AttachmentSystem for NAT file processing

src/nat/ArchiveController.kiss

@@ -152,6 +152,9 @@
     // Add systems!
     (archive.addSystem nameSystem)
     (archive.addSystem (new WikipediaImageSystem))
+    // Just for testing:
+    (archive.addSystem (new AttachmentSystem ["jpg" "jpeg" "png"] ->[archive e files] ~files))
+
     (archive.processSystems)
     
     (defCommand Help []

src/nat/systems/AttachmentSystem.hx

@@ -0,0 +1,17 @@
+package nat.systems;
+
+import kiss.Prelude;
+import kiss.List;
+import nat.System;
+import haxe.Json;
+
+using haxe.io.Path;
+
+typedef AttachmentProcessor = (Archive, Entry, Array<String>) -> Dynamic;
+
+/**
+ * Base System that processes Entries based on whether they have file attachments
+ * which match a given set of extensions
+ */
+@:build(kiss.Kiss.build())
+class AttachmentSystem extends System {}

src/nat/systems/AttachmentSystem.kiss

@@ -0,0 +1,14 @@
+(load "../Lib.kiss")
+
+(defNew [&prop :Array<String> extensions
+            :AttachmentProcessor processor] 
+    (super
+        ->[archive e]
+            {
+                (doFor file e.files
+                    (when !(= -1 (extensions.indexOf (file.extension)))
+                        (return true)))
+                false
+            }
+        ->[archive e]
+            (processor archive e (filter e.files ->file !(= -1 (extensions.indexOf (file.extension)))))))