<?php
/**
 * Plugin settings.
 *
 * @package Blocksy_Light_Dark_Toggle
 */

defined( 'ABSPATH' ) || exit;

/**
 * Settings registration and helpers.
 */
class BLC_LDT_Settings {

	const OPTION = 'blc_ldt_settings';

	/**
	 * Default settings.
	 *
	 * @return array<string, mixed>
	 */
	public static function defaults() {
		return array(
			'position'              => 'bottom-right',
			'offset_x'              => '1.25rem',
			'offset_y'              => '1.25rem',
			'z_index'               => 999999,
			'hide_header_switch'    => true,
			'respect_os_preference' => true,
			'enable_animation'      => true,
			'show_on_mobile'        => true,
			'show_on_desktop'       => true,
		);
	}

	/**
	 * Initialize admin settings.
	 */
	public static function init() {
		add_action( 'admin_init', array( __CLASS__, 'register' ) );
		add_action( 'admin_menu', array( __CLASS__, 'add_menu' ) );
		add_filter( 'plugin_action_links_' . plugin_basename( BLC_LDT_FILE ), array( __CLASS__, 'plugin_links' ) );
	}

	/**
	 * Get merged settings.
	 *
	 * @return array<string, mixed>
	 */
	public static function get() {
		$stored = get_option( self::OPTION, array() );
		if ( ! is_array( $stored ) ) {
			$stored = array();
		}

		$settings = wp_parse_args( $stored, self::defaults() );

		return apply_filters( 'blc_ldt_settings', $settings );
	}

	/**
	 * Get a single setting.
	 *
	 * @param string $key Setting key.
	 * @return mixed
	 */
	public static function get_value( $key ) {
		$settings = self::get();
		return isset( $settings[ $key ] ) ? $settings[ $key ] : null;
	}

	/**
	 * Register settings with the Settings API.
	 */
	public static function register() {
		register_setting(
			'blc_ldt_settings_group',
			self::OPTION,
			array(
				'type'              => 'array',
				'sanitize_callback' => array( __CLASS__, 'sanitize' ),
				'default'           => self::defaults(),
			)
		);

		add_settings_section(
			'blc_ldt_main',
			__( 'Toggle appearance', 'blocksy-light-dark-toggle' ),
			'__return_false',
			'blc-ldt-settings'
		);

		self::add_field( 'position', __( 'Position', 'blocksy-light-dark-toggle' ), array( __CLASS__, 'field_position' ) );
		self::add_field( 'offset_x', __( 'Horizontal offset', 'blocksy-light-dark-toggle' ), array( __CLASS__, 'field_offset_x' ) );
		self::add_field( 'offset_y', __( 'Vertical offset', 'blocksy-light-dark-toggle' ), array( __CLASS__, 'field_offset_y' ) );
		self::add_field( 'z_index', __( 'Z-index', 'blocksy-light-dark-toggle' ), array( __CLASS__, 'field_z_index' ) );

		add_settings_section(
			'blc_ldt_behavior',
			__( 'Behavior', 'blocksy-light-dark-toggle' ),
			array( __CLASS__, 'section_behavior' ),
			'blc-ldt-settings'
		);

		self::add_field( 'hide_header_switch', __( 'Hide header colour switch', 'blocksy-light-dark-toggle' ), array( __CLASS__, 'field_hide_header_switch' ), 'blc_ldt_behavior' );
		self::add_field( 'respect_os_preference', __( 'Follow system preference', 'blocksy-light-dark-toggle' ), array( __CLASS__, 'field_respect_os_preference' ), 'blc_ldt_behavior' );
		self::add_field( 'enable_animation', __( 'Animate transitions', 'blocksy-light-dark-toggle' ), array( __CLASS__, 'field_enable_animation' ), 'blc_ldt_behavior' );
		self::add_field( 'show_on_mobile', __( 'Show on mobile', 'blocksy-light-dark-toggle' ), array( __CLASS__, 'field_show_on_mobile' ), 'blc_ldt_behavior' );
		self::add_field( 'show_on_desktop', __( 'Show on desktop', 'blocksy-light-dark-toggle' ), array( __CLASS__, 'field_show_on_desktop' ), 'blc_ldt_behavior' );
	}

	/**
	 * Register a settings field.
	 *
	 * @param string   $id       Field ID.
	 * @param string   $title    Field title.
	 * @param callable $callback Render callback.
	 * @param string   $section  Settings section.
	 */
	private static function add_field( $id, $title, $callback, $section = 'blc_ldt_main' ) {
		add_settings_field(
			'blc_ldt_' . $id,
			$title,
			$callback,
			'blc-ldt-settings',
			$section,
			array( 'id' => $id )
		);
	}

	/**
	 * Sanitize submitted settings.
	 *
	 * @param array<string, mixed> $input Raw input.
	 * @return array<string, mixed>
	 */
	public static function sanitize( $input ) {
		$defaults = self::defaults();
		$output   = self::defaults();

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

		$positions = array( 'bottom-right', 'bottom-left', 'top-right', 'top-left' );
		$output['position'] = in_array( $input['position'] ?? '', $positions, true )
			? $input['position']
			: $defaults['position'];

		$output['offset_x'] = self::sanitize_css_length( $input['offset_x'] ?? $defaults['offset_x'], $defaults['offset_x'] );
		$output['offset_y'] = self::sanitize_css_length( $input['offset_y'] ?? $defaults['offset_y'], $defaults['offset_y'] );
		$output['z_index']  = max( 1, min( 9999999, absint( $input['z_index'] ?? $defaults['z_index'] ) ) );

		$output['hide_header_switch']    = ! empty( $input['hide_header_switch'] );
		$output['respect_os_preference'] = ! empty( $input['respect_os_preference'] );
		$output['enable_animation']      = ! empty( $input['enable_animation'] );
		$output['show_on_mobile']        = ! empty( $input['show_on_mobile'] );
		$output['show_on_desktop']       = ! empty( $input['show_on_desktop'] );

		return $output;
	}

	/**
	 * Sanitize a CSS length value.
	 *
	 * @param string $value   Raw value.
	 * @param string $default Default value.
	 * @return string
	 */
	private static function sanitize_css_length( $value, $default ) {
		$value = trim( (string) $value );
		if ( preg_match( '/^\d+(\.\d+)?(px|rem|em|vh|vw|%)$/', $value ) ) {
			return $value;
		}
		return $default;
	}

	/**
	 * Add settings page.
	 */
	public static function add_menu() {
		add_options_page(
			__( 'Light/Dark Toggle', 'blocksy-light-dark-toggle' ),
			__( 'Light/Dark Toggle', 'blocksy-light-dark-toggle' ),
			'manage_options',
			'blc-ldt-settings',
			array( __CLASS__, 'render_page' )
		);
	}

	/**
	 * Settings link on plugins list.
	 *
	 * @param string[] $links Plugin action links.
	 * @return string[]
	 */
	public static function plugin_links( $links ) {
		$links[] = '<a href="' . esc_url( admin_url( 'options-general.php?page=blc-ldt-settings' ) ) . '">' . esc_html__( 'Settings', 'blocksy-light-dark-toggle' ) . '</a>';
		return $links;
	}

	/**
	 * Behavior section description.
	 */
	public static function section_behavior() {
		echo '<p>' . esc_html__( 'These options control how the toggle interacts with Blocksy and visitor preferences.', 'blocksy-light-dark-toggle' ) . '</p>';
	}

	/**
	 * Render settings page.
	 */
	public static function render_page() {
		if ( ! current_user_can( 'manage_options' ) ) {
			return;
		}

		$has_color_mode = BLC_LDT::has_blocksy_color_mode();
		?>
		<div class="wrap">
			<h1><?php esc_html_e( 'Blocksy Light/Dark Toggle', 'blocksy-light-dark-toggle' ); ?></h1>

			<?php if ( ! BLC_LDT::is_target_theme() ) : ?>
				<div class="notice notice-warning"><p>
					<?php esc_html_e( 'Blocksy is not the active theme. The toggle only appears on the front end when Blocksy (or a child theme) is active.', 'blocksy-light-dark-toggle' ); ?>
				</p></div>
			<?php elseif ( ! $has_color_mode ) : ?>
				<div class="notice notice-info"><p>
					<?php
					echo wp_kses_post(
						__( 'For heavily customized sites, enable Blocksy\'s <strong>Colour Mode Switch</strong> extension and configure your dark palette in the Customizer. The plugin will then use your custom dark colors instead of the built-in fallback palette.', 'blocksy-light-dark-toggle' )
					);
					?>
				</p></div>
			<?php else : ?>
				<div class="notice notice-success"><p>
					<?php esc_html_e( 'Blocksy Colour Mode Switch is active. Your Customizer dark palette will be used.', 'blocksy-light-dark-toggle' ); ?>
				</p></div>
			<?php endif; ?>

			<form method="post" action="options.php">
				<?php
				settings_fields( 'blc_ldt_settings_group' );
				do_settings_sections( 'blc-ldt-settings' );
				submit_button();
				?>
			</form>
		</div>
		<?php
	}

	/**
	 * Read a checkbox value from settings.
	 *
	 * @param string $id Setting ID.
	 * @return bool
	 */
	private static function is_checked( $id ) {
		return (bool) self::get_value( $id );
	}

	/**
	 * Render position field.
	 */
	public static function field_position() {
		$value = self::get_value( 'position' );
		$options = array(
			'bottom-right' => __( 'Bottom right', 'blocksy-light-dark-toggle' ),
			'bottom-left'  => __( 'Bottom left', 'blocksy-light-dark-toggle' ),
			'top-right'    => __( 'Top right', 'blocksy-light-dark-toggle' ),
			'top-left'     => __( 'Top left', 'blocksy-light-dark-toggle' ),
		);
		?>
		<select name="<?php echo esc_attr( self::OPTION ); ?>[position]">
			<?php foreach ( $options as $key => $label ) : ?>
				<option value="<?php echo esc_attr( $key ); ?>" <?php selected( $value, $key ); ?>><?php echo esc_html( $label ); ?></option>
			<?php endforeach; ?>
		</select>
		<?php
	}

	/**
	 * Render horizontal offset field.
	 */
	public static function field_offset_x() {
		?>
		<input type="text" class="small-text" name="<?php echo esc_attr( self::OPTION ); ?>[offset_x]" value="<?php echo esc_attr( (string) self::get_value( 'offset_x' ) ); ?>">
		<p class="description"><?php esc_html_e( 'CSS value, e.g. 1.25rem or 20px', 'blocksy-light-dark-toggle' ); ?></p>
		<?php
	}

	/**
	 * Render vertical offset field.
	 */
	public static function field_offset_y() {
		?>
		<input type="text" class="small-text" name="<?php echo esc_attr( self::OPTION ); ?>[offset_y]" value="<?php echo esc_attr( (string) self::get_value( 'offset_y' ) ); ?>">
		<p class="description"><?php esc_html_e( 'CSS value, e.g. 1.25rem or 20px', 'blocksy-light-dark-toggle' ); ?></p>
		<?php
	}

	/**
	 * Render z-index field.
	 */
	public static function field_z_index() {
		?>
		<input type="number" class="small-text" min="1" max="9999999" name="<?php echo esc_attr( self::OPTION ); ?>[z_index]" value="<?php echo esc_attr( (string) self::get_value( 'z_index' ) ); ?>">
		<?php
	}

	/**
	 * Render hide header switch field.
	 */
	public static function field_hide_header_switch() {
		?>
		<label>
			<input type="checkbox" name="<?php echo esc_attr( self::OPTION ); ?>[hide_header_switch]" value="1" <?php checked( self::is_checked( 'hide_header_switch' ) ); ?>>
			<?php esc_html_e( 'Hide Blocksy header colour switch to avoid duplicate toggles', 'blocksy-light-dark-toggle' ); ?>
		</label>
		<?php
	}

	/**
	 * Render respect OS preference field.
	 */
	public static function field_respect_os_preference() {
		?>
		<label>
			<input type="checkbox" name="<?php echo esc_attr( self::OPTION ); ?>[respect_os_preference]" value="1" <?php checked( self::is_checked( 'respect_os_preference' ) ); ?>>
			<?php esc_html_e( 'Use system light/dark preference on first visit (before the visitor toggles)', 'blocksy-light-dark-toggle' ); ?>
		</label>
		<?php
	}

	/**
	 * Render animation field.
	 */
	public static function field_enable_animation() {
		?>
		<label>
			<input type="checkbox" name="<?php echo esc_attr( self::OPTION ); ?>[enable_animation]" value="1" <?php checked( self::is_checked( 'enable_animation' ) ); ?>>
			<?php esc_html_e( 'Smooth colour transition when switching modes', 'blocksy-light-dark-toggle' ); ?>
		</label>
		<?php
	}

	/**
	 * Render show on mobile field.
	 */
	public static function field_show_on_mobile() {
		?>
		<label>
			<input type="checkbox" name="<?php echo esc_attr( self::OPTION ); ?>[show_on_mobile]" value="1" <?php checked( self::is_checked( 'show_on_mobile' ) ); ?>>
			<?php esc_html_e( 'Show the floating toggle on mobile screens', 'blocksy-light-dark-toggle' ); ?>
		</label>
		<?php
	}

	/**
	 * Render show on desktop field.
	 */
	public static function field_show_on_desktop() {
		?>
		<label>
			<input type="checkbox" name="<?php echo esc_attr( self::OPTION ); ?>[show_on_desktop]" value="1" <?php checked( self::is_checked( 'show_on_desktop' ) ); ?>>
			<?php esc_html_e( 'Show the floating toggle on desktop screens', 'blocksy-light-dark-toggle' ); ?>
		</label>
		<?php
	}
}