Properly handle mouse in read-only mode

Summary:
* Do not send mouse events and emulated up/down keys to programs when
   read-only mode is enabled.
* Set the currentTerminalDisplay before sending key events, like in
   keyPressEvent.
* wheelEvent code is restructured a bit to easily separate code not
   allowed in read-only mode.

Test Plan:
* Start Konsole
* Run `man man`, do not press any key after enter
* Turn on read only mode
* Try to scroll using mouse wheel.
* Expected result: scrolling does not work in read-only mode
* Actual result: scrolling works in read only mode (but only when no key
   has been pressed before on 2nd terminal screen)

* Start konsole
* Run a program which uses mouse events, e.g. `vim`
   (enable mouse with `:set mouse=a`)
* Make the program state suitable for using mouse events, e.g. enter a few
   lines of text
* Confirm that mouse events (clicks, selection, wheel) work in the program
* Turn on read-only mode
* Try:
  * Click (left/right/middle button), double click
  * Mouse wheel
  * Click and move (selecting)
* Expected result: mouse events are not passed to the program in read-only
   mode; nothing happens
* Actual result: mouse events are passed to the program

Reviewers: #konsole, hindenburg

Reviewed By: #konsole, hindenburg

Subscribers: hindenburg, #konsole

Tags: #konsole

Differential Revision: https://phabricator.kde.org/D11763

src/TerminalDisplay.cpp

@@ -2174,7 +2174,9 @@ void TerminalDisplay::mousePressEvent(QMouseEvent* ev)
                     _actSel = 1; // left mouse button pressed but nothing selected yet.
                 }
             } else {
-                emit mouseSignal(0, charColumn + 1, charLine + 1 + _scrollBar->value() - _scrollBar->maximum() , 0);
+                if(!_readOnly) {
+                    emit mouseSignal(0, charColumn + 1, charLine + 1 + _scrollBar->value() - _scrollBar->maximum() , 0);
+                }
             }
 
             if ((_openLinksByDirectClick || ((ev->modifiers() & Qt::ControlModifier) != 0u))) {
@@ -2192,7 +2194,9 @@ void TerminalDisplay::mousePressEvent(QMouseEvent* ev)
         if (_mouseMarks || ((ev->modifiers() & Qt::ShiftModifier) != 0u)) {
             emit configureRequest(ev->pos());
         } else {
-            emit mouseSignal(2, charColumn + 1, charLine + 1 + _scrollBar->value() - _scrollBar->maximum() , 0);
+            if(!_readOnly) {
+                emit mouseSignal(2, charColumn + 1, charLine + 1 + _scrollBar->value() - _scrollBar->maximum() , 0);
+            }
         }
     }
 }
@@ -2618,11 +2622,13 @@ void TerminalDisplay::processMidButtonClick(QMouseEvent* ev)
             Q_ASSERT(false);
         }
     } else {
-        int charLine = 0;
-        int charColumn = 0;
-        getCharacterPosition(ev->pos(), charLine, charColumn);
+        if(!_readOnly) {
+            int charLine = 0;
+            int charColumn = 0;
+            getCharacterPosition(ev->pos(), charLine, charColumn);
 
-        emit mouseSignal(1, charColumn + 1, charLine + 1 + _scrollBar->value() - _scrollBar->maximum() , 0);
+            emit mouseSignal(1, charColumn + 1, charLine + 1 + _scrollBar->value() - _scrollBar->maximum() , 0);
+        }
     }
 }
 
@@ -2650,11 +2656,13 @@ void TerminalDisplay::mouseDoubleClickEvent(QMouseEvent* ev)
 
     // pass on double click as two clicks.
     if (!_mouseMarks && !(ev->modifiers() & Qt::ShiftModifier)) {
-        // Send just _ONE_ click event, since the first click of the double click
-        // was already sent by the click handler
-        emit mouseSignal(0, charColumn + 1,
-                         charLine + 1 + _scrollBar->value() - _scrollBar->maximum(),
-                         0);  // left button
+        if(!_readOnly) {
+            // Send just _ONE_ click event, since the first click of the double click
+            // was already sent by the click handler
+            emit mouseSignal(0, charColumn + 1,
+                             charLine + 1 + _scrollBar->value() - _scrollBar->maximum(),
+                             0);  // left button
+        }
         return;
     }
 
@@ -2733,10 +2741,10 @@ void TerminalDisplay::wheelEvent(QWheelEvent* ev)
 
     const int modifiers = ev->modifiers();
 
-    _scrollWheelState.addWheelEvent(ev);
-
     // ctrl+<wheel> for zooming, like in konqueror and firefox
     if (((modifiers & Qt::ControlModifier) != 0u) && mouseWheelZoom()) {
+        _scrollWheelState.addWheelEvent(ev);
+
         int steps = _scrollWheelState.consumeLegacySteps(ScrollState::DEFAULT_ANGLE_SCROLL_LINE);
         for (;steps > 0; --steps) {
             // wheel-up for increasing font size
@@ -2746,21 +2754,22 @@ void TerminalDisplay::wheelEvent(QWheelEvent* ev)
             // wheel-down for decreasing font size
             decreaseFontSize();
         }
+    } else if (_mouseMarks && (_scrollBar->maximum() > 0)) {
+        // If the program running in the terminal is not interested in mouse events,
+        // send the event to the scrollbar if the slider has room to move
 
-        return;
-    }
+        _scrollWheelState.addWheelEvent(ev);
+
+        _scrollBar->event(ev);
+        _sessionController->setSearchStartToWindowCurrentLine();
+        _scrollWheelState.clearAll();
+    } else if (!_readOnly) {
+        _scrollWheelState.addWheelEvent(ev);
+
+        if(_mouseMarks && !_isPrimaryScreen) {
+            // Send simulated up / down key presses to the terminal program
+            // for the benefit of programs such as 'less' (which use the alternate screen)
 
-    // If the program running in the terminal is not interested in mouse events:
-    //  - Send the event to the scrollbar if the slider has room to move
-    //  - Otherwise, send simulated up / down key presses to the terminal program
-    //    for the benefit of programs such as 'less' (which use the alternate screen)
-    if (_mouseMarks) {
-        const bool canScroll = _scrollBar->maximum() > 0;
-        if (canScroll) {
-            _scrollBar->event(ev);
-            _sessionController->setSearchStartToWindowCurrentLine();
-            _scrollWheelState.clearAll();
-        } else if (!_isPrimaryScreen) {
             // assume that each Up / Down key event will cause the terminal application
             // to scroll by one line.
             //
@@ -2773,22 +2782,23 @@ void TerminalDisplay::wheelEvent(QWheelEvent* ev)
             QKeyEvent keyEvent(QEvent::KeyPress, keyCode, Qt::NoModifier);
 
             for (int i = 0; i < abs(lines); i++) {
+                _screenWindow->screen()->setCurrentTerminalDisplay(this);
                 emit keyPressedSignal(&keyEvent);
             }
-        }
-    } else {
-        // terminal program wants notification of mouse activity
-
-        int charLine;
-        int charColumn;
-        getCharacterPosition(ev->pos() , charLine , charColumn);
-        const int steps = _scrollWheelState.consumeLegacySteps(ScrollState::DEFAULT_ANGLE_SCROLL_LINE);
-        const int button = (steps > 0) ? 4 : 5;
-        for (int i = 0; i < abs(steps); ++i) {
-            emit mouseSignal(button,
-                             charColumn + 1,
-                             charLine + 1 + _scrollBar->value() - _scrollBar->maximum() ,
-                             0);
+        } else if (!_mouseMarks) {
+            // terminal program wants notification of mouse activity
+
+            int charLine;
+            int charColumn;
+            getCharacterPosition(ev->pos() , charLine , charColumn);
+            const int steps = _scrollWheelState.consumeLegacySteps(ScrollState::DEFAULT_ANGLE_SCROLL_LINE);
+            const int button = (steps > 0) ? 4 : 5;
+            for (int i = 0; i < abs(steps); ++i) {
+                emit mouseSignal(button,
+                                 charColumn + 1,
+                                 charLine + 1 + _scrollBar->value() - _scrollBar->maximum() ,
+                                 0);
+            }
         }
     }
 }