- plugins can have full control over the path/url of the element/image/

thumbnail/high (it is possible now to have secure images, on the fly 
watermarking, mod download and media integrator plugins working together in 
any combination and without touching PWG core)

git-svn-id: http://piwigo.org/svn/trunk@1612 68402e56-0260-453c-a942-63ccdbb3a9ee

3 files changed, 349 insertions, 104 deletions

diff --git a/action.php b/action.php
index 7e853ed44..6b21b0fa1 100644
--- a/action.php
+++ b/action.php
@@ -31,69 +31,127 @@ include_once(PHPWG_ROOT_PATH.'include/common.inc.php');
 // Check Access and exit when user status is not ok
 check_status(ACCESS_GUEST);
 
-function force_download ($filename)
+function guess_mime_type($ext)
 {
-//TODO : messages in "lang"
-  if (!url_is_remote($filename))
+  switch ( strtolower($ext) )
   {
-    $filename = realpath($filename);
-    if (!file_exists($filename))
-    {
-      die("NO FILE HERE");
-    }
-    $file_size = @filesize($filename);
-  }
-  else
-  {
-    $file_size = 0;
+    case "jpe": case "jpeg":
+    case "jpg": $ctype="image/jpeg"; break;
+    case "png": $ctype="image/png"; break;
+    case "gif": $ctype="image/gif"; break;
+    case "tiff":
+    case "tif": $ctype="image/tiff"; break;
+    case "txt": $ctype="text/plain"; break;
+    case "html":
+    case "htm": $ctype="text/html"; break;
+    case "xml": $ctype="text/xml"; break;
+    case "pdf": $ctype="application/pdf"; break;
+    case "zip": $ctype="application/zip"; break;
+    case "ogg": $ctype="application/ogg"; break;
+    default: $ctype="application/octet-stream";
   }
+  return $ctype;
+}
 
-  $file_extension = strtolower(substr(strrchr($filename,"."),1));
-
-  switch ($file_extension) {
-      case "jpe": case "jpeg":
-      case "jpg": $ctype="image/jpg"; break;
-      case "png": $ctype="image/png"; break;
-      case "gif": $ctype="image/gif"; break;
-      case "pdf": $ctype="application/pdf"; break;
-      case "zip": $ctype="application/zip"; break;
-      case "php": 
-        // never allow download of php scripts to protect our conf files
-        die('Hacking attempt!'); break;
-      default: $ctype="application/octet-stream";
-  }
+function do_error( $code, $str )
+{
+  header("HTTP/1.1 $code ");
+  header("Status: $code ");
+  echo $str ;
+  exit();
+}
+
+
+if ( !isset($_GET['id']) or !is_numeric($_GET['id'])
+    or !isset($_GET['part'])
+    or !in_array($_GET['part'], array('t','e','i','h') ) )
+{
+  do_error(400, 'Invalid request - id/part');
+}
+
+$id = $_GET['id'];
+$query = '
+SELECT * FROM '. IMAGES_TABLE.'
+  WHERE id='.$id.'
+;';
+
+$result = pwg_query($query);
+$element_info = mysql_fetch_assoc($result);
+if ( empty($element_info) )
+{
+  do_error(404, 'Requested id not found');
+}
+
+// TODO - check permissions
+
+include_once(PHPWG_ROOT_PATH.'include/functions_picture.inc.php');
+$file='';
+switch ($_GET['part'])
+{
+  case 't':
+    $file = get_thumbnail_path($element_info);
+    break;
+  case 'e':
+    $file = get_element_path($element_info);
+    break;
+  case 'i':
+    $file = get_image_path($element_info);
+    break;
+  case 'h':
+    $file = get_high_path($element_info);
+    break;
+}
+
+if ( empty($file) )
+{
+  do_error(404, 'Requested file not found');
+}
+
+$http_headers = array();
 
-  header("Pragma: public");
-  header("Expires: 0");
-  header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
-  header("Cache-Control: private",false);
-  header("Content-Type: $ctype");
-  header("Content-Disposition: attachment; filename=\""
-         .basename($filename)."\";");
-  header("Content-Transfer-Encoding: binary");
-  if (isset($file_size) and ($file_size != 0))
+$ctype = null;
+if (!url_is_remote($file))
+{
+  if ( !@is_readable($file) )
   {
-    header("Content-Length: ".@filesize($filename));
+    do_error(404, "Requested file not found - $file");
   }
-
-  // Looking at the safe_mode configuration for execution time
-  if (ini_get('safe_mode') == 0)
+  $http_headers[] = 'Content-Length: '.@filesize($file);
+  if ( function_exists('mime_content_type') )
   {
-    @set_time_limit(0);
+    $ctype = mime_content_type($file);
   }
+}
+if (!isset($ctype))
+{ // give it a guess
+  $ctype = guess_mime_type( get_extension($file) );
+}
 
-  @readfile("$filename") or die("File not found.");
+$http_headers[] = 'Content-Type: '.$ctype;
+
+if (!isset($_GET['view']))
+{
+  $http_headers[] = 'Content-Disposition: attachment; filename="'
+            .basename($file).'";';
+  $http_headers[] = 'Content-Transfer-Encoding: binary';
 }
+$http_headers[] = 'Pragma: public';
+$http_headers[] = 'Expires: 0';
+$http_headers[] = 'Cache-Control: must-revalidate, post-check=0, pre-check=0';
 
-//--------------------------------------------------------- download big picture
-if ( isset( $_GET['dwn'] ) )
+
+foreach ($http_headers as $header)
 {
-//TODO : verify the path begins with something in galleries_url and that user has access rights to the picture
-// in order to avoid hacking atempts by forged url
-  if (preg_match('/\.\./',$_GET['dwn'])) {
-    die('Hacking attempt!');
-  }
-  force_download($_GET['dwn']);
+  header( $header );
 }
+header("Cache-Control: private",false); //???
+
+// Looking at the safe_mode configuration for execution time
+if (ini_get('safe_mode') == 0)
+{
+  @set_time_limit(0);
+}
+
+@readfile($file);
 
-?>
+?>
\ No newline at end of file
diff --git a/include/functions_picture.inc.php b/include/functions_picture.inc.php
new file mode 100644
index 000000000..572ef8207
--- /dev/null
+++ b/include/functions_picture.inc.php
@@ -0,0 +1,222 @@
+<?php
+// +-----------------------------------------------------------------------+
+// | PhpWebGallery - a PHP based picture gallery                           |
+// | Copyright (C) 2003-2006 PhpWebGallery Team - http://phpwebgallery.net |
+// +-----------------------------------------------------------------------+
+// | branch        : BSF (Best So Far)
+// | file          : $RCSfile$
+// | last update   : $Date$
+// | last modifier : $Author$
+// | revision      : $Revision$
+// +-----------------------------------------------------------------------+
+// | 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                                          |
+// |                                                                       |
+// | 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.                                                                  |
+// +-----------------------------------------------------------------------+
+
+/**
+ * @param element_info array containing element information from db;
+ * at least 'id', 'path' should be present
+ */
+function get_element_path($element_info)
+{
+  $path = get_element_location($element_info);
+  if ( !url_is_remote($path) )
+  {
+    $path = PHPWG_ROOT_PATH.$path;
+  }
+  return $path;
+}
+
+/*
+ * @param element_info array containing element information from db;
+ * at least 'id', 'path' should be present
+ */
+function get_element_url($element_info)
+{
+  $url = get_element_location($element_info);
+  if ( !url_is_remote($url) )
+  {
+    $url = get_root_url().$url;
+  }
+  // plugins want another url ?
+  return trigger_event('get_element_url', $url, $element_info);
+}
+
+/**
+ * Returns the relative path of the element with regards to to the root
+ * of PWG (not the current page). This function is not intended to be
+ * called directly from code.
+ * @param element_info array containing element information from db;
+ * at least 'id', 'path' should be present
+ */
+function get_element_location($element_info)
+{
+  // maybe a cached watermark ?
+  return trigger_event('get_element_location',
+    $element_info['path'], $element_info);
+}
+
+
+/**
+ * Returns the PATH to the image to be displayed in the picture page. If the
+ * element is not a picture, then the representative image or the default
+ * mime image. The path can be used in the php script, but not sent to the
+ * browser.
+ * @param element_info array containing element information from db;
+ * at least 'id', 'path', 'representative_ext' should be present
+ */
+function get_image_path($element_info)
+{
+  global $conf;
+  $ext = get_extension($element_info['path']);
+  if (in_array($ext, $conf['picture_ext']))
+  {
+    if (isset($element_info['element_path']) )
+    {
+      return $element_info['element_path'];
+    }
+    return get_element_path($element_info);
+  }
+
+  $path = get_image_location($element_info);
+  if ( !url_is_remote($path) )
+  {
+    $path = PHPWG_ROOT_PATH.$path;
+  }
+  return $path;
+}
+
+/**
+ * Returns the URL of the image to be displayed in the picture page. If the
+ * element is not a picture, then the representative image or the default
+ * mime image. The URL can't be used in the php script, but can be sent to the
+ * browser.
+ * @param element_info array containing element information from db;
+ * at least 'id', 'path', 'representative_ext' should be present
+ */
+function get_image_url($element_info)
+{
+  global $conf;
+  $ext = get_extension($element_info['path']);
+  if (in_array($ext, $conf['picture_ext']))
+  {
+    if (isset($element_info['element_url']) )
+    {
+      return $element_info['element_url'];
+    }
+    return get_element_url($element_info);
+  }
+
+  $url = get_image_location($element_info);
+  if ( !url_is_remote($url) )
+  {
+    $url = get_root_url().$url;
+  }
+  return $url;
+}
+
+/**
+ * Returns the relative path of the image (element/representative/mimetype)
+ * with regards to the root of PWG (not the current page). This function
+ * is not intended to be called directly from code.
+ * @param element_info array containing element information from db;
+ * at least 'id', 'path', 'representative_ext' should be present
+ */
+function get_image_location($element_info)
+{
+    if (isset($element_info['representative_ext'])
+          and $element_info['representative_ext'] != '')
+    {
+      $pi = pathinfo($element_info['path']);
+      $file_wo_ext = get_filename_wo_extension($pi['basename']);
+      $path =
+        $pi['dirname'].'/pwg_representative/'
+        .$file_wo_ext.'.'.$element_info['representative_ext'];
+    }
+    else
+    {
+      $ext = get_extension($element_info['path']);
+      $path = get_themeconf('mime_icon_dir');
+      $path.= strtolower($ext).'.png';
+    }
+
+  // plugins want another location ?
+  return trigger_event( 'get_image_location', $path, $element_info);
+}
+
+
+/*
+ * @param element_info array containing element information from db;
+ * at least 'id', 'path', 'has_high' should be present
+ */
+function get_high_path($element_info)
+{
+  $path = get_high_location($element_info);
+  if (!empty($path) and !url_is_remote($path) )
+  {
+    $path = PHPWG_ROOT_PATH.$path;
+  }
+  return $path;
+}
+
+/**
+ * @param element_info array containing element information from db;
+ * at least 'id', 'path', 'has_high' should be present
+ */
+function get_high_url($element_info)
+{
+  $url = get_high_location($element_info);
+  if (!empty($url) and !url_is_remote($url) )
+  {
+    $url = get_root_url().$url;
+  }
+  // plugins want another url ?
+  return trigger_event('get_high_url', $url, $element_info);
+}
+
+/**
+ * @param element_info array containing element information from db;
+ * at least 'id', 'path', 'has_high' should be present
+ */
+function get_high_location($element_info)
+{
+  $location = '';
+  if ($element_info['has_high'] == 'true')
+  {
+    $pi = pathinfo($element_info['path']);
+    $location=$pi['dirname'].'/pwg_high/'.$pi['basename'];
+  }
+  return trigger_event( 'get_high_location', $location, $element_info);
+}
+
+
+/**
+ * @param what_part string one of 't' (thumbnail), 'e' (element), 'i' (image),
+ *   'h' (high resolution image)
+ * @param element_info array containing element information from db;
+ * at least 'id', 'path' should be present
+ */
+function get_download_url($what_part, $element_info)
+{
+  $url = get_root_url().'action.php';
+  $url = add_url_params($url,
+      array(
+        'id' => $element_info['id'],
+        'part' => $what_part,
+      )
+    );
+  return trigger_event( 'get_download_url', $url, $element_info);
+}
+
+?>
\ No newline at end of file
diff --git a/picture.php b/picture.php
index dd7ffa3ae..be5971a6a 100644
--- a/picture.php
+++ b/picture.php
@@ -28,6 +28,7 @@
 define('PHPWG_ROOT_PATH','./');
 include_once(PHPWG_ROOT_PATH.'include/common.inc.php');
 include(PHPWG_ROOT_PATH.'include/section_init.inc.php');
+include_once(PHPWG_ROOT_PATH.'include/functions_picture.inc.php');
 
 // Check Access and exit when user status is not ok
 check_status(ACCESS_GUEST);
@@ -310,67 +311,34 @@ while ($row = mysql_fetch_assoc($result))
     $picture[$i]['is_picture'] = true;
   }
 
-  $cat_directory = dirname($row['path']);
-  $file_wo_ext = get_filename_wo_extension($row['file']);
-
   // ------ build element_path and element_url
-  $picture[$i]['element_url'] = $row['path'];
-  if ( ! url_is_remote($row['path']) )
+  $picture[$i]['element_path'] = get_element_path($picture[$i]);
+  $picture[$i]['element_url'] = get_element_url($picture[$i]);
+
+  // ------ build image_path and image_url
+  if ($i=='current' or $i=='next')
   {
-    $picture[$i]['element_url'] = get_root_url().$row['path'];
+    $picture[$i]['image_path'] = get_image_path( $picture[$i] );
+    $picture[$i]['image_url'] = get_image_url( $picture[$i] );
   }
 
-  // ------ build image_path and image_url
-  if ($picture[$i]['is_picture'])
+  if ($i=='current')
   {
-    $picture[$i]['image_path'] = $row['path'];
-    // if we are working on the "current" element, we search if there is a
-    // high quality picture
-    if ($i == 'current')
+    if ( $picture[$i]['is_picture'] )
     {
-      if (($row['has_high'] == 'true') and ($user['enabled_high'] == 'true'))
+      if ( $user['enabled_high']=='true' )
       {
-        $url_high=$cat_directory.'/pwg_high/'.$row['file'];
-         $picture[$i]['high_url'] = $picture[$i]['high_path'] = $url_high;
-        if ( ! url_is_remote($picture[$i]['high_path']) )
+        $hi_url=get_high_url($picture[$i]);
+        if ( !empty($hi_url) )
         {
-          $picture[$i]['high_url'] = get_root_url().$picture[$i]['high_path'];
+          $picture[$i]['high_url'] = $hi_url;
+          $picture[$i]['download_url'] = get_download_url('h',$picture[$i]);
         }
       }
     }
-  }
-  else
-  {// not a picture
-    if (isset($row['representative_ext']) and $row['representative_ext']!='')
-    {
-      $picture[$i]['image_path'] =
-        $cat_directory.'/pwg_representative/'
-        .$file_wo_ext.'.'.$row['representative_ext'];
-    }
     else
-    {
-      $picture[$i]['image_path'] =
-        get_themeconf('mime_icon_dir')
-        .strtolower(get_extension($row['file'])).'.png';
-    }
-  }
-
-  $picture[$i]['image_url'] = $picture[$i]['image_path'];
-  if ( ! url_is_remote($picture[$i]['image_path']) )
-  {
-    $picture[$i]['image_url'] = get_root_url().$picture[$i]['image_path'];
-  }
-
-  if (!$picture[$i]['is_picture'])
-  {// if picture is not a file, we need the download link
-    $picture[$i]['download_url'] = $picture[$i]['element_url'];
-  }
-  else
-  {// if picture is a file with high, we put the download link
-    if ( isset($picture[$i]['high_path']) )
-    {
-      $picture[$i]['download_url'] = get_root_url().'action.php?dwn='
-        .$picture[$i]['high_path'];
+    { // not a pic - need download link
+      $picture[$i]['download_url'] = get_download_url('e',$picture[$i]);
     }
   }
 
@@ -382,6 +350,7 @@ while ($row = mysql_fetch_assoc($result))
   }
   else
   {
+    $file_wo_ext = get_filename_wo_extension($row['file']);
     $picture[$i]['name'] = str_replace('_', ' ', $file_wo_ext);
   }
 
@@ -427,10 +396,6 @@ if (!empty($picture['current']['width']))
     );
 }
 
-// now give an opportunity to the filters to alter element_url,
-// image_url, high_url and download_url
-$picture = trigger_event('picture_navigation', $picture);
-
 $url_admin =
   get_root_url().'admin.php?page=picture_modify'
   .'&amp;cat_id='.(isset($page['category']) ? $page['category'] : '')