+ * If true, emit thread stuff to System.err.
+ */
+ private static final boolean debugThreads = false;
+
+ /**
+ * WidgetEventHandler is the main event consumer loop. There are at most
+ * two such threads in existence: the primary for normal case and a
+ * secondary that is used for TMessageBox, TInputBox, and similar.
+ */
+ private class WidgetEventHandler implements Runnable {
+ /**
+ * The main application.
+ */
+ private TApplication application;
+
+ /**
+ * Whether or not this WidgetEventHandler is the primary or secondary
+ * thread.
+ */
+ private boolean primary = true;
+
+ /**
+ * Public constructor.
+ *
+ * @param application the main application
+ * @param primary if true, this is the primary event handler thread
+ */
+ public WidgetEventHandler(final TApplication application,
+ final boolean primary) {
+
+ this.application = application;
+ this.primary = primary;
+ }
+
+ /**
+ * The consumer loop.
+ */
+ public void run() {
+
+ // Loop forever
+ while (!application.quit) {
+
+ // Wait until application notifies me
+ while (!application.quit) {
+ try {
+ synchronized (application.drainEventQueue) {
+ if (application.drainEventQueue.size() > 0) {
+ break;
+ }
+ }
+ synchronized (application) {
+ application.wait();
+ if ((!primary)
+ && (application.secondaryEventReceiver == null)
+ ) {
+ // Secondary thread, time to exit
+ return;
+ }
+ break;
+ }
+ } catch (InterruptedException e) {
+ // SQUASH
+ }
+ }
+
+ // Pull all events off the queue
+ for (;;) {
+ TInputEvent event = null;
+ synchronized (application.drainEventQueue) {
+ if (application.drainEventQueue.size() == 0) {
+ break;
+ }
+ event = application.drainEventQueue.remove(0);
+ }
+ // Wait for drawAll() or doIdle() to be done, then handle
+ // the event.
+ boolean oldLock = lockHandleEvent();
+ assert (oldLock == false);
+ if (primary) {
+ primaryHandleEvent(event);
+ } else {
+ secondaryHandleEvent(event);
+ }
+ if ((!primary)
+ && (application.secondaryEventReceiver == null)
+ ) {
+ // Secondary thread, time to exit.
+
+ // DO NOT UNLOCK. Primary thread just came back from
+ // primaryHandleEvent() and will unlock in the else
+ // block below.
+ return;
+ } else {
+ // Unlock. Either I am primary thread, or I am
+ // secondary thread and still running.
+ oldLock = unlockHandleEvent();
+ assert (oldLock == true);
+ }
+ }
+ } // while (true) (main runnable loop)
+ }
+ }
+
+ /**
+ * The primary event handler thread.
+ */
+ private WidgetEventHandler primaryEventHandler;
+
+ /**
+ * The secondary event handler thread.
+ */
+ private WidgetEventHandler secondaryEventHandler;
+
+ /**
+ * The widget receiving events from the secondary event handler thread.
+ */
+ private TWidget secondaryEventReceiver;
+
+ /**
+ * Spinlock for the primary and secondary event handlers.
+ * WidgetEventHandler.run() is responsible for setting this value.
+ */
+ private volatile boolean insideHandleEvent = false;
+
+ /**
+ * Set the insideHandleEvent flag to true. lockoutEventHandlers() will
+ * spin indefinitely until unlockHandleEvent() is called.
+ *
+ * @return the old value of insideHandleEvent
+ */
+ private boolean lockHandleEvent() {
+ if (debugThreads) {
+ System.err.printf(" >> lockHandleEvent(): oldValue %s",
+ insideHandleEvent);
+ }
+ boolean oldValue = true;
+
+ synchronized (this) {
+ // Wait for TApplication.run() to finish using the global state
+ // before allowing further event processing.
+ while (lockoutHandleEvent == true);
+
+ oldValue = insideHandleEvent;
+ insideHandleEvent = true;
+ }
+
+ if (debugThreads) {
+ System.err.printf(" ***\n");
+ }
+ return oldValue;
+ }
+
+ /**
+ * Set the insideHandleEvent flag to false. lockoutEventHandlers() will
+ * spin indefinitely until unlockHandleEvent() is called.
+ *
+ * @return the old value of insideHandleEvent
+ */
+ private boolean unlockHandleEvent() {
+ if (debugThreads) {
+ System.err.printf(" << unlockHandleEvent(): oldValue %s\n",
+ insideHandleEvent);
+ }
+ synchronized (this) {
+ boolean oldValue = insideHandleEvent;
+ insideHandleEvent = false;
+ return oldValue;
+ }
+ }
+
+ /**
+ * Spinlock for the primary and secondary event handlers. When true, the
+ * event handlers will spinlock wait before calling handleEvent().
+ */
+ private volatile boolean lockoutHandleEvent = false;
+
+ /**
+ * TApplication.run() needs to be able rely on the global data structures
+ * being intact when calling doIdle() and drawAll(). Tell the event
+ * handlers to wait for an unlock before handling their events.
+ */
+ private void stopEventHandlers() {
+ if (debugThreads) {
+ System.err.printf(">> stopEventHandlers()");
+ }
+
+ lockoutHandleEvent = true;
+ // Wait for the last event to finish processing before returning
+ // control to TApplication.run().
+ while (insideHandleEvent == true);
+
+ if (debugThreads) {
+ System.err.printf(" XXX\n");
+ }
+ }
+
+ /**
+ * TApplication.run() needs to be able rely on the global data structures
+ * being intact when calling doIdle() and drawAll(). Tell the event
+ * handlers that it is now OK to handle their events.
+ */
+ private void startEventHandlers() {
+ if (debugThreads) {
+ System.err.printf("<< startEventHandlers()\n");
+ }
+ lockoutHandleEvent = false;
+ }
+
+ /**
+ * Access to the physical screen, keyboard, and mouse.
+ */
+ private Backend backend;
+
+ /**
+ * Get the Screen.
+ *
+ * @return the Screen
+ */
+ public final Screen getScreen() {
+ return backend.getScreen();
+ }
+
+ /**
+ * Actual mouse coordinate X.
+ */
+ private int mouseX;
+
+ /**
+ * Actual mouse coordinate Y.
+ */
+ private int mouseY;
+
+ /**
+ * Event queue that is filled by run().
+ */
+ private List<TInputEvent> fillEventQueue;
+
+ /**
+ * Event queue that will be drained by either primary or secondary
+ * Thread.
+ */
+ private List<TInputEvent> drainEventQueue;
+
+ /**
+ * Top-level menus in this application.
+ */
+ private List<TMenu> menus;
+
+ /**
+ * Stack of activated sub-menus in this application.
+ */
+ private List<TMenu> subMenus;
+
+ /**
+ * The currently acive menu.
+ */
+ private TMenu activeMenu = null;
+
+ /**
+ * Active keyboard accelerators.
+ */
+ private Map<TKeypress, TMenuItem> accelerators;
+
+ /**
+ * Windows and widgets pull colors from this ColorTheme.
+ */
+ private ColorTheme theme;
+
+ /**
+ * Get the color theme.
+ *
+ * @return the theme
+ */
+ public final ColorTheme getTheme() {
+ return theme;
+ }
+
+ /**
+ * The top-level windows (but not menus).
+ */
+ private List<TWindow> windows;
+
+ /**
+ * Timers that are being ticked.
+ */
+ private List<TTimer> timers;
+
+ /**
+ * When true, exit the application.
+ */
+ private boolean quit = false;
+
+ /**
+ * When true, repaint the entire screen.
+ */
+ private boolean repaint = true;
+
+ /**
+ * Request full repaint on next screen refresh.
+ */
+ public final void setRepaint() {
+ repaint = true;
+ }
+
+ /**
+ * When true, just flush updates from the screen.
+ */
+ private boolean flush = false;
+
+ /**
+ * Y coordinate of the top edge of the desktop. For now this is a
+ * constant. Someday it would be nice to have a multi-line menu or
+ * toolbars.
+ */
+ private static final int desktopTop = 1;
+
+ /**
+ * Get Y coordinate of the top edge of the desktop.
+ *
+ * @return Y coordinate of the top edge of the desktop
+ */
+ public final int getDesktopTop() {
+ return desktopTop;
+ }
+
+ /**
+ * Y coordinate of the bottom edge of the desktop.
+ */
+ private int desktopBottom;
+
+ /**
+ * Get Y coordinate of the bottom edge of the desktop.
+ *
+ * @return Y coordinate of the bottom edge of the desktop
+ */
+ public final int getDesktopBottom() {
+ return desktopBottom;
+ }
+
+ /**
+ * Public constructor.
+ *
+ * @param input an InputStream connected to the remote user, or null for
+ * System.in. If System.in is used, then on non-Windows systems it will
+ * be put in raw mode; shutdown() will (blindly!) put System.in in cooked
+ * mode. input is always converted to a Reader with UTF-8 encoding.
+ * @param output an OutputStream connected to the remote user, or null
+ * for System.out. output is always converted to a Writer with UTF-8
+ * encoding.
+ * @throws UnsupportedEncodingException if an exception is thrown when
+ * creating the InputStreamReader
+ */
+ public TApplication(final InputStream input,
+ final OutputStream output) throws UnsupportedEncodingException {
+
+ // AWT is the default backend on Windows unless explicitly overridden
+ // by jexer.AWT.
+ boolean useAWT = false;
+ if (System.getProperty("os.name").startsWith("Windows")) {
+ useAWT = true;
+ }
+ if (System.getProperty("jexer.AWT") != null) {
+ if (System.getProperty("jexer.AWT", "false").equals("true")) {
+ useAWT = true;
+ } else {
+ useAWT = false;
+ }
+ }
+
+
+ if (useAWT) {
+ backend = new AWTBackend();
+ } else {
+ backend = new ECMA48Backend(input, output);
+ }
+ theme = new ColorTheme();
+ desktopBottom = getScreen().getHeight() - 1;
+ fillEventQueue = new ArrayList<TInputEvent>();
+ drainEventQueue = new ArrayList<TInputEvent>();
+ windows = new LinkedList<TWindow>();
+ menus = new LinkedList<TMenu>();
+ subMenus = new LinkedList<TMenu>();
+ timers = new LinkedList<TTimer>();
+ accelerators = new HashMap<TKeypress, TMenuItem>();
+
+ // Setup the main consumer thread
+ primaryEventHandler = new WidgetEventHandler(this, true);
+ (new Thread(primaryEventHandler)).start();
+ }
+
+ /**
+ * Invert the cell at the mouse pointer position.
+ */
+ private void drawMouse() {
+ CellAttributes attr = getScreen().getAttrXY(mouseX, mouseY);
+ attr.setForeColor(attr.getForeColor().invert());
+ attr.setBackColor(attr.getBackColor().invert());
+ getScreen().putAttrXY(mouseX, mouseY, attr, false);
+ flush = true;
+
+ if (windows.size() == 0) {
+ repaint = true;
+ }
+ }
+
+ /**
+ * Draw everything.
+ */
+ public final void drawAll() {
+ if (debugThreads) {
+ System.err.printf("drawAll() enter\n");
+ }
+
+ if ((flush) && (!repaint)) {
+ backend.flushScreen();
+ flush = false;
+ return;
+ }
+
+ if (!repaint) {
+ return;
+ }
+
+ if (debugThreads) {
+ System.err.printf("drawAll() REDRAW\n");
+ }
+
+ // If true, the cursor is not visible
+ boolean cursor = false;
+
+ // Start with a clean screen
+ getScreen().clear();
+
+ // Draw the background
+ CellAttributes background = theme.getColor("tapplication.background");
+ getScreen().putAll(GraphicsChars.HATCH, background);
+
+ // Draw each window in reverse Z order
+ List<TWindow> sorted = new LinkedList<TWindow>(windows);
+ Collections.sort(sorted);
+ Collections.reverse(sorted);
+ for (TWindow window: sorted) {
+ window.drawChildren();
+ }
+
+ // Draw the blank menubar line - reset the screen clipping first so
+ // it won't trim it out.
+ getScreen().resetClipping();
+ getScreen().hLineXY(0, 0, getScreen().getWidth(), ' ',
+ theme.getColor("tmenu"));
+ // Now draw the menus.
+ int x = 1;
+ for (TMenu menu: menus) {
+ CellAttributes menuColor;
+ CellAttributes menuMnemonicColor;
+ if (menu.getActive()) {
+ menuColor = theme.getColor("tmenu.highlighted");
+ menuMnemonicColor = theme.getColor("tmenu.mnemonic.highlighted");
+ } else {
+ menuColor = theme.getColor("tmenu");
+ menuMnemonicColor = theme.getColor("tmenu.mnemonic");
+ }
+ // Draw the menu title
+ getScreen().hLineXY(x, 0, menu.getTitle().length() + 2, ' ',
+ menuColor);
+ getScreen().putStrXY(x + 1, 0, menu.getTitle(), menuColor);
+ // Draw the highlight character
+ getScreen().putCharXY(x + 1 + menu.getMnemonic().getShortcutIdx(),
+ 0, menu.getMnemonic().getShortcut(), menuMnemonicColor);
+
+ if (menu.getActive()) {
+ menu.drawChildren();
+ // Reset the screen clipping so we can draw the next title.
+ getScreen().resetClipping();
+ }
+ x += menu.getTitle().length() + 2;
+ }
+
+ for (TMenu menu: subMenus) {
+ // Reset the screen clipping so we can draw the next sub-menu.
+ getScreen().resetClipping();
+ menu.drawChildren();
+ }
+
+ // Draw the mouse pointer
+ drawMouse();
+
+ // Place the cursor if it is visible
+ TWidget activeWidget = null;
+ if (sorted.size() > 0) {
+ activeWidget = sorted.get(sorted.size() - 1).getActiveChild();
+ if (activeWidget.visibleCursor()) {
+ getScreen().putCursor(true, activeWidget.getCursorAbsoluteX(),
+ activeWidget.getCursorAbsoluteY());
+ cursor = true;
+ }
+ }
+
+ // Kill the cursor
+ if (!cursor) {
+ getScreen().hideCursor();
+ }
+
+ // Flush the screen contents
+ backend.flushScreen();
+
+ repaint = false;
+ flush = false;
+ }
+
+ /**
+ * Run this application until it exits.
+ */
+ public final void run() {
+ while (!quit) {
+ // Timeout is in milliseconds, so default timeout after 1 second
+ // of inactivity.
+ int timeout = getSleepTime(1000);
+
+ // See if there are any definitely events waiting to be processed
+ // or a screen redraw to do. If so, do not wait if there is no
+ // I/O coming in.
+ synchronized (drainEventQueue) {
+ if (drainEventQueue.size() > 0) {
+ timeout = 0;
+ }
+ }
+ synchronized (fillEventQueue) {
+ if (fillEventQueue.size() > 0) {
+ timeout = 0;
+ }
+ }
+
+ // Pull any pending I/O events
+ backend.getEvents(fillEventQueue, timeout);
+
+ // Dispatch each event to the appropriate handler, one at a time.
+ for (;;) {
+ TInputEvent event = null;
+ synchronized (fillEventQueue) {
+ if (fillEventQueue.size() == 0) {
+ break;
+ }
+ event = fillEventQueue.remove(0);
+ }
+ metaHandleEvent(event);
+ }
+
+ // Prevent stepping on the primary or secondary event handler.
+ stopEventHandlers();
+
+ // Process timers and call doIdle()'s
+ doIdle();
+
+ // Update the screen
+ synchronized (getScreen()) {
+ drawAll();
+ }
+
+ // Let the event handlers run again.
+ startEventHandlers();
+ }
+
+ // Shutdown the consumer threads
+ synchronized (this) {
+ this.notifyAll();
+ }
+
+ backend.shutdown();
+ }
+
+ /**
+ * Peek at certain application-level events, add to eventQueue, and wake
+ * up the consuming Thread.
+ *
+ * @param event the input event to consume
+ */
+ private void metaHandleEvent(final TInputEvent event) {
+
+ /*
+ System.err.printf(String.format("metaHandleEvents event: %s\n",
+ event)); System.err.flush();
+ */
+
+ if (quit) {
+ // Do no more processing if the application is already trying
+ // to exit.
+ return;
+ }
+
+ // Special application-wide events -------------------------------
+
+ // Abort everything
+ if (event instanceof TCommandEvent) {
+ TCommandEvent command = (TCommandEvent) event;
+ if (command.getCmd().equals(cmAbort)) {
+ quit = true;
+ return;
+ }
+ }
+
+ // Screen resize
+ if (event instanceof TResizeEvent) {
+ TResizeEvent resize = (TResizeEvent) event;
+ getScreen().setDimensions(resize.getWidth(),
+ resize.getHeight());
+ desktopBottom = getScreen().getHeight() - 1;
+ repaint = true;
+ mouseX = 0;
+ mouseY = 0;
+ return;
+ }
+
+ // Peek at the mouse position
+ if (event instanceof TMouseEvent) {
+ TMouseEvent mouse = (TMouseEvent) event;
+ if ((mouseX != mouse.getX()) || (mouseY != mouse.getY())) {
+ mouseX = mouse.getX();
+ mouseY = mouse.getY();
+ drawMouse();
+ }
+ }
+
+ // Put into the main queue
+ synchronized (drainEventQueue) {
+ drainEventQueue.add(event);
+ }
+
+ // Wake all threads: primary thread will either be consuming events
+ // again or waiting in yield(), and secondary thread will either not
+ // exist or consuming events.
+ synchronized (this) {
+ this.notifyAll();
+ }
+ }
+
+ /**
+ * Dispatch one event to the appropriate widget or application-level
+ * event handler. This is the primary event handler, it has the normal
+ * application-wide event handling.
+ *
+ * @param event the input event to consume
+ * @see #secondaryHandleEvent(TInputEvent event)
+ */
+ private void primaryHandleEvent(final TInputEvent event) {
+
+ // System.err.printf("Handle event: %s\n", event);
+
+ // Special application-wide events -----------------------------------
+
+ // Peek at the mouse position
+ if (event instanceof TMouseEvent) {
+ // See if we need to switch focus to another window or the menu
+ checkSwitchFocus((TMouseEvent) event);
+ }
+
+ // Handle menu events
+ if ((activeMenu != null) && !(event instanceof TCommandEvent)) {
+ TMenu menu = activeMenu;
+
+ if (event instanceof TMouseEvent) {
+ TMouseEvent mouse = (TMouseEvent) event;
+
+ while (subMenus.size() > 0) {
+ TMenu subMenu = subMenus.get(subMenus.size() - 1);
+ if (subMenu.mouseWouldHit(mouse)) {
+ break;
+ }
+ if ((mouse.getType() == TMouseEvent.Type.MOUSE_MOTION)
+ && (!mouse.getMouse1())
+ && (!mouse.getMouse2())
+ && (!mouse.getMouse3())
+ && (!mouse.getMouseWheelUp())
+ && (!mouse.getMouseWheelDown())
+ ) {
+ break;
+ }
+ // We navigated away from a sub-menu, so close it
+ closeSubMenu();
+ }
+
+ // Convert the mouse relative x/y to menu coordinates
+ assert (mouse.getX() == mouse.getAbsoluteX());
+ assert (mouse.getY() == mouse.getAbsoluteY());
+ if (subMenus.size() > 0) {
+ menu = subMenus.get(subMenus.size() - 1);
+ }
+ mouse.setX(mouse.getX() - menu.getX());
+ mouse.setY(mouse.getY() - menu.getY());
+ }
+ menu.handleEvent(event);
+ return;
+ }
+
+ if (event instanceof TKeypressEvent) {
+ TKeypressEvent keypress = (TKeypressEvent) event;
+
+ // See if this key matches an accelerator, and if so dispatch the
+ // menu event.
+ TKeypress keypressLowercase = keypress.getKey().toLowerCase();
+ TMenuItem item = null;
+ synchronized (accelerators) {
+ item = accelerators.get(keypressLowercase);
+ }
+ if (item != null) {
+ // Let the menu item dispatch
+ item.dispatch();
+ return;
+ } else {
+ // Handle the keypress
+ if (onKeypress(keypress)) {
+ return;
+ }
+ }
+ }
+
+ if (event instanceof TCommandEvent) {
+ if (onCommand((TCommandEvent) event)) {
+ return;
+ }
+ }
+
+ if (event instanceof TMenuEvent) {
+ if (onMenu((TMenuEvent) event)) {
+ return;
+ }
+ }
+
+ // Dispatch events to the active window -------------------------------
+ for (TWindow window: windows) {
+ if (window.getActive()) {
+ if (event instanceof TMouseEvent) {
+ TMouseEvent mouse = (TMouseEvent) event;
+ // Convert the mouse relative x/y to window coordinates
+ assert (mouse.getX() == mouse.getAbsoluteX());
+ assert (mouse.getY() == mouse.getAbsoluteY());
+ mouse.setX(mouse.getX() - window.getX());
+ mouse.setY(mouse.getY() - window.getY());
+ }
+ // System.err("TApplication dispatch event: %s\n", event);
+ window.handleEvent(event);
+ break;
+ }
+ }
+ }
+ /**
+ * Dispatch one event to the appropriate widget or application-level
+ * event handler. This is the secondary event handler used by certain
+ * special dialogs (currently TMessageBox and TFileOpenBox).
+ *
+ * @param event the input event to consume
+ * @see #primaryHandleEvent(TInputEvent event)
+ */
+ private void secondaryHandleEvent(final TInputEvent event) {
+ secondaryEventReceiver.handleEvent(event);
+ }
+
+ /**
+ * Enable a widget to override the primary event thread.
+ *
+ * @param widget widget that will receive events
+ */
+ public final void enableSecondaryEventReceiver(final TWidget widget) {
+ assert (secondaryEventReceiver == null);
+ assert (secondaryEventHandler == null);
+ assert (widget instanceof TMessageBox);
+ secondaryEventReceiver = widget;
+ secondaryEventHandler = new WidgetEventHandler(this, false);
+ (new Thread(secondaryEventHandler)).start();
+
+ // Refresh
+ repaint = true;
+ }
+
+ /**
+ * Yield to the secondary thread.
+ */
+ public final void yield() {
+ assert (secondaryEventReceiver != null);
+ // This is where we handoff the event handler lock from the primary
+ // to secondary thread. We unlock here, and in a future loop the
+ // secondary thread locks again. When it gives up, we have the
+ // single lock back.
+ boolean oldLock = unlockHandleEvent();
+ assert (oldLock == true);
+
+ while (secondaryEventReceiver != null) {
+ synchronized (this) {
+ try {
+ this.wait();
+ } catch (InterruptedException e) {
+ // SQUASH
+ }
+ }
+ }
+ }
+
+ /**
+ * Do stuff when there is no user input.