<?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/>.

/**
 * Prints a particular instance of sqlbox
 *
 * You can have a rather longer description of the file as well,
 * if you like, and it can span multiple lines.
 *
 * @package    mod
 * @subpackage sqlbox
 * @copyright  2012 Jan Klemkow, Benjamin Franzke
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

/// (Replace sqlbox with the name of your module and remove this line)

require_once(dirname(dirname(dirname(__FILE__))).'/config.php');
require_once(dirname(__FILE__).'/lib.php');
require_once(dirname(__FILE__).'/sqlbox_form.php');

$id = optional_param('id', 0, PARAM_INT); // course_module ID, or
$n  = optional_param('n', 0, PARAM_INT);  // sqlbox instance ID - it should be named as the first character of the module

if ($id) {
    $cm         = get_coursemodule_from_id('sqlbox', $id, 0, false, MUST_EXIST);
    $course     = $DB->get_record('course', array('id' => $cm->course), '*', MUST_EXIST);
    $sqlbox  = $DB->get_record('sqlbox', array('id' => $cm->instance), '*', MUST_EXIST);
} elseif ($n) {
    $sqlbox  = $DB->get_record('sqlbox', array('id' => $n), '*', MUST_EXIST);
    $course     = $DB->get_record('course', array('id' => $sqlbox->course), '*', MUST_EXIST);
    $cm         = get_coursemodule_from_instance('sqlbox', $sqlbox->id, $course->id, false, MUST_EXIST);
} else {
    error('You must specify a course_module ID or an instance ID');
}

require_login($course, true, $cm);
$context = get_context_instance(CONTEXT_MODULE, $cm->id);

add_to_log($course->id, 'sqlbox', 'view', "view.php?id={$cm->id}", $sqlbox->name, $cm->id);

/// Print the page header

$PAGE->set_url('/mod/sqlbox/view.php', array('id' => $cm->id));
$PAGE->set_title(format_string($sqlbox->name));
$PAGE->set_heading(format_string($course->fullname));
$PAGE->set_context($context);

// other things you may want to set - remove if not needed
//$PAGE->set_cacheable(false);
//$PAGE->set_focuscontrol('some-html-id');
//$PAGE->add_body_class('sqlbox-'.$somevar);

// Output starts here
echo $OUTPUT->header();

if ($sqlbox->intro) { // Conditions to show the intro can change to look for own settings or whatever
    echo $OUTPUT->box(format_module_intro('sqlbox', $sqlbox, $cm->id), 'generalbox mod_introbox', 'sqlboxintro');
}

// Replace the following lines with you own code

$form = new mod_sqlbox_form($PAGE->url->out(false));
$form->display();
$data = $form->get_data();

$correct = true;

echo $OUTPUT->heading('SQL Query: '.$data->sqlbox_query);
if (isset($data->sqlbox_query)) {
	$db = pg_connect("host=localhost dbname=sqlbox user=sqlbox password=foobar");
	if (!db)
		error("Failed to connect to sqlbox db");

	$table = db_get_table_from_query($db, $data->sqlbox_query);
	if (strlen($sqlbox->query) > 0) {
		$table_orig = db_get_table_from_query($db, $sqlbox->query);
		if ($table->data != $table_orig->data ||
		    $table->head != $table_orig->head) 
			$correct = false;
	}
	pg_close($db);

	echo html_writer::table($table);

	if ($correct)
		echo $OUTPUT->heading("Correct!");
	else
		echo $OUTPUT->heading("Incorrect!");
}

// Finish the page
echo $OUTPUT->footer();


function db_get_table_from_query($db, $query) {
	$table = new html_table;
	$result = pg_query($db, $query);
	if (!$result)
		error("Query failed: ".pg_last_error($db));

	$table = new html_table;
	$n = pg_num_fields($result);
	for ($i = 0; $i < $n; $i++)
		$table->head[] = pg_field_name($result, $i);
	$table->align = array_fill(0, $n, 'left');
	while ($row = pg_fetch_row($result))
		$table->data[] = $row;

	return $table;
}