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<?php
/**
* Thumbnail Generator 0.4 (Requires GD 2.0)
*/

class Image_Thumbnail extends Image_Abstract
{
	/** Source Dimensions */
	private $_srcImageX;
	private $_srcImageY;

	/** Destination Image */
	private $_dstImage;

	/** Destination Dimensions */
	private $_dstImageX;
	private $_dstImageY;

	/** Other Items */
	private $_originalFileLocation;
	private $_prefix;
	private $_suffix;
	private $_quality = 80;
	private $_pathInfo;
		
	/**
	* The file to create a thumbnail out of
	* @param string $filename The name (And Path if necessary) of the file
	*/
	public function setFile($filename) 
	{
		$this->_originalFileLocation = $filename;
		$this->_pathInfo = pathinfo($this->_originalFileLocation);
		$this->_originalFileExt = $this->_pathInfo['extension'];

		/** _ext might be overriden, it might not, but its used to compare in submit */
		$this->_ext = '.' . $this->_pathInfo['extension'];
		$this->_fileName = $this->_pathInfo['filename'];
		return $this;
	}
	
	/**
	* (Optional) Set the image quality for a JPEG, default is 80
	* @param integer $quality A value of 0 through 100
	*/
	public function setQuality($quality)
	{
		$this->_quality = (int) $quality;
		return $this;
	}
	
	/**
	* (Optional) Set a prefix for the image, default is 'th_'
	* @param string $prefix The prefix before the filename.
	*/
	public function setPrefix($prefix)
	{
		$this->_prefix = $prefix;
		$this->_fileName = $this->_prefix . $this->_fileName;
		return $this;
	}
	
	/**
	* (Optional) Set a suffix for the image, default is '_th'
	* @param string $suffix The suffix after the filename.
	*/
	public function setSuffix($suffix)
	{
		$this->_suffix = $suffix;
		$this->_fileName = $this->_fileName . $this->_suffix;
		return $this;
	}
	
	/**
	* (Optional) Makes the output become a format of choice.
	* @param string $ext The file extension: gif, jpg, png 
	*/
	public function setFormat($ext)
	{
		/** Strip the period if there is one */
		$this->_ext = trim(strtolower($ext)); 

		$types = array('.jpg', 'jpeg', '.gif', '.png');
		if (!in_array($this->_ext, $types)) 
		throw new Exception('Your file format must be: ' . implode(', ', $types));
		
		return $this;
	}
	
	/**
	 * This moves the file to a destination - It must be set BEFORE submitting!
	 * @param string $Dir The directory to move the new thumbnail to
	 */
	public function setDestination($dir)
	{
		// Handle these slashes the user might put in..
		$dir = ltrim($dir, '/');
		if (strpos($dir, -1) != '/') {
			$dir .= '/';
		}
		
		$this->_destination = $dir;
		return $this;
	}

	/**
	 * Set the thumbnail size,
	 *  Depending on the proportion of the image factor this in:
	 *		if the image is wider than the height, the X will match.
	 *  	if the image is taller than the width, the Y will match.
	 *
	 * @param <int> $x Desired width
	 * @param <int> $y Desired height
	 */
	public function setSize($x, $y)
	{
		$this->_getDimensions();
		
		$this->_canvasSizeX = (int) $x;
		$this->_canvasSizeY = (int) $y;
		$this->_dstImageX = (int) $x;
		$this->_dstImageY = (int) $y;

		/** 
		*	When a upload is way too tall or way too high, it doesn't resize properly,
		*	so we usually want to enable clipping, it's off by default
		*/
		
		/** Thanks to my brother Joe for helping me with math, I'm really bad! */
		/** If it's landscape */
		if ($this->_srcImageX > $this->_srcImageY) {
			$this->_dstImageX = ($this->_srcImageX * $this->_dstImageY) / $this->_srcImageY;
		}
		/** If it's portrait */
		if ($this->_srcImageX < $this->_srcImageY) {
			$this->_dstImageY = ($this->_srcImageY * $this->_dstImageX) / $this->_srcImageX;
		}
		
		return $this;
	}

	/**
	 * Runs the operation and outputs the image
	 */
	public function submit()
	{
		
		$this->_checkExists($this->_originalFileLocation);
		$this->_checkSet($this->_dstImageX);
		$this->_checkSet($this->_dstImageY);
		
		$this->_submitCalled = true;
		
		/** Create a new blank image */
		$this->_dstImage = imageCreateTrueColor($this->_canvasSizeX, $this->_canvasSizeY);

		/** Copy the resampled image onto the blank */
		imageCopyResampled($this->_dstImage, $this->_srcImage, 0, 0, 0, 0, $this->_dstImageX, $this->_dstImageY, $this->_srcImageX, $this->_srcImageY);
		//imageCopyResampled($this->_dstImage, $this->_srcImage, 0, 0, 0, 0, 100, 100, $this->_srcImageX, $this->_srcImageY);

		/** Save the file, also allow the result to be grabbed from a var */
		switch ($this->_ext)
		{
			case '.jpg':
			case '.jpeg':
				imageJPEG($this->_dstImage, $this->_fileName . $this->_ext, $this->_quality);
				break;
			case '.png':
				imagePNG($this->_dstImage, $this->_fileName . $this->_ext, 0, NULL);
				break;
			case '.gif':
				imageGIF($this->_dstImage, $this->_fileName . $this->_ext, $this->_quality);
				break;
		}
		
		/** If we need to move the location */
		if (isset($this->_destination))
		{
			$wasMoved = rename($this->_fileName . $this->_ext, $this->_destination . $this->_fileName . $this->_ext);

			/** If moving it fails, delete the thumnail */
			if ($wasMoved == false)
			{
				throw new Exception("The thumbnail was created, but it couldnt be moved because
				your folder: {$this->_destination} is not writable, so the thumbnail was erased
				so you can give your directory CHMOD 0777 permission.");

				$this->delete();
			}
		}
			
		/** Finishing by removing from memory */
		@imageDestroy($this->_srcImage);
		@imageDestroy($this->_dstImage);

	}
	
	/**
	 * Grabs the image dimensions
	 */
	private function _getDimensions()
	{
		/** Grab the Source Dimensions */
		switch ($this->_originalFileExt)
		{
			case 'jpg':
			case 'jpeg':
				$this->_srcImage = imageCreateFromJPEG($this->_originalFileLocation);
				break;
			case 'png':
				$this->_srcImage = imageCreateFromPNG($this->_originalFileLocation);
				imageAlphaBlending($this->_srcImage, false); // setting alpha blending on
				imageSaveAlpha($this->_srcImage, true); // save alphablending setting (important)
				break;
			case 'gif':
				$this->_srcImage = imageCreateFromGIF($this->_originalFileLocation);
				break;
		}
		
		$this->_srcImageX = imagesX($this->_srcImage);
		$this->_srcImageY = imagesY($this->_srcImage);
	}
	
	/**
	 * Returns data about the uploaded file
	 * @return array
	 */
	public function get()
	{
	    if ($this->_submitCalled == true) 
	    {
			return array(
				'dir' => $this->_destination,
				'name' => $this->_fileName,
				'ext' => $this->_ext
			);
	    }
	    else 
	    {
			throw new Exception('You must call get() after you call submit()');
	    }

	}
	
	/**
	* (Optional) Deletes the file, use in a Catch statement
	*/
	public function delete()
	{
		if ($this->_submitCalled == true)
		{
			if (file_exists($this->_destination . $this->_fileName . $this->_ext))
			@unlink($this->_destination . $this->_fileName . $this->_ext);
		}
	}


}