IDEA-319836 Don't update tool window weights if editor area isn't there

Sometimes, apparently when the IDE is being initialized, some tool windows
appear before the editor area (EditorSplitters technically) is created and visible.
When that happens, ThreeComponentSplitter uses that area to extend the tool
window beyond its weight. In the worst case the Project View takes all available
space. Once its weight is updated based on its new size, it just stays like that
forever.

To fix that, we check that the middle component is present and visible. If it's not,
we don't update weights and write a log message. While this doesn't fix the original
issue, it prevents the new weight from sticking and the Project View taking all space
until manually resized.

While we're at it, add some useful logging when weights are updated or not updated.

GitOrigin-RevId: 7e03dc699b569940db1706c69f474c1f5df4caf2

platform/platform-impl/src/com/intellij/openapi/wm/impl/ToolWindowManagerImpl.kt

@@ -46,6 +46,7 @@ import com.intellij.openapi.project.ex.ProjectEx
 import com.intellij.openapi.project.processOpenedProjects
 import com.intellij.openapi.ui.FrameWrapper
 import com.intellij.openapi.ui.Splitter
+import com.intellij.openapi.ui.ThreeComponentsSplitter
 import com.intellij.openapi.ui.popup.Balloon
 import com.intellij.openapi.ui.popup.JBPopupFactory
 import com.intellij.openapi.util.*
@@ -600,6 +601,7 @@ open class ToolWindowManagerImpl @NonInjectable @TestOnly internal constructor(
 
     if (isUnifiedToolWindowSizesEnabled()) {
       info.weight = layoutState.getUnifiedAnchorWeight(info.anchor)
+      LOG.debug("Activated tool window: ${info.id}, using ${info.anchor} unified weight of ${info.weight}")
     }
 
     if (source != null) {
@@ -1313,9 +1315,11 @@ open class ToolWindowManagerImpl @NonInjectable @TestOnly internal constructor(
           if (another != null && anchor.isUltrawideLayout()) { // split windows side-by-side, set weight of the entire splitter
             weight += another.new.weight
           }
+          LOG.debug("Setting ${item.entry.id} weight=${weight} from the saved layout")
           toolWindowPane.setWeight(anchor, weight)
         }
         if (item.old.sideWeight != item.new.sideWeight) {
+          LOG.debug("Setting ${item.entry.id} side weight ${item.new.sideWeight} from the saved layout")
           toolWindowPane.setSideWeight(item.entry.toolWindow, item.new.sideWeight)
         }
       }
@@ -2033,8 +2037,11 @@ open class ToolWindowManagerImpl @NonInjectable @TestOnly internal constructor(
     }
     else {
       // docked and sliding windows
+      val dockingAreaComponent = if (source.parent is Splitter) source.parent as Splitter else source
+      if (!dockingAreaIsInSplitterWithVisibleEditorArea(dockingAreaComponent)) {
+        return
+      }
       val anchor = info.anchor
-      val dockingAreaComponent: Component
       if (source.parent is Splitter) {
         var sizeInSplit = if (anchor.isSplitVertically) source.height else source.width
         val splitter = source.parent as Splitter
@@ -2044,20 +2051,37 @@ open class ToolWindowManagerImpl @NonInjectable @TestOnly internal constructor(
         info.sideWeight = getAdjustedRatio(partSize = sizeInSplit,
                                            totalSize = if (anchor.isSplitVertically) splitter.height else splitter.width,
                                            direction = if (splitter.secondComponent === source) -1 else 1)
-        dockingAreaComponent = splitter
-      }
-      else {
-        dockingAreaComponent = source
       }
       val toolWindowPane = getToolWindowPane(toolWindow)
       val toolWindowWeight = getAdjustedWeight(toolWindowPane, anchor, source)
       val dockingAreaWeight = getAdjustedWeight(toolWindowPane, anchor, dockingAreaComponent)
       info.weight = toolWindowWeight
       layoutState.setUnifiedAnchorWeight(anchor, dockingAreaWeight)
+      LOG.debug("Moved/resized tool window ${info.id}, updated weight=${toolWindowWeight}, docking area weight=${dockingAreaWeight}")
     }
     fireStateChanged(MovedOrResized, toolWindow)
   }
 
+  private fun dockingAreaIsInSplitterWithVisibleEditorArea(dockingAreaComponent: Component): Boolean {
+    val parentSplitter = dockingAreaComponent.parent as? ThreeComponentsSplitter
+    if (parentSplitter == null) {
+      LOG.warn(Exception("InternalDecoratorImpl/Splitter is not in a ThreeComponentsSplitter, " +
+                         "can't perform sanity checks, tool window info is not updated. " +
+                         "Actual parent = ${dockingAreaComponent.parent}"))
+      return false
+    }
+    val editorComponent = parentSplitter.innerComponent
+    if (editorComponent == null) {
+      LOG.info("Editor area is null, not updating tool window weights")
+      return false
+    }
+    if (!editorComponent.isVisible) {
+      LOG.info("Editor area is not visible, not updating tool window weights")
+      return false
+    }
+    return true
+  }
+
   private fun getAdjustedWeight(
     toolWindowPane: ToolWindowPane,
     anchor: ToolWindowAnchor,