concept SFEditor {

  // What are we editing?

  O editing; // File or snippet ID

  S remoteText;

  S savedText;

  int caretPos;

  int fontSize = 16;

  S fontID = /*#1400030*/#1400031;

  S snippetTitle;

  transient EditorFrame e;

  transient SimpleLiveValue<O> lvEditing;

  transient AutoCompletion autoCompletion;

  transient ReliableSingleThread rstAutoComplete = new(r installAutoComplete);

  transient bool installAutoComplete_first;

  transient Set<S> autoComplete_lastSet;

  transient DynamicHStack smartArea;

  transient int autoCompleteRefreshDelay = 1000;

  transient JTextArea transpilationErrorBox;

  !include #1015622 // setAndSave etc.

  void reset {

    cleanMeUp();

    autoCompletion = null;

    autoComplete_lastSet = null;

    start();

  }

  void start { swing {

    installAutoComplete_first = true;

    lvEditing = new SimpleLiveValue(O);

    e = new EditorFrame;

    e._setFont(deriveFont(loadFont(fontID), e._getFont().getSize()));

    e._setFontSize(fontSize);

    rstAutoComplete.trigger();

    onChange(e.textArea, rTrigger(rstAutoComplete));

    addToWindowWithMargin(e, jHigherScrollPane(jfullcenter(smartArea = dynamicHStack())));

    e.setText(savedText);

    load('caretPos);

    setCaretPosition(e.textArea, caretPos);

    showFrame(e);

    frameIcon(e, #1101185 /*#1004655*/);

    addFontChangersToTitleMenu(e, r reset);

    onFrameClosing(e, r {

      if (!cleaningUp())

        deleteConcept(SFEditor.this);

    });

    addMenu(e, "&New",

      "New text", r newText,

      "New window", r newWindow);

    addMenu(e, "&Load", "Load snippet...", r {

      selectSnippetID(voidfunc(S snippetID) { _loadSnippet(snippetID) });

    }, "Load file...", r {

      selectFile("File to load", voidfunc(File f) { _loadFile(f) });

    }, "Reload", r-thread { // TODO: single thread

      if (editing != null) {

        reload();

        setText(e.textArea, remoteText);

      }

    });

    LiveValue<S> lvSaveCmd = mapLiveValue(func(O editing) -> S {

      editing instanceof S ? "Save snippet " + editing

        : editing instanceof File ? "Save file " + f2s((File) editing)

        : "{Save}" }, S.class, lvEditing);

    addMenu(e, "&Save",

      lvSaveCmd, r { saveThen(null) },

      "Save as snippet...", r saveAsSnippet);

    addMenu(e, "&Transpile",

      "Save & Quick Transpile", r { transpile(false) },

      "Save & Medium Transpile", r { transpile(true) });

    addMenu(e, "&Activate",

      "Run", r runIt,

      "Butter-Reload", r _butterReload);

    addMenu(e, "&View",

      "Bigger font", r { e._setFontSize(setAndSave(fontSize := e._getFontSize()+1)) },

      "Smaller font", r { e._setFontSize(setAndSave(fontSize := max(1, e._getFontSize()-1))) });

    reload();

    awtCalcEvery(e, 1000, r update);

    onFrameDeactivated(e, r fullUpdate);

  }

}

  void reload {

    if (editing instanceof S) _loadSnippet_noSet((S) editing);

    else if (editing instanceof File) _loadFile_noSet((File) editing);

  }

  void update { update(windowActive(e)); }

  void fullUpdate { update(true); }

  void update(bool full) {

    S text = e.getText();

    setAndSaveIfChanged(savedText := text);

    setAndSaveIfChanged(caretPos := getCaretPosition(e.textArea));

    if (!full) ret;

    S status = remoteText != null && neq(remoteText, text) ? "Changes. " : "";

    Pair<Int, S> p = testBracketHygieneExt(text);

    status += p == null ? "Hygienic" : p.b;

    silentStatus(trim(status));

  }

  void status(S s) { silentStatus(infoBoxAndReturn(s)); }

  void silentStatus(S s) { e.setStatus(s); }

  void saveThen(final Runnable next) {

    fS text = getText();

    if (editing instanceof S) {

      status("Saving snippet...");

      thread {

        fS page = editSnippet((S) editing, text);

        remoteText = text; // TODO: check save result

        status("Saved snippet: " + page);

        awtCallF(next);

      }

    } else if (editing instanceof File) {

      status("Saving file...");

      thread {

        saveTextFile((File) editing, text);

        remoteText = text;

        status("Saved file");

        awtCallF(next);

      }

    }

  }

  void _butterReload() {

    time { butterReload((S) editing); }

    infoBox("Reloaded in " + lastTiming_format100ms());

  }

  void transpile(final bool medium) { saveThen(r { _transpile(medium) }); }

  void _transpile(final bool medium) {

    status("Transpiling...");

    //jdisable(btnEleuReload);

    thread "Transpiling" {

      try {

        final Pair<Bool, S> p = transpileOnServer((S) editing, medium ? "medium" : "quick");

        awt {

          if (p.a) {

            status("Transpiled OK!");

            hideWindow(transpilationErrorBox);

            transpilationErrorBox = null;

          } else {

            status("Transpilation error. " + p.b);

            bool first = transpilationErrorBox == null;

            transpilationErrorBox = showText(transpilationErrorBox, "Transpilation Error", p.b);

            if (first) {

              setFrameIcon(#1101268, transpilationErrorBox);

              addButtonsToWindow(transpilationErrorBox, "Medium transpile", r { _transpile(true) });

            }

          }

        }

      } catch print e {

        status("Transpilation problem. " + e);

      }

      //jenable(btnEleuReload);

    }

  }

  void _loadSnippet(S snippetID) {

    _loadSnippet_noSet(snippetID);

    e.textArea.setText(remoteText);

  }

  void _loadSnippet_noSet(S snippetID) {

    remoteText = loadSnippet(snippetID);

    setAndSave('editing, snippetID);

    lvEditing.set(snippetID);

    frameTitle(e, snippetID + " - " + (snippetTitle = snippetTitle(snippetID)));

  }

  void _loadFile(File f) {

    _loadFile_noSet(f);

    e.textArea.setText(remoteText);

  }

  void _loadFile_noSet(File f) {

    remoteText = loadTextFile(f);

    setAndSave('editing, f);

    lvEditing.set(f);

    frameTitle(e, f2s(f));

  }

  void newText {

    setAndSave(editing := null);

    lvEditing.set(null);

    remoteText = null;

    S lastText = e.getText();

    if (nempty(lastText)) logQuotedWithDate("saved-texts.log", lastText);

    e.setText("");

    frameTitle(e, programTitle());

  }

  void cleanMeUp {

    update(false);

    disposeWindow(e);

  }

  void installAutoComplete {

    if (installAutoComplete_first) installAutoComplete_first = false;

    else sleep(autoCompleteRefreshDelay); // don't update too often

    //temp tempMiniLoadingAnim();

    Set<S> set = concatListsToSet(allJavaKeywords(), standardFunctionNames(), deepWords(getText()), deepWords(snippetTitle));

    if (eq(set, autoComplete_lastSet)) ret;

    autoComplete_lastSet = set;

    final new DefaultCompletionProvider provider;

    provider.addCompletions(map(func(S s) { new BasicCompletion(provider, s) }, set));

    swing {

      if (autoCompletion == null) {

        (autoCompletion = new AutoCompletion(provider)).install(e.textArea);

        call(autoCompletion, 'setHideOnCompletionProviderChange, false);

      } else

        autoCompletion.setCompletionProvider(provider);

    }

  }

  void newWindow {

    copyFields(this, new SFEditor(), 'fontSize).start();

  }

  void runIt {

    if (editing instanceof S)

      nohupJavax((S) editing);

  }

  void saveAsSnippet {

    final JTextField tfTitle = jtextfield();

    final JComboBox cbType = jComboBox_javaxTypes();

    showFormTitled("Save as new snippet",

      "Title:", tfTitle,

      "Type:", cbType,

      r-thread {

        loading {

          int type = parseFirstInt(getSelectedItem(cbType));

          S title = getTextTrim(tfTitle);

          S snippetID = createSnippet(getText(), title, type);

          _loadSnippet_noSet(snippetID);

        }

      });

  }

  S getText() { ret e.getText(); }

}