Term Meta Generator

                    class wpturbo_CustomTermMeta{

	private $fields = array(
	);
	
	public function __construct(){
		if ( is_admin() ) {
			// Register all the hooks.
			add_action( 'category_add_form_fields', array( $this, 'wpturbo_render_meta_fields' ), 10, 2 );
			add_action( 'category_edit_form_fields', array( $this, 'wpturbo_edit_meta_fields' ),  10, 2 );
			add_action( 'created_category', array( $this, 'wpturbo_save_meta_fields' ), 10, 1 );
			add_action( 'edited_category',  array( $this, 'wpturbo_save_meta_fields' ), 10, 1 );
		}
	}
	// Render fields on the add taxonomy page.
	public function wpturbo_render_meta_fields($taxonomy){
		$html = '';
		foreach( $this->fields as $field_id => $field ){
			$meta_value = '';
			if ( isset( $field['default'] ) ) {
				$meta_value = $field['default'];
			}
	
			$field_html = $this->wpturbo_render_input_field($field_id, $field, $meta_value);
			$label = "<label for='$field_id'>{$field['label']}</label>";
			$html .= $this->wpturbo_format_field($label, $field_html);
		}
		echo $html;
	}
	
	// Render fields on the edit taxonomy page.
	public function wpturbo_edit_meta_fields($term, $taxonomy) {
		$html = '';
		foreach( $this->fields as $field_id => $field ){
			$meta_value = get_term_meta( $term->term_id, $field_id, true );
			$field_html = $this->wpturbo_render_input_field($field_id, $field, $meta_value);
			$label = "<label for='$field_id'>{$field['label']}</label>";
			$html .= $this->wpturbo_format_field($label, $field_html);
		}
		echo $html;
	}
	
	// Format every field to table display.
	public function wpturbo_format_field($label, $field){
		return '<tr class="form-field"><th>'.$label.'</th><td>'.$field.'</td></tr>';
	}
	
	// Render each individual field.
	public function wpturbo_render_input_field($field_id, $field, $field_value){
		switch($field['type']){
			case 'select': {
				$field_html = '<select name="'.$field_id.'" id="'.$field_id.'">';
					foreach($field['options'] as $key => $value){
						$key = !is_numeric( $key ) ? $key : $value;
						$selected = '';
						if($field_value === $key){
							$selected = 'selected="selected"';
						}
						$field_html .= '<option value="'.$key.'" '.$selected.'>'.$value.'</option>';
					}
				$field_html .= '</select>';
				break;
			}
			case 'textarea': {
				$field_html = '<textarea name="'.$field_id.'" id="'.$field_id.'" rows="6">'.$field_value.'</textarea>';
				break;
			}
			default: {
				$field_html = "<input type='{$field['type']}' id='$field_id' name='$field_id' value='$field_value' />";
				break;
			}
		}
	
		return $field_html;
	}
	
	// Called when the taxonomy is saved.
	// Save the new meta values for our taxonomy.
	public function wpturbo_save_meta_fields($term_id){
		foreach ( $this->fields as $field_id => $field ) {
			if( isset($_POST[$field_id]) ){
				// Sanitize fields that need to be sanitized.
				switch($field['type']){
					case 'email': {
						$_POST[$field_id] = sanitize_email($_POST[$field_id]);
						break;
					}
					case 'text': {
						$_POST[$field_id] = sanitize_text_field($_POST[$field_id]);
						break;
					}
				}
				update_term_meta( $term_id, $field_id, $_POST[$field_id] );
			}
		}
	}
	
}

if (class_exists('wpturbo_CustomTermMeta')) {
	new wpturbo_CustomTermMeta();
}