<?php
/* vim: set expandtab tabstop=4 shiftwidth=4: */
// +----------------------------------------------------------------------+
// | PHP Version 4                                                        |
// +----------------------------------------------------------------------+
// | Copyright (c) 1997-2003 The PHP Group                                |
// +----------------------------------------------------------------------+
// | This source file is subject to version 2.0 of the PHP license,       |
// | that is bundled with this package in the file LICENSE, and is        |
// | available at through the world-wide-web at                           |
// | http://www.php.net/license/2_02.txt.                                 |
// | If you did not receive a copy of the PHP license and are unable to   |
// | obtain it through the world-wide-web, please send a note to          |
// | license@php.net so we can mail you a copy immediately.               |
// +----------------------------------------------------------------------+
// | Author:  Matteo Di Giovinazzo <matteodg@infinito.it>                 |
// |                                                                      |
// | For the JavaScript code thanks to Martin Honnen and                  |
// | Nicholas C. Zakas                                                    |
// | See:                                                                 |
// |      http://www.faqts.com/knowledge_base/view.phtml/aid/13562        |
// | and                                                                  |
// |      http://www.sitepoint.com/article/1220                           |
// +----------------------------------------------------------------------+
//
// $Id: autocomplete.php,v 1.2 2010/12/14 17:35:24 moodlerobot Exp $


require_once("HTML/QuickForm/text.php");


/**
 * Class to dynamically create an HTML input text element that
 * at every keypressed javascript event, check in an array of options
 * if there's a match and autocomplete the text in case of match.
 *
 * Ex:
 * $autocomplete =& $form->addElement('autocomplete', 'fruit', 'Favourite fruit:');
 * $options = array("Apple", "Orange", "Pear", "Strawberry");
 * $autocomplete->setOptions($options);
 *
 * @author       Matteo Di Giovinazzo <matteodg@infinito.it>
 */
class HTML_QuickForm_autocomplete extends HTML_QuickForm_text
{
    // {{{ properties

    /**
     * Options for the autocomplete input text element
     *
     * @var       array
     * @access    private
     */
    var $_options = array();

    /**
     * "One-time" javascript (containing functions), see bug #4611
     *
     * @var     string
     * @access  private
     */
    var $_js = '';

    // }}}
    // {{{ constructor

    /**
     * Class constructor
     *
     * @param     string    $elementName    (optional)Input field name attribute
     * @param     string    $elementLabel   (optional)Input field label in form
     * @param     array     $options        (optional)Autocomplete options
     * @param     mixed     $attributes     (optional)Either a typical HTML attribute string
     *                                      or an associative array. Date format is passed along the attributes.
     * @access    public
     * @return    void
     */
    function HTML_QuickForm_autocomplete($elementName = null, $elementLabel = null, $options = null, $attributes = null)
    {
        $this->HTML_QuickForm_text($elementName, $elementLabel, $attributes);
        $this->_persistantFreeze = true;
        $this->_type = 'autocomplete';
        if (isset($options)) {
            $this->setOptions($options);
        }
    } //end constructor

    // }}}
    // {{{ setOptions()

    /**
     * Sets the options for the autocomplete input text element
     *
     * @param     array    $options    Array of options for the autocomplete input text element
     * @access    public
     * @return    void
     */
    function setOptions($options)
    {
        $this->_options = array_values($options);
    } // end func setOptions

    // }}}
    // {{{ toHtml()

    /**
     * Returns Html for the autocomplete input text element
     *
     * @access      public
     * @return      string
     */
    function toHtml()
    {
        // prevent problems with grouped elements
        $arrayName = str_replace(array('[', ']'), array('__', ''), $this->getName()) . '_values';

        $this->updateAttributes(array(
            'onkeypress' => 'return autocomplete(this, event, ' . $arrayName . ');'
        ));
        if ($this->_flagFrozen) {
            $js = '';
        } else {
            $js = "<script type=\"text/javascript\">\n//<![CDATA[\n";
            if (!defined('HTML_QUICKFORM_AUTOCOMPLETE_EXISTS')) {
                $this->_js .= <<<EOS

/* begin javascript for autocomplete */
function setSelectionRange(input, selectionStart, selectionEnd) {
    if (input.setSelectionRange) {
        input.setSelectionRange(selectionStart, selectionEnd);
    }
    else if (input.createTextRange) {
        var range = input.createTextRange();
        range.collapse(true);
        range.moveEnd("character", selectionEnd);
        range.moveStart("character", selectionStart);
        range.select();
    }
    input.focus();
}

function setCaretToPosition(input, position) {
    setSelectionRange(input, position, position);
}

function replaceSelection (input, replaceString) {
	var len = replaceString.length;
    if (input.setSelectionRange) {
        var selectionStart = input.selectionStart;
        var selectionEnd = input.selectionEnd;

        input.value = input.value.substring(0, selectionStart) + replaceString + input.value.substring(selectionEnd);
		input.selectionStart  = selectionStart + len;
		input.selectionEnd  = selectionStart + len;
    }
    else if (document.selection) {
        var range = document.selection.createRange();
		var saved_range = range.duplicate();

        if (range.parentElement() == input) {
            range.text = replaceString;
			range.moveEnd("character", saved_range.selectionStart + len);
			range.moveStart("character", saved_range.selectionStart + len);
			range.select();
        }
    }
    input.focus();
}


function autocompleteMatch (text, values) {
    for (var i = 0; i < values.length; i++) {
        if (values[i].toUpperCase().indexOf(text.toUpperCase()) == 0) {
            return values[i];
        }
    }

    return null;
}

function autocomplete(textbox, event, values) {
    if (textbox.setSelectionRange || textbox.createTextRange) {
        switch (event.keyCode) {
            case 38:    // up arrow
            case 40:    // down arrow
            case 37:    // left arrow
            case 39:    // right arrow
            case 33:    // page up
            case 34:    // page down
            case 36:    // home
            case 35:    // end
            case 13:    // enter
            case 9:     // tab
            case 27:    // esc
            case 16:    // shift
            case 17:    // ctrl
            case 18:    // alt
            case 20:    // caps lock
            case 8:     // backspace
            case 46:    // delete
                return true;
                break;

            default:
                var c = String.fromCharCode(
                    (event.charCode == undefined) ? event.keyCode : event.charCode
                );
                replaceSelection(textbox, c);
                sMatch = autocompleteMatch(textbox.value, values);
                var len = textbox.value.length;
				
                if (sMatch != null) {
                    textbox.value = sMatch;
                    setSelectionRange(textbox, len, textbox.value.length);
                }
                return false;
        }
    }
    else {
        return true;
    }
}
/* end javascript for autocomplete */

EOS;
                define('HTML_QUICKFORM_AUTOCOMPLETE_EXISTS', true);
            }
            $jsEscape = array(
                "\r"    => '\r',
                "\n"    => '\n',
                "\t"    => '\t',
                "'"     => "\\'",
                '"'     => '\"',
                '\\'    => '\\\\'
            );

            $js .= $this->_js;
            $js .= 'var ' . $arrayName . " = new Array();\n";
            for ($i = 0; $i < count($this->_options); $i++) {
                $js .= $arrayName . '[' . $i . "] = '" . strtr($this->_options[$i], $jsEscape) . "';\n";
            }
            $js .= "//]]>\n</script>";
        }
        return $js . parent::toHtml();
    }// end func toHtml

    // }}}
} // end class HTML_QuickForm_autocomplete
?>
