<?php
/**
 * Class Enum represents an enumeration of a set of strings.
 * See {@link DropdownField} for a {@link FormField} to select enum values.
 * 
 * @package sapphire
 * @subpackage model
 */
class Enum extends DBField {
	
	protected $enum, $default;
	
	public static $default_search_filter_class = 'ExactMatchFilter';
	
	/**
	 * Create a new Enum field.
	 * 
	 * Example usage in {@link DataObject::$db} with comma-separated string notation ('Val1' is default)
	 * <code>
	 *  "MyField" => "Enum('Val1, Val2, Val3', 'Val1')"
	 * </code>
	 * 
	 * Example usage in in {@link DataObject::$db} with array notation ('Val1' is default)
	 * <code>
	 * "MyField" => "Enum(array('Val1', 'Val2', 'Val3'), 'Val1')"
	 * </code>
	 * 
	 * @param enum: A string containing a comma separated list of options or an array of Vals.
	 * @param default The default option, which is either NULL or one of the items in the enumeration.
	 */
	function __construct($name, $enum = NULL, $default = NULL) {
		if($enum) {
			if(!is_array($enum)){
				$enum = preg_split("/ *, */", trim($enum));
			}

			$this->enum = $enum;
			
			// If there's a default, then 		
			if($default) {
				if(in_array($default, $enum)) {
					$this->default = $default;
				} else {
					user_error("Enum::__construct() The default value '$default' does not match any item in the enumeration", E_USER_ERROR);
				}
				
			// By default, set the default value to the first item
			} else {
				$this->default = reset($enum);
			}
		}
		parent::__construct($name);
	}
	
	function requireField(){
		$parts=Array('datatype'=>'enum', 'enums'=>$this->enum, 'character set'=>'utf8', 'collate'=> 'utf8_general_ci', 'default'=>$this->default, 'table'=>$this->tableName, 'arrayValue'=>$this->arrayValue);
		$values=Array('type'=>'enum', 'parts'=>$parts);
		DB::requireField($this->tableName, $this->name, $values);
}
	
	/**
	 * Return a dropdown field suitable for editing this field 
	 */
	function formField($title = null, $name = null, $hasEmpty = false, $value = "", $form = null, $emptyString = null) {
		if(!$title) $title = $this->name;
		if(!$name) $name = $this->name;

		$field = new DropdownField($name, $title, $this->enumValues($hasEmpty), $value, $form, $emptyString);
			
		return $field;		
	}

	public function scaffoldFormField($title = null, $params = null) {
		return $this->formField($title);
	}
	
	function scaffoldSearchField($title = null) {
		$anyText = _t('Enum.ANY', 'Any');
		return $this->formField($title, null, false, '', null, "($anyText)");
	}
	
	/**
	 * Return the values of this enum, suitable for insertion into a dropdown field.
	 */
	function enumValues($hasEmpty = false) {
		return ($hasEmpty) ? array_merge(array('' => ''), ArrayLib::valuekey($this->enum)) : ArrayLib::valuekey($this->enum);
	}
	
	function Lower() {
		return StringField::Lower();
	}
	function Upper() {
		return StringField::Upper();
	}
}

?>
