<?php
// Prevent loading this file directly
defined( 'ABSPATH' ) || exit;
require_once RWMB_FIELDS_DIR . 'select-advanced.php';
require_once RWMB_FIELDS_DIR . 'checkbox-list.php';

if ( ! class_exists( 'RWMB_Taxonomy_Field' ) ) {
	class RWMB_Taxonomy_Field extends RWMB_Field {
		/**
		 * Enqueue scripts and styles
		 *
		 * @return void
		 */
		static function admin_enqueue_scripts() {
			RWMB_Select_Advanced_Field::admin_enqueue_scripts();
			wp_enqueue_style( 'rwmb-taxonomy', RWMB_CSS_URL . 'taxonomy.css', array(), RWMB_VER );
			wp_enqueue_script( 'rwmb-taxonomy', RWMB_JS_URL . 'taxonomy.js', array( 'rwmb-select-advanced' ), RWMB_VER, true );
		}

		/**
		 * Add default value for 'taxonomy' field
		 *
		 * @param $field
		 *
		 * @return array
		 */
		static function normalize_field( $field ) {
			$default_args = array(
				'hide_empty' => false,
			);

			// Set default args
			$field['options']['args'] = ! isset( $field['options']['args'] ) ? $default_args : wp_parse_args( $field['options']['args'], $default_args );

			$tax                  = get_taxonomy( $field['options']['taxonomy'] );
			$field['placeholder'] = empty( $field['placeholder'] ) ? sprintf( __( 'Select a %s', 'meta-box' ), $tax->labels->singular_name ) : $field['placeholder'];

			switch ( $field['options']['type'] ) {
				case 'select_advanced':
					$field = RWMB_Select_Advanced_Field::normalize_field( $field );
					break;
				case 'checkbox_list':
				case 'checkbox_tree':
					$field = RWMB_Checkbox_List_Field::normalize_field( $field );
					break;
				case 'select':
				case 'select_tree':
					$field = RWMB_Select_Field::normalize_field( $field );
					break;
				default:
					$field['options']['type'] = 'select';
					$field                    = RWMB_Select_Field::normalize_field( $field );
			}

			if ( in_array( $field['options']['type'], array( 'checkbox_tree', 'select_tree' ) ) ) {
				if ( isset( $field['options']['args']['parent'] ) ) {
					$field['options']['parent'] = $field['options']['args']['parent'];
					unset( $field['options']['args']['parent'] );
				} else {
					$field['options']['parent'] = 0;
				}
			}

			$field['field_name'] = "{$field['id']}[]";

			return $field;
		}

		/**
		 * Get field HTML
		 *
		 * @param $field
		 * @param $meta
		 *
		 * @return string
		 */
		static function html( $meta, $field ) {
			$options = $field['options'];
			$terms   = get_terms( $options['taxonomy'], $options['args'] );

			$field['options']      = self::get_options( $terms );
			$field['display_type'] = $options['type'];

			$html = '';

			switch ( $options['type'] ) {
				case 'checkbox_list':
					$html = RWMB_Checkbox_List_Field::html( $meta, $field );
					break;
				case 'checkbox_tree':
					$elements = self::process_terms( $terms );
					$html .= self::walk_checkbox_tree( $meta, $field, $elements, $options['parent'], true );
					break;
				case 'select_tree':
					$elements = self::process_terms( $terms );
					$html .= self::walk_select_tree( $meta, $field, $elements, $options['parent'], true );
					break;
				case 'select_advanced':
					$html = RWMB_Select_Advanced_Field::html( $meta, $field );
					break;
				case 'select':
				default:
					$html = RWMB_Select_Field::html( $meta, $field );
			}

			return $html;
		}

		/**
		 * Walker for displaying checkboxes in tree format
		 *
		 * @param      $meta
		 * @param      $field
		 * @param      $elements
		 * @param int  $parent
		 * @param bool $active
		 *
		 * @return string
		 */
		static function walk_checkbox_tree( $meta, $field, $elements, $parent = 0, $active = false ) {
			if ( ! isset( $elements[$parent] ) ) {
				return '';
			}
			$terms            = $elements[$parent];
			$field['options'] = self::get_options( $terms );
			$hidden           = $active ? '' : 'hidden';

			$html = "<ul class = 'rw-taxonomy-tree {$hidden}'>";
			$li   = '<li><label><input type="checkbox" name="%s" value="%s"%s> %s</label>';
			foreach ( $terms as $term ) {
				$html .= sprintf(
					$li,
					$field['field_name'],
					$term->term_id,
					checked( in_array( $term->term_id, $meta ), true, false ),
					$term->name
				);
				$html .= self::walk_checkbox_tree( $meta, $field, $elements, $term->term_id, $active && in_array( $term->term_id, $meta ) ) . '</li>';
			}
			$html .= '</ul>';

			return $html;
		}

		/**
		 * Walker for displaying select in tree format
		 *
		 * @param        $meta
		 * @param        $field
		 * @param        $elements
		 * @param int    $parent
		 * @param bool   $active
		 *
		 * @return string
		 */
		static function walk_select_tree( $meta, $field, $elements, $parent = 0, $active = false ) {
			if ( ! isset( $elements[$parent] ) ) {
				return '';
			}
			$terms            = $elements[$parent];
			$field['options'] = self::get_options( $terms );

			$classes   = array( 'rw-taxonomy-tree' );
			$classes[] = $active ? 'active' : 'disabled';
			$classes[] = "rwmb-taxonomy-{$parent}";

			$html = '<div class="' . implode( ' ', $classes ) . '">';
			$html .= RWMB_Select_Field::html( $meta, $field );
			foreach ( $terms as $term ) {
				$html .= self::walk_select_tree( $meta, $field, $elements, $term->term_id, $active && in_array( $term->term_id, $meta ) );
			}
			$html .= '</div>';

			return $html;
		}

		/**
		 * Processes terms into indexed array for walker functions
		 *
		 * @param $terms
		 *
		 * @internal param $field
		 * @return array
		 */
		static function process_terms( $terms ) {
			$elements = array();
			foreach ( $terms as $term ) {
				$elements[$term->parent][] = $term;
			}

			return $elements;
		}

		/**
		 * Get options for selects, checkbox list, etc via the terms
		 *
		 * @param array $terms Array of term objects
		 *
		 * @return array
		 */
		static function get_options( $terms = array() ) {
			$options = array();
			foreach ( $terms as $term ) {
				$options[$term->term_id] = $term->name;
			}

			return $options;
		}

		/**
		 * Save meta value
		 *
		 * @param mixed $new
		 * @param mixed $old
		 * @param int   $post_id
		 * @param array $field
		 *
		 * @return string
		 */
		static function save( $new, $old, $post_id, $field ) {
			$new = array_unique( array_map( 'intval', (array) $new ) );
			$new = empty( $new ) ? null : $new;
			wp_set_object_terms( $post_id, $new, $field['options']['taxonomy'] );
		}

		/**
		 * Standard meta retrieval
		 *
		 * @param int   $post_id
		 * @param bool  $saved
		 * @param array $field
		 *
		 * @return array
		 */
		static function meta( $post_id, $saved, $field ) {
			$options = $field['options'];

			$meta = wp_get_post_terms( $post_id, $options['taxonomy'] );
			$meta = is_array( $meta ) ? $meta : (array) $meta;
			$meta = wp_list_pluck( $meta, 'term_id' );

			return $meta;
		}

		/**
		 * Get the field value
		 * Return list of post term objects
		 *
		 * @param  array    $field   Field parameters
		 * @param  array    $args    Additional arguments. Rarely used. See specific fields for details
		 * @param  int|null $post_id Post ID. null for current post. Optional.
		 *
		 * @return array List of post term objects
		 */
		static function get_value( $field, $args = array(), $post_id = null ) {
			if ( ! $post_id ) {
				$post_id = get_the_ID();
			}

			$value = wp_get_post_terms( $post_id, $field['options']['taxonomy'] );

			// Get single value if necessary
			if ( ! $field['clone'] && ! $field['multiple'] ) {
				$value = reset( $value );
			}

			return $value;
		}

		/**
		 * Output the field value
		 * Display unordered list of option labels, not option values
		 *
		 * @param  array    $field   Field parameters
		 * @param  array    $args    Additional arguments. Not used for these fields.
		 * @param  int|null $post_id Post ID. null for current post. Optional.
		 *
		 * @return string Link(s) to post
		 */
		static function the_value( $field, $args = array(), $post_id = null ) {
			$class = RW_Meta_Box::get_class_name( $field );
			$value = call_user_func( array( $class, 'get_value' ), $field, $args, $post_id );
			if ( ! $value || is_wp_error( $value ) ) {
				return '';
			}

			$function = array( $class, 'get_option_label' );

			if ( $field['clone'] ) {
				$output = '<ul>';
				if ( $field['multiple'] ) {
					foreach ( $value as $subvalue ) {
						$output .= '<li>';
						array_walk_recursive( $subvalue, $function, $field );
						$output .= '<ul><li>' . implode( '</li><li>', $subvalue ) . '</li></ul>';
						$output .= '</li>';
					}
				} else {
					array_walk_recursive( $value, $function, $field );
					$output = '<li>' . implode( '</li><li>', $value ) . '</li>';
				}
				$output .= '</ul>';
			} else {
				if ( $field['multiple'] ) {
					array_walk_recursive( $value, $function, $field );
					$output = '<ul><li>' . implode( '</li><li>', $value ) . '</li></ul>';
				} else {
					call_user_func_array( $function, array( &$value, 0, $field ) );
					$output = $value;
				}
			}

			return $output;
		}

		/**
		 * Get post link to display in the frontend
		 *
		 * @param object $value Option value, e.g. term object
		 * @param int    $index Array index
		 * @param array  $field Field parameter
		 *
		 * @return string
		 */
		static function get_option_label( &$value, $index, $field ) {
			$value = sprintf(
				'<a href="%s" title="%s">%s</a>',
				esc_url( get_term_link( $value ) ),
				esc_attr( $value->name ),
				$value->name
			);
		}
	}
}