class-settings-form.php

<?php
/**
 * Class Settings_Form
 *
 * @package wpct-plugin
 */

// phpcs:disable WordPress.NamingConventions.PrefixAllGlobals
// phpcs:disable WordPress.WP.I18n.TextDomainMismatch

namespace WPCT_PLUGIN;

use ArgumentCountError;

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

/**
 * Settings form base class. Handles the admin page UI of the settings store.
 */
class Settings_Form extends Singleton {

	/**
	 * Escape admin fields html.
	 *
	 * @param string $html Output rendered field.
	 *
	 * @return string Escaped html.
	 */
	public static function kses( $html ) {
		return wp_kses(
			$html,
			array(
				'table'  => array(
					'id'    => array(),
					'class' => array(),
				),
				'th'     => array(),
				'tr'     => array(),
				'td'     => array(),
				'input'  => array(
					'type'    => array(),
					'value'   => array(),
					'name'    => array(),
					'id'      => array(),
					'checked' => array(),
				),
				'select' => array(
					'name'     => array(),
					'id'       => array(),
					'multiple' => array(),
					'required' => array(),
				),
				'option' => array(
					'value'    => array(),
					'selected' => array(),
				),
				'div'    => array(
					'id'    => array(),
					'class' => array(),
				),
				'button' => array(
					'class'       => array(),
					'data-action' => array(),
				),
			)
		);
	}

	/**
	 * Class constructor. Gets the store instance and bind it to wp admin hooks.
	 *
	 * @param array{0: Settings_Store} ...$args Constructor arguments with a store instance in the first position.
	 *
	 * @throws ArgumentCountError If store is not passed as an input argument.
	 */
	protected function construct( ...$args ) {
		if ( empty( $args ) ) {
			throw new ArgumentCountError( 'Too few arguments to Settigs Form constructor' );
		}

		/**
		 * Store instance.
		 *
		 * @var Settings_Store
		 */
		$store = $args[0];

		add_action(
			'admin_init',
			static function () use ( $store ) {
				foreach ( $store::settings() as $setting ) {
					$setting_name  = $setting->option();
					$section_name  = $setting_name . '_section';
					$section_title = esc_html(
						static::setting_title( $setting_name )
					);

					add_settings_section(
						$section_name,
						$section_title,
						static function () use ( $setting_name ) {
							$description = static::setting_description(
								$setting_name
							);
							printf( '<p>%s</p>', esc_html( $description ) );
						},
						$setting_name
					);

					$fields = array_keys( $setting->schema()['properties'] );
					foreach ( $fields as $field ) {
						static::add_setting_field( $setting, $field );
					}
				}
			}
		);

		add_action(
			'admin_enqueue_scripts',
			static function () {
				$plugin_url = plugin_dir_url( __FILE__ );

				wp_enqueue_script(
					'wpct-plugin-fieldset-control',
					$plugin_url . 'admin-form.js',
					array(),
					'1.0.0',
					array( 'in_footer' => true )
				);

				wp_enqueue_style(
					'wpct-plugin-admin-style',
					$plugin_url . 'admin-form.css',
					array(),
					'1.0.0'
				);
			},
			10,
			0
		);
	}

	/**
	 * Registers a setting field.
	 *
	 * @param Setting $setting Setting name.
	 * @param string  $field Field name.
	 */
	private static function add_setting_field( $setting, $field ) {
		$setting_name = $setting->option();
		$field_label  = esc_html( static::field_label( $field, $setting_name ) );

		add_settings_field(
			$field,
			$field_label,
			static function () use ( $setting, $field ) {
				$setting_name = $setting->option();
				$schema       = $setting->schema( $field );
				$value        = $setting->data( $field );

				// phpcs:disable WordPress.Security.EscapeOutput
				echo static::kses(
					static::field_render(
						$setting_name,
						$field,
						$schema,
						$value
					)
				);
				// phpcs:enable WordPress.Security.EscapeOutput
			},
			$setting_name,
			$setting_name . '_section'
		);
	}

	/**
	 * Renders the field HTML.
	 *
	 * @param string $setting Setting name.
	 * @param string $field Field name.
	 * @param array  $schema Field schema.
	 * @param mixed  $value Field value.
	 *
	 * @return string
	 */
	private static function field_render( $setting, $field, $schema, $value ) {
		if ( ! in_array( $schema['type'], array( 'array', 'object' ), true ) ) {
			return static::input_render( $setting, $field, $schema, $value );
		} elseif ( 'array' === $schema['type'] && isset( $schema['enum'] ) ) {
			return self::input_render( $setting, $field, $schema, $value );
		} else {
			$fieldset = static::fieldset_render(
				$setting,
				$field,
				$schema,
				$value
			);
			if ( 'array' === $schema['type'] ) {
				$fieldset .= static::control_render( $setting, $field );
			}
			return $fieldset;
		}
	}

	/**
	 * Render input HTML.
	 *
	 * @param string $setting Setting name.
	 * @param string $field Field name.
	 * @param array  $schema Field schema.
	 * @param mixed  $value Field value.
	 *
	 * @return string
	 */
	protected static function input_render(
		$setting,
		$field,
		$schema,
		$value
	) {
		if ( 'boolean' === $schema['type'] ) {
			return sprintf(
				'<input type="checkbox" name="%s" ' .
					( $value ? 'checked="true"' : '' ) .
					' />',
				esc_attr( $setting . "[{$field}]" )
			);
		} elseif ( 'string' === $schema['type'] && isset( $schema['enum'] ) && is_array( $schema['enum'] ) ) {
			$options = '';

			$enum_opts = (array) $schema['enum'];
			foreach ( $enum_opts as $opt ) {
				$is_selected = $opt === $value;
				$options    .= sprintf(
					'<option value="%s" %s>%s</option>',
					esc_attr( $opt ),
					$is_selected ? 'selected' : '',
					esc_html( $opt )
				);
			}

			return sprintf(
				'<select name="%s">%s</select>',
				esc_attr( $setting . "[{$field}]" ),
				$options
			);
		} elseif ( 'array' === $schema['type'] && isset( $schema['enum'] ) ) {
			$value   = (array) $value;
			$options = '';

			$enum_opts = (array) $schema['enum'];
			foreach ( $enum_opts as $opt ) {
				$is_selected = in_array( $opt, $value, true );
				$options    .= sprintf(
					'<option value="%s" %s>%s</option>',
					esc_attr( $opt ),
					$is_selected ? 'selected' : '',
					esc_html( $opt )
				);
			}

			return sprintf(
				'<select name="%s[]" multiple required>%s</select>',
				esc_attr( $setting . "[{$field}]" ),
				$options
			);
		} else {
			return sprintf(
				'<input type="text" name="%s" value="%s" />',
				esc_attr( $setting . "[{$field}]" ),
				esc_attr( $value )
			);
		}
	}

	/**
	 * Render fieldset HTML.
	 *
	 * @param Setting $setting Setting instance.
	 * @param string  $field Field name.
	 * @param array   $schema Field schema.
	 * @param mixed   $value Field value.
	 *
	 * @return string $html Fieldset HTML.
	 */
	private static function fieldset_render(
		$setting,
		$field,
		$schema,
		$value
	) {
		$is_list = 'array' === $schema['type'];

		$table_id = $setting . '__' . str_replace( '][', '_', $field );
		$fieldset = '<table id="' . esc_attr( $table_id ) . '"';

		if ( $is_list ) {
			$fieldset .= ' class="is-list"';
		}

		$fieldset .= '>';

		$value = (array) $value;
		foreach ( array_keys( $value ) as $key ) {
			$fieldset .= '<tr>';

			if ( ! $is_list ) {
				$fieldset .= '<th>' . esc_html( $key ) . '</th>';
			} else {
				$key = (int) $key;
			}

			if ( 'object' === $schema['type'] ) {
				$sub_schema = $schema['properties'][ $key ];
			} else {
				$sub_schema = $schema['items'];
			}

			$sub_value = $value[ $key ];
			$sub_field = $field . '][' . $key;

			$fieldset .= sprintf(
				'<td>%s</td></td>',
				self::field_render(
					$setting,
					$sub_field,
					$sub_schema,
					$sub_value
				)
			);
		}

		return $fieldset . '</table>';
	}

	/**
	 * Render control HTML.
	 *
	 * @param Setting $setting Setting instance.
	 * @param string  $field Field name.
	 *
	 * @return string $html Control HTML.
	 */
	private static function control_render( $setting, $field ) {
		$field_id = str_replace( '][', '_', $field );
		ob_start();
		?>
			<div id="
		<?php
		echo esc_attr(
			$setting . '__' . $field_id . '--controls'
		);
		?>
			" class="wpct-plugin-fieldset-control">
				<button class="button button-primary" data-action="add">
			<?php
			echo esc_html(
				__( 'Add', 'wpct-plugin' )
			);
			?>
				</button>
				<button class="button button-secondary" data-action="remove">
				<?php
				echo esc_html(
					__( 'Remove', 'wpct-plugin' )
				);
				?>
				</button>
			</div>
			<?php
			return ob_get_clean();
	}

	/**
	 * To be overwriten by the child class. Should return the localized setting title
	 * for the menu page.
	 *
	 * @param string $setting_name Setting name.
	 *
	 * @return string
	 */
	protected static function setting_title( $setting_name ) {
		return $setting_name;
	}

	/**
	 * To be overwriten by the child class. Should return the localized setting description
	 * for the menu page.
	 *
	 * @param string $setting_name Setting name.
	 *
	 * @return string
	 */
	protected static function setting_description( $setting_name ) {
		return 'Setting description';
	}

	/**
	 * To be overwriten by the child class. Should return the localized
	 * field label for the menu page.
	 *
	 * @param string $field_name Name of the field.
	 * @param string $setting_name Name of the parent setting.
	 *
	 * @return string
	 */
	protected static function field_label( $field_name, $setting_name ) {
		return $field_name;
	}
}