<?php

    class Upload{
        protected $path='./upload/';//文件上传保存路径
        protected $allowSuffix = ['jpg','jpeg','gif','png','wbmp'];  //允许的后缀
        protected $allowMime = ['image/jpeg','image/png','image/wbmp','image/gif'];
        protected $maxSize =2000000;//允许文件大小
        protected $isRandName = true;//是否启动随机名
        protected $prefix = 'up_'; //文件前缀

        //错误号码错误信息
        protected $errorNumber;
        protected $errorInfo;

        //文件信息
        protected $oldName;//文件名
        protected $suffix;//文件的后缀
        protected $size;//文件的大小
        protected $mime;
        protected $tmpName;//临时文件的路径

        protected $newName ;//文件新名字


        public function __construct($arr=[]){
            foreach ($arr as $key => $value) {
                $this->setOption($key,$value);
            }
        }

        //判断这个$key是不是成员属性，如果是，则设置
        protected function setOption($key,$value){
            //得到所有的成员属性
            $keys = array_keys(get_class_vars(__CLASS__));
            //如果$key是成员属性，那么设置
            if(in_array($key, $keys)){
                $this->$key = $value;
            }

        }
        //文件上传函数
        //$key 就是input框中的name属性值
        public function uploadFile($key){
            //判断有没有设置路径 path
            if(empty($this->path)){
                $this->setOption('errorNumber',-1);
                return false;
            }
            //判断该目录是否存在，是否可写
            if(!$this->check()){
                $this->setOption('errorNumber',-2);
                return false;
            }

            //判断$_FILES里面的error信息是否为0

            $error = $_FILES[$key]['error'];
            if($error){
                $this->setOption('errorNumber',$error);
                return false;
            }else{
                //提取文件相关信息并且保存成员属性
                $this->getFileInfo($key);
            }
            //判断文件的大小、mime、后缀是否符合

            if(!$this->checkSize() || !$this->checkMime() || !$this->checkSuffix()){
                return false;
            }
            //得到新的文件名字
            $this->newName = $this->createNewName();
            //判断是否是上传文件，并且移动上传文件

            if(is_uploaded_file($this->tmpName)){
                if(move_uploaded_file($this->tmpName, $this->path.$this->newName)){
                        return $this->path.$this->newName;          
                }else{
                    $this->setOption('errorNumber',-7);
                }

            }else{
                $this->setOption('errorNumber',-6);
                return false;
            }

        }

        //得到文件的新名字
        protected function createNewName(){
            if($this->isRandName){
                $name = $this->prefix.uniqid().'.'.$this->suffix;
            }else{
                $name = $this->prefix.$this->oldName;
            }
            return $name;

        }

        protected function check(){
                //文件夹不存在或者不是目录，创建文件夹
                if(!file_exists($this->path) || !is_dir($this->path)){
                    return mkdir($this->path,0777,true);
                }

                //判断是否可写
                if(!is_writeable($this->path)){
                    return chmod($this->path, 0777);
                }
                return true;
            }

        protected function getFileInfo($key){
            //得到文件名字
            $this->oldName = $_FILES[$key]['name'];
            //得到文件的mime类型
            $this->mime = $_FILES[$key]['type'];
            //得到文件临时路径
            $this->tmpName  = $_FILES[$key]['tmp_name'];
            //得到文件大小
            $this->size = $_FILES[$key]['size'];
            //得到文件后缀
            $this->suffix = pathinfo($this->oldName)['extension'];
        }   

        protected function checkSize(){

            if($this->size > $this->maxSize){
                $this->setOption('errorNumber',-3);
                return false;
            }
            return true;
        }

        protected function checkMime(){
            if(!in_array($this->mime,$this->allowMime)){
                $this->setOption('errorNumber',-4);
                return false;
            }
            return true;
        }

        protected function checksuffix(){
            if(!in_array($this->suffix, $this->allowSuffix)){
                $this->setOption('errorNumber',-5);
                return false;
            }
            return true;
        }

        public function __get($name){
            if($name == 'errorNumber'){
                return $this->errorNumber;
            }else if($name == 'errorInfo'){
                return $this->getErrorInfo();
            }
        }
        protected function getErrorInfo(){
            switch ($this->errorNumber) {
                case -1:
                    $str = '文件路径没有设置';
                    break;
                case -2:
                    $str = '文件路径不是目录或者没有权限';
                    break;
                case -3:
                    $str = '文件大小超过指定范围';
                    break;
                case -4:
                    $str = '文件MIME不符合';
                    break;
                case -5:
                    $str = '文件后缀名不符合';
                    break;
                case -6:
                    $str = '不是上传文件';
                    break;
                case -7:
                    $str = '文件上传失败';
                    break;
                case 1:
                    $str = '超出php.ini设置大小';
                    break;
                case 2:
                    $str = '超出html表单大小';
                    break;
                case 3:
                    $str = '文件只有部分上传';
                    break;
                case 4:
                    $str = '没有文件上传';
                    break;
                
                case 6:
                    $str = '找不到临时文件';
                    break;
                case 7:
                    $str = '文件写入失败';
                    break;  
                
            }
            return $str;
        }
    }