<?php 
class ComboboxHelper extends AppHelper {
	var $helpers = array('Html','Ajax','Javascript');
	
	/**
	 * Creates Combobox form input field.
	 * 
	 * This is a drop-in replacement for $ajax->autoComplete().
	 * The button image size is 'height' => 16, 'width' => 20.
	 *
	 * @param string $fieldId Same as Ajax->autoComplete()
	 * @param string $url Same as Ajax->autoComplete()
	 * @param array $options Same as Ajax->autoComplete(), except 'var' is not available.
	 * 		'comboboxTitle' - Optional title for the arrow button.
	 * 		'comboboxImage' - Optional arrow button image filename. default = 'combobox_arrow.gif'
	 * @return string HTML code
	 */
	function create($fieldId, $url, $options) {
		static $needs_javascript = true;
		
		if ($needs_javascript) {
			$this->Javascript->codeBlock('function comboboxButton(ac){ac.changed = false; ac.element.focus(); ac.hasFocus = true; var temp = ac.element.value; ac.element.value = ""; ac.getUpdatedChoices(); ac.element.value = temp; ac.tokenBounds = [-1, 0];}',
				array('inline' => false));
			$needs_javascript = false;
		}
		
		$options['var'] = Inflector::camelize(str_replace(".", "_", $fieldId)) . 'Combobox';
		
		$onclick = 'comboboxButton(' . $options['var'] . '); return false;';
		
		$title = null;
		if (isset($options['comboboxTitle'])) {
			$title = $options['comboboxTitle'];
			unset($options['comboboxTitle']);
		}
		
		$img = 'combobox_arrow.gif';
		if (isset($options['comboboxImage'])) {
			$img = $options['comboboxImage'];
			unset($options['comboboxImage']);
		}
		
		$ac = $this->Ajax->autoComplete($fieldId, $url, $options);
		
		$arrow = '/>' . $this->Html->image($img, compact('onclick','title'));
		
		// Have to do this because can't use 'after' option of $form->text()
		// because $ajax->autoComplete() passes 'after' option to Scriptaculous.
		return $this->output(str_replace('/>', $arrow, $ac));
	}
}
?>