This patch helps provide raw photo support with some small changes to the framework. Items can now change their extension and MIME type.

Squashed commit of the following:

commit 4c2b2ebd3f2052898fbfb175650ed4cf49c8006e
Author: Chad Parry <github@chad.parry.org>
Date:   Wed Apr 27 20:52:35 2011 -0600

    Remove a newline at the end of the file that I accidentally introduced.

commit 6d564f185e5279d6cca9a7385066514ff18a2455
Merge: 7ff485f 4060640
Author: Chad Parry <github@chad.parry.org>
Date:   Wed Apr 27 20:35:58 2011 -0600

    Merge branch 'master' of https://github.com/gallery/gallery3 into rawphoto

commit 7ff485fa48c392bbbb0370f67cb1bd6fcc00c2a4
Author: Chad Parry <github@chad.parry.org>
Date:   Wed Apr 27 20:29:06 2011 -0600

    Move the extensions helpers out of the Kohana system directory and into their own Gallery Extensions class.

commit 26585fed03236f0f70a75959e1d3002025f4e15e
Merge: 809567f c8f90e8
Author: Chad Parry <github@chad.parry.org>
Date:   Sun Apr 24 08:28:39 2011 -0600

    Merge branch 'master' of https://github.com/gallery/gallery3 into rawphoto

commit 809567f12850f59bdeb47a2963f6968b99b5a201
Author: Chad Parry <github@chad.parry.org>
Date:   Sun Apr 24 08:10:04 2011 -0600

    Expose the data file field.

commit fcb06bf175bb9eeff36d9c294e97ace9374ef0f3
Author: Chad Parry <github@chad.parry.org>
Date:   Sun Apr 24 00:45:12 2011 -0600

    Don't assign to the item->name field if the name is unchanged, because the save method will crash.

commit c6ef706d70c7e48bea1145eec1b13fb5683e023f
Author: Chad Parry <github@chad.parry.org>
Date:   Sat Apr 23 22:55:59 2011 -0600

    Preserve old data files long enough for them to be available to event handlers.

commit 0d6a3a3cfc4f38f450db9e18da47a5e2ad826af8
Author: Chad Parry <github@chad.parry.org>
Date:   Sat Apr 23 21:19:47 2011 -0600

    Create a tempnam substitute that safely creates files with a given extension.

commit e149cf7238a1f8eaddfc68580f2d636dd8255795
Author: Chad Parry <github@chad.parry.org>
Date:   Sat Apr 23 16:39:25 2011 -0600

    Support data files that change their extension and MIME type.

commit 6702104f571413e4d57db3515b2070c48d3e9b55
Author: Chad Parry <github@chad.parry.org>
Date:   Sat Apr 23 16:35:00 2011 -0600

    Resolve an infinite recursion that happens when the path caches are updated during saving.

commit 944cb72eea946f4c45a04b7e4c7c33929fa8b9f3
Merge: 567522b 5af74d4
Author: Chad Parry <github@chad.parry.org>
Date:   Fri Apr 22 14:10:42 2011 -0600

    Merge remote branch 'origin/master' into rawphoto

commit 567522bfa08c370bb5baf8454afc5b04bc9e49b4
Author: Chad Parry <github@chad.parry.org>
Date:   Thu Apr 21 20:12:32 2011 -0600

    Add an event for when a new graphics toolkit is chosen.

commit 31ba081b793141ca36866a6dd349cd2eac5af68e
Author: Chad Parry <github@chad.parry.org>
Date:   Thu Apr 21 02:06:53 2011 -0600

    Add an event that will collect all valid filename extensions.

10 files changed, 194 insertions, 32 deletions

diff --git a/modules/gallery/controllers/admin_graphics.php b/modules/gallery/controllers/admin_graphics.php
index a2d19d4a..a8a7cdc0 100644
--- a/modules/gallery/controllers/admin_graphics.php
+++ b/modules/gallery/controllers/admin_graphics.php
@@ -40,6 +40,8 @@ class Admin_Graphics_Controller extends Admin_Controller {
       $msg = t("Changed graphics toolkit to: %toolkit", array("toolkit" => $tk->$toolkit_id->name));
       message::success($msg);
       log::success("graphics", $msg);
+
+      module::event("graphics_toolkit_change", $toolkit_id);
     }
 
     url::redirect("admin/graphics");
diff --git a/modules/gallery/controllers/quick.php b/modules/gallery/controllers/quick.php
index da4768fd..ce52cb8d 100644
--- a/modules/gallery/controllers/quick.php
+++ b/modules/gallery/controllers/quick.php
@@ -36,8 +36,8 @@ class Quick_Controller extends Controller {
     }
 
     if ($degrees) {
-      $tmpfile = tempnam(TMPPATH, "rotate") . "." .
-        pathinfo($item->file_path(), PATHINFO_EXTENSION);
+      $tmpfile = system::tempnam(TMPPATH, "rotate",
+        "." . pathinfo($item->file_path(), PATHINFO_EXTENSION));
       gallery_graphics::rotate($item->file_path(), $tmpfile, array("degrees" => $degrees), $item);
       $item->set_data_file($tmpfile);
       $item->save();
diff --git a/modules/gallery/controllers/uploader.php b/modules/gallery/controllers/uploader.php
index 6b1455e4..5f3e9ca4 100644
--- a/modules/gallery/controllers/uploader.php
+++ b/modules/gallery/controllers/uploader.php
@@ -51,7 +51,7 @@ class Uploader_Controller extends Controller {
     $file_validation = new Validation($_FILES);
     $file_validation->add_rules(
       "Filedata", "upload::valid",  "upload::required",
-      "upload::type[gif,jpg,jpeg,png,flv,mp4,m4v]");
+      "upload::type[" . implode(",", extensions::get_upload_extensions()) . "]");
 
     if ($form->validate() && $file_validation->validate()) {
       $temp_filename = upload::save("Filedata");
diff --git a/modules/gallery/helpers/extensions.php b/modules/gallery/helpers/extensions.php
new file mode 100644
index 00000000..bccbfc41
--- /dev/null
+++ b/modules/gallery/helpers/extensions.php
@@ -0,0 +1,39 @@
+<?php defined("SYSPATH") or die("No direct script access.");
+/**
+ * Gallery - a web based photo album viewer and editor
+ * Copyright (C) 2011 Chad Parry
+ *
+ * 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., 51 Franklin Street - Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+class extensions_Core {
+  static function get_upload_extensions() {
+    // Create a default list of allowed extensions and then let modules modify it.
+    $extensions_wrapper = new stdClass();
+    $extensions_wrapper->extensions = array("gif", "jpg", "jpeg", "png");
+    if (movie::find_ffmpeg()) {
+      array_push($extensions_wrapper->extensions, "flv", "mp4", "m4v");
+    }
+    module::event("upload_extensions", $extensions_wrapper);
+    return $extensions_wrapper->extensions;
+  }
+
+  static function get_upload_filters() {
+    $filters = array();
+    foreach (self::get_upload_extensions() as $extension) {
+      array_push($filters, "*." . $extension, "*." . strtoupper($extension));
+    }
+    return $filters;
+  }
+}
diff --git a/modules/gallery/helpers/system.php b/modules/gallery/helpers/system.php
index c39c7227..31ecafa7 100644
--- a/modules/gallery/helpers/system.php
+++ b/modules/gallery/helpers/system.php
@@ -40,4 +40,29 @@ class system_Core {
     }
     return null;
   }
+
+  /**
+   * Create a file with a unique file name.
+   * This helper is similar to the built-in tempnam, except that it supports an optional postfix.
+   */
+  static function tempnam($dir = TMPPATH, $prefix = "", $postfix = "") {
+    return self::_tempnam($dir, $prefix, $postfix, "tempnam");
+  }
+
+  // This helper provides a dependency-injected implementation of tempnam.
+  static function _tempnam($dir, $prefix, $postfix, $builtin) {
+    $success = false;
+    do {
+      $basename = call_user_func($builtin, $dir, $prefix);
+      if (!$basename) {
+        return false;
+      }
+      $filename = $basename . $postfix;
+      $success = !file_exists($filename) && @rename($basename, $filename);
+      if (!$success) {
+        @unlink($basename);
+      }
+    } while (!$success);
+    return $filename;
+  }
 }
\ No newline at end of file
diff --git a/modules/gallery/libraries/Form_Uploadify.php b/modules/gallery/libraries/Form_Uploadify.php
index 3e35e380..884653e2 100644
--- a/modules/gallery/libraries/Form_Uploadify.php
+++ b/modules/gallery/libraries/Form_Uploadify.php
@@ -47,6 +47,7 @@ class Form_Uploadify_Core extends Form_Input {
     $v->script_data = $this->data["script_data"];
     $v->simultaneous_upload_limit = module::get_var("gallery", "simultaneous_upload_limit");
     $v->movies_allowed = (bool) movie::find_ffmpeg();
+    $v->extensions = extensions::get_upload_filters();
     $v->suhosin_session_encrypt = (bool) ini_get("suhosin.session.encrypt");
 
     list ($toolkit_max_filesize_bytes, $toolkit_max_filesize) = graphics::max_filesize();
diff --git a/modules/gallery/models/item.php b/modules/gallery/models/item.php
index 2a5e6894..5ccbe75c 100644
--- a/modules/gallery/models/item.php
+++ b/modules/gallery/models/item.php
@@ -128,6 +128,15 @@ class Item_Model_Core extends ORM_MPTT {
   }
 
   /**
+   * Get the path to the data file associated with this item.
+   * This data file field is only set until you call save().
+   * After that, you can get the path using get_file_path().
+   */
+  public function get_data_file() {
+    return $this->data_file;
+  }
+
+  /**
    * Return the server-relative url to this item, eg:
    *   /gallery3/index.php/BobsWedding?page=2
    *   /gallery3/index.php/BobsWedding/Eating-Cake.jpg
@@ -408,6 +417,16 @@ class Item_Model_Core extends ORM_MPTT {
         // If any significant fields have changed, load up a copy of the original item and
         // keep it around.
         $original = ORM::factory("item", $this->id);
+
+        // Preserve the extension of the data file.
+        if (isset($this->data_file)) {
+          $extension = pathinfo($this->data_file, PATHINFO_EXTENSION);
+          $new_name = pathinfo($this->name, PATHINFO_FILENAME) . ".$extension";
+          if (!empty($extension) && strcmp($this->name, $new_name)) {
+            $this->name = $new_name;
+          }
+        }
+
         if (array_intersect($this->changed, array("parent_id", "name", "slug"))) {
           $original->_build_relative_caches();
           $this->relative_path_cache = null;
@@ -430,7 +449,10 @@ class Item_Model_Core extends ORM_MPTT {
 
         if ($original->parent_id != $this->parent_id || $original->name != $this->name) {
           // Move all of the items associated data files
-          @rename($original->file_path(), $this->file_path());
+          $this->_build_relative_caches();
+          if (!isset($this->data_file)) {
+            @rename($original->file_path(), $this->file_path());
+          }
           if ($this->is_album()) {
             @rename(dirname($original->resize_path()), dirname($this->resize_path()));
             @rename(dirname($original->thumb_path()), dirname($this->thumb_path()));
@@ -460,8 +482,6 @@ class Item_Model_Core extends ORM_MPTT {
         }
 
         // Replace the data file, if requested.
-        // @todo: we don't handle the case where you swap in a file of a different mime type
-        //        should we prevent that in validation?  or in set_data_file()
         if ($this->data_file && ($this->is_photo() || $this->is_movie())) {
           copy($this->data_file, $this->file_path());
 
@@ -481,6 +501,9 @@ class Item_Model_Core extends ORM_MPTT {
           // Null out the data file variable here, otherwise this event will trigger another
           // save() which will think that we're doing another file move.
           $this->data_file = null;
+          if ($original->file_path() != $this->file_path()) {
+            @unlink($original->file_path());
+          }
           module::event("item_updated_data_file", $this);
         }
       }
@@ -517,6 +540,8 @@ class Item_Model_Core extends ORM_MPTT {
         $this->name = "$base_name-$rand";
       }
       $this->slug = "$base_slug-$rand";
+      $this->relative_path_cache = null;
+      $this->relative_url_cache = null;
     }
   }
 
@@ -768,16 +793,7 @@ class Item_Model_Core extends ORM_MPTT {
     }
 
     if ($this->is_movie() || $this->is_photo()) {
-      if ($this->loaded()) {
-        // Existing items can't change their extension
-        $original = ORM::factory("item", $this->id);
-        $new_ext = pathinfo($this->name, PATHINFO_EXTENSION);
-        $old_ext = pathinfo($original->name, PATHINFO_EXTENSION);
-        if (strcasecmp($new_ext, $old_ext)) {
-          $v->add_error("name", "illegal_data_file_extension");
-          return;
-        }
-      } else {
+      if (!$this->loaded()) {
         // New items must have an extension
         $ext = pathinfo($this->name, PATHINFO_EXTENSION);
         if (!$ext) {
@@ -785,9 +801,11 @@ class Item_Model_Core extends ORM_MPTT {
           return;
         }
 
-        if ($this->is_movie() && !preg_match("/^(flv|mp4|m4v)$/i", $ext)) {
-          $v->add_error("name", "illegal_data_file_extension");
-        } else if ($this->is_photo() && !preg_match("/^(gif|jpg|jpeg|png)$/i", $ext)) {
+        if (($this->is_movie() || $this->is_photo()) &&
+            !preg_match("/^(" .
+                        implode("|", array_map("preg_quote",
+                                               extensions::get_upload_extensions())) .
+                        ")\$/i", $ext)) {
           $v->add_error("name", "illegal_data_file_extension");
         }
       }
@@ -813,17 +831,6 @@ class Item_Model_Core extends ORM_MPTT {
     } else if (filesize($this->data_file) == 0) {
       $v->add_error("name", "empty_data_file");
     }
-
-    if ($this->loaded()) {
-      if ($this->is_photo()) {
-        list ($a, $b, $mime_type) = photo::get_file_metadata($this->data_file);
-      } else if ($this->is_movie()) {
-        list ($a, $b, $mime_type) = movie::get_file_metadata($this->data_file);
-      }
-      if ($mime_type != $this->mime_type) {
-        $v->add_error("name", "cant_change_mime_type");
-      }
-    }
   }
 
   /**
@@ -879,7 +886,7 @@ class Item_Model_Core extends ORM_MPTT {
       if ($this->is_movie()) {
         $legal_values = array("video/flv", "video/x-flv", "video/mp4");
       } if ($this->is_photo()) {
-        $legal_values = array("image/jpeg", "image/gif", "image/png");
+        $legal_values = array("image/jpeg", "image/gif", "image/png", "image/tiff");
       }
       break;
 
diff --git a/modules/gallery/tests/Mock_Built_In.php b/modules/gallery/tests/Mock_Built_In.php
new file mode 100644
index 00000000..b02e5ecf
--- /dev/null
+++ b/modules/gallery/tests/Mock_Built_In.php
@@ -0,0 +1,39 @@
+<?php defined("SYSPATH") or die("No direct script access.");
+/**
+ * Gallery - a web based photo album viewer and editor
+ * Copyright (C) 2011 Chad Parry
+ *
+ * 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., 51 Franklin Street - Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+/**
+ * Deterministic replacement for the built-in tempnam function.
+ * This is useful in unit tests where a dependency on tempnam needs to be mocked.
+ */
+class Mock_Built_In {
+  private $nonces;
+
+  function __construct() {
+    $this->nonces = func_get_args();
+  }
+
+  function _tempnam($dir, $prefix) {
+    if (empty($this->nonces))
+      return false;
+    $filename = "$dir/$prefix" . array_shift($this->nonces);
+    if (!touch($filename))
+      return false;
+    return $filename;
+  }
+}
diff --git a/modules/gallery/tests/System_Helper_Test.php b/modules/gallery/tests/System_Helper_Test.php
new file mode 100644
index 00000000..734f98ac
--- /dev/null
+++ b/modules/gallery/tests/System_Helper_Test.php
@@ -0,0 +1,49 @@
+<?php defined("SYSPATH") or die("No direct script access.");
+/**
+ * Gallery - a web based photo album viewer and editor
+ * Copyright (C) 2011 Chad Parry
+ *
+ * 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., 51 Franklin Street - Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+class System_Helper_Test extends Gallery_Unit_Test_Case {
+  public function tempnam_random_test() {
+    $filename = system::tempnam(TMPPATH, "file", ".ext");
+    $this->assert_true(file_exists($filename), "File not created");
+    unlink($filename);
+  }
+
+  public function tempnam_collision_test() {
+    require_once('Mock_Built_In.php');
+    $existing = TMPPATH . "/file1.ext";
+    $available = TMPPATH . "/file2.ext";
+    touch($existing);
+    $filename = system::_tempnam(TMPPATH, "file", ".ext",
+                                 array(new Mock_Built_In("1", "2"), "_tempnam"));
+    unlink($existing);
+    $this->assert_true(file_exists($filename), "File not created");
+    unlink($filename);
+    $this->assert_equal($available, $filename, "Incorrect filename created");
+  }
+
+  public function tempnam_abort_test() {
+    require_once('Mock_Built_In.php');
+    $filename = system::_tempnam(TMPPATH, "file", ".ext",
+                                 array(new Mock_Built_In(), "_tempnam"));
+    if ($filename) {
+      @unlink($filename);
+    }
+    $this->assert_false($filename, "Operation not aborted");
+  }
+}
diff --git a/modules/gallery/views/form_uploadify.html.php b/modules/gallery/views/form_uploadify.html.php
index 83dfcc68..ba4a3621 100644
--- a/modules/gallery/views/form_uploadify.html.php
+++ b/modules/gallery/views/form_uploadify.html.php
@@ -28,7 +28,7 @@
         uploader: "<?= url::file("lib/uploadify/uploadify.swf") ?>",
         script: "<?= url::site("uploader/add_photo/{$album->id}") ?>",
         scriptData: <?= json_encode($script_data) ?>,
-        fileExt: "*.gif;*.jpg;*.jpeg;*.png;*.GIF;*.JPG;*.JPEG;*.PNG<? if ($movies_allowed): ?>;*.flv;*.mp4;*.m4v;*.FLV;*.MP4;*.M4V<? endif ?>",
+        fileExt: "<?= implode(";", $extensions) ?>",
         fileDesc: <?= t("Photos and movies")->for_js() ?>,
         cancelImg: "<?= url::file("lib/uploadify/cancel.png") ?>",
         simUploadLimit: <?= $simultaneous_upload_limit ?>,