<?php
/* For licensing terms, see /license.txt */
/**
 * Search widget. Shows the search screen contents.
 */
require_once api_get_path(LIBRARY_PATH).'specific_fields_manager.lib.php';

/**
 * Add some required CSS and JS to html's head.
 *
 * Note that $htmlHeadXtra should be passed by reference and not value,
 * otherwise this function will have no effect and your form will be broken.
 *
 * @param array $htmlHeadXtra A reference to the doc $htmlHeadXtra
 */
function search_widget_prepare(&$htmlHeadXtra)
{
    $htmlHeadXtra[] = '
    <!-- script type="text/javascript" src="'.api_get_path(WEB_LIBRARY_PATH).'javascript/jquery.autocomplete.js"></script -->
    <script type="text/javascript" src="'.api_get_path(WEB_LIBRARY_PATH).'search/search_widget.js"></script>
    <link rel="stylesheet" type="text/css" href="'.api_get_path(WEB_LIBRARY_PATH).'javascript/jquery.autocomplete.css" />
    <link rel="stylesheet" type="text/css" href="'.api_get_path(WEB_LIBRARY_PATH).'search/search_widget.css" />';
}

/**
 * Get one term html select.
 */
function format_one_specific_field_select($prefix, $sf_term_array, $op, $extra_select_attr = 'size="7" class="sf-select-multiple"')
{
    global $charset;
    $multiple_select = '<select '.$extra_select_attr.' title="'.$prefix.'" id="sf-'.$prefix.'" name="sf_'.$prefix.'[]">';

    $all_selected = '';
    if (!empty($_REQUEST['sf_'.$prefix])) {
        if (in_array('__all__', $_REQUEST['sf_'.$prefix])) {
            $all_selected = 'selected="selected"';
        }
    }
    if ('and' == $op) {
        $all_selected_name = get_lang('All');
    } elseif ('or' == $op) {
        $all_selected_name = get_lang('Any');
    }
    $multiple_select .= '<option value="__all__" '.$all_selected.' >-- '.$all_selected_name.' --</option>';

    foreach ($sf_term_array as $raw_term) {
        $term = substr($raw_term, 1);
        if (empty($term)) {
            continue;
        }
        $html_term = htmlspecialchars($term, ENT_QUOTES, $charset);
        $selected = '';
        if (!empty($_REQUEST['sf_'.$prefix]) && is_array($_REQUEST['sf_'.$prefix]) && in_array($term, $_REQUEST['sf_'.$prefix])) {
            $selected = 'selected="selected"';
        }
        $multiple_select .= '<option value="'.$html_term.'" '.$selected.'>'.$html_term.'</option>';
    }
    $multiple_select .= '</select>';

    return $multiple_select;
}

/**
 * Get terms html selects.
 */
function format_specific_fields_selects($sf_terms, $op, $prefilter_prefix = '')
{
    // Process each prefix type term
    $i = 0;
    $max = count($sf_terms);
    $multiple_selects = '';
    foreach ($sf_terms as $prefix => $sf_term_array) {
        if ($prefix == $prefilter_prefix) {
            continue;
        }
        $multiple_select = '';
        if ($i > 0) {
            //print "+" image
            $multiple_select .= '<td><img class="sf-select-splitter" src="../img/search-big-plus.gif" alt="plus-sign-decoration"/></td>';
        }
        //sorting the array of terms
        $temp = [];
        if (!empty($sf_term_array)) {
            foreach ($sf_term_array as $key => $value) {
                $temp[trim(stripslashes($value['name']))] = $key;
            }
        }
        $temp = array_flip($temp);
        unset($sf_term_array);
        natcasesort($temp);
        $sf_term_array = $temp;

        $sf_copy = $sf_term_array;
        // get specific field name
        $sf_value = get_specific_field_list(['code' => "'$prefix'"]);
        $sf_value = array_shift($sf_value);
        $multiple_select .= '<td><label class="sf-select-multiple-title" for="sf_'.$prefix.'[]">'.$sf_value['name'].'</label><br />';
        $multiple_select .= format_one_specific_field_select($prefix, $sf_term_array, $op, 'multiple="multiple" size="7" class="sf-select-multiple"');
        $multiple_select .= '</td>';
        $multiple_selects .= $multiple_select;
        $i++;
    }

    return $multiple_selects;
}

/**
 * Build the normal form.
 *
 * First, natural way.
 */
function search_widget_normal_form($action, $show_thesaurus, $sf_terms, $op)
{
    $thesaurus_icon = Display::return_icon('thesaurus.gif', get_lang('Advanced search options'), ['id' => 'thesaurus-icon']);
    $advanced_options = '<a id="tags-toggle" href="#">'.get_lang('Advanced search options').'</a>';
    $display_thesaurus = (true == $show_thesaurus ? 'block' : 'none');
    $help = '<h3>'.get_lang('Keywords search help').'</h3>'.get_lang('Select keywords in one or more fields and click the search button.<br /><br />To select more than one keyword in a field, use Ctrl+click.');
    $mode = (!empty($_REQUEST['mode']) ? htmlentities($_REQUEST['mode']) : 'gallery');
    $type = (!empty($_REQUEST['type']) ? htmlentities($_REQUEST['type']) : 'normal');

    /**
     * POST avoid long urls, but we are using GET because
     * SortableTableFromArray pagination is done with simple links, so now we
     * could not send a form in pagination.
     */
    if (isset($_GET['action']) && 0 === strcmp(trim($_GET['action']), 'search')) {
        $action = 'index.php';
    }
    $navigator_info = api_get_navigator();

    if ('Internet Explorer' == $navigator_info['name'] && '6' == $navigator_info['version']) {
        $submit_button1 = '<input type="submit" id="submit" value="'.get_lang('Search').'" />';
        $submit_button2 = '<input class="lower-submit" type="submit" value="'.get_lang('Search').'" />';
        $reset_button = '<input type="submit" id="tags-clean" value="'.get_lang('Reset keywords').'" />';
    } else {
        $submit_button1 = '<button class="search" type="submit" id="submit" value="'.get_lang("Search").'" /> '.get_lang('Search').'</button>';
        $submit_button2 = '<button class="search" type="submit" value="'.get_lang('Search').'" />'.get_lang('Search').'</button>';
        $reset_button = '<button class="save"   type="submit" id="tags-clean" value="'.get_lang('Reset keywords').'" />'.get_lang('Reset keywords').'</button> ';
    }

    $query = isset($_REQUEST['query']) ? Security::remove_XSS($_REQUEST['query']) : null;

    $form = '<form id="chamilo_search" action="'.$action.'" method="GET">
            <input type="text" id="query" name="query" size="40" value="'.$query.'" />
            <input type="hidden" name="mode" value="'.$mode.'"/>
            <input type="hidden" name="type" value="'.$type.'"/>
            <input type="hidden" name="tablename_page_nr" value="1" />
            '.$submit_button1.'
            <br /><br />';
    $list = get_specific_field_list();

    if (!empty($list)) {
        $form .= '<span class="search-links-box">'.$advanced_options.'&nbsp;</span>
            <div id="tags" class="tags" style="display:'.$display_thesaurus.';">
                <div class="search-help-box">'.$help.'</div>
                <table>
                <tr>';
        $form .= format_specific_fields_selects($sf_terms, $op);
        $or_checked = '';
        $and_checked = '';
        if ('or' == $op) {
            $or_checked = 'checked="checked"';
        } elseif ('and' == $op) {
            $and_checked = 'checked="checked"';
        }
        $form .= '</tr>
                    <tr>
                        <td id="operator-select">
                            '.get_lang('Combine keywords with').':<br />
                            <input type="radio" class="search-operator" name="operator" value="or" '.$or_checked.'>'.api_strtoupper(get_lang('or')).'</input>
                            <input type="radio" class="search-operator" name="operator" value="and" '.$and_checked.'>'.api_strtoupper(get_lang('and')).'</input>
                        </td>
                        <td></td>
                        <td>
                            <br />
                          '.$reset_button.'
                            '.$submit_button2.'
                        </td>
                    </tr>
                    </table>
                </div>';
    }
    $form .= '</form>
    <br style="clear: both;"/>';

    return $form;
}

/**
 * Build the prefilter form.
 *
 * This type allow filter all other multiple select terms by one term in a dinamic way
 */
function search_widget_prefilter_form(
    $action,
    $show_thesaurus,
    $sf_terms,
    $op,
    $prefilter_prefix = null
) {
    $thesaurus_icon = Display::return_icon('thesaurus.gif', get_lang('Advanced search options'), ['id' => 'thesaurus-icon']);
    $advanced_options = '<a id="tags-toggle" href="#">'.get_lang('Advanced search options').'</a>';
    $display_thesaurus = (true == $show_thesaurus ? 'block' : 'none');
    $help = '<h3>'.get_lang('Keywords search help').'</h3>'.get_lang('Select keywords in one or more fields and click the search button.<br /><br />To select more than one keyword in a field, use Ctrl+click.');
    $mode = (!empty($_REQUEST['mode']) ? htmlentities($_REQUEST['mode']) : 'gallery');
    $type = (!empty($_REQUEST['type']) ? htmlentities($_REQUEST['type']) : 'normal');

    /**
     * POST avoid long urls, but we are using GET because
     * SortableTableFromArray pagination is done with simple links, so now we
     * could not send a form in pagination.
     */
    if (isset($_GET['action']) && 0 === strcmp(trim($_GET['action']), 'search')) {
        $action = 'index.php';
    }

    $form = '
        <form id="chamilo_search" action="'.$action.'" method="GET">
            <input type="text" id="query" name="query" size="40" />
            <input type="hidden" name="mode" value="'.$mode.'"/>
            <input type="hidden" name="type" value="'.$type.'"/>
            <input type="hidden" name="tablename_page_nr" value="1" />
            <input type="submit" id="submit" value="'.get_lang("Search").'" />
            <br /><br />';
    $list = get_specific_field_list();
    if (!empty($list)) {
        $form .= ' <span class="search-links-box">'.$thesaurus_icon.$advanced_options.'&nbsp;</span>
                <div id="tags" class="tags" style="display:'.$display_thesaurus.';">
                    <div class="search-help-box">'.$help.'</div>
                    <table>
                    <tr>';
        if (!is_null($prefilter_prefix)) {
            //sorting the array of terms
            $temp = [];
            foreach ($sf_terms[$prefilter_prefix] as $key => $value) {
                $temp[trim(stripslashes($value['name']))] = $key;
            }
            $temp = array_flip($temp);
            unset($sf_term_array);
            natcasesort($temp);
            $sf_term_array = $temp;

            // get specific field name
            $sf_value = get_specific_field_list(['code' => "'$prefilter_prefix'"]);
            $sf_value = array_shift($sf_value);
            $form .= '<label class="sf-select-multiple-title" for="sf_'.$prefix.'[]">'.$icons_for_search_terms[$prefix].' '.$sf_value['name'].'</label><br />';

            $form .= format_one_specific_field_select($prefilter_prefix, $sf_term_array, $op, 'id="prefilter"');
            $form .= format_specific_fields_selects($sf_terms, $op, $prefilter_prefix);
        } else {
            $form .= format_specific_fields_selects($sf_terms, $op);
        }
        $or_checked = '';
        $and_checked = '';
        if ('or' == $op) {
            $or_checked = 'checked="checked"';
        } elseif ('and' == $op) {
            $and_checked = 'checked="checked"';
        }
        $form .= '
                    </tr>
                    <tr>
                        <td id="operator-select">
                            '.get_lang('Combine keywords with').':<br />
                            <input type="radio" class="search-operator" name="operator" value="or" '.$or_checked.'>'.api_strtoupper(get_lang('or')).'</input>
                            <input type="radio" class="search-operator" name="operator" value="and" '.$and_checked.'>'.api_strtoupper(get_lang('and')).'</input>
                        </td>
                        <td></td>
                        <td>
                            <br />
                            <input class="lower-submit" type="submit" value="'.get_lang('Search').'" />
                            <input type="submit" id="tags-clean" value="'.get_lang('Reset keywords').'" />
                        </td>
                    </tr>
                    </table>
                </div>';
    }
    $form .= '
    </form>
    <br style="clear: both;"/>';

    return $form;
}

/**
 * Show search form.
 */
function display_search_form($action, $show_thesaurus, $sf_terms, $op)
{
    $type = (!empty($_REQUEST['type']) ? htmlentities($_REQUEST['type']) : 'normal');

    switch ($type) {
        case 'prefilter':
            $prefilter_prefix = api_get_setting('search_prefilter_prefix');
            $form = search_widget_prefilter_form(
                $action,
                $show_thesaurus,
                $sf_terms,
                $op,
                $prefilter_prefix
            );
            break;
        case 'normal':
        default:
            $form = search_widget_normal_form(
                $action,
                $show_thesaurus,
                $sf_terms,
                $op
            );
            break;
    }

    // show built form
    echo $form;
}

/**
 * Show the search widget.
 *
 * The form will post to index.php by default, you can pass a value to
 * $action to use a custom action.
 * IMPORTANT: you have to call search_widget_prepare() before calling this
 * function or otherwise the form will not behave correctly.
 *
 * @param string $action Just in case your action is not
 *                       index.php
 */
function search_widget_show($action = 'index.php')
{
    require_once api_get_path(LIBRARY_PATH).'search/ChamiloQuery.php';
    // TODO: load images dinamically when they're avalaible from specific field ui to add
    $groupId = api_get_group_id();

    $sf_terms = [];
    $specific_fields = get_specific_field_list();
    $url_params = [];

    if (-1 != ($cid = api_get_course_id())) { // with cid
        // get search engine terms
        $course_filter = chamilo_get_boolean_query(XAPIAN_PREFIX_COURSEID.$cid);
        $dkterms = chamilo_query_simple_query('', 0, 1000, [$course_filter]);

        //prepare specific fields names (and also get possible URL param names)
        foreach ($specific_fields as $specific_field) {
            $temp = [];
            if (is_array($dkterms) && count($dkterms) > 0) {
                foreach ($dkterms[1] as $obj) {
                    $temp = array_merge($obj['sf-'.$specific_field['code']], $temp);
                }
            }
            $sf_terms[$specific_field['code']] = $temp;
            $url_params[] = 'sf_'.$specific_field['code'];
            unset($temp);
        }
    } else { // without cid
        // prepare specific fields names (and also get possible URL param names)
        foreach ($specific_fields as $specific_field) {
            //get Xapian terms for a specific term prefix, in ISO, apparently
            $sf_terms[$specific_field['code']] = xapian_get_all_terms(1000, $specific_field['code']);
            $url_params[] = 'sf_'.$specific_field['code'];
        }
    }
    echo '<h2>'.get_lang('Search').'</h2>';

    // Tool introduction
    // TODO: Settings for the online editor to be checked (insert an image for example). Probably this is a special case here.
    if (-1 !== api_get_course_id()) {
        if (!empty($groupId)) {
            Display::display_introduction_section(TOOL_SEARCH.$groupId);
        } else {
            Display::display_introduction_section(TOOL_SEARCH);
        }
    }

    $op = 'or';
    if (!empty($_REQUEST['operator']) && in_array($op, ['or', 'and'])) {
        $op = $_REQUEST['operator'];
    }

    //check if URL params are defined (to see if we show the thesaurus or not)
    $show_thesaurus = false;
    foreach ($url_params as $param) {
        if (isset($_REQUEST[$param]) && is_array($_REQUEST[$param])) {
            $thesaurus_decided = false;
            foreach ($_REQUEST[$param] as $term) {
                if (!empty($term)) {
                    $show_thesaurus = true;
                    $thesaurus_decided = true;
                    break;
                }
            }
            if ($thesaurus_decided) {
                break;
            }
        }
    }

    // create the form
    // TODO: use FormValidator
    display_search_form($action, $show_thesaurus, $sf_terms, $op);
}
