<?php
/**
 * Settings handling: admin menu, Settings API registration,
 * sanitization and default values.
 */

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

class ABSD_Settings {

	const OPTION_KEY = ABSD_UM_OPTION_KEY;
	const NONCE_ACTION = 'absd_um_save_settings';
	const CAPABILITY  = 'manage_options';

	/**
	 * @var ABSD_Templates
	 */
	private $templates;

	/**
	 * Cached settings.
	 *
	 * @var array|null
	 */
	private $cache = null;

	public function __construct( ABSD_Templates $templates ) {
		$this->templates = $templates;
	}

	/**
	 * Hook admin-side functionality.
	 */
	public function init() {
		add_action( 'admin_menu', array( $this, 'register_menu' ) );
		add_action( 'admin_init', array( $this, 'maybe_handle_actions' ) );
		add_action( 'admin_enqueue_scripts', array( $this, 'enqueue_admin_assets' ) );
		add_action( 'wp_ajax_absd_um_preview', array( $this, 'ajax_preview' ) );
	}

	/**
	 * Default option values.
	 *
	 * @return array
	 */
	public static function get_defaults() {
		return array(
			'maintenance_mode'    => false,
			'template'            => 'template-1',
			'logo_id'             => 0,
			'background_id'       => 0,
			'overlay_opacity'     => 70,
			'heading'             => __( 'We\'ll be back soon!', 'absd-under-maintenance' ),
			'description'         => __( 'We are currently working on improving our website.', 'absd-under-maintenance' ),
			'small_text'          => __( 'Thank you for your patience.', 'absd-under-maintenance' ),
			'footer_text'         => sprintf(
				/* translators: %s: current year */
				__( '&copy; %s All rights reserved.', 'absd-under-maintenance' ),
				gmdate( 'Y' )
			),
			'show_icon'           => true,
			'icon'                => 'wrench',
			'icon_custom_id'      => 0,
			'retry_text'          => __( 'Please try again later.', 'absd-under-maintenance' ),
			'show_contact'        => false,
			'contact_text'        => '',
			'accent_color'        => '#c9a15a',
			'private_access'      => false,
			'private_token'       => '',
		);
	}

	/**
	 * Get current settings merged with defaults.
	 *
	 * @return array
	 */
	public function get_settings() {
		if ( null !== $this->cache ) {
			return $this->cache;
		}

		$saved = get_option( self::OPTION_KEY, array() );
		if ( ! is_array( $saved ) ) {
			$saved = array();
		}

		$this->cache = wp_parse_args( $saved, self::get_defaults() );

		return $this->cache;
	}

	/**
	 * Get a single setting value.
	 *
	 * @param string $key Setting key.
	 * @param mixed  $fallback Fallback if not set.
	 * @return mixed
	 */
	public function get( $key, $fallback = '' ) {
		$settings = $this->get_settings();
		return isset( $settings[ $key ] ) ? $settings[ $key ] : $fallback;
	}

	/**
	 * Update settings (merges with existing).
	 *
	 * @param array $new_values New values to merge in.
	 * @return void
	 */
	public function update( array $new_values ) {
		$settings     = $this->get_settings();
		$settings     = array_merge( $settings, $new_values );
		$this->cache  = $settings;
		update_option( self::OPTION_KEY, $settings );
	}

	/**
	 * Register the admin menu page.
	 */
	public function register_menu() {
		add_menu_page(
			__( 'ABSD Under Maintenance', 'absd-under-maintenance' ),
			__( 'Under Maintenance', 'absd-under-maintenance' ),
			self::CAPABILITY,
			'absd-under-maintenance',
			array( $this, 'render_settings_page' ),
			'dashicons-hammer',
			80
		);
	}

	/**
	 * Enqueue admin CSS/JS only on our settings page.
	 *
	 * @param string $hook Current admin page hook.
	 */
	public function enqueue_admin_assets( $hook ) {
		if ( 'toplevel_page_absd-under-maintenance' !== $hook ) {
			return;
		}

		wp_enqueue_media();
		wp_enqueue_style( 'wp-color-picker' );
		wp_enqueue_script( 'wp-color-picker' );

		wp_enqueue_style(
			'absd-um-admin',
			ABSD_UM_URL . 'admin/css/admin.css',
			array( 'wp-color-picker' ),
			ABSD_UM_VERSION
		);

		wp_enqueue_script(
			'absd-um-admin',
			ABSD_UM_URL . 'admin/js/admin.js',
			array( 'jquery', 'wp-color-picker' ),
			ABSD_UM_VERSION,
			true
		);

		wp_localize_script(
			'absd-um-admin',
			'absdUmAdmin',
			array(
				'chooseLogo'       => __( 'Choose Logo', 'absd-under-maintenance' ),
				'chooseBackground' => __( 'Choose Background Image', 'absd-under-maintenance' ),
				'useImage'         => __( 'Use this image', 'absd-under-maintenance' ),
				'copied'           => __( 'Copied!', 'absd-under-maintenance' ),
				'ajaxUrl'          => admin_url( 'admin-ajax.php' ),
			)
		);
	}

	/**
	 * Handle form submissions (save settings, regenerate token, revoke token).
	 * Hooked on admin_init so redirects can still happen.
	 */
	public function maybe_handle_actions() {
		// admin_init also fires during admin-ajax.php requests (including
		// our own live-preview endpoint below, which serializes this same
		// form and so always carries absd_um_action=save_settings). The
		// real save/regenerate/revoke actions only ever arrive via a normal
		// full-page form POST, never AJAX — bail here so an AJAX request
		// can never be misread as a settings save.
		if ( wp_doing_ajax() ) {
			return;
		}

		if ( ! isset( $_POST['absd_um_action'] ) ) {
			return;
		}

		if ( ! current_user_can( self::CAPABILITY ) ) {
			wp_die( esc_html__( 'You do not have permission to perform this action.', 'absd-under-maintenance' ) );
		}

		if ( ! isset( $_POST['absd_um_nonce'] ) || ! wp_verify_nonce( sanitize_text_field( wp_unslash( $_POST['absd_um_nonce'] ) ), self::NONCE_ACTION ) ) {
			wp_die( esc_html__( 'Security check failed. Please try again.', 'absd-under-maintenance' ) );
		}

		$action = sanitize_key( wp_unslash( $_POST['absd_um_action'] ) );

		switch ( $action ) {
			case 'save_settings':
				$this->handle_save();
				break;
			case 'regenerate_token':
				$this->handle_regenerate_token();
				break;
			case 'revoke_token':
				$this->handle_revoke_token();
				break;
		}
	}

	/**
	 * Sanitize a raw (already unslashed) settings input array against the
	 * known fields. Shared by the save handler and the live preview AJAX
	 * endpoint — neither persists anything by itself.
	 *
	 * @param array $input Raw, unslashed input (e.g. from $_POST).
	 * @return array Sanitized settings.
	 */
	public function sanitize_input( array $input ) {
		$sanitized = array(
			'maintenance_mode' => ! empty( $input['maintenance_mode'] ),
			'template'         => $this->templates->exists( sanitize_key( $input['template'] ?? '' ) )
				? sanitize_key( $input['template'] )
				: $this->templates->get_default_id(),
			'logo_id'          => isset( $input['logo_id'] ) ? absint( $input['logo_id'] ) : 0,
			'background_id'    => isset( $input['background_id'] ) ? absint( $input['background_id'] ) : 0,
			'overlay_opacity'  => isset( $input['overlay_opacity'] ) ? min( 100, max( 0, absint( $input['overlay_opacity'] ) ) ) : 70,
			'heading'          => isset( $input['heading'] ) ? sanitize_text_field( $input['heading'] ) : '',
			'description'      => isset( $input['description'] ) ? sanitize_textarea_field( $input['description'] ) : '',
			'small_text'       => isset( $input['small_text'] ) ? sanitize_text_field( $input['small_text'] ) : '',
			'footer_text'      => isset( $input['footer_text'] ) ? wp_kses_post( $input['footer_text'] ) : '',
			'show_icon'        => ! empty( $input['show_icon'] ),
			'icon'             => $this->templates->icon_exists( sanitize_key( $input['icon'] ?? '' ) )
				? sanitize_key( $input['icon'] )
				: $this->templates->get_default_icon_id(),
			'icon_custom_id'   => isset( $input['icon_custom_id'] ) ? absint( $input['icon_custom_id'] ) : 0,
			'retry_text'       => isset( $input['retry_text'] ) ? sanitize_text_field( $input['retry_text'] ) : '',
			'show_contact'     => ! empty( $input['show_contact'] ),
			'contact_text'     => isset( $input['contact_text'] ) ? sanitize_text_field( $input['contact_text'] ) : '',
			'accent_color'     => isset( $input['accent_color'] ) ? sanitize_hex_color( $input['accent_color'] ) : '#c9a15a',
			'private_access'   => ! empty( $input['private_access'] ),
		);

		if ( empty( $sanitized['accent_color'] ) ) {
			$sanitized['accent_color'] = '#c9a15a';
		}

		return $sanitized;
	}

	/**
	 * Persist the settings form.
	 */
	private function handle_save() {
		// Nonce already verified in maybe_handle_actions() before this method is called.
		$input = wp_unslash( $_POST ); // phpcs:ignore WordPress.Security.NonceVerification.Missing

		$sanitized = $this->sanitize_input( $input );

		$this->update( $sanitized );

		// If private access was just enabled and there is no token yet, create one.
		if ( $sanitized['private_access'] && empty( $this->get( 'private_token' ) ) ) {
			$this->update( array( 'private_token' => absd_um_generate_token() ) );
		}

		wp_safe_redirect( add_query_arg( array( 'page' => 'absd-under-maintenance', 'absd_saved' => '1' ), admin_url( 'admin.php' ) ) );
		exit;
	}

	/**
	 * AJAX: render the maintenance page with the current (unsaved) form
	 * values so the admin can see a live preview. Nothing is persisted.
	 */
	public function ajax_preview() {
		if ( ! current_user_can( self::CAPABILITY ) ) {
			wp_send_json_error( array( 'message' => __( 'You do not have permission to perform this action.', 'absd-under-maintenance' ) ), 403 );
		}

		if ( ! isset( $_POST['absd_um_nonce'] ) || ! wp_verify_nonce( sanitize_text_field( wp_unslash( $_POST['absd_um_nonce'] ) ), self::NONCE_ACTION ) ) {
			wp_send_json_error( array( 'message' => __( 'Security check failed. Please reload the page.', 'absd-under-maintenance' ) ), 403 );
		}

		$input     = wp_unslash( $_POST ); // phpcs:ignore WordPress.Security.NonceVerification.Missing -- Verified above.
		$sanitized = $this->sanitize_input( $input );

		$maintenance = ABSD_Under_Maintenance::instance()->maintenance;
		$html        = $maintenance->render_template_preview( $sanitized, $sanitized['template'] );

		wp_send_json_success( array( 'html' => $html ) );
	}

	/**
	 * Regenerate the private access token.
	 */
	private function handle_regenerate_token() {
		$this->update( array( 'private_token' => absd_um_generate_token() ) );

		wp_safe_redirect( add_query_arg( array( 'page' => 'absd-under-maintenance', 'absd_token' => 'regenerated' ), admin_url( 'admin.php' ) ) );
		exit;
	}

	/**
	 * Revoke (clear) the private access token and disable private access.
	 */
	private function handle_revoke_token() {
		$this->update(
			array(
				'private_token'  => '',
				'private_access' => false,
			)
		);

		wp_safe_redirect( add_query_arg( array( 'page' => 'absd-under-maintenance', 'absd_token' => 'revoked' ), admin_url( 'admin.php' ) ) );
		exit;
	}

	/**
	 * Render the settings page (delegates to the view file).
	 */
	public function render_settings_page() {
		if ( ! current_user_can( self::CAPABILITY ) ) {
			wp_die( esc_html__( 'You do not have permission to access this page.', 'absd-under-maintenance' ) );
		}

		$settings  = $this->get_settings();
		$templates = $this->templates->get_templates();
		$icons     = $this->templates->get_icons();

		include ABSD_UM_PATH . 'admin/views/settings-page.php';
	}
}