<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**
 * Allows to choose a form from the list of available templates
 *
 * @package    core_grades
 * @subpackage grading
 * @copyright  2011 David Mudrak <david@moodle.com>
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

require_once(dirname(dirname(dirname(__FILE__))).'/config.php');
require_once($CFG->dirroot.'/grade/grading/lib.php');
require_once($CFG->dirroot.'/grade/grading/pick_form.php');

$targetid   = required_param('targetid', PARAM_INT); // area we are coming from
$pick       = optional_param('pick', null, PARAM_INT); // create new form from this template
$remove     = optional_param('remove', null, PARAM_INT); // remove this template
$confirmed  = optional_param('confirmed', false, PARAM_BOOL); // is the action confirmed

// the manager of the target area
$targetmanager = get_grading_manager($targetid);

if ($targetmanager->get_context()->contextlevel < CONTEXT_COURSE) {
    throw new coding_exception('Unsupported gradable area context level');
}

// currently active method in the target area
$method = $targetmanager->get_active_method();
$targetcontroller = $targetmanager->get_controller($method);
$targetcontrollerclass = get_class($targetcontroller);

// make sure there is no such form defined in the target area
if ($targetcontroller->is_form_defined()) {
    redirect(new moodle_url('/grade/grading/manage.php', array('areaid' => $targetid)));
}

list($context, $course, $cm) = get_context_info_array($targetmanager->get_context()->id);

require_login($course, true, $cm);
require_capability('moodle/grade:managegradingforms', $context);

// user's capability in the templates bank
$canshare   = has_capability('moodle/grade:sharegradingforms', context_system::instance());
$canmanage  = has_capability('moodle/grade:managesharedforms', context_system::instance());

// setup the page
$PAGE->set_url(new moodle_url('/grade/grading/pick.php', array('targetid' => $targetid)));
navigation_node::override_active_url($targetmanager->get_management_url());
$PAGE->set_title(get_string('gradingmanagement', 'core_grading'));
$PAGE->set_heading(get_string('gradingmanagement', 'core_grading'));
$output = $PAGE->get_renderer('core_grading');

// process picking a template
if ($pick) {
    $sourceid = $DB->get_field('grading_definitions', 'areaid', array('id' => $pick), MUST_EXIST);
    $sourcemanager = get_grading_manager($sourceid);
    $sourcecontroller = $sourcemanager->get_controller($method);
    if (!$sourcecontroller->is_shared_template() and !$sourcecontroller->is_own_form()) {
        // note that we don't actually check whether the user has still the capability
        // moodle/grade:managegradingforms in the source area. so when users loose
        // their teacher role in a course, they can't access the course but they can
        // still copy the forms they have created there.
        throw new moodle_exception('attempt_to_pick_others_form', 'core_grading');
    }
    if (!$sourcecontroller->is_form_defined()) {
        throw new moodle_exception('form_definition_mismatch', 'core_grading');
    }
    $definition = $sourcecontroller->get_definition();
    if (!$confirmed) {
        echo $output->header();
        echo $output->confirm(get_string('templatepickconfirm', 'core_grading',array(
            'formname'  => s($definition->name),
            'component' => $targetmanager->get_component_title(),
            'area'      => $targetmanager->get_area_title())),
            new moodle_url($PAGE->url, array('pick' => $pick, 'confirmed' => 1)),
            $PAGE->url);
        echo $output->box($sourcecontroller->render_preview($PAGE), 'template-preview-confirm');
        echo $output->footer();
        die();
    } else {
        require_sesskey();
        $targetcontroller->update_definition($sourcecontroller->get_definition_copy($targetcontroller));
        $DB->set_field('grading_definitions', 'timecopied', time(), array('id' => $definition->id));
        redirect(new moodle_url('/grade/grading/manage.php', array('areaid' => $targetid)));
    }
}

// process removing a template
if ($remove) {
    $sourceid = $DB->get_field('grading_definitions', 'areaid', array('id' => $remove), MUST_EXIST);
    $sourcemanager = get_grading_manager($sourceid);
    $sourcecontroller = $sourcemanager->get_controller($method);
    if (!$sourcecontroller->is_shared_template()) {
        throw new moodle_exception('attempt_to_delete_nontemplate', 'core_grading');
    }
    if (!$sourcecontroller->is_form_defined()) {
        throw new moodle_exception('form_definition_mismatch', 'core_grading');
    }
    $definition = $sourcecontroller->get_definition();
    if ($canmanage or ($canshare and ($definition->usercreated == $USER->id))) {
        // ok, this user can drop the template
    } else {
        throw new moodle_exception('no_permission_to_remove_template', 'core_grading');
    }
    if (!$confirmed) {
        echo $output->header();
        echo $output->confirm(get_string('templatedeleteconfirm', 'core_grading', s($definition->name)),
            new moodle_url($PAGE->url, array('remove' => $remove, 'confirmed' => 1)),
            $PAGE->url);
        echo $output->box($sourcecontroller->render_preview($PAGE), 'template-preview-confirm');
        echo $output->footer();
        die();
    } else {
        require_sesskey();
        $sourcecontroller->delete_definition();
        redirect($PAGE->url);
    }
}

$searchform = new grading_search_template_form($PAGE->url, null, 'GET', '', array('class' => 'templatesearchform'));

if ($searchdata = $searchform->get_data()) {
    $tokens = grading_manager::tokenize($searchdata->needle);
    $includeownforms = (!empty($searchdata->mode));
} else {
    $tokens = array();
    $includeownforms = false;
}

// construct the SQL to find all matching templates
$sql = "SELECT DISTINCT gd.id, gd.areaid, gd.name, gd.usercreated
          FROM {grading_definitions} gd
          JOIN {grading_areas} ga ON (gd.areaid = ga.id)
          JOIN {context} cx ON (ga.contextid = cx.id)";
// join method-specific tables from the plugin scope
$sql .= $targetcontrollerclass::sql_search_from_tables('gd.id');

$sql .= " WHERE gd.method = ?";

$params = array($method);

if (!$includeownforms) {
    // search for public templates only
    $sql .= " AND ga.contextid = ? AND ga.component = 'core_grading'";
    $params[] = context_system::instance()->id;

} else {
    // search both templates and own forms in other areas
    $sql .= " AND ((ga.contextid = ? AND ga.component = 'core_grading')
                   OR (gd.usercreated = ? AND gd.status = ?))";
    $params = array_merge($params,  array(context_system::instance()->id, $USER->id,
        gradingform_controller::DEFINITION_STATUS_READY));
}

if ($tokens) {
    $subsql = array();

    // search for any of the tokens in the definition name
    foreach ($tokens as $token) {
        $subsql[] = $DB->sql_like('gd.name', '?', false, false);
        $params[] = '%'.$DB->sql_like_escape($token).'%';
    }

    // search for any of the tokens in the definition description
    foreach ($tokens as $token) {
        $subsql[] = $DB->sql_like('gd.description', '?', false, false);
        $params[] = '%'.$DB->sql_like_escape($token).'%';
    }

    // search for the needle in method-specific tables
    foreach ($tokens as $token) {
        list($methodsql, $methodparams) = $targetcontrollerclass::sql_search_where($token);
        $subsql = array_merge($subsql, $methodsql);
        $params = array_merge($params, $methodparams);
    }

    $sql .= " AND ((" . join(")\n OR (", $subsql) . "))";
}

$sql .= " ORDER BY gd.name";

$rs = $DB->get_recordset_sql($sql, $params);

echo $output->header();
$searchform->display();

$found = 0;
foreach ($rs as $template) {
    $found++;
    $out = '';
    $manager = get_grading_manager($template->areaid);
    $controller = $manager->get_controller($method);
    if ($controller->is_shared_template()) {
        $templatetag = html_writer::tag('span', get_string('templatetypeshared', 'core_grading'),
            array('class' => 'type shared'));
        $templatesrc  = '';
    } else if ($controller->is_own_form()) {
        $templatetag = html_writer::tag('span', get_string('templatetypeown', 'core_grading'),
            array('class' => 'type ownform'));
        $templatesrc  = get_string('templatesource', 'core_grading', array(
            'component' => $manager->get_component_title(),
            'area'      => $manager->get_area_title()));
    } else {
        throw new coding_exception('Something is wrong, the displayed form must be either template or own form');
    }
    $out .= $output->heading(s($template->name).' '.$templatetag, 2, 'template-name');
    $out .= $output->container($templatesrc, 'template-source');
    $out .= $output->box($controller->render_preview($PAGE), 'template-preview');
    $actions = array();
    if ($controller->is_shared_template()) {
        $actions[] = $output->pick_action_icon(new moodle_url($PAGE->url, array('pick' => $template->id)),
            get_string('templatepick', 'core_grading'), 'i/tick_green_big', 'pick template');
        if ($canmanage or ($canshare and ($template->usercreated == $USER->id))) {
            //$actions[] = $output->pick_action_icon(new moodle_url($PAGE->url, array('edit' => $template->id)),
            //    get_string('templateedit', 'core_grading'), 'i/edit', 'edit');
            $actions[] = $output->pick_action_icon(new moodle_url($PAGE->url, array('remove' => $template->id)),
                get_string('templatedelete', 'core_grading'), 't/delete', 'remove');
        }
    } else if ($controller->is_own_form()) {
        $actions[] = $output->pick_action_icon(new moodle_url($PAGE->url, array('pick' => $template->id)),
            get_string('templatepickownform', 'core_grading'), 'i/tick_green_big', 'pick ownform');
    }
    $out .= $output->box(join(' ', $actions), 'template-actions');
    $out .= $output->box($controller->get_formatted_description(), 'template-description');

    // ideally we should highlight just the name, description and the fields
    // in the preview that were actually searched. to make our life easier, we
    // simply highlight the tokens everywhere they appear, even if that exact
    // piece was not searched.
    echo highlight(join(' ', $tokens), $out);
}
$rs->close();

if (!$found) {
    echo $output->heading(get_string('nosharedformfound', 'core_grading'));
}

echo $output->single_button(
    new moodle_url('/grade/grading/manage.php', array('areaid' => $targetid)),
    get_string('back'), 'get');

echo $output->footer();

////////////////////////////////////////////////////////////////////////////////


