fix(island): say why a drop is refused

A drop offering no local file:// URL was refused silently: the bubble
vanished and nothing happened. Measured on the first report: the file
manager offers a trashed file as trash:, with no path to read. The bubble
now shows the reason for a moment, Trash named as such, and the refusal is
logged with the URL schemes and offered formats (never the paths).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

2 files changed, 24 insertions, 6 deletions

diff --git a/desktop/island/Island.qml b/desktop/island/Island.qml
index 412cc58..5efe9bf 100644
--- a/desktop/island/Island.qml
+++ b/desktop/island/Island.qml
@@ -197,6 +197,9 @@ PanelWindow {
     // enters an input region, so the receptor is the sliver's width at rest
     // and grows to hold the bubble while a drag is over it.
     property bool dropHold: false
+    // Why the last drop was refused, shown in the bubble for a moment.
+    property string dropNote: ""
+    Timer { id: noteTimer; interval: 2500; onTriggered: win.dropNote = "" }
 
     Item {
         id: receptor
@@ -218,25 +221,38 @@ PanelWindow {
             onDropped: drop => {
                 win.dropHold = false;
                 const paths = drop.urls.map(u => Files.fromUrl(u)).filter(p => p !== "");
-                if (!paths.length) { drop.accepted = false; return; }
+                if (!paths.length) {
+                    // Said, not silent: a source offering no local file://
+                    // URL looked like a drop that did nothing. The file
+                    // manager offers a trashed file as trash:, which has no
+                    // path to read.
+                    const schemes = drop.urls.map(u => String(u).split(":")[0]);
+                    console.warn(`island: drop refused, no local file in ${drop.urls.length} URL(s): `
+                                 + schemes.join(", ") + ` formats: ${drop.formats.join(", ")}`);
+                    win.dropNote = schemes.includes("trash") ? "That is in the Trash: restore it first"
+                                                             : "Not a local file";
+                    noteTimer.restart();
+                    drop.accepted = false;
+                    return;
+                }
                 win.asst.attach(paths);
                 drop.accept(Qt.CopyAction);
             }
         }
 
         Rectangle {
-            visible: win.dropHold
+            visible: win.dropHold || win.dropNote !== ""
             anchors { horizontalCenter: parent.horizontalCenter; top: parent.top; topMargin: 14 }
             width: parent.width
             height: 72
             radius: 16
             color: Qt.alpha(Theme.base, 0.9)
             border.width: 1
-            border.color: Qt.alpha(Theme.accent, 0.6)
+            border.color: Qt.alpha(win.dropHold ? Theme.accent : Theme.red, 0.6)
             Text {
                 anchors.centerIn: parent
-                text: "Drop for the assistant"
-                color: Theme.text
+                text: win.dropHold ? "Drop for the assistant" : win.dropNote
+                color: win.dropHold ? Theme.text : Theme.red
                 font { family: Theme.fontFamily; pixelSize: Theme.fontSize - 2 }
             }
         }
diff --git a/desktop/island/README.md b/desktop/island/README.md
index 3387e2b..07c88cf 100644
--- a/desktop/island/README.md
+++ b/desktop/island/README.md
@@ -139,4 +139,6 @@ dropping on it hands the file to the assistant canvas, which opens in its
 file state with a new conversation. Wayland reports a drag only once it
 enters one of the surface's input regions, so the receptor is the sliver's
 width at rest and grows to hold the bubble while a drag is over it. Only
-`file://` URLs are taken.
+`file://` URLs are taken; a refused drop says why in the bubble for a
+moment. The file manager offers a trashed file as a `trash:` URL, which has
+no path to read: restore it first.