/*
     * 生成水印logo
     * text 水印文字 bigImgPath 背景圖
     */
    public static function make_watermark_img($text, $bigImgPath)
    {
        if (strtoupper(substr(PHP_OS,0,3))==='WIN')
        {
            $font = "c:/windows/fonts/SIMHEI.TTF";//字型型別，這裡為黑體，
        }else{
            $font = "/usr/share/fonts/simhei.ttf";//
 
字型型別，這裡為黑體，
        }
        $text_len = strlen($text) / 3; //顯示的文字
        $width = $text_len * 17; //1個字17
        $logo = 'uploads/'.$text.'.png'; //水印文字圖片地址
        $size = 12; //字型大小
        $img = imagecreate($width,24);//建立一個長為x高為y的空白圖片
        imagecolorallocate($img,0xff,0xff,0xff);//設定圖片背景顏色，這裡背景顏色為#ffffff，也就是白色
 

        $black=imagecolorallocate($img,0x00,0x00,0x00);//設定字型顏色，這裡為#000000，也就是黑色
        imagettftext($img,$size,0,0,16, $black, $font , $text);//將ttf文字寫到圖片中
        $watermark_logo = imagepng($img, $logo);//輸出圖片，輸出png使用imagepng方法，輸出gif使用imagegif方法
        if (!$watermark_logo) {
            return ['status'=>false, 'msg' => '生成水印失敗'];
        }
        
 
//圖片旋轉
        self::flip($logo, $logo, 45);
        //新增水印
        $a = self::add_watermark($logo, $bigImgPath);
        print_r($a);die;
    }

    /*
     * 新增水印
     */
    public static function add_watermark($logo, $bigImgPath)
    {

        $im = imagecreatefromstring(file_get_contents($bigImgPath));
        //獲取水印源
        $watermark = imagecreatefromstring(file_get_contents($logo));
        //獲取圖、水印 寬高型別
        list($bgWidth, $bgHight, $bgType) = getimagesize($bigImgPath);
        list($logoWidth, $logoHight, $logoType) = getimagesize($logo);
        //定義平鋪資料
        $x_length = $bgWidth - 10; //x軸總長度
        $y_length = $bgHight - 10; //y軸總長度
        //建立透明畫布 偽白色
        $opacity = 30;
        $w = imagesx($watermark);
        $h = imagesy($watermark);
        $cut = imagecreatetruecolor($w,$h);
        $white = imagecolorallocatealpha($cut, 255,255,255,0);
        imagefill( $cut, 0, 0, $white );
        //整合水印
        imagecopy($cut, $watermark, 0, 0, 0, 0, $w, $h);
        //迴圈平鋪水印
        for ($x = 0; $x < $x_length; $x++)
        {
            for ($y = 0; $y < $y_length; $y++) {
                imagecopymerge($im, $cut, $x, $y, 0, 0, $logoWidth, $logoHight, $opacity);
                $y += $logoHight;
            }
            $x += $logoWidth;
        }
        header("Content-type:image/png");
        // imagejpeg 的第二個引數不傳, 預設是顯示圖片
        $keys = array_merge(range(0, 9), range('a', 'z'));
        $key = '';
        for ($i = 0; $i < 15; $i++) {
            $key .= $keys[array_rand($keys)];
        }
        $fileName = $key.time().'.png';
        $file_path = 'uploads/'.$fileName;
        $img =  imagepng($im);
        print_r($img);die;
    }

    /**
     * @param $filename // 圖片原始地址
     * @param $src // 旋轉後圖片儲存地址
     * @param int $degrees // 旋轉角度
     * @return bool
     */
    public static function flip($filename,$src,$degrees = 45)

    {
        //讀取圖片

        $data = @getimagesize($filename);

        if($data==false)return false;

        //讀取舊圖片

        switch ($data[2]) {
            case 1:

                $src_f = imagecreatefromgif($filename);break;

            case 2:

                $src_f = imagecreatefromjpeg($filename);break;

            case 3:

                $src_f = imagecreatefrompng($filename);break;

        }

        if($src_f=="")return false;

        $rotate = @imagerotate($src_f, $degrees,0);

        if(!imagejpeg($rotate,$src,100))return false;

        @imagedestroy($rotate);
        return true;
    }