<?php /* $Id$ */
# ImageThumb - a simple on-the-fly image thumbnailer in PHP.
# Copyright (C) 2003, 2004, 2005 Marco Olivo - modified 2005 by Chris Rossi
#
# 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.

/***********************************************************************/
/* ImageThumb, v.1.1                                                   */
/* - creates a thumbnail of up to the given size of the given image,   */
/*   keeping the original aspect ratio.                                */
/* Copyright (C) by Marco Olivo, 2003-2005                             */
/* Modified by Chris Rossi, 2005                                       */
/* This sofware can be found at:                                       */
/* http://www.olivo.net/software/imagethumb/                           */
/*                                                                     */
/* PARAMETERS                                                          */
/* ----------                                                          */
/* s - the path to the image to be resized (can also be an URL)        */
/* w - the max width desired (optional, default: 320)                  */
/* h - the max height desired (optional, default: 200)                 */
/*                                                                     */
/* GD-library compiled and loaded in PHP is REQUIRED.                  */
/*                                                                     */
/* This software is distributed under GPL license 2 or following.      */
/*                                                                     */
/***********************************************************************/

/* some script configuration */
$GENERATE_CACHE = true; /* if true, generates caches of the thumbnailed images */
$CACHE_PATH = '/tmp/imagethumbs/';      /* the full path where thumbnails should be saved (if $GENERATE_CACHE is enabled) */
$BROKEN_IMAGE_PATH = '/path_to/broken.png';     /* the full path to the image to be shown when a non-valid image is required or found */
$BASE_HREF = '';        /* the path string to prepend to every image requested (except external resources, if they are allowed) */
$ALLOW_EXTERNAL_IMAGES = true;  /* allow requests of http:// or ftp:// resources? */

/* some settings */
ignore_user_abort();
set_time_limit( 0 );
error_reporting( FATAL | ERROR | WARNING );

/* security check */
ini_set( 'register_globals', '0' );

/* start buffered output */
ob_start();

function filemtime_remote( $uri ) {
        $uri = parse_url( $uri );
        $uri['port'] = isset( $uri['port'] ) ? $uri['port'] : 80;
        $handle = @fsockopen( $uri['host'], $uri['port'] );
        if( ! $handle ) return 0;

        fputs( $handle, "HEAD $uri[path] HTTP/1.1\r\nHost: $uri[host]\r\n\r\n" );
        $result = 0;
        while( ! feof( $handle ) ) {
                $line = fgets( $handle, 1024 );
                if( ! trim( $line ) ) break;

                $col = strpos( $line, ':' );
                if( $col !== false ) {
                        $header = trim( substr( $line, 0, $col ) );
                        $value = trim( substr( $line, $col + 1 ) );
                        if( strtolower( $header ) == 'last-modified' ) {
                                $result = strtotime( $value );
                                break;
                        }
                }
        }
        fclose( $handle );
        return $result;
}

/* temporary kludge */
//while ( list( $key, $val ) = each( $HTTP_GET_VARS ) ) $_GET[ $key ] = $val;

if ( ! eregi( "^http://", $_GET['s'] ) && ! eregi( "^ftp://", $_GET['s'] ) ) {
        $_GET['s'] = $BASE_HREF . $_GET['s'];
}

/* get source image size */
$src_size = getimagesize( $_GET['s'] );

/* some checks */
if ( ! isset( $_GET['s'] ) ) die( 'Source image not specified' );
if ( isset( $_GET['w'] ) && ereg( "^[0-9]+$", $_GET['w'] ) ) $MAX_WIDTH = $_GET['w'];
else $MAX_WIDTH = $src_size[0];
if ( isset( $_GET['h'] ) && ereg( "^[0-9]+$", $_GET['h'] ) ) $MAX_HEIGHT = $_GET['h'];
else $MAX_HEIGHT = $src_size[1];

/* avoid the .. trick */
if ( ereg( "\.\./", $_GET['s'] ) || ereg( "\.\.\\\\", $_GET['s'] ) ) {
    print 'Hack attempt, your attempt together with your IP-address has been registered in system logs. Have a nice day.';

        /* end buffered output */
        ob_end_flush();

    exit();
}

if ( ! $ALLOW_HTTP_IMAGES && ( eregi( "^http://", $_GET['s'] ) || eregi( "^ftp://", $_GET['s'] ) ) ) {
        $data = readfile( $BROKEN_IMAGE_PATH );
        $dest = imagecreatefromstring( $data );
        header( 'Content-type: image/jpeg' );
        imagejpeg( $dest );

        /* end buffered output */
        ob_end_flush();

    exit();
}

/* for creating md5 thumbnail file that will update when file is changed */
$full_url = str_replace( 'http://', '', $_GET['s'] );
$full_url = filemtime_remote( $_GET['s'] ) . '_' . $MAX_WIDTH . '_' . $MAX_HEIGHT . '_' . $full_url;

$ext = strtolower( substr( $_GET['s'], strrpos( $_GET['s'], '.' ) + 1 ) );

$thumb_file = md5( $full_url ) . '_' . basename( $_GET['s'] );
$png_thumb_file = str_replace( '.' . $ext, '.png', $thumb_file );
$gif_thumb_file = str_replace( '.' . $ext, '.gif', $thumb_file );
$jpg_thumb_file = str_replace( '.' . $ext, '.jpg', $thumb_file );

if ( ( ! file_exists( $CACHE_PATH . $png_thumb_file ) &&
           ! file_exists( $CACHE_PATH . $gif_thumb_file ) &&
           ! file_exists( $CACHE_PATH . $jpg_thumb_file ) ) ) {

        /* resize the image (if needed) */
        if ( $src_size[0] > $MAX_WIDTH && $src_size[1] > $MAX_HEIGHT ) {
                if ( $src_size[0] > $src_size[1] ) {
                        $dest_width = $MAX_WIDTH;
                        $dest_height = ( $src_size[1] * $MAX_WIDTH ) / $src_size[0];
                }
                else {
                        $dest_width = ( $src_size[0] * $MAX_HEIGHT ) / $src_size[1];
                        $dest_height = $MAX_HEIGHT;
                }
        }
        else if ( $src_size[0] > $MAX_WIDTH ) {
                $dest_width = $MAX_WIDTH;
                $dest_height = ( $src_size[1] * $MAX_WIDTH ) / $src_size[0];
        }
        else if ( $src_size[1] > $MAX_HEIGHT ) {
                $dest_width = ( $src_size[0] * $MAX_HEIGHT ) / $src_size[1];
                $dest_height = $MAX_HEIGHT;
        }
        else {
                $dest_width = $src_size[0];
                $dest_height = $src_size[1];
        }

        /* force resizing in both dimensions? */
        if ( isset( $_GET['w'] ) && isset( $_GET['h'] ) ) {
                $dest_width = $MAX_WIDTH;
                $dest_height = $MAX_WIDTH;
        }

        if ( extension_loaded( 'gd' ) ) {

                /* check the source file format */
                if ( $ext == 'jpg' || $ext == 'jpeg' ) $src = imagecreatefromjpeg( $_GET['s'] ) or $failed = true;
                else if ( $ext == 'gif' ) $src = imagecreatefromgif( $_GET['s'] ) or $failed = true;
                else if ( $ext == 'png' ) $src = imagecreatefrompng( $_GET['s'] ) or $failed = true;
                else $failed = true;

                if( $failed != true ) {
                        /* create and output the destination image */
                        $dest = imagecreatetruecolor( $dest_width, $dest_height ) or die( 'Cannot initialize new GD image stream' );
                        imagecopyresampled( $dest, $src, 0, 0, 0, 0, $dest_width, $dest_height, $src_size[0], $src_size[1] );

                        if ( imagetypes() & IMG_PNG ) {
                                header( 'Content-Disposition: inline; filename="' . str_replace( '.' . $ext, '.png', basename( $_GET['s'] ) ) . '"' );
                                header( 'Content-type: image/png' );
                                if ( $GENERATE_CACHE ) imagepng( $dest , $CACHE_PATH . $png_thumb_file );
                                imagepng( $dest );
                        }
                        elseif ( imagetypes() & IMG_JPG ) {
                                header( 'Content-Disposition: inline; filename="' . str_replace( '.' . $ext, '.jpg', basename( $_GET['s'] ) ) . '"' );
                                header( 'Content-type: image/jpeg' );
                                if ( $GENERATE_CACHE ) imagejpeg( $dest , $CACHE_PATH . $jpg_thumb_file );
                                imagejpeg( $dest );
                        }
                        else if ( imagetypes() & IMG_GIF ) {
                                header( 'Content-Disposition: inline; filename="' . str_replace( '.' . $ext, '.gif', basename( $_GET['s'] ) ) . '"' );
                                header( 'Content-type: image/gif' );
                                if ( $GENERATE_CACHE ) imagegif( $dest , $CACHE_PATH . $gif_thumb_file );
                                imagegif( $dest );
                        }
                        else {
                                $data = readfile( $BROKEN_IMAGE_PATH );
                                $dest = imagecreatefromstring( $data );
                                header( 'Content-type: image/jpeg' );
                                imagejpeg( $dest );
                        }
                }
                else {
                        $data = readfile( $BROKEN_IMAGE_PATH );
                        $dest = imagecreatefromstring( $data );
                        header( 'Content-type: image/jpeg' );
                        imagejpeg( $dest );
                }
        }
        else print 'GD-library support is not available';
}
else {
        if ( file_exists( $CACHE_PATH . $png_thumb_file ) ) {
                /* use PNG */
                $dest = imagecreatefrompng( $CACHE_PATH . $png_thumb_file );
                header( 'Content-type: image/jpeg' );
                imagejpeg( $dest );
                touch( $CACHE_PATH . $png_thumb_file );
        }
        else if ( file_exists( $CACHE_PATH . $jpg_thumb_file ) ) {
                /* use JPG */
                $dest = imagecreatefromjpeg( $CACHE_PATH . $jpg_thumb_file );
                header( 'Content-type: image/jpeg' );
                imagejpeg( $dest );
                touch( $CACHE_PATH . $jpg_thumb_file );
        }
        else if ( file_exists( $CACHE_PATH . $gif_thumb_file ) ) {
                /* use GIF */
                $dest = imagecreatefromgif( $CACHE_PATH . $gif_thumb_file );
                header( 'Content-type: image/jpeg' );
                imagejpeg( $dest );
                touch( $CACHE_PATH . $gif_thumb_file );
        }
        else {
                $data = readfile( $BROKEN_IMAGE_PATH );
                $dest = imagecreatefromstring( $data );
                header( 'Content-type: image/jpeg' );
                imagejpeg( $dest );
        }
}

/* end buffered output */
ob_end_flush();

/* destroy the buffer of the image in order to free up used memory */
imagedestroy();
?>

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