<?php
/*
Thumby v 0.1, GPL 2, http://eight6.com/projects/thumby/

Created by Noel Jackson (http://eight6.com) for PhotoStack (http://photostack.org).

A simple class that creates and caches a thumbnail of the specified size for the specified image.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

$cache = $_SERVER['DOCUMENT_ROOT'].'/cache/';

$image_request = $_REQUEST['image'];

new Thumby( $image_request, $cache, ( int ) $_REQUEST['w'], ( int ) ( $_REQUEST['h'] ), isset( $_REQUEST['f'] ) );

class Thumby {

	function not_found() {
		header( 'HTTP/1.0 404 Not Found' );
		echo 'File not found.';
		exit;
	}

	function __construct( $image, $pathto_cache, $max_width = 1200, $max_height = 1200, $force_size = 0 ) {
		if ( $force_size = '' ) $force_size = 0;
		if ( $max_width == 0 ) $max_width = 1200;
		if ( $max_height == 0 ) $max_height = 1200;

		// If you know what you're doing, you can set this to "im" for ImageMagick, make sure to change $convert_path below
		$software = 'gd';
		$gal_path = $_SERVER['DOCUMENT_ROOT'];
		$ext = strtolower( pathinfo( $image, PATHINFO_EXTENSION ) );
		$extensions = explode( ',', 'jpg,jpe,jpeg,png,gif' );
			$image_path = $gal_path.'/'.$image;

		if ( strpos($image, './' ) or !in_array( $ext, $extensions ) or !file_exists( $image_path ) )
				$this->not_found();

			$thumb_path = $pathto_cache.$max_width.'x'.$max_height.( $force_size?'f':'' ).strtr( '-$gallery-$image', ':/?\\', '----' );
			$imageModified = @filemtime( $image_path );
			$thumbModified = @filemtime( $thumb_path );

		switch( $ext ) {
			case 'gif' : header( 'Content-type: image/gif' ); break;
			case 'png' : header( 'Content-type: image/png' ); break;
			default: header( 'Content-type: image/jpeg' ); break;
		}
		//if thumbnail is newer than image then output cached thumbnail and exit
		if ( $imageModified<$thumbModified ) {
			header( 'Last-Modified: '.gmdate( 'D, d M Y H:i:s', $thumbModified).' GMT' );
			readfile($thumb_path);
			exit;
		} else {
			$this->make_thumb($image_path, $thumb_path, $force_size, $max_width, $max_height);
		}
	}

	function make_thumb( $image_path, $thumb_path, $force_size, $max_width = 1200, $max_height = 1200, $software='gd2', $convert_path = null ) {

		$convert_path = '/opt/local/bin/convert';

		$thumbQuality = 95;
		list( $image_width, $image_height, $image_type ) = GetImageSize( $image_path );

		//if aspect ratio is to be constrained set crop size
		if ( $force_size ) {
			$newAspect = $max_width/$max_height;
			$oldAspect = $image_width/$image_height;

			if ( $newAspect > $oldAspect ) {
				$cropWidth = $image_width;
				$cropHeight = round( $oldAspect/$newAspect * $image_height );
			} else {
				$cropWidth = round( $newAspect/$oldAspect * $image_width );
				$cropHeight = $image_height;
			}
		//else crop size is image size
		} else {
			$cropWidth = $image_width;
			$cropHeight = $image_height;
		}

		//set cropping offset
		$cropX = floor( ( $image_width-$cropWidth )/2 );
		$cropY = floor( ( $image_height-$cropHeight )/2 );

		//compute width and height of thumbnail to create
		if ( $cropWidth >= $max_width && ( $cropHeight < $max_height || ( $cropHeight > $max_height && round( $cropWidth/$cropHeight * $max_height ) > $max_width ) ) ) {
			$thumbWidth = $max_width;
			$thumbHeight = round( $cropHeight/$cropWidth * $max_width );
		} elseif ( $cropHeight >= $max_height ) {
			$thumbWidth = round( $cropWidth/$cropHeight * $max_height );
		    $thumbHeight = $max_height;
		} else {
			//image is smaller than required dimensions so output it and exit
			readfile( $image_path );
			exit;
		}

		switch( $software ) {
			case 'im' : //use ImageMagick
			// hack for square thumbs;
			if ( ( $thumbWidth == $thumbHeight ) or $force_size ) {
				$thumbsize = $thumbWidth;
				if ( $image_height > $image_width ) {
					$cropY = -($thumbsize / 2);
					$cropX = 0;
					$thumbcommand = '{$thumbsize}x';
				} else {
					$cropY = -($thumbsize / 2);
					$cropX = 0;
					$thumbcommand = 'x{$thumbsize}';
				}
			} else {
				$thumbcommand = $thumbWidth.'x'.$thumbHeight;
			}
			$cmd  = '"'.$convert_path.'"';
			if ( $force_size ) $cmd .= ' -gravity center -crop {$thumbWidth}x{$thumbHeight}!+0+0';
			$cmd .= ' -resize {$thumbcommand}';
			if ( $image_type == 2 ) $cmd .= ' -quality $thumbQuality';
			$cmd .= ' -interlace Plane';
			$cmd .= ' +profile "*"';
			$cmd .= ' '.escapeshellarg( $image_path ).' '.escapeshellarg( $thumb_path );
			exec( $cmd );
			readfile( $thumb_path );
			exit;
			break;

			case 'gd2' :
			default : //use GD by default
			//read in image as appropriate type
			switch( $image_type ) {
				case 1 : $image = ImageCreateFromGIF( $image_path ); break;
				case 3 : $image = ImageCreateFromPNG( $image_path ); break;
				case 2 :
				default: $image = ImageCreateFromJPEG( $image_path ); break;
			}

			//create blank truecolor image
			$thumb = ImageCreateTrueColor( $thumbWidth,$thumbHeight );

			//resize image with resampling
			ImageCopyResampled( $thumb, $image, 0, 0, $cropX, $cropY, $thumbWidth, $thumbHeight, $cropWidth, $cropHeight );

			//set image interlacing
			ImageInterlace( $thumb, $this->config->progressive_thumbs );

			//output image of appropriate type
			switch( $image_type ) {
				case 1 :
				//GIF images are output as PNG
				case 3 :
				ImagePNG( $thumb,$thumb_path );
				break;
				case 2 :
				default:
				ImageJPEG( $thumb,$thumb_path,$thumbQuality );
				break;
			}
			ImageDestroy( $image );
			ImageDestroy( $thumb );
			readfile( $thumb_path );
		}
	}
}
?>