<?php
/* For licensing terms, see /license.txt */
/**
 * Library for the import of Aiken format
 * @author claro team <cvs@claroline.net>
 * @author Guillaume Lederer <guillaume@claroline.net>
 * @author César Perales <cesar.perales@gmail.com> Parse function for Aiken format
 * @package chamilo.exercise
 */

/**
 * This function displays the form for import of the zip file with qti2
 * @param   string  Report message to show in case of error
 */
function aiken_display_form()
{
    $name_tools = get_lang('ImportAikenQuiz');
    $form  = '<div class="actions">';
    $form .= '<a href="exercise.php?show=test&'.api_get_cidreq().'">'.
        Display::return_icon(
            'back.png',
            get_lang('BackToExercisesList'),
            '',
            ICON_SIZE_MEDIUM
        ).'</a>';
    $form .= '</div>';
    $form_validator = new FormValidator(
        'aiken_upload',
        'post',
        api_get_self()."?".api_get_cidreq(),
        null,
        array('enctype' => 'multipart/form-data')
    );
    $form_validator->addElement('header', $name_tools);
    $form_validator->addElement('text', 'total_weight', get_lang('TotalWeight'));
    $form_validator->addElement('file', 'userFile', get_lang('File'));
    $form_validator->addButtonUpload(get_lang('Upload'), 'submit');
    $form .= $form_validator->returnForm();
    $form .= '<blockquote>'.get_lang('ImportAikenQuizExplanation').'<br /><pre>'.get_lang('ImportAikenQuizExplanationExample').'</pre></blockquote>';
    echo $form;
}

/**
 * Gets the uploaded file (from $_FILES) and unzip it to the given directory
 * @param string The directory where to do the work
 * @param string The path of the temporary directory where the exercise was uploaded and unzipped
 * @param string $baseWorkDir
 * @param string $uploadPath
 * @return bool True on success, false on failure
 */
function get_and_unzip_uploaded_exercise($baseWorkDir, $uploadPath)
{
    $_course = api_get_course_info();
    $_user = api_get_user_info();

    // Check if the file is valid (not to big and exists)
    if (!isset($_FILES['userFile']) || !is_uploaded_file($_FILES['userFile']['tmp_name'])) {
        // upload failed
        return false;
    }

    if (preg_match('/.zip$/i', $_FILES['userFile']['name']) &&
        handle_uploaded_document(
            $_course,
            $_FILES['userFile'],
            $baseWorkDir,
            $uploadPath,
            $_user['user_id'],
            0,
            null,
            1,
            'overwrite',
            false
        )
    ) {
        if (!function_exists('gzopen')) {
            return false;
        }
        // upload successful
        return true;
    } elseif (preg_match('/.txt/i', $_FILES['userFile']['name']) &&
        handle_uploaded_document(
            $_course,
            $_FILES['userFile'],
            $baseWorkDir,
            $uploadPath,
            $_user['user_id'],
            0,
            null,
            0,
            'overwrite',
            false
        )
    ) {
        return true;
    } else {
        return false;
    }
}

/**
 * Main function to import the Aiken exercise
 * @param string $file
 * @return mixed True on success, error message on failure
 */
function aiken_import_exercise($file)
{
    $archive_path = api_get_path(SYS_ARCHIVE_PATH).'aiken/';
    $baseWorkDir = $archive_path;

    if (!is_dir($baseWorkDir)) {
        mkdir($baseWorkDir, api_get_permissions_for_new_directories(), true);
    }

    $uploadPath = 'aiken_'.api_get_unique_id().'/';

    // set some default values for the new exercise
    $exercise_info = array();
    $exercise_info['name'] = preg_replace('/.(zip|txt)$/i', '', $file);
    $exercise_info['question'] = array();

    // if file is not a .zip, then we cancel all
    if (!preg_match('/.(zip|txt)$/i', $file)) {
        return 'YouMustUploadAZipOrTxtFile';
    }

    // unzip the uploaded file in a tmp directory
    if (preg_match('/.(zip|txt)$/i', $file)) {
        if (!get_and_unzip_uploaded_exercise($baseWorkDir, $uploadPath)) {
            return 'ThereWasAProblemWithYourFile';
        }
    }

    // find the different manifests for each question and parse them
    $exerciseHandle = opendir($baseWorkDir.$uploadPath);
    $file_found = false;
    $operation = false;
    $result = false;

    // Parse every subdirectory to search txt question files
    while (false !== ($file = readdir($exerciseHandle))) {
        if (is_dir($baseWorkDir.'/'.$uploadPath.$file) && $file != "." && $file != "..") {
            //find each manifest for each question repository found
            $questionHandle = opendir($baseWorkDir.'/'.$uploadPath.$file);
            while (false !== ($questionFile = readdir($questionHandle))) {
                if (preg_match('/.txt$/i', $questionFile)) {
                    $result = aiken_parse_file(
                        $exercise_info,
                        $baseWorkDir,
                        $file,
                        $questionFile
                    );
                    $file_found = true;
                }
            }
        } elseif (preg_match('/.txt$/i', $file)) {
            $result = aiken_parse_file($exercise_info, $baseWorkDir.$uploadPath, '', $file);
            $file_found = true;
        }
    }

    if (!$file_found) {
        $result = 'NoTxtFileFoundInTheZip';
    }

    if ($result !== true) {
        return $result;
    }

    // 1. Create exercise
    $exercise = new Exercise();
    $exercise->exercise = $exercise_info['name'];

    $exercise->save();
    $last_exercise_id = $exercise->selectId();
    if (!empty($last_exercise_id)) {
        // For each question found...
        foreach ($exercise_info['question'] as $key => $question_array) {
            //2.create question
            $question = new Aiken2Question();
            $question->type = $question_array['type'];
            $question->setAnswer();
            $question->updateTitle($question_array['title']);

            if (isset($question_array['description'])) {
                $question->updateDescription($question_array['description']);
            }
            $type = $question->selectType();
            $question->type = constant($type);
            $question->save($last_exercise_id);
            $last_question_id = $question->selectId();
            //3. Create answer
            $answer = new Answer($last_question_id);
            $answer->new_nbrAnswers = count($question_array['answer']);
            $max_score = 0;

            foreach ($question_array['answer'] as $key => $answers) {
                $key++;
                $answer->new_answer[$key] = $answers['value'];
                $answer->new_position[$key] = $key;
                // Correct answers ...
                if (in_array($key, $question_array['correct_answers'])) {
                    $answer->new_correct[$key] = 1;
                    if (isset($question_array['feedback'])) {
                        $answer->new_comment[$key] = $question_array['feedback'];
                    }
                } else {
                    $answer->new_correct[$key] = 0;
                }

                if (isset($question_array['weighting'][$key - 1])) {
                    $answer->new_weighting[$key] = $question_array['weighting'][$key - 1];
                    $max_score += $question_array['weighting'][$key - 1];
                }
            }

            $answer->save();
            // Now that we know the question score, set it!
            $question->updateWeighting($max_score);
            $question->save();
        }

        // Delete the temp dir where the exercise was unzipped
        my_delete($baseWorkDir.$uploadPath);
        $operation = $last_exercise_id;
    }

    return $operation;
}

/**
 * Parses an Aiken file and builds an array of exercise + questions to be
 * imported by the import_exercise() function
 * @param array The reference to the array in which to store the questions
 * @param string Path to the directory with the file to be parsed (without final /)
 * @param string Name of the last directory part for the file (without /)
 * @param string Name of the file to be parsed (including extension)
 * @param string $exercisePath
 * @param string $file
 * @param string $questionFile
 * @return string|boolean True on success, error message on error
 * @assert ('','','') === false
 */
function aiken_parse_file(&$exercise_info, $exercisePath, $file, $questionFile)
{
    $questionTempDir = $exercisePath.'/'.$file.'/';
    $questionFilePath = $questionTempDir.$questionFile;

    if (!is_file($questionFilePath)) {
        return 'FileNotFound';
    }
    $data = file($questionFilePath);

    $question_index = 0;
    $correct_answer = '';
    $answers_array = array();
    $new_question = true;
    foreach ($data as $line => $info) {
        if ($question_index > 0 && $new_question == true && preg_match('/^(\r)?\n/', $info)) {
            // double empty line
            continue;
        }
        $new_question = false;
        //make sure it is transformed from iso-8859-1 to utf-8 if in that form
        if (!mb_check_encoding($info, 'utf-8') && mb_check_encoding($info, 'iso-8859-1')) {
            $info = utf8_encode($info);
        }
        $exercise_info['question'][$question_index]['type'] = 'MCUA';
        if (preg_match('/^([A-Za-z])(\)|\.)\s(.*)/', $info, $matches)) {
            //adding one of the possible answers
            $exercise_info['question'][$question_index]['answer'][]['value'] = $matches[3];
            $answers_array[] = $matches[1];
        } elseif (preg_match('/^ANSWER:\s?([A-Z])\s?/', $info, $matches)) {
            //the correct answers
            $correct_answer_index = array_search($matches[1], $answers_array);
            $exercise_info['question'][$question_index]['correct_answers'][] = $correct_answer_index + 1;
            //weight for correct answer
            $exercise_info['question'][$question_index]['weighting'][$correct_answer_index] = 1;
        } elseif (preg_match('/^ANSWER_EXPLANATION:\s?(.*)/', $info, $matches)) {
            //Comment of correct answer
            $correct_answer_index = array_search($matches[1], $answers_array);
            $exercise_info['question'][$question_index]['feedback'] = $matches[1];
        } elseif (preg_match('/^TEXTO_CORRECTA:\s?(.*)/', $info, $matches)) {
            //Comment of correct answer (Spanish e-ducativa format)
            $correct_answer_index = array_search($matches[1], $answers_array);
            $exercise_info['question'][$question_index]['feedback'] = $matches[1];
        } elseif (preg_match('/^T:\s?(.*)/', $info, $matches)) {
            //Question Title
            $correct_answer_index = array_search($matches[1], $answers_array);
            $exercise_info['question'][$question_index]['title'] = $matches[1];
        } elseif (preg_match('/^TAGS:\s?([A-Z])\s?/', $info, $matches)) {
             //TAGS for chamilo >= 1.10
            $exercise_info['question'][$question_index]['answer_tags'] = explode(',', $matches[1]);
        } elseif (preg_match('/^ETIQUETAS:\s?([A-Z])\s?/', $info, $matches)) {
            //TAGS for chamilo >= 1.10 (Spanish e-ducativa format)
            $exercise_info['question'][$question_index]['answer_tags'] = explode(',', $matches[1]);
        } elseif (preg_match('/^(\r)?\n/', $info)) {
            //moving to next question (tolerate \r\n or just \n)
            if (empty($exercise_info['question'][$question_index]['correct_answers'])) {
                error_log('Aiken: Error in question index '.$question_index.': no correct answer defined');
                return 'ExerciseAikenErrorNoCorrectAnswerDefined';
            }
            if (empty($exercise_info['question'][$question_index]['answer'])) {
                error_log('Aiken: Error in question index '.$question_index.': no answer option given');
                return 'ExerciseAikenErrorNoAnswerOptionGiven';
            }
            $question_index++;
            //emptying answers array when moving to next question
            $answers_array = array();
            $new_question = true;
        } else {
            if (empty($exercise_info['question'][$question_index]['title'])) {
                if (strlen($info) < 100) {
                    $exercise_info['question'][$question_index]['title'] = $info;
                } else {
                    //Question itself (use a 100-chars long title and a larger description)
                    $exercise_info['question'][$question_index]['title'] = trim(substr($info, 0, 100)).'...';
                    $exercise_info['question'][$question_index]['description'] = $info;
                }
            } else {
                $exercise_info['question'][$question_index]['description'] = $info;
            }
        }
    }
    $total_questions = count($exercise_info['question']);
    $total_weight = (!empty($_POST['total_weight'])) ? intval($_POST['total_weight']) : 20;
    foreach ($exercise_info['question'] as $key => $question) {
        $exercise_info['question'][$key]['weighting'][current(array_keys($exercise_info['question'][$key]['weighting']))] = $total_weight / $total_questions;
    }
    return true;
}

/**
 * Imports the zip file
 * @param array $array_file ($_FILES)
 * @return bool
 */
function aiken_import_file($array_file)
{
    $unzip = 0;
    $process = process_uploaded_file($array_file, false);
    if (preg_match('/\.(zip|txt)$/i', $array_file['name'])) {
        // if it's a zip, allow zip upload
        $unzip = 1;
    }

    if ($process && $unzip == 1) {
        $imported = aiken_import_exercise($array_file['name']);
        if (is_numeric($imported) && !empty($imported)) {
            Display::addFlash(Display::return_message(get_lang('Uploaded')));

            return $imported;

        } else {
            Display::addFlash(Display::return_message(get_lang($imported), 'error'));

            return false;
        }
    }
}