<?php
/**
 * gd.thumbnail.inc.php
 *
 * @author      Ian Selby (ian@gen-x-design.com)
 * @copyright   Copyright 2006-2011
 * @version     1.3.0 (based on 1.1.3)
 * @modded      by Alex Rabe
 */

/**
 * PHP class for dynamically resizing, cropping, and rotating images for thumbnail purposes and either displaying them on-the-fly or saving them.
 */
class ngg_Thumbnail {
	/**
	 * Error message to display, if any
	 *
	 * @var string
	 */
	public $errmsg;
	/**
	 * Whether or not there is an error
	 *
	 * @var boolean
	 */
	public $error;
	/**
	 * Format of the image file
	 *
	 * @var string
	 */
	public $format;
	/**
	 * File name and path of the image file
	 *
	 * @var string
	 */
	public $fileName;
	/**
	 * Current dimensions of working image
	 *
	 * @var array
	 */
	public $currentDimensions;
	/**
	 * New dimensions of working image
	 *
	 * @var array
	 */
	public $newDimensions;
	/**
	 * Image resource for newly manipulated image
	 *
	 * @var resource
	 * @access private
	 */
	public $newImage;
	/**
	 * Image resource for image before previous manipulation
	 *
	 * @var resource
	 * @access private
	 */
	public $oldImage;
	/**
	 * Image resource for image being currently manipulated
	 *
	 * @var resource
	 * @access private
	 */
	public $workingImage;
	/**
	 * Percentage to resize image by
	 *
	 * @var int
	 * @access private
	 */
	public $percent;
	/**
	 * Maximum width of image during resize
	 *
	 * @var int
	 * @access private
	 */
	public $maxWidth;
	/**
	 * Maximum height of image during resize
	 *
	 * @var int
	 * @access private
	 */
	public $maxHeight;
	/**
	 * Image for Watermark
	 *
	 * @var string
	 */
	public $watermarkImgPath;
	/**
	 * Text for Watermark
	 *
	 * @var string
	 */
	public $watermarkText;

	public $newWidth;
	public $newHeight;

	/**
	 * Image Resource ID for Watermark
	 *
	 * @var string
	 */
	function __construct( $fileName, $no_ErrorImage = false ) {
		// make sure the GD library is installed
		if (!function_exists( "gd_info" )) {
			echo 'You do not have the GD Library installed.  This class requires the GD library to function properly.' . "\n";
			echo 'visit http://us2.php.net/manual/en/ref.image.php for more information';
			exit();
		}
		// initialize variables
		$this->errmsg            = '';
		$this->error             = false;
		$this->currentDimensions = array();
		$this->newDimensions     = array();
		$this->fileName          = $fileName;
		$this->percent           = 100;
		$this->maxWidth          = 0;
		$this->maxHeight         = 0;
		$this->watermarkImgPath  = '';
		$this->watermarkText     = '';

		// check to see if file exists
		if (!file_exists( $this->fileName )) {
			$this->errmsg = 'File not found';
			$this->error  = true;
		}
		// check to see if file is readable
		elseif (!is_readable( $this->fileName )) {
			$this->errmsg = 'File is not readable';
			$this->error  = true;
		}

		// if there are no errors, determine the file format
		if ($this->error == false) {
			@ini_set( 'memory_limit', -1 );

			$data = @getimagesize( $this->fileName );
			if (isset( $data ) && is_array( $data )) {
				$extensions = [
					IMAGETYPE_GIF  => 'GIF',
					IMAGETYPE_JPEG => 'JPG',
					IMAGETYPE_PNG  => 'PNG',
					IMAGETYPE_WEBP => 'WEBP',
				];
				$extension  = array_key_exists( $data[2], $extensions ) ?  $extensions[$data[2]] : '';
				if ($extension) {
					$this->format = $extension;
				} else {
					$this->errmsg = 'Unknown file format';
					$this->error  = true;
				}
			} else {
				$this->errmsg = 'File is not an image';
				$this->error  = true;
			}
		}

		// increase memory-limit if possible, GD needs this for large images
		// @ini_set('memory_limit', '128M');

		if ($this->error == false) {
			// Check memory consumption if file exists
			$this->checkMemoryForImage( $this->fileName );
		}

		// initialize resources if no errors
		if ($this->error == false) {

			switch ($this->format) {
				case 'GIF':
					$this->oldImage = ImageCreateFromGif( $this->fileName );
					break;
				case 'JPG':
						$this->oldImage = ImageCreateFromJpeg( $this->fileName );
					break;
				case 'PNG':
					$this->oldImage = ImageCreateFromPng( $this->fileName );
					break;
				case 'WEBP':
					$this->oldImage = imagecreatefromwebp( $this->fileName );
			}
			if (!$this->oldImage) {
				$this->errmsg = 'Create Image failed. Check memory limit';
				$this->error  = true;
			} else {
				$size                    = GetImageSize( $this->fileName );
				$this->currentDimensions = array( 'width'=>$size[0], 'height'=>$size[1] );
				$this->newImage          = $this->oldImage;
			}
		}

		if ($this->error == true) {
			if (!$no_ErrorImage) {
				$this->showErrorImage();
			}
			return;
		}
	}

	/**
	 * Calculate the memory limit
	 */
	function checkMemoryForImage( $filename ) {

		if ( ( function_exists( 'memory_get_usage' ) ) && ( ini_get( 'memory_limit' ) ) ) {
			$imageInfo = getimagesize( $filename );
			switch ($this->format) {
				case 'GIF':
					// measured factor 1 is better
					$CHANNEL = 1;
					break;
				case 'JPG':
					$CHANNEL = $imageInfo['channels'];
					break;
				case 'PNG':
					// didn't get the channel for png
					$CHANNEL = 3;
					break;
				case 'WEBP':
					$CHANNEL = $imageInfo['bits'];
					break;
			}
			$MB           = 1048576;  // number of bytes in 1M
			$K64          = 65536;    // number of bytes in 64K
			$TWEAKFACTOR  = 1.68;  // Or whatever works for you
			$memoryNeeded = round(
				( $imageInfo[0] * $imageInfo[1]
													* $imageInfo['bits']
													* $CHANNEL / 8
									+ $K64
									) * $TWEAKFACTOR
			);
			$memoryNeeded = memory_get_usage() + $memoryNeeded;
			// get memory limit
			$memory_limit = ini_get( 'memory_limit' );

			// PHP docs : Note that to have no memory limit, set this directive to -1.
			if ($memory_limit == -1 ) {
				return;
			}

			// Just check megabyte limits, not higher
			if ( strtolower( substr( $memory_limit, -1 ) ) == 'm' ) {

				if ($memory_limit != '') {
					$memory_limit = substr( $memory_limit, 0, -1 ) * 1024 * 1024;
				}

				if ($memoryNeeded > $memory_limit) {
					$memoryNeeded = round( $memoryNeeded / 1024 / 1024, 2 );
					$this->errmsg = 'Exceed Memory limit. Require : ' . $memoryNeeded . " MByte";
					$this->error  = true;
				}
			}
		}
		return;
	}

	/**
	 * Must be called to free up allocated memory after all manipulations are done
	 */
	function destruct() {
		if (is_resource( $this->newImage ) || $this->newImage instanceof GdImage) {
			@imagedestroy( $this->newImage );
		}

		if (is_resource( $this->oldImage ) || $this->oldImage instanceof GdImage) {
			@imagedestroy( $this->oldImage );
		}

		if (is_resource( $this->workingImage ) || $this->workingImage instanceof GdImage) {
			@imagedestroy( $this->workingImage );
		}
	}

	/**
	 * Returns the current width of the image
	 *
	 * @return int
	 */
	function getCurrentWidth() {
		return $this->currentDimensions['width'];
	}

	/**
	 * Returns the current height of the image
	 *
	 * @return int
	 */
	function getCurrentHeight() {
		return $this->currentDimensions['height'];
	}

	/**
	 * Calculates new image width
	 *
	 * @param int $width
	 * @param int $height
	 * @return array
	 */
	function calcWidth( $width, $height ) {
		$newWp     = ( 100 * $this->maxWidth ) / $width;
		$newHeight = ( $height * $newWp ) / 100;
		return array( 'newWidth'=>intval( $this->maxWidth ), 'newHeight'=>intval( $newHeight ) );
	}

	/**
	 * Calculates new image height
	 *
	 * @param int $width
	 * @param int $height
	 * @return array
	 */
	function calcHeight( $width, $height ) {
		$newHp    = ( 100 * $this->maxHeight ) / $height;
		$newWidth = ( $width * $newHp ) / 100;
		return array( 'newWidth'=>intval( $newWidth ), 'newHeight'=>intval( $this->maxHeight ) );
	}

	/**
	 * Calculates new image size based on percentage
	 *
	 * @param int $width
	 * @param int $height
	 * @return array
	 */
	function calcPercent( $width, $height ) {
		$newWidth  = ( $width * $this->percent ) / 100;
		$newHeight = ( $height * $this->percent ) / 100;
		return array( 'newWidth'=>intval( $newWidth ), 'newHeight'=>intval( $newHeight ) );
	}

	/**
	 * Calculates new image size based on width and height, while constraining to maxWidth and maxHeight
	 *
	 * @param int $width
	 * @param int $height
	 */
	function calcImageSize( $width, $height ) {
		$newSize = array( 'newWidth'=>$width, 'newHeight'=>$height );

		if ($this->maxWidth > 0) {

			$newSize = $this->calcWidth( $width, $height );

			if ($this->maxHeight > 0 && $newSize['newHeight'] > $this->maxHeight) {
				$newSize = $this->calcHeight( $newSize['newWidth'], $newSize['newHeight'] );
			}

			// $this->newDimensions = $newSize;
		}

		if ($this->maxHeight > 0) {
			$newSize = $this->calcHeight( $width, $height );

			if ($this->maxWidth > 0 && $newSize['newWidth'] > $this->maxWidth) {
				$newSize = $this->calcWidth( $newSize['newWidth'], $newSize['newHeight'] );
			}

			// $this->newDimensions = $newSize;
		}

		$this->newDimensions = $newSize;
	}

	/**
	 * Calculates new image size based percentage
	 *
	 * @param int $width
	 * @param int $height
	 */
	function calcImageSizePercent( $width, $height ) {
		if ($this->percent > 0) {
			$this->newDimensions = $this->calcPercent( $width, $height );
		}
	}

	/**
	 * Displays error image
	 */
	function showErrorImage() {
		header( 'Content-type: image/png' );
		$errImg   = ImageCreate( 220, 25 );
		$bgColor  = imagecolorallocate( $errImg, 0, 0, 0 );
		$fgColor1 = imagecolorallocate( $errImg, 255, 255, 255 );
		$fgColor2 = imagecolorallocate( $errImg, 255, 0, 0 );
		imagestring( $errImg, 3, 6, 6, 'Error:', $fgColor2 );
		imagestring( $errImg, 3, 55, 6, $this->errmsg, $fgColor1 );
		imagepng( $errImg );
		imagedestroy( $errImg );
	}

	/**
	 * Resizes image to fixed Width x Height
	 *
	 * @param int $Width
	 * @param int $Height
	 */
	function resizeFix( $Width = 0, $Height = 0, $deprecated = 3 ) {
		$this->newWidth  = $Width;
		$this->newHeight = $Height;

		if (function_exists( "ImageCreateTrueColor" )) {
			$this->workingImage = ImageCreateTrueColor( $this->newWidth, $this->newHeight );
		} else {
			$this->workingImage = ImageCreate( $this->newWidth, $this->newHeight );
		}

		// ImageCopyResampled(
		$this->imagecopyresampled(
			$this->workingImage,
			$this->oldImage,
			0,
			0,
			0,
			0,
			$this->newWidth,
			$this->newHeight,
			$this->currentDimensions['width'],
			$this->currentDimensions['height']
		);

		$this->oldImage                    = $this->workingImage;
		$this->newImage                    = $this->workingImage;
		$this->currentDimensions['width']  = $this->newWidth;
		$this->currentDimensions['height'] = $this->newHeight;
	}


	/**
	 * Resizes image to maxWidth x maxHeight
	 *
	 * @param int $maxWidth
	 * @param int $maxHeight
	 */
	function resize( $maxWidth = 0, $maxHeight = 0, $deprecated = 3 ) {
		$this->maxWidth  = $maxWidth;
		$this->maxHeight = $maxHeight;

		$this->calcImageSize( $this->currentDimensions['width'], $this->currentDimensions['height'] );

		if (function_exists( "ImageCreateTrueColor" )) {
			$this->workingImage = ImageCreateTrueColor( $this->newDimensions['newWidth'], $this->newDimensions['newHeight'] );
		} else {
			$this->workingImage = ImageCreate( $this->newDimensions['newWidth'], $this->newDimensions['newHeight'] );
		}

		// ImageCopyResampled(
		$this->imagecopyresampled(
			$this->workingImage,
			$this->oldImage,
			0,
			0,
			0,
			0,
			$this->newDimensions['newWidth'],
			$this->newDimensions['newHeight'],
			$this->currentDimensions['width'],
			$this->currentDimensions['height']
		);

		$this->oldImage                    = $this->workingImage;
		$this->newImage                    = $this->workingImage;
		$this->currentDimensions['width']  = $this->newDimensions['newWidth'];
		$this->currentDimensions['height'] = $this->newDimensions['newHeight'];
	}

	/**
	 * Resizes the image by $percent percent
	 *
	 * @param int $percent
	 */
	function resizePercent( $percent = 0 ) {
		$this->percent = $percent;

		$this->calcImageSizePercent( $this->currentDimensions['width'], $this->currentDimensions['height'] );

		if (function_exists( "ImageCreateTrueColor" )) {
			$this->workingImage = ImageCreateTrueColor( $this->newDimensions['newWidth'], $this->newDimensions['newHeight'] );
		} else {
			$this->workingImage = ImageCreate( $this->newDimensions['newWidth'], $this->newDimensions['newHeight'] );
		}

		$this->ImageCopyResampled(
			$this->workingImage,
			$this->oldImage,
			0,
			0,
			0,
			0,
			$this->newDimensions['newWidth'],
			$this->newDimensions['newHeight'],
			$this->currentDimensions['width'],
			$this->currentDimensions['height']
		);

		$this->oldImage                    = $this->workingImage;
		$this->newImage                    = $this->workingImage;
		$this->currentDimensions['width']  = $this->newDimensions['newWidth'];
		$this->currentDimensions['height'] = $this->newDimensions['newHeight'];
	}

	/**
	 * Crops the image from calculated center in a square of $cropSize pixels
	 *
	 * @param int $cropSize
	 */
	function cropFromCenter( $cropSize ) {
		if ($cropSize > $this->currentDimensions['width']) {
			$cropSize = $this->currentDimensions['width'];
		}
		if ($cropSize > $this->currentDimensions['height']) {
			$cropSize = $this->currentDimensions['height'];
		}

		$cropX = intval( ( $this->currentDimensions['width'] - $cropSize ) / 2 );
		$cropY = intval( ( $this->currentDimensions['height'] - $cropSize ) / 2 );

		if (function_exists( "ImageCreateTrueColor" )) {
			$this->workingImage = ImageCreateTrueColor( $cropSize, $cropSize );
		} else {
			$this->workingImage = ImageCreate( $cropSize, $cropSize );
		}

		$this->imagecopyresampled(
			$this->workingImage,
			$this->oldImage,
			0,
			0,
			$cropX,
			$cropY,
			$cropSize,
			$cropSize,
			$cropSize,
			$cropSize
		);

		$this->oldImage                    = $this->workingImage;
		$this->newImage                    = $this->workingImage;
		$this->currentDimensions['width']  = $cropSize;
		$this->currentDimensions['height'] = $cropSize;
	}

	/**
	 * Advanced cropping function that crops an image using $startX and $startY as the upper-left hand corner.
	 *
	 * @param int $startX
	 * @param int $startY
	 * @param int $width
	 * @param int $height
	 */
	function crop( $startX, $startY, $width, $height ) {
		// make sure the cropped area is not greater than the size of the image
		if ($width > $this->currentDimensions['width']) {
			$width = $this->currentDimensions['width'];
		}
		if ($height > $this->currentDimensions['height']) {
			$height = $this->currentDimensions['height'];
		}
		// make sure not starting outside the image
		if (( $startX + $width ) > $this->currentDimensions['width']) {
			$startX = ( $this->currentDimensions['width'] - $width );
		}
		if (( $startY + $height ) > $this->currentDimensions['height']) {
			$startY = ( $this->currentDimensions['height'] - $height );
		}
		if ($startX < 0) {
			$startX = 0;
		}
		if ($startY < 0) {
			$startY = 0;
		}

		if (function_exists( "ImageCreateTrueColor" )) {
			$this->workingImage = ImageCreateTrueColor( $width, $height );
		} else {
			$this->workingImage = ImageCreate( $width, $height );
		}

		$this->imagecopyresampled(
			$this->workingImage,
			$this->oldImage,
			0,
			0,
			$startX,
			$startY,
			$width,
			$height,
			$width,
			$height
		);

		$this->oldImage                    = $this->workingImage;
		$this->newImage                    = $this->workingImage;
		$this->currentDimensions['width']  = $width;
		$this->currentDimensions['height'] = $height;
	}

	/**
	 * Outputs the image to the screen, or saves to $name if supplied.  Quality of JPEG images can be controlled with the $quality variable
	 *
	 * @param int    $quality
	 * @param string $name
	 */
	function show( $quality = 100, $name = '' ) {
		switch ($this->format) {
			case 'GIF':
				if ($name != '') {
					@ImageGif( $this->newImage, $name ) or $this->error = true;
				} else {
					header( 'Content-type: image/gif' );
					ImageGif( $this->newImage );
				}
				break;
			case 'JPG':
				if ($name != '') {
					@ImageJpeg( $this->newImage, $name, $quality ) or $this->error = true;
				} else {
					header( 'Content-type: image/jpeg' );
					ImageJpeg( $this->newImage, null, $quality );
				}
				break;
			case 'PNG':
				if ($name != '') {
					@ImagePng( $this->newImage, $name ) or $this->error = true;
				} else {
					header( 'Content-type: image/png' );
					ImagePng( $this->newImage );
				}
				break;
			case 'WEBP':
				if ($name != '') {
					$this->error = !@imagewebp( $this->newImage, $name );
				} else {
					header( 'Content-type: image/webp' );
					imagewebp( $this->newImage );
				}
				break;
		}
	}

	/**
	 * Saves image as $name (can include file path), with quality of # percent if file is a jpeg
	 *
	 * @param string $name
	 * @param int    $quality
	 * @return bool errorstate
	 */
	function save( $name, $quality = 100 ) {
		$this->show( $quality, $name );
		if ($this->error == true) {
			$this->errmsg = 'Create Image failed. Check safe mode settings';
			return false;
		}

		if ( function_exists( 'do_action' ) ) {
			do_action( 'ngg_ajax_image_save', $name );
		}

		return true;
	}

	/**
	 * Creates Apple-style reflection under image, optionally adding a border to main image
	 *
	 * @param int    $percent
	 * @param int    $reflection
	 * @param int    $white
	 * @param bool   $border
	 * @param string $borderColor
	 */
	function createReflection( $percent, $reflection, $white, $border = true, $borderColor = '#a4a4a4' ) {
		$width  = $this->currentDimensions['width'];
		$height = $this->currentDimensions['height'];

		$reflectionHeight = intval( $height * ( $reflection / 100 ) );
		$newHeight        = $height + $reflectionHeight;
		$reflectedPart    = $height * ( $percent / 100 );

		$this->workingImage = ImageCreateTrueColor( $width, $newHeight );

		ImageAlphaBlending( $this->workingImage, true );

		$colorToPaint = ImageColorAllocateAlpha( $this->workingImage, 255, 255, 255, 0 );
		ImageFilledRectangle( $this->workingImage, 0, 0, $width, $newHeight, $colorToPaint );

		imagecopyresampled(
			$this->workingImage,
			$this->newImage,
			0,
			0,
			0,
			$reflectedPart,
			$width,
			$reflectionHeight,
			$width,
			( $height - $reflectedPart )
		);
		$this->imageFlipVertical();

		imagecopy( $this->workingImage, $this->newImage, 0, 0, 0, 0, $width, $height );

		imagealphablending( $this->workingImage, true );

		for ($i=0;$i<$reflectionHeight;$i++) {
			$colorToPaint = imagecolorallocatealpha( $this->workingImage, 255, 255, 255, ( $i/$reflectionHeight*-1+1 )*$white );
			imagefilledrectangle( $this->workingImage, 0, $height+$i, $width, $height+$i, $colorToPaint );
		}

		if ($border == true) {
			$rgb          = $this->hex2rgb( $borderColor, false );
			$colorToPaint = imagecolorallocate( $this->workingImage, $rgb[0], $rgb[1], $rgb[2] );
			imageline( $this->workingImage, 0, 0, $width, 0, $colorToPaint ); // top line
			imageline( $this->workingImage, 0, $height, $width, $height, $colorToPaint ); // bottom line
			imageline( $this->workingImage, 0, 0, 0, $height, $colorToPaint ); // left line
			imageline( $this->workingImage, $width-1, 0, $width-1, $height, $colorToPaint ); // right line
		}

		$this->oldImage                    = $this->workingImage;
		$this->newImage                    = $this->workingImage;
		$this->currentDimensions['width']  = $width;
		$this->currentDimensions['height'] = $newHeight;
	}

	/**
	 * Flip an image.
	 *
	 * @param bool $horz flip the image in horizontal mode
	 * @param bool $vert flip the image in vertical mode
	 */
	function flipImage( $horz = false, $vert = false ) {

		$sx = $vert ? ( $this->currentDimensions['width'] - 1 ) : 0;
		$sy = $horz ? ( $this->currentDimensions['height'] - 1 ) : 0;
		$sw = $vert ? -$this->currentDimensions['width'] : $this->currentDimensions['width'];
		$sh = $horz ? -$this->currentDimensions['height'] : $this->currentDimensions['height'];

		$this->workingImage = imagecreatetruecolor( $this->currentDimensions['width'], $this->currentDimensions['height'] );

		$this->imagecopyresampled( $this->workingImage, $this->oldImage, 0, 0, $sx, $sy, $this->currentDimensions['width'], $this->currentDimensions['height'], $sw, $sh );
		$this->oldImage = $this->workingImage;
		$this->newImage = $this->workingImage;

		return true;
	}

	/**
	 * Rotate an image clockwise or counter clockwise
	 *
	 * @param string $dir Either CW or CCW
	 */
	function rotateImage( $dir = 'CW' ) {
		$angle = ( $dir == 'CW' ) ? 90 : -90;

		if (function_exists( 'imagerotate' )) {
			$this->workingImage                = imagerotate( $this->oldImage, 360 - $angle, 0 ); // imagerotate() rotates CCW
			$this->currentDimensions['width']  = imagesx( $this->workingImage );
			$this->currentDimensions['height'] = imagesy( $this->workingImage );
			$this->oldImage                    = $this->workingImage;
			$this->newImage                    = $this->workingImage;
			return true;
		}

		$this->workingImage = imagecreatetruecolor( $this->currentDimensions['height'], $this->currentDimensions['width'] );

		imagealphablending( $this->workingImage, false );
		imagesavealpha( $this->workingImage, true );

		switch ($angle) {

			case 90:
				for ( $x = 0; $x < $this->currentDimensions['width']; $x++ ) {
					for ( $y = 0; $y < $this->currentDimensions['height']; $y++ ) {
						if ( !imagecopy( $this->workingImage, $this->oldImage, $this->currentDimensions['height'] - $y - 1, $x, $x, $y, 1, 1 ) ) {
							return false;
						}
					}
				}
				break;

			case -90:
				for ( $x = 0; $x < $this->currentDimensions['width']; $x++ ) {
					for ( $y = 0; $y < $this->currentDimensions['height']; $y++ ) {
						if ( !imagecopy( $this->workingImage, $this->oldImage, $y, $this->currentDimensions['width'] - $x - 1, $x, $y, 1, 1 ) ) {
							return false;
						}
					}
				}
				break;

			default:
				return false;
		}

		$this->currentDimensions['width']  = imagesx( $this->workingImage );
		$this->currentDimensions['height'] = imagesy( $this->workingImage );
		$this->oldImage                    = $this->workingImage;
		$this->newImage                    = $this->workingImage;

		return true;
	}

	/**
	 * Inverts working image, used by reflection function
	 *
	 * @access  private
	 */
	function imageFlipVertical() {
		$x_i = imagesx( $this->workingImage );
		$y_i = imagesy( $this->workingImage );

		for ($x = 0; $x < $x_i; $x++) {
			for ($y = 0; $y < $y_i; $y++) {
				imagecopy( $this->workingImage, $this->workingImage, $x, $y_i - $y - 1, $x, $y, 1, 1 );
			}
		}
	}

	/**
	 * Converts hexidecimal color value to rgb values and returns as array/string
	 *
	 * @param string $hex
	 * @param bool   $asString
	 * @return array|string
	 */
	function hex2rgb( $hex, $asString = false ) {
		// strip off any leading #
		if (0 === strpos( $hex, '#' )) {
			$hex = substr( $hex, 1 );
		} elseif (0 === strpos( $hex, '&H' )) {
			$hex = substr( $hex, 2 );
		}

		// break into hex 3-tuple
		$cutpoint = ceil( strlen( $hex ) / 2 )-1;
		$rgb      = explode( ':', wordwrap( $hex, $cutpoint, ':', $cutpoint ), 3 );

		// convert each tuple to decimal
		$rgb[0] = ( isset( $rgb[0] ) ? hexdec( $rgb[0] ) : 0 );
		$rgb[1] = ( isset( $rgb[1] ) ? hexdec( $rgb[1] ) : 0 );
		$rgb[2] = ( isset( $rgb[2] ) ? hexdec( $rgb[2] ) : 0 );

		return ( $asString ? "{$rgb[0]} {$rgb[1]} {$rgb[2]}" : $rgb );
	}

	/**
	 * Based on the Watermark function by Marek Malcherek
	 * http://www.malcherek.de
	 *
	 * @param string $color
	 * @param string $wmFont
	 * @param int    $wmSize
	 * @param int    $wmOpaque
	 */
	function watermarkCreateText( $color, $wmFont, $wmSize = 10, $wmOpaque = 90 ) {
		if ( empty( $this->watermarkText ) ) {
			return;
		}

		if (!$color) {
			$color = '000000';
		}

		// set font path
		$wmFontPath = NGGALLERY_ABSPATH . "fonts/" . $wmFont;
		if ( !is_readable( $wmFontPath )) {
			return;
		}

		// This function requires both the GD library and the FreeType library.
		if ( !function_exists( 'ImageTTFBBox' ) ) {
			return;
		}

		$TextSize   = @ImageTTFBBox( $wmSize, 0, $wmFontPath, $this->watermarkText ) or die;
		$TextWidth  = abs( $TextSize[2] ) + abs( $TextSize[0] );
		$TextHeight = abs( $TextSize[7] ) + abs( $TextSize[1] );
		// Create Image for Text
		$this->workingImage = ImageCreateTrueColor( $TextWidth, $TextHeight );
		ImageSaveAlpha( $this->workingImage, true );
		ImageAlphaBlending( $this->workingImage, false );
		$bgText = imagecolorallocatealpha( $this->workingImage, 255, 255, 255, 127 );
		imagefill( $this->workingImage, 0, 0, $bgText );
		$wmTransp  = 127 -( $wmOpaque * 1.27 );
		$rgb       = $this->hex2rgb( $color, false );
		$TextColor = imagecolorallocatealpha( $this->workingImage, $rgb[0], $rgb[1], $rgb[2], $wmTransp );

		// Create Text on image
		imagettftext( $this->workingImage, $wmSize, 0, 0, abs( $TextSize[5] ), $TextColor, $wmFontPath, $this->watermarkText );
		$this->watermarkImgPath = $this->workingImage;

		return;
	}

	/**
	 * Modfied Watermark function by Steve Peart
	 * http://parasitehosting.com/
	 *
	 * @param string $relPOS
	 * @param int    $xPOS
	 * @param int    $yPOS
	 */
	function watermarkImage( $relPOS = 'botRight', $xPOS = 0, $yPOS = 0 ) {

		// if it's a resource ID take it as watermark text image
		if (is_resource( $this->watermarkImgPath ) || $this->watermarkImgPath instanceof GdImage) {
			$this->workingImage = $this->watermarkImgPath;
		} else {
			// Would you really want to use anything other than a png?
			$this->workingImage = @imagecreatefrompng( $this->watermarkImgPath );
			// if it's not a valid file die...
			if (empty( $this->workingImage ) or ( !$this->workingImage )) {
				return;
			}
		}

		imagealphablending( $this->workingImage, false );
		imagesavealpha( $this->workingImage, true );
		$sourcefile_width     =imageSX( $this->oldImage );
		$sourcefile_height    =imageSY( $this->oldImage );
		$watermarkfile_width  =imageSX( $this->workingImage );
		$watermarkfile_height =imageSY( $this->workingImage );
		switch (substr( $relPOS, 0, 3 )) {
			case 'top':
				$dest_y = 0 + $yPOS;
				break;
			case 'mid':
				$dest_y = ( $sourcefile_height / 2 ) - ( $watermarkfile_height / 2 );
				break;
			case 'bot':
				$dest_y = $sourcefile_height - $watermarkfile_height - $yPOS;
				break;
			default:
				$dest_y = 0;
				break;
		}
		switch (substr( $relPOS, 3 )) {
			case 'Left':
				$dest_x = 0 + $xPOS;
				break;
			case 'Center':
				$dest_x = ( $sourcefile_width / 2 ) - ( $watermarkfile_width / 2 );
				break;
			case 'Right':
				$dest_x = $sourcefile_width - $watermarkfile_width - $xPOS;
				break;
			default:
				$dest_x = 0;
				break;
		}

		// debug
		// $this->errmsg = 'X '.$dest_x.' Y '.$dest_y;
		// $this->showErrorImage();

		// if a gif, we have to upsample it to a truecolor image
		if ($this->format == 'GIF') {
			$tempimage = imagecreatetruecolor( $sourcefile_width, $sourcefile_height );
			imagecopy( $tempimage, $this->oldImage, 0, 0, 0, 0, $sourcefile_width, $sourcefile_height );
			$this->newImage = $tempimage;
		}

		imagecopy( $this->newImage, $this->workingImage, $dest_x, $dest_y, 0, 0, $watermarkfile_width, $watermarkfile_height );
	}

	/**
	 * Modfied imagecopyresampled function to save transparent images
	 * See : http://www.akemapa.com/2008/07/10/php-gd-resize-transparent-image-png-gif/
	 *
	 * @since 1.9.0
	 *
	 * @param resource $dst_image
	 * @param resource $src_image
	 * @param int      $dst_x
	 * @param int      $dst_y
	 * @param int      $src_x
	 * @param int      $src_y
	 * @param int      $dst_w
	 * @param int      $dst_h
	 * @param int      $src_w
	 * @param int      $src_h
	 * @return bool
	 */
	function imagecopyresampled( &$dst_image, $src_image, $dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h ) {

		// Check if this image is PNG or GIF, then set if Transparent
		if ( $this->format == 'GIF' || $this->format == 'PNG') {
			imagealphablending( $dst_image, false );
			imagesavealpha( $dst_image, true );
			$transparent = imagecolorallocatealpha( $dst_image, 255, 255, 255, 127 );
			imagefilledrectangle( $dst_image, 0, 0, $dst_w, $dst_h, $transparent );
		}

		imagecopyresampled( $dst_image, $src_image, $dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h );
		return true;
	}
}
