add js save dialog

webgl/src/mylib.js

@@ -15,14 +15,46 @@ function js_pick_file(fn) {
         console.log("reader.onload " + file.name);
         var content = new Uint8Array(readerEvent.target.result); // this is the content!
         console.log( content );
-        FS.writeFile(file.name, content);
-        Module.TaskCallback_call(fn, file.name);
-        Module.TaskCallback_delete(fn);
+        FS.writeFile("/" + file.name, content);
+        Module.TaskCallback_open_call(fn, "/" + file.name);
+        Module.TaskCallback_open_delete(fn);
       }
     }
     
     input.click();
 }
+function js_pick_file_save(path, name, fn) {
+  jspath = Module.UtilityGetString(path);
+  jsname = Module.UtilityGetString(name);
+  console.log("js_pick_file_save");
+  console.log(jspath);
+  file = FS.readFile(jspath);
+  blob = new Blob([file]);
+  console.log(file);
+
+  // IE hack;
+  // see: http://msdn.microsoft.com/en-us/library/ie/hh779016.aspx
+  if (window.navigator.msSaveOrOpenBlob)
+  {
+    window.navigator.msSaveBlob(blob, jsname);
+  }
+  else
+  {
+    var a = window.document.createElement("a");
+    a.href = window.URL.createObjectURL(blob, {type: "application/octet-stream"});
+    a.download = jsname;
+    document.body.appendChild(a);
+    // IE: "Access is denied"; 
+    // see: https://connect.microsoft.com/IE/feedback/details/797361/ie-10-treats-blob-url-as-cross-origin-and-denies-access
+    a.click();
+    document.body.removeChild(a);
+  }
+
+  Module.TaskCallback_save_call(fn, true);
+  Module.TaskCallback_save_delete(fn);
+}
+
 mergeInto(LibraryManager.library, {
   js_pick_file: js_pick_file,
+  js_pick_file_save: js_pick_file_save,
 });