Add 'dotscape/' from commit 'f306501a68a51b634e895c5fdac70788ae899d75'

git-subtree-dir: dotscape
git-subtree-mainline: 6b91d64fc3
git-subtree-split: f306501a68

dotscape/imperative-shell/file-thread.sml

@@ -0,0 +1,54 @@
+signature FILE_THREAD =
+sig
+  val run: FileMessage.t Mailbox.mbox * InputMessage.t Mailbox.mbox -> unit
+end
+
+structure FileThread :> FILE_THREAD =
+struct
+  open FileMessage
+  open InputMessage
+
+  fun loadIO (io, str) =
+    case TextIO.inputLine io of
+      SOME line => loadIO (io, str ^ line)
+    | NONE => str
+
+  fun loadSquares (path, inputMailbox) =
+    let
+      val io = TextIO.openIn path
+      val str = loadIO (io, "")
+      val () = TextIO.closeIn io
+    in
+      case Parser.parse str of
+        SOME (canvasWidth, canvasHeight, tree) =>
+          Mailbox.send
+            ( inputMailbox
+            , USE_LAYERS
+                { tree = tree
+                , canvasWidth = canvasWidth
+                , canvasHeight = canvasHeight
+                }
+            )
+      | NONE => ()
+    end
+
+  fun saveString (filename, toSaveString) =
+    let
+      val io = TextIO.openOut filename
+      val () = TextIO.output (io, toSaveString)
+    in
+      TextIO.closeOut io
+    end
+
+  fun run (fileMailbox, inputMailbox) =
+    let
+      val _ =
+        case Mailbox.recv fileMailbox of
+          SAVE_SQUARES {filepath, output} => saveString (filepath, output)
+        | EXPORT_SQUARES {filepath, output} => saveString (filepath, output)
+        | EXPORT_COLLISIONS {filepath, output} => saveString (filepath, output)
+        | LOAD_SQUARES {filepath} => loadSquares (filepath, inputMailbox)
+    in
+      run (fileMailbox, inputMailbox)
+    end
+end