activation+focuschain: Fixed activation not handling per-output VDs

src/activation.cpp

@@ -493,6 +493,7 @@ bool Workspace::activateNextWindow(Window *window)
 
     VirtualDesktop *desktop = VirtualDesktopManager::self()->currentDesktop();
 
+    // TODO: !focusCandidate will always be true?
     if (!focusCandidate && showingDesktop()) {
         focusCandidate = findDesktop(true, desktop); // to not break the state
     }
@@ -516,7 +517,13 @@ bool Workspace::activateNextWindow(Window *window)
         }
         if (!focusCandidate) {
             // nope, ask the focus chain for the next candidate
-            focusCandidate = m_focusChain->nextForDesktop(window, desktop);
+            //            focusCandidate = m_focusChain->nextForDesktop(window, desktop);
+
+            // Not using desktop-specific focus chains, there is
+            // probably an optimisation reason to use those. Or a
+            // logic reason. If something breaks, this is probably
+            // why!
+            focusCandidate = m_focusChain->nextUsableMostRecentlyUsed(window);
         }
     }
 

src/focuschain.cpp

@@ -252,11 +252,13 @@ Window *FocusChain::nextMostRecentlyUsed(Window *reference) const
 // copied from activation.cpp
 bool FocusChain::isUsableFocusCandidate(Window *c, Window *prev) const
 {
-    return c != prev && !c->isShade() && c->isShown() && c->isOnCurrentDesktop() && c->isOnCurrentActivity() && (!m_separateScreenFocus || c->isOnOutput(prev ? prev->output() : workspace()->activeOutput()));
+    // TODO: Figure out why separate screen focus doesn't work.
+    return c != prev && !c->isShade() && c->isShown() && c->isOnCurrentDesktop() && c->isOnCurrentActivity(); // && (!m_separateScreenFocus || c->isOnOutput(prev ? prev->output() : workspace()->activeOutput()));
 }
 
 Window *FocusChain::nextForDesktop(Window *reference, VirtualDesktop *desktop) const
 {
+    qInfo("nextForDesktop");
     auto it = m_desktopFocusChains.constFind(desktop);
     if (it == m_desktopFocusChains.constEnd()) {
         return nullptr;
@@ -271,6 +273,37 @@ Window *FocusChain::nextForDesktop(Window *reference, VirtualDesktop *desktop) c
     return nullptr;
 }
 
+// TODO: Check that the logic actually makes sense.
+Window *FocusChain::nextUsableMostRecentlyUsed(Window *reference) const
+{
+    if (m_mostRecentlyUsed.isEmpty()) {
+        return nullptr;
+    }
+    const int index = m_mostRecentlyUsed.indexOf(reference);
+    if (index == -1) {
+        auto first = m_mostRecentlyUsed.first();
+        if (isUsableFocusCandidate(first, reference)) {
+            return first;
+        }
+        return nullptr;
+    }
+    if (index == 0) {
+        auto last = m_mostRecentlyUsed.last();
+        if (isUsableFocusCandidate(last, reference)) {
+            return last;
+        }
+        return nullptr;
+    }
+    for (int i = index - 1; i >= 0; --i) {
+        auto window = m_mostRecentlyUsed.at(i);
+        if (isUsableFocusCandidate(window, reference)) {
+            return window;
+        }
+    }
+    qInfo("NULL");
+    return nullptr;
+}
+
 void FocusChain::makeFirstInChain(Window *window, Chain &chain)
 {
     if (window->isDeleted()) {

src/focuschain.h

@@ -164,6 +164,8 @@ public:
      */
     Window *firstMostRecentlyUsed() const;
 
+    Window *nextUsableMostRecentlyUsed(Window *reference) const;
+
     bool isUsableFocusCandidate(Window *window, Window *prev) const;
 
 public Q_SLOTS: