<?php
// This file is part of
//
// 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/>.

function create_submission ($data, $gradeimporterid, $userid) {
    global $DB;
    $timenow = time();
    if (empty($data->id)) {
        // If is new db entry;
        $data->gradeimporterid = $gradeimporterid;
        $data->usermodified = $userid;
        $data->timecreated = $timenow;

        $isnewentry = true;
    } else {
        $isnewentry = false;
    }

    $data->descriptionformat = $data->description["format"];
    $data->description = $data->description["text"];
    $data->timemodified = $timenow;
    $data->position = -1; // Do later

    if ($isnewentry) {
        // If is new entry insert data into DB and gets id
        $data->id = $DB->insert_record('gradeimporter_submission', $data);
    }

    // If not new entry updates information
    // If new entry inserts id into DB
    $DB->update_record('gradeimporter_submission', $data);

    return $data;
}


function store_files ($context, $cm, $data) {
    global $CFG;
    $fs = get_file_storage();
    $files = $fs->get_area_files($context->id, 'mod_gradeimporter',
                                'submissionfiles', $data->id
                            );
    foreach ($files as $file) {
        if ($file->get_mimetype() == 'text/csv') {
            read_csv($file->get_content(), $context, $data);
            return;
        }
        if ($file->get_mimetype() == 'application/zip') {
            // If it is a .zip file, extract files from the zip
            $zipfiles = read_zip($file, $context, $fs);
            // Search a .csv file
            foreach ($zipfiles as $file) {

                if ($file->get_mimetype() == 'text/csv') {
                    // If csv is found, pass it to read_csv()
                    read_csv($file->get_content(), $context, $data, $zipfiles);
                    // Only expects one csv so doesn't look for another
                }
            }
            // Finished processing files from zip, so delete temp copies
            $fs->delete_area_files($context->id, 'mod_gradeimporter', 'unpacktemp', 0);
        }
    }
}

function read_csv ($content, $context, $data, $zipfiles = null) {

    $csv = prepare_csv($content);
    foreach ($csv as $feedback) {
        $feedbackid = store_feedback($feedback, $context->id, $data->id);
        if ($feedback['file'] != "") {
            // If feedback has associated file, insert it into pluginfile
            foreach ($zipfiles as $file) {
                // Search in zipfiles to find same name then feedback['file']
                if ($feedback['file'] == $file->get_filename()) {
                    $feedbackfileinfo = store_feedback_file($feedback, $context, $data, $file, $feedbackid);
                    break;
                }
            }
            // Already used all files, so delete extra copies

        }

    }
}

function prepare_csv ($content) {
    $csvlines = explode(PHP_EOL, $content);
    $csv = array();
    foreach ($csvlines as $line) {
        $csv[] = str_getcsv($line);
    }
    $header = array_shift($csv);

    $outputcsv = array();
    $outputcsv = array_map(
                            function($v)use($header){
                                return array_combine($header, $v);
                            },
                            $csv
                        );

    return $outputcsv;
}

function store_feedback ($feedback, $contextid, $submissionid) {
    global $DB;
    // Prepare data to submit to gradeimporter_feedback table
    $entry = new stdClass();
    $entry->id = null;

    $entry->timecreated = time();
    $entry->timemodified = time();

    $entry->submissionid = $submissionid;
    $entry->studentid = $feedback['id'];
    $entry->grade = $feedback['grade'];
    $entry->comment = $feedback['comment'];
    $entry->name = $feedback['file'];
    $entry->fileid = 0;
    $entry->usermodified = 1;
    $entry->contextid = $contextid;

    // Insert data into gradeimporter_feedback table and gets ID
    $entry->id = $DB->insert_record('gradeimporter_feedback', $entry);

}

function store_feedback_file ($feedback, $context, $submission, $filetostore, $feedbackid) {
    // Prepare file
    $fs = get_file_storage();
    $fileinfo = array(
        'contextid' => $context->id,
        'component' => 'mod_gradeimporter',
        'filearea' => 'submissionfiles',
        'itemid' => 0,
        'filepath' => "/",
        'filename' => $filetostore->get_filename(),
        'timecreated' => time(), 'timemodified' => time()
    );

    $fileinfo = $fs->create_file_from_storedfile($fileinfo, $filetostore);

    return $fileinfo;
}

function read_zip ($file, $context, $fs) {
    global $CFG;
    // Get file packer to unpack zip
    $packer = get_file_packer('application/zip');

    // Clear area_files if it has been used before
    $fs->delete_area_files($context->id,
                            'mod_gradeimporter',
                            'unpacktemp'
                        );

    // Extract to temp areafiles
    $file->extract_to_storage($packer,
                                $context->id,
                                'mod_gradeimporter',
                                'unpacktemp',
                                0,
                                $CFG->tempdir,
                                false
                            );

    // Get extracted files from unpacktemp area file
    $tempfiles = $fs->get_area_files($context->id,
                                    'mod_gradeimporter',
                                    'unpacktemp'
                        );

    // Returns an array of files object
    return $tempfiles;
}

function get_types_array($gradeimporterid) {
    global $DB, $CFG;
    // Gets moodle table prefix, usually mdl_
    $tp = $CFG->prefix;
    $query = "select id, name from {$tp}gradeimporter_submissiontype where gradeimporterid = $gradeimporterid";
    return $DB->get_records_sql($query);
}