<?php
/**
 * Loads administrative capabilities for configuring Also In This Series.
 *
 */

class AlsoInThisSeriesAdmin {
	const settings_page = 'AlsoInThisSeries-plugin-settings';
	private static $registeredfields = array();

	// To be hooked into admin_init
	static function admin_init() {
		register_setting( AlsoInThisSeries::slug, AlsoInThisSeries::slug, array( __CLASS__, 'validateFields' ) );
		self::addSection( 'general-settings-section', __( 'General Settings', 'also-in-this-series' ) );

		// Add theme options here
		self::addField( 'radiobutton', 'insert-in-content', __( 'Automatically insert series listing into posts included in a series?', 'also-in-this-series' ), array( '', 'append', 'prepend' ), array( 'No', 'After Content', 'Before Content' ) );
		self::addField( 'radiobutton', 'archive-sort-order', __( 'Order of series on archive page:', 'also-in-this-series' ), array( '', 'asc', 'desc' ), array( 'Default', 'Oldest First', 'Newest First' ) );
		self::addField( 'textfield', 'window-series-listing', __( 'Restrict series listing in posts?', 'also-in-this-series' ), '^[[:digit:]]*$', 'number of surrounding posts' );
	}

	static function add_meta_boxes() {
	}

	static function save_post( $postid ) {
	}

	static function manage_posts_columns( $columns ) {
		$columns[ 'posts_series' ] = 'Series';
		return $columns;
	}

	static function manage_posts_custom_column( $column ) {
		if( 'posts_series' == $column )
			echo get_the_term_list( get_the_ID(), AlsoInThisSeries::taxonomy, '', ', ', ' ' );
	}

	// To be hooked into wp_enqueue_scripts or another appropriate hook suitable for enqueuing scripts.
	static function admin_print_scripts( $context ) {
		wp_enqueue_script( 'also-in-this-series-admin-scripts', plugins_url( '/resources/js/admin-scripts.js', __FILE__ ) );
	}

	// To be hooked into admin_menu.
	static function admin_menu() {
		$pagehook = add_options_page(
			__('Also In This Series settings', 'also-in-this-series'),
			__('Also In This Series', 'also-in-this-series'),
			'manage_options',
			self::settings_page,
			array( __CLASS__, 'showPluginSettings' )
		);

		// Only load admin scripts when on Also In This Series admin page.
		add_action( 'admin_print_scripts-' . $pagehook, array( __CLASS__, 'admin_print_scripts' ) );
	}

	// Use this for adding sections to the admin page.
	static function addSection( $id, $title ) {
		add_settings_section($id, $title, array( __CLASS__, 'sectionHeader'), self::settings_page );
	}

	// Use this for adding theme options to the admin page. See code below for available types (renderers).
	static function addField( $type, $id, $title, $value = 1, $label = null, $args = array(), $section = 'general-settings-section' ) {
		self::_addFieldFilter( $type, $id, $title, $value, $args );
		add_settings_field( $id, $title, array(__CLASS__, $type . 'Renderer'), self::settings_page, $section, compact( 'type', 'id', 'value', 'label', 'args', 'section' ) );
	}

	// Callback for loading the admin view.
	static function showPluginSettings() {
		include( 'views/admin/settings.php' );
	}

	// Callback for displaying a section header.
	static function sectionHeader( $args ) {

	}

	// Renders a textfield.
	static function textfieldRenderer( $args ) {
		$setting = AlsoInThisSeries::config( $args[ 'id' ] );

		$id = AlsoInThisSeries::slug . '_' . $args[ 'id' ];
		$name = AlsoInThisSeries::slug . "[{$args[ 'id' ]}]";
		$value = $setting;
		$label = $args[ 'label' ];

		self::_fieldRenderer( 'textfield', compact( 'id', 'name', 'value', 'label' ) );
	}

	// Renders a checkbox. If multiple values are provided, an option group will be rendered.
	static function checkboxRenderer( $args ) {
		$multivalue = is_array( $args[ 'value' ] );
		$settings = (array) AlsoInThisSeries::config( $args[ 'id' ] );

		$id = AlsoInThisSeries::slug . '_' . $args[ 'id' ];
		$name = AlsoInThisSeries::slug . "[{$args[ 'id' ]}]" . ( $multivalue ? '[]' : '' );
		$values = (array) $args[ 'value' ];
		array_walk( $values, 'esc_attr' );
		$checked = array();
		$labels = (array) $args[ 'label' ];

		foreach( $settings as $index => $setting )
			$checked[$index] = checked( 1, $setting ? 1 : 0, false );

		self::_fieldRenderer( 'checkbox', compact( 'id', 'name', 'values', 'checked', 'labels' ) );
	}

	// Renders a radiobox. More than one value should be provided as an option group.
	static function radiobuttonRenderer( $args ) {
		$setting = AlsoInThisSeries::config( $args[ 'id' ] );

		$id = AlsoInThisSeries::slug . '_' . $args[ 'id' ];
		$name = AlsoInThisSeries::slug . "[{$args[ 'id' ]}]";
		$values = (array) $args[ 'value' ];
		array_walk( $values, 'esc_attr' );
		$checked = array();
		$labels = (array) $args[ 'label' ];

		foreach( $values as $index => $value )
			$checked[$index] = checked( $value, $setting, false );

		self::_fieldRenderer( 'radiobutton', compact( 'id', 'name', 'values', 'checked', 'labels' ) );
	}

	// Validates raw input from option submission.
	static function validateFields( $fields ) {
		$validated = array();

		foreach( $fields as $field => $value ) {
			if( ! $sanction = isset( self::$registeredfields[ $field ] ) ? self::$registeredfields[ $field ] : false )
				continue;

			$valid = true;
			if( ! empty( $sanction[ 'args' ][ 'raw' ] ) )
				;//allow raw
			elseif( is_scalar( $value ) )
				$value = sanitize_text_field( $value );
			elseif( is_array( $value ) )
				$value = array_map( 'sanitize_text_field', $value );

			switch( $sanction[ 'type' ] ) {
				case 'textfield' :

				if( $sanction[ 'value' ] && ! preg_match( "/{$sanction[ 'value' ]}/", $value ) ) {
					add_settings_error( AlsoInThisSeries::slug, 'invalid-value', "'{$sanction[ 'title' ]}' <strong>Invalid input</strong>" );
					$valid = false;
					break;
				}
				break;

				case 'checkbox' :
				case 'radiobox' :

				if( is_scalar( $sanction[ 'value' ] ) && $value != $sanction[ 'value' ] ) {
					$valid = false;
					add_settings_error( AlsoInThisSeries::slug, 'invalid-value', "'{$sanction[ 'title' ]}' <strong>Invalid input</strong>" );
				}
				elseif( is_array( $sanction[ 'value' ] ) && array_diff( (array) $value, $sanction[ 'value' ] ) ) {
					$valid = false;
					add_settings_error( AlsoInThisSeries::slug, 'invalid-value', "'{$sanction[ 'title' ]}' <strong>Invalid input</strong>" );
				}

				default :
			}

			if( $valid ) $validated[ $field ] = $value;
		}

		return apply_filters( 'alsointhisseries_validate_fields', $validated, $fields );
	}

	// Adds theme option to sanctioned list. Should be called when a field is added.
	private static function _addFieldFilter( $type, $id, $title, $value, $args ) {
		self::$registeredfields[ $id ] = compact( 'type', 'title', 'value', 'args' );
	}

	// Delegates UI rendering to the template fragment loader.
	private static function _fieldRenderer( $type, $params ) {
		extract( $params );
		include( "views/admin/optionsfield-{$type}.php" );
	}
}

// Register admin functionality.
add_action( 'admin_menu', array( 'AlsoInThisSeriesAdmin', 'admin_menu' ) );
add_action( 'admin_init', array( 'AlsoInThisSeriesAdmin', 'admin_init' ) );
add_action( 'add_meta_boxes', array( 'AlsoInThisSeriesAdmin', 'add_meta_boxes' ) );
add_action( 'save_post', array( 'AlsoInThisSeriesAdmin', 'save_post' ) );

add_filter( 'manage_posts_columns', array( 'AlsoInThisSeriesAdmin', 'manage_posts_columns' ) );
add_filter( 'manage_posts_custom_column', array( 'AlsoInThisSeriesAdmin', 'manage_posts_custom_column' ) );