<?php
@session_start();
require_once(__DIR__ . "/db_info.inc.php");

if (!(isset($_SESSION[$OJ_NAME . '_' . 'administrator'])
      || isset($_SESSION[$OJ_NAME . '_' . 'problem_editor'])
      || isset($_SESSION[$OJ_NAME . '_' . 'contest_creator']))) {
    echo "<a href='../loginpage.php'>Please Login First!</a>";
    exit(1);
}

$savePath = realpath(__DIR__ . '/../upload/') . '/';
$saveUrl = dirname(dirname($_SERVER['PHP_SELF'])) . '/upload/';
$extMap = array(
    'image' => array('gif', 'jpg', 'jpeg', 'png', 'bmp'),
    'flash' => array('swf', 'flv'),
    'media' => array('swf', 'flv', 'mp3', 'wav', 'wma', 'wmv', 'mid', 'avi', 'mpg', 'asf', 'rm', 'rmvb', 'mp4'),
    'file' => array('pdf', 'doc', 'docx', 'xls', 'xlsx', 'ppt', 'htm', 'html', 'txt', 'zip', 'rar', 'gz', 'bz2'),
);
$maxSize = 400 * 1024 * 1024;

if (!empty($_FILES['imgFile']['error'])) {
    switch ($_FILES['imgFile']['error']) {
        case '1':
            upload_error('超过php.ini允许的大小。');
            break;
        case '2':
            upload_error('超过表单允许的大小。');
            break;
        case '3':
            upload_error('图片只有部分被上传。');
            break;
        case '4':
            upload_error('请选择图片。');
            break;
        case '6':
            upload_error('找不到临时目录。');
            break;
        case '7':
            upload_error('写文件到硬盘出错。');
            break;
        case '8':
            upload_error('File upload stopped by extension。');
            break;
        case '999':
        default:
            upload_error('未知错误。');
            break;
    }
}

if (!empty($_FILES)) {
    $fileName = $_FILES['imgFile']['name'];
    $tmpName = $_FILES['imgFile']['tmp_name'];
    $fileSize = $_FILES['imgFile']['size'];

    if (!$fileName) {
        upload_error('请选择文件。');
    }
    if (@is_dir($savePath) === false) {
        upload_error('上传目录不存在。');
    }
    if (@is_writable($savePath) === false) {
        upload_error("上传目录没有写权限。在服务器上执行下述命令解决该问题:\n chown www-data -R \"$savePath\" \n");
    }
    if (@is_uploaded_file($tmpName) === false) {
        upload_error('上传失败。');
    }
    if ($fileSize > $maxSize) {
        upload_error('上传文件大小超过限制。');
    }

    $tempArr = explode('.', $fileName);
    $fileExt = strtolower(trim(array_pop($tempArr)));
    $dirName = '';

    foreach ($extMap as $key => $extensions) {
        if (in_array($fileExt, $extensions)) {
            $dirName = $key;
            break;
        }
    }

    if ($dirName === '') {
        $dirName = 'image';
    }
    if (empty($extMap[$dirName])) {
        upload_error('目录名不正确。');
    }
    if (in_array($fileExt, $extMap[$dirName]) === false) {
        upload_error('上传文件扩展名是不允许的扩展名。\n只允许' . implode(',', $extMap[$dirName]) . '格式。');
    }

    $savePath .= $dirName . '/';
    $saveUrl .= $dirName . '/';
    if (!file_exists($savePath)) {
        mkdir($savePath, 0744, true);
    }

    $ymd = date('Ymd');
    $savePath .= $ymd . '/';
    $saveUrl .= $ymd . '/';
    if (!file_exists($savePath)) {
        mkdir($savePath, 0744, true);
    }

    $newFileName = date('YmdHis') . '_' . rand(10000, 99999) . '.' . $fileExt;
    $filePath = $savePath . $newFileName;
    if (move_uploaded_file($tmpName, $filePath) === false) {
        upload_error('上传文件失败。');
    }
    @chmod($filePath, 0644);

    upload_success($saveUrl . $newFileName);
}

function upload_success($fileUrl) {
    header('Content-type: text/html; charset=UTF-8');
    echo json_encode(array('error' => 0, 'url' => $fileUrl), JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
    exit;
}

function upload_error($message) {
    header('Content-type: text/html; charset=UTF-8');
    echo json_encode(array('error' => 1, 'message' => $message), JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
    exit;
}