<?php
/**
 * Main plugin class.
 *
 * @package AetosRTLInputDirectionFixer
 */

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

/**
 * Apply narrowly-scoped LTR styles to technical input fields on RTL sites.
 */
final class Aetos_RTL_Input_Direction_Fixer {

	const OPTION_NAME        = 'aetos_rtl_input_direction_settings';
	const SETTINGS_GROUP     = 'aetos_rtl_input_direction_settings_group';
	const SETTINGS_PAGE_SLUG = 'aetos-rtl-input-direction-fixer';

	/**
	 * Register plugin hooks after WordPress initialization.
	 *
	 * @return void
	 */
	public static function init() {
		$plugin = new self();
		$plugin->register_hooks();
	}

	/**
	 * Register runtime and admin hooks.
	 *
	 * @return void
	 */
	private function register_hooks() {
		add_action( 'wp_enqueue_scripts', array( $this, 'enqueue_frontend_styles' ), 20 );
		add_action( 'admin_enqueue_scripts', array( $this, 'enqueue_admin_styles' ), 20 );
		add_action( 'login_enqueue_scripts', array( $this, 'enqueue_login_styles' ), 20 );
		add_action( 'admin_init', array( $this, 'register_settings' ) );
		add_action( 'admin_menu', array( $this, 'register_settings_page' ) );
		add_filter(
			'plugin_action_links_' . plugin_basename( AETOS_RTL_INPUT_DIRECTION_FILE ),
			array( $this, 'add_settings_link' )
		);
	}

	/**
	 * Enqueue the technical-field styles on the front end when enabled.
	 *
	 * @return void
	 */
	public function enqueue_frontend_styles() {
		$settings = $this->get_settings();

		if ( ! is_rtl() || ! $settings['frontend'] ) {
			return;
		}

		$this->enqueue_direction_styles( $settings );
	}

	/**
	 * Enqueue the technical-field styles in wp-admin when enabled.
	 *
	 * The plugin settings screen always loads the base stylesheet on RTL sites so
	 * its field preview remains useful even when global admin styling is disabled.
	 *
	 * @param string $hook_suffix Current admin page hook suffix.
	 * @return void
	 */
	public function enqueue_admin_styles( $hook_suffix ) {
		if ( ! is_rtl() ) {
			return;
		}

		$settings         = $this->get_settings();
		$is_settings_page = 'settings_page_' . self::SETTINGS_PAGE_SLUG === $hook_suffix;

		if ( ! $settings['admin'] && ! $is_settings_page ) {
			return;
		}

		$this->enqueue_direction_styles( $settings );
	}

	/**
	 * Enqueue the technical-field styles on the WordPress login screen.
	 *
	 * @return void
	 */
	public function enqueue_login_styles() {
		$settings = $this->get_settings();

		if ( ! is_rtl() || ! $settings['login'] ) {
			return;
		}

		$this->enqueue_direction_styles( $settings );
	}

	/**
	 * Enqueue static styles without constructing dynamic CSS.
	 *
	 * @param array<string,bool> $settings Current settings.
	 * @return void
	 */
	private function enqueue_direction_styles( $settings ) {
		wp_enqueue_style(
			'aetos-rtl-input-direction-technical-fields',
			plugins_url( 'assets/css/technical-fields.css', AETOS_RTL_INPUT_DIRECTION_FILE ),
			array(),
			AETOS_RTL_INPUT_DIRECTION_VERSION
		);

		if ( $settings['username_fields'] ) {
			wp_enqueue_style(
				'aetos-rtl-input-direction-username-fields',
				plugins_url( 'assets/css/username-fields.css', AETOS_RTL_INPUT_DIRECTION_FILE ),
				array( 'aetos-rtl-input-direction-technical-fields' ),
				AETOS_RTL_INPUT_DIRECTION_VERSION
			);
		}
	}

	/**
	 * Register the settings array and its sanitization callback.
	 *
	 * @return void
	 */
	public function register_settings() {
		register_setting(
			self::SETTINGS_GROUP,
			self::OPTION_NAME,
			array(
				'type'              => 'array',
				'sanitize_callback' => array( $this, 'sanitize_settings' ),
				'default'           => $this->get_default_settings(),
				'show_in_rest'      => false,
			)
		);
	}

	/**
	 * Sanitize checkbox settings into a fixed boolean shape.
	 *
	 * @param mixed $input Raw settings value.
	 * @return array<string,bool>
	 */
	public function sanitize_settings( $input ) {
		if ( ! is_array( $input ) ) {
			$input = array();
		}

		return array(
			'frontend'        => ! empty( $input['frontend'] ),
			'admin'           => ! empty( $input['admin'] ),
			'login'           => ! empty( $input['login'] ),
			'username_fields' => ! empty( $input['username_fields'] ),
		);
	}

	/**
	 * Register the plugin settings page under Settings.
	 *
	 * @return void
	 */
	public function register_settings_page() {
		add_options_page(
			esc_html__( 'Aetos RTL Input Direction Fixer', 'aetos-rtl-input-direction-fixer' ),
			esc_html__( 'Aetos RTL Input Direction', 'aetos-rtl-input-direction-fixer' ),
			'manage_options',
			self::SETTINGS_PAGE_SLUG,
			array( $this, 'render_settings_page' )
		);
	}

	/**
	 * Add a Settings shortcut on the Plugins screen.
	 *
	 * @param array<int,string> $links Existing plugin action links.
	 * @return array<int,string>
	 */
	public function add_settings_link( $links ) {
		$settings_link = sprintf(
			'<a href="%1$s">%2$s</a>',
			esc_url( admin_url( 'options-general.php?page=' . self::SETTINGS_PAGE_SLUG ) ),
			esc_html__( 'Settings', 'aetos-rtl-input-direction-fixer' )
		);

		array_unshift( $links, $settings_link );
		return $links;
	}

	/**
	 * Render the settings page.
	 *
	 * @return void
	 */
	public function render_settings_page() {
		if ( ! current_user_can( 'manage_options' ) ) {
			return;
		}

		$settings = $this->get_settings();
		?>
		<div class="wrap">
			<h1><?php echo esc_html__( 'Aetos RTL Input Direction Fixer', 'aetos-rtl-input-direction-fixer' ); ?></h1>
			<p><?php echo esc_html__( 'Keep technical values readable from left to right while the surrounding WordPress interface remains right to left.', 'aetos-rtl-input-direction-fixer' ); ?></p>

			<?php settings_errors(); ?>

			<form method="post" action="<?php echo esc_url( admin_url( 'options.php' ) ); ?>">
				<?php settings_fields( self::SETTINGS_GROUP ); ?>
				<table class="form-table" role="presentation">
					<tbody>
						<?php
						foreach ( $this->get_checkbox_fields() as $setting_key => $setting_field ) {
							$this->render_checkbox_row(
								$settings,
								$setting_key,
								$setting_field['label'],
								$setting_field['description']
							);
						}
						$this->render_locale_status_row();
						$this->render_preview_row();
						?>
					</tbody>
				</table>
				<?php submit_button(); ?>
			</form>
		</div>
		<?php
	}

	/**
	 * Return checkbox labels and descriptions.
	 *
	 * @return array<string,array<string,string>>
	 */
	private function get_checkbox_fields() {
		return array(
			'frontend'        => array(
				'label'       => __( 'Front-end forms', 'aetos-rtl-input-direction-fixer' ),
				'description' => __( 'Apply the fix to public-facing email, URL, telephone, and password fields.', 'aetos-rtl-input-direction-fixer' ),
			),
			'admin'           => array(
				'label'       => __( 'WordPress admin', 'aetos-rtl-input-direction-fixer' ),
				'description' => __( 'Apply the same narrow fix to technical fields inside wp-admin.', 'aetos-rtl-input-direction-fixer' ),
			),
			'login'           => array(
				'label'       => __( 'Login screen', 'aetos-rtl-input-direction-fixer' ),
				'description' => __( 'Keep password and other technical login fields left to right on RTL login screens.', 'aetos-rtl-input-direction-fixer' ),
			),
			'username_fields' => array(
				'label'       => __( 'Username-like fields', 'aetos-rtl-input-direction-fixer' ),
				'description' => __( 'Also target fields identified as usernames. Leave this off when Arabic usernames are expected.', 'aetos-rtl-input-direction-fixer' ),
			),
		);
	}

	/**
	 * Render the active-locale status row.
	 *
	 * @return void
	 */
	private function render_locale_status_row() {
		?>
		<tr>
			<th scope="row"><?php echo esc_html__( 'Current locale status', 'aetos-rtl-input-direction-fixer' ); ?></th>
			<td>
				<?php if ( is_rtl() ) : ?>
					<strong><?php echo esc_html__( 'RTL detected. Enabled contexts receive the direction fix.', 'aetos-rtl-input-direction-fixer' ); ?></strong>
				<?php else : ?>
					<strong><?php echo esc_html__( 'LTR detected. No direction styles are loaded.', 'aetos-rtl-input-direction-fixer' ); ?></strong>
				<?php endif; ?>
				<p class="description"><?php echo esc_html__( 'The plugin follows the active WordPress locale and does not force the whole site into RTL mode.', 'aetos-rtl-input-direction-fixer' ); ?></p>
			</td>
		</tr>
		<?php
	}

	/**
	 * Render the technical-field preview row.
	 *
	 * @return void
	 */
	private function render_preview_row() {
		?>
		<tr>
			<th scope="row"><?php echo esc_html__( 'Field preview', 'aetos-rtl-input-direction-fixer' ); ?></th>
			<td><?php $this->render_field_preview(); ?></td>
		</tr>
		<?php
	}

	/**
	 * Render one accessible checkbox settings row.
	 *
	 * @param array<string,bool> $settings    Current settings.
	 * @param string             $key         Setting key.
	 * @param string             $label       Field label.
	 * @param string             $description Field description.
	 * @return void
	 */
	private function render_checkbox_row( $settings, $key, $label, $description ) {
		$field_id       = 'aetos-rtl-input-direction-' . $key;
		$description_id = $field_id . '-description';
		?>
		<tr>
			<th scope="row">
				<label for="<?php echo esc_attr( $field_id ); ?>"><?php echo esc_html( $label ); ?></label>
			</th>
			<td>
				<input
					type="checkbox"
					id="<?php echo esc_attr( $field_id ); ?>"
					name="<?php echo esc_attr( self::OPTION_NAME . '[' . $key . ']' ); ?>"
					value="1"
					aria-describedby="<?php echo esc_attr( $description_id ); ?>"
					<?php checked( ! empty( $settings[ $key ] ) ); ?>
				/>
				<p id="<?php echo esc_attr( $description_id ); ?>" class="description"><?php echo esc_html( $description ); ?></p>
			</td>
		</tr>
		<?php
	}

	/**
	 * Render static examples without collecting or saving any entered data.
	 *
	 * @return void
	 */
	private function render_field_preview() {
		foreach ( $this->get_preview_fields() as $input_type => $preview_field ) {
			$this->render_preview_input( $input_type, $preview_field );
		}

		if ( ! is_rtl() ) {
			?>
			<p class="description"><?php echo esc_html__( 'Use an RTL site or user locale to see the direction fix in this preview.', 'aetos-rtl-input-direction-fixer' ); ?></p>
			<?php
		}
	}

	/**
	 * Return static preview field definitions.
	 *
	 * @return array<string,array<string,string>>
	 */
	private function get_preview_fields() {
		return array(
			'email'    => array(
				'label' => __( 'Email', 'aetos-rtl-input-direction-fixer' ),
				'value' => 'hello@example.com',
			),
			'tel'      => array(
				'label' => __( 'Telephone', 'aetos-rtl-input-direction-fixer' ),
				'value' => '+966 50 123 4567',
			),
			'url'      => array(
				'label' => __( 'URL', 'aetos-rtl-input-direction-fixer' ),
				'value' => 'https://example.com/path',
			),
			'password' => array(
				'label' => __( 'Password', 'aetos-rtl-input-direction-fixer' ),
				'value' => 'Example-1234',
			),
		);
	}

	/**
	 * Render one static preview input.
	 *
	 * @param string               $input_type    HTML input type.
	 * @param array<string,string> $preview_field Preview label and value.
	 * @return void
	 */
	private function render_preview_input( $input_type, $preview_field ) {
		$field_id = 'aetos-rtl-input-direction-preview-' . $input_type;
		?>
		<p>
			<label for="<?php echo esc_attr( $field_id ); ?>"><strong><?php echo esc_html( $preview_field['label'] ); ?></strong></label><br />
			<input
				type="<?php echo esc_attr( $input_type ); ?>"
				id="<?php echo esc_attr( $field_id ); ?>"
				class="regular-text"
				value="<?php echo esc_attr( $preview_field['value'] ); ?>"
				readonly
			/>
		</p>
		<?php
	}

	/**
	 * Return settings merged with fixed defaults.
	 *
	 * @return array<string,bool>
	 */
	private function get_settings() {
		$settings = get_option( self::OPTION_NAME, array() );

		if ( ! is_array( $settings ) ) {
			$settings = array();
		}

		$settings = wp_parse_args( $settings, $this->get_default_settings() );

		return array(
			'frontend'        => (bool) $settings['frontend'],
			'admin'           => (bool) $settings['admin'],
			'login'           => (bool) $settings['login'],
			'username_fields' => (bool) $settings['username_fields'],
		);
	}

	/**
	 * Return conservative default settings.
	 *
	 * @return array<string,bool>
	 */
	private function get_default_settings() {
		return array(
			'frontend'        => true,
			'admin'           => true,
			'login'           => true,
			'username_fields' => false,
		);
	}
}