<?php
//生成图像缩略图和生成验证码
class Image {
	//生成图像验证码
    static public function buildImageVerify($width=48,$height=22,$randval=NULL,$verifyName='verify') {
		if( !isset($_SESSION) ) {
			session_start();//如果没有开启，session，则开启session
		}		
		$randval =empty($randval)? ("".rand(1000,9999)):$randval;
		$_SESSION[$verifyName]= $randval;
		$length=4;
		$width = ($length*10+10)>$width?$length*10+10:$width;
		$im = imagecreate($width,$height);  
		$r = array(225,255,255,223);
		$g = array(225,236,237,255);
		$b = array(225,236,166,125);
		$key = mt_rand(0,3);
		
		$backColor = imagecolorallocate($im, $r[$key],$g[$key],$b[$key]);    //背景色（随机）
		$borderColor = imagecolorallocate($im, 100, 100, 100);                    //边框色
		$pointColor = imagecolorallocate($im,mt_rand(0,255),mt_rand(0,255),mt_rand(0,255));                 //点颜色
		
		@imagefilledrectangle($im, 0, 0, $width - 1, $height - 1, $backColor);
		@imagerectangle($im, 0, 0, $width-1, $height-1, $borderColor);
		$stringColor = imagecolorallocate($im,mt_rand(0,200),mt_rand(0,120),mt_rand(0,120));
		// 干扰
		for($i=0;$i<10;$i++){
			$fontcolor=imagecolorallocate($im,mt_rand(0,255),mt_rand(0,255),mt_rand(0,255));
			imagearc($im,mt_rand(-10,$width),mt_rand(-10,$height),mt_rand(30,300),mt_rand(20,200),55,44,$fontcolor);
		}
		for($i=0;$i<25;$i++){
			$fontcolor=imagecolorallocate($im,mt_rand(0,255),mt_rand(0,255),mt_rand(0,255));
			imagesetpixel($im,mt_rand(0,$width),mt_rand(0,$height),$pointColor);
		}
		for($i=0;$i<$length;$i++) {
			imagestring($im,5,$i*10+5,mt_rand(1,8),$randval{$i}, $stringColor);
		}
		self::output($im,'png');
    }
	
	//生成缩略图
    static public function thumb($image, $thumbname, $domain = 'public', $maxWidth=200, $maxHeight=50, $interlace=true) {
        // 获取原图信息
		$info  = self::getImageInfo($image);
		if($info !== false) {
			$srcWidth  = $info['width'];
			$srcHeight = $info['height'];
			$type = strtolower($info['type']);
			$interlace  =  $interlace? 1:0;
			unset($info);
			$scale = min($maxWidth/$srcWidth, $maxHeight/$srcHeight); // 计算缩放比例
			if($scale>=1) {  // 超过原图大小不再缩略
				$width   =  $srcWidth;
				$height  =  $srcHeight;
			} else {  // 缩略图尺寸
				$width  = (int)($srcWidth*$scale);
				$height = (int)($srcHeight*$scale);
			}
			
			//sae平台上图片处理
			if( class_exists('SaeStorage')) {
				$saeStorage = new SaeStorage();
				$saeImage = new SaeImage();
				$saeImage->setData( file_get_contents($image) );
				$saeImage->resize($width, $height);
				$thumbname = str_replace(array('../', './'), '', $thumbname);
				return $saeStorage->write( $domain, $thumbname, $saeImage->exec() );
			}	
				
			// 载入原图
			$createFun = 'ImageCreateFrom'.($type=='jpg'?'jpeg':$type);
			$srcImg     = $createFun($image);
			
			//创建缩略图
			if($type!='gif' && function_exists('imagecreatetruecolor')) {
				$thumbImg = imagecreatetruecolor($width, $height);
			} else {
				$thumbImg = imagecreate($width, $height);
			}
			// 复制图片
			if(function_exists("ImageCopyResampled")) {
				imagecopyresampled($thumbImg, $srcImg, 0, 0, 0, 0, $width, $height, $srcWidth,$srcHeight);
			} else {
				imagecopyresized($thumbImg, $srcImg, 0, 0, 0, 0, $width, $height,  $srcWidth,$srcHeight);
			}	
			if('gif'==$type || 'png'==$type) {
				$background_color  =  imagecolorallocate($thumbImg,  0,255,0);  //  指派一个绿色
				imagecolortransparent($thumbImg,$background_color);  //  设置为透明色，若注释掉该行则输出绿色的图
			}
			// 对jpeg图形设置隔行扫描
			if('jpg'==$type || 'jpeg'==$type) {
				 imageinterlace($thumbImg,$interlace);
			}
			$dir = dirname($thumbname);
			if ( !is_dir($dir) ) {
				@mkdir($dir, 0777, true);
			}
			// 生成图片
			$imageFun = 'image'.($type=='jpg'?'jpeg':$type);
			$imageFun($thumbImg,$thumbname);
			imagedestroy($thumbImg);
			imagedestroy($srcImg);
			return $thumbname;
         }
         return false;
    }
	
     /**
     * 图片水印
     * @$image  原图
     * @$water 水印图片
     * @$$waterPos 水印位置(0-9) 0为随机，其他代表上中下9个部分位置
     */
    static public function water($image, $water, $waterPos =9) {
	    //检查图片是否存在
        if (!file_exists($image) || !file_exists($water))
            return false;
	   //读取原图像文件
        $imageInfo = self::getImageInfo($image);
        $image_w = $imageInfo['width']; //取得水印图片的宽
        $image_h = $imageInfo['height']; //取得水印图片的高
        $imageFun = "imagecreatefrom" . $imageInfo['type'];
        $image_im = $imageFun($image);
        
        //读取水印文件
        $waterInfo = self::getImageInfo($water);
        $w = $water_w = $waterInfo['width']; //取得水印图片的宽
        $h = $water_h = $waterInfo['height']; //取得水印图片的高
        $waterFun = "imagecreatefrom" . $waterInfo['type'];
        $water_im = $waterFun($water);

        switch ($waterPos) {
            case 0: //随机
                $posX = rand(0, ($image_w - $w));
                $posY = rand(0, ($image_h - $h));
                break;
            case 1: //1为顶端居左
                $posX = 0;
                $posY = 0;
                break;
            case 2: //2为顶端居中
                $posX = ($image_w - $w) / 2;
                $posY = 0;
                break;
            case 3: //3为顶端居右
                $posX = $image_w - $w;
                $posY = 0;
                break;
            case 4: //4为中部居左
                $posX = 0;
                $posY = ($image_h - $h) / 2;
                break;
            case 5: //5为中部居中
                $posX = ($image_w - $w) / 2;
                $posY = ($image_h - $h) / 2;
                break;
            case 6: //6为中部居右
                $posX = $image_w - $w;
                $posY = ($image_h - $h) / 2;
                break;
            case 7: //7为底端居左
                $posX = 0;
                $posY = $image_h - $h;
                break;
            case 8: //8为底端居中
                $posX = ($image_w - $w) / 2;
                $posY = $image_h - $h;
                break;
            case 9: //9为底端居右
                $posX = $image_w - $w;
                $posY = $image_h - $h;
                break;
            default: //随机
                $posX = rand(0, ($image_w - $w));
                $posY = rand(0, ($image_h - $h));
                break;
        }
        //设定图像的混色模式        
        imagealphablending($image_im, true);
        imagecopy($image_im, $water_im, $posX, $posY, 0, 0, $water_w, $water_h); //拷贝水印到目标文件
        //生成水印后的图片
        $bulitImg = "image" . $imageInfo['type'];
        $bulitImg($image_im, $image);
        //释放内存
        $waterInfo = $imageInfo = null;
        imagedestroy($image_im);
    }

    static protected function getImageInfo($img) {
        $imageInfo = getimagesize($img);
        if( $imageInfo!== false) {
            $imageType = strtolower(substr(image_type_to_extension($imageInfo[2]),1));
            $imageSize = filesize($img);
            $info = array(
                "width"=>$imageInfo[0],
                "height"=>$imageInfo[1],
                "type"=>$imageType,
                "size"=>$imageSize,
                "mime"=>$imageInfo['mime']
            );
            return $info;
        } else {
            return false;
        }
    }
	
    static protected function output($im,$type='png',$filename='') {
		header("Content-type: image/".$type);
		$ImageFun='image'.$type;
		if(empty($filename)) {
			$ImageFun($im);
		}else{
			$ImageFun($im,$filename);
		}
		imagedestroy($im);
		exit;
    }
}
?>