exportlib.php

<?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/>.

/**
 * Export functions
 *
 * @package    block
 * @subpackage coursefeedback
 * @copyright  2011-2014 onwards Jan Eberhardt (@ innoCampus, TU Berlin)
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

defined("MOODLE_INTERNAL") || die();

require_once($CFG->dirroot . "/blocks/coursefeedback/lib.php");

class feedbackexport
{
	protected $course    = 0;
	protected $filetypes = array("csv");
	private $content     = "";
	private $format;

	public function __construct($course = 0, $seperator = "\t")
	{
		global $DB;

		if($DB->record_exists("course", array("id" => $course)))
			$this->course = $course;
		else
		{
			print_error("courseidnotfound", "error");
			exit(0);
		}
	}

	public function get_filetypes()
	{
		return $this->filetypes;
	}

	public function init_format($format)
	{
		if(in_array($format, $this->get_filetypes()))
		{
			$exportformatclass = "exportformat_" . $format;
			$this->format = new $exportformatclass();
			return true;
		}
		else
			return false;
	}

	public function create_file($lang)
	{
		global $CFG, $DB;

		if(!isset($this->format))
		{
			print_error("format not initialized", "block_coursefeedback");
		}
		else
		{
			$answers = block_coursefeedback_get_answers($this->course);
			$this->reset();
			$this->content = $this->format->build($answers, $lang);
		}
	}

	public function get_content()
	{
		return $this->content;
	}

	public function reset()
	{
		$this->content = "";
	}
}

/**
 * @author Jan Eberhardt
 * Generell format class. Doesn"t contain very much so far, but should provide basics.
 */
abstract class exportformat
{
	private $type = "unknown";

	public final function get_type()
	{
		return $this->type;
	}

	public abstract function build($arg1);
}

/**
 * @author Jan Eberhardt
 * CSV export class
 */
class exportformat_csv extends exportformat
{
	public $seperator;
	public $newline;
	public $quotes;

	/**
	 * Set CSV options.
	 *
	 * TODO Choosable values.
	 */
	public function __construct()
	{
		$this->type      = "csv";
		$this->seperator = ";";
		$this->newline   = "\n";
		$this->quotes    = "\"";
	}

	/**
	 * (non-PHPdoc)
	 * @see exportformat::build()
	 */
	public function build($answers, $lang = null)
	{
		global $DB;
		$config  = get_config("block_coursefeedback");
		$content = $this->quote(get_string("download_thead_questions", "block_coursefeedback"))
		         . $this->seperator
		         . $this->quote(get_string("table_html_abstain", "block_coursefeedback"));
		for ($i = 1; $i < 7; $i++)
			$content .= $this->seperator . $i;
		$content .= $this->newline;

		$lang = block_coursefeedback_find_language($lang);

		foreach ($answers as $questionid => $values)
		{
			$conditions = array("coursefeedbackid" => $config->active_feedback,
			                    "language" => $lang,
			                    "questionid" => $questionid);
			if($question = $DB->get_field("block_coursefeedback_questns", "question", $conditions));
			{
				$question = $this->quote(format_text(trim($question, " \""), FORMAT_PLAIN)) . $this->quotes;
				$content .= $question . $this->seperator . join($this->seperator, $values) . $this->newline;
			}
		}

		return $content;
	}

	/**
	 * Quotes a field value.
	 *
	 * @param string $str
	 * @return string
	 */
	private function quote($str)
	{
		return $this->quotes . $str . $this->quotes;
	}
}