Settings group used by the Settings API.
	 *
	 * @since 0.1
	 * @var string
	 */
	const GROUP = 'mmpg_settings_group';

	/**
	 * Runtime cache for the merged settings.
	 *
	 * @since 0.1
	 * @var array<string, mixed>|null
	 */
	private static $settings = null;

	/**
	 * Runtime cache for the defaults.
	 *
	 * @since 0.1
	 * @var array<string, mixed>|null
	 */
	private static $defaults = null;

	/**
	 * Returns the setting schema.
	 *
	 * Each entry supports: `type`, `default`, `min`, `max`, `step` and `choices`.
	 *
	 * @since 0.1
	 * @return array<string, array<string, mixed>>
	 */
	public static function schema() {
		$schema = array(
			// Query.
			'post_type'           => array(
				'type'    => 'post_type',
				'default' => 'post',
			),
			'posts_per_page'      => array(
				'type'    => 'int',
				'default' => 6,
				'min'     => 1,
				'max'     => 48,
			),
			'orderby'             => array(
				'type'    => 'choice',
				'default' => 'date',
				'choices' => array( 'date', 'modified', 'title', 'menu_order', 'comment_count', 'rand', 'ID' ),
			),
			'order'               => array(
				'type'    => 'choice',
				'default' => 'DESC',
				'choices' => array( 'ASC', 'DESC' ),
			),
			'pagination'          => array(
				'type'    => 'choice',
				'default' => 'none',
				'choices' => array( 'none', 'numbers', 'prev_next', 'load_more' ),
			),

			// Layout.
			'columns'             => array(
				'type'    => 'int',
				'default' => 3,
				'min'     => 1,
				'max'     => 6,
			),
			'columns_tablet'      => array(
				'type'    => 'int',
				'default' => 2,
				'min'     => 1,
				'max'     => 4,
			),
			'columns_mobile'      => array(
				'type'    => 'int',
				'default' => 1,
				'min'     => 1,
				'max'     => 2,
			),
			'gap'                 => array(
				'type'    => 'int',
				'default' => 28,
				'min'     => 0,
				'max'     => 80,
			),
			'image_size'          => array(
				'type'    => 'image_size',
				'default' => 'large',
			),
			'image_ratio'         => array(
				'type'    => 'choice',
				'default' => '16-10',
				'choices' => array( '16-9', '16-10', '3-2', '4-3', '1-1', '3-4', 'auto' ),
			),

			// Card elements.
			'show_image'          => array(
				'type'    => 'bool',
				'default' => 1,
			),
			'image_fallback'      => array(
				'type'    => 'bool',
				'default' => 1,
			),
			'show_category'       => array(
				'type'    => 'bool',
				'default' => 1,
			),
			'show_title'          => array(
				'type'    => 'bool',
				'default' => 1,
			),
			'show_excerpt'        => array(
				'type'    => 'bool',
				'default' => 1,
			),
			'show_date'           => array(
				'type'    => 'bool',
				'default' => 1,
			),
			'show_author'         => array(
				'type'    => 'bool',
				'default' => 0,
			),
			'show_read_more'      => array(
				'type'    => 'bool',
				'default' => 1,
			),

			// Card text.
			'title_tag'           => array(
				'type'    => 'choice',
				'default' => 'h3',
				'choices' => array( 'h2', 'h3', 'h4', 'h5', 'h6', 'p', 'div' ),
			),
			'excerpt_length'      => array(
				'type'    => 'int',
				'default' => 20,
				'min'     => 0,
				'max'     => 100,
			),
			'read_more_text'      => array(
				'type'    => 'text',
				'default' => 'Read more',
			),

			// Card styling.
			'card_layout'         => array(
				'type'    => 'choice',
				'default' => 'stacked',
				'choices' => array( 'stacked', 'horizontal', 'overlay' ),
			),
			'card_bg'             => array(
				'type'        => 'color',
				'default'     => '#ffffff',
				'allow_empty' => true,
			),
			'card_border_color'   => array(
				'type'    => 'color',
				'default' => '#e6e6ef',
			),
			'card_border_width'   => array(
				'type'    => 'int',
				'default' => 1,
				'min'     => 0,
				'max'     => 4,
			),
			'card_radius'         => array(
				'type'    => 'int',
				'default' => 14,
				'min'     => 0,
				'max'     => 40,
			),
			'card_padding'        => array(
				'type'    => 'int',
				'default' => 22,
				'min'     => 0,
				'max'     => 48,
			),
			'card_shadow'         => array(
				'type'    => 'choice',
				'default' => 'soft',
				'choices' => array( 'none', 'soft', 'medium', 'strong' ),
			),
			'hover_effect'        => array(
				'type'    => 'choice',
				'default' => 'lift',
				'choices' => array( 'lift', 'shadow', 'border', 'none' ),
			),
			'card_border_hover'   => array(
				'type'        => 'color',
				'default'     => '',
				'allow_empty' => true,
			),
			'text_align'          => array(
				'type'    => 'choice',
				'default' => 'left',
				'choices' => array( 'left', 'center' ),
			),
			'content_gap'         => array(
				'type'    => 'int',
				'default' => 10,
				'min'     => 0,
				'max'     => 32,
			),

			// Image styling.
			'image_radius'        => array(
				'type'    => 'int',
				'default' => 0,
				'min'     => 0,
				'max'     => 40,
			),
			'image_hover'         => array(
				'type'    => 'choice',
				'default' => 'zoom',
				'choices' => array( 'zoom', 'none', 'grayscale' ),
			),
			'media_width'         => array(
				'type'    => 'int',
				'default' => 40,
				'min'     => 25,
				'max'     => 60,
			),
			'overlay_opacity'     => array(
				'type'    => 'int',
				'default' => 70,
				'min'     => 50,
				'max'     => 95,
			),

			// Typography and colours.
			'title_color'         => array(
				'type'    => 'color',
				'default' => '#17172b',
			),
			'title_hover_color'   => array(
				'type'    => 'color',
				'default' => '#4f46e5',
			),
			'title_size'          => array(
				'type'    => 'int',
				'default' => 19,
				'min'     => 12,
				'max'     => 40,
			),
			'title_weight'        => array(
				'type'    => 'choice',
				'default' => '600',
				'choices' => array( '400', '500', '600', '700', '800' ),
			),
			'title_line_height'   => array(
				'type'    => 'int',
				'default' => 135,
				'min'     => 100,
				'max'     => 200,
			),
			'title_lines'         => array(
				'type'    => 'int',
				'default' => 0,
				'min'     => 0,
				'max'     => 5,
			),
			'meta_color'          => array(
				'type'    => 'color',
				'default' => '#6b6b80',
			),
			'meta_size'           => array(
				'type'    => 'int',
				'default' => 13,
				'min'     => 10,
				'max'     => 20,
			),
			'excerpt_color'       => array(
				'type'    => 'color',
				'default' => '#4a4a5f',
			),
			'excerpt_size'        => array(
				'type'    => 'int',
				'default' => 15,
				'min'     => 12,
				'max'     => 24,
			),
			'excerpt_line_height' => array(
				'type'    => 'int',
				'default' => 160,
				'min'     => 120,
				'max'     => 220,
			),
			'excerpt_lines'       => array(
				'type'    => 'int',
				'default' => 0,
				'min'     => 0,
				'max'     => 8,
			),

			// Category labels.
			'term_style'          => array(
				'type'    => 'choice',
				'default' => 'text',
				'choices' => array( 'text', 'badge' ),
			),
			'term_color'          => array(
				'type'        => 'color',
				'default'     => '',
				'allow_empty' => true,
			),

			// Links and read more.
			'accent_color'        => array(
				'type'    => 'color',
				'default' => '#4f46e5',
			),
			'button_style'        => array(
				'type'    => 'choice',
				'default' => 'link',
				'choices' => array( 'link', 'button', 'outline' ),
			),
			'button_size'         => array(
				'type'    => 'choice',
				'default' => 'medium',
				'choices' => array( 'small', 'medium', 'large' ),
			),
			'button_bg'           => array(
				'type'    => 'color',
				'default' => '#4f46e5',
			),
			'button_bg_hover'     => array(
				'type'    => 'color',
				'default' => '#4338ca',
			),
			'button_color'        => array(
				'type'    => 'color',
				'default' => '#ffffff',
			),
			'button_radius'       => array(
				'type'    => 'int',
				'default' => 8,
				'min'     => 0,
				'max'     => 40,
			),
			'pagination_align'    => array(
				'type'    => 'choice',
				'default' => 'center',
				'choices' => array( 'left', 'center', 'right' ),
			),

			// Advanced.
			'disable_css'         => array(
				'type'    => 'bool',
				'default' => 0,
			),
			'delete_data'         => array(
				'type'    => 'bool',
				'default' => 0,
			),
		);

		/**
		 * Filters the setting schema.
		 *
		 * Use this to add a setting (types: bool, int, text, color, choice,
		 * post_type, image_size). Added keys are sanitized like core ones. A
		 * colour field may set 'allow_empty' => true to accept an empty value.
		 *
		 * @since 0.1
		 *
		 * @param array<string, array<string, mixed>> $schema Setting schema.
		 */
		return apply_filters( 'mmpg_settings_schema', $schema );
	}

	/**
	 * Returns the default value for every setting.
	 *
	 * @since 0.1
	 * @return array<string, mixed>
	 */
	public static function defaults() {
		if ( null !== self::$defaults ) {
			return self::$defaults;
		}

		$defaults = array();

		foreach ( self::schema() as $key => $field ) {
			$defaults[ $key ] = isset( $field['default'] ) ? $field['default'] : '';
		}

		self::$defaults = $defaults;

		return self::$defaults;
	}

	/**
	 * Returns all settings, stored values merged over the defaults.
	 *
	 * @since 0.1
	 * @return array<string, mixed>
	 */
	public static function all() {
		if ( null !== self::$settings ) {
			return self::$settings;
		}

		$stored   = get_option( self::OPTION, array() );
		$stored   = is_array( $stored ) ? $stored : array();
		$defaults = self::defaults();

		self::$settings = array_merge( $defaults, array_intersect_key( $stored, $defaults ) );

		return self::$settings;
	}

	/**
	 * Returns a single setting.
	 *
	 * @since 0.1
	 *
	 * @param string $key Setting key.
	 * @return mixed Setting value, or null when the key is unknown.
	 */
	public static function get( $key ) {
		$settings = self::all();

		return array_key_exists( $key, $settings ) ? $settings[ $key ] : null;
	}

	/**
	 * Clears the runtime cache.
	 *
	 * @since 0.1
	 * @return void
	 */
	public static function flush_cache() {
		self::$settings = null;
		self::$defaults = null;
	}

	/**
	 * Sanitizes the submitted settings.
	 *
	 * Only the keys present in the request are touched, so saving one tab never
	 * wipes the values of another. Unchecked checkboxes are still submitted as
	 * `0` through a paired hidden input.
	 *
	 * @since 0.1
	 *
	 * @param mixed $input Raw `$_POST` value for the option.
	 * @return array<string, mixed>
	 */
	public static function sanitize( $input ) {
		$current = self::all();

		if ( ! is_array( $input ) ) {
			return $current;
		}

		$output = $current;

		foreach ( self::schema() as $key => $field ) {
			if ( ! array_key_exists( $key, $input ) ) {
				continue;
			}

			$output[ $key ] = self::sanitize_value( $input[ $key ], $field );
		}

		// The cache is deliberately NOT primed here. This runs as the
		// sanitize_option callback, before anything is persisted, so if the
		// write is vetoed or fails the rest of the request would read values
		// that were never saved. Plugin::init() flushes the cache on
		// update_option_mmpg_settings instead, once the save is real.
		return $output;
	}

	/**
	 * Sanitizes one value against its schema entry.
	 *
	 * @since 0.1
	 *
	 * @param mixed                $value Raw value.
	 * @param array<string, mixed> $field Schema entry.
	 * @return mixed
	 */
	public static function sanitize_value( $value, array $field ) {
		$type    = isset( $field['type'] ) ? $field['type'] : 'text';
		$default = isset( $field['default'] ) ? $field['default'] : '';

		switch ( $type ) {
			case 'bool':
				return Helpers::to_bool( $value ) ? 1 : 0;

			case 'int':
				$min = isset( $field['min'] ) ? $field['min'] : 0;
				$max = isset( $field['max'] ) ? $field['max'] : 9999;

				return is_numeric( $value ) ? Helpers::clamp_int( $value, $min, $max ) : $default;

			case 'color':
				$raw = is_string( $value ) ? trim( $value ) : '';

				// Some colours may be left empty on purpose: a transparent card,
				// or a category colour that simply follows the accent colour.
				if ( '' === $raw && ! empty( $field['allow_empty'] ) ) {
					return '';
				}

				$color = sanitize_hex_color( $raw );

				return $color ? $color : $default;

			case 'choice':
				$choices = isset( $field['choices'] ) ? array_map( 'strval', (array) $field['choices'] ) : array();
				$value   = is_scalar( $value ) ? (string) $value : '';

				// Compared as strings, so 700 and '700' are the same choice
				// whether they come from a form, a shortcode or a filter.
				return in_array( $value, $choices, true ) ? $value : $default;

			case 'post_type':
				$post_type = sanitize_key( $value );

				return post_type_exists( $post_type ) && is_post_type_viewable( $post_type ) ? $post_type : $default;

			case 'image_size':
				$size = sanitize_key( $value );

				return in_array( $size, self::image_sizes(), true ) ? $size : $default;

			case 'text':
			default:
				return sanitize_text_field( (string) $value );
		}
	}

	/**
	 * Returns the registered image size names, including `full`.
	 *
	 * @since 0.1
	 * @return string[]
	 */
	public static function image_sizes() {
		$sizes = get_intermediate_image_sizes();
		$sizes = is_array( $sizes ) ? $sizes : array();

		$sizes[] = 'full';

		return array_values( array_unique( $sizes ) );
	}
}