Allow dragging of the preview window

src/terminal.go

@@ -2588,7 +2588,9 @@ func (t *Terminal) Loop() {
 			t.eventChan <- t.tui.GetChar()
 		}
 	}()
-	dragging := false
+	previewDraggingPos := -1
+	barDragging := false
+	wasDown := false
 	for looping {
 		var newCommand *string
 		var reloadSync bool
@@ -3032,8 +3034,15 @@ func (t *Terminal) Loop() {
 			case actMouse:
 				me := event.MouseEvent
 				mx, my := me.X, me.Y
+				clicked := !wasDown && me.Down
+				wasDown = me.Down
+				if !me.Down {
+					barDragging = false
+					previewDraggingPos = -1
+				}
+
+				// Scrolling
 				if me.S != 0 {
-					// Scroll
 					if t.window.Enclose(my, mx) && t.merger.Length() > 0 {
 						if t.multi > 0 && me.Mod {
 							toggle()
@@ -3043,7 +3052,24 @@ func (t *Terminal) Loop() {
 					} else if t.hasPreviewWindow() && t.pwindow.Enclose(my, mx) {
 						scrollPreviewBy(-me.S)
 					}
-				} else if t.window.Enclose(my, mx) {
+					break
+				}
+
+				// Preview dragging
+				if me.Down && (previewDraggingPos > 0 || clicked && t.hasPreviewWindow() && t.pwindow.Enclose(my, mx)) {
+					if previewDraggingPos > 0 {
+						scrollPreviewBy(previewDraggingPos - my)
+					}
+					previewDraggingPos = my
+					break
+				}
+
+				// Ignored
+				if !t.window.Enclose(my, mx) && !barDragging {
+					break
+				}
+
+				// Translate coordinates
 				mx -= t.window.Left()
 				my -= t.window.Top()
 				min := 2 + len(t.header)
@@ -3061,15 +3087,10 @@ func (t *Terminal) Loop() {
 						my = h - my - 1
 					}
 				}
-					dragging = me.Down && (dragging || my >= min && mx == t.window.Width()-1)
-					if me.Double {
-						// Double-click
-						if my >= min {
-							if t.vset(t.offset+my-min) && t.cy < t.merger.Length() {
-								return doActions(actionsFor(tui.DoubleClick))
-							}
-						}
-					} else if dragging && my >= min {
+
+				// Scrollbar dragging
+				barDragging = me.Down && (barDragging || clicked && my >= min && mx == t.window.Width()-1)
+				if barDragging {
 					barLength, barStart := t.getScrollbar()
 					if barLength > 0 {
 						maxItems := t.maxItems()
@@ -3082,7 +3103,21 @@ func (t *Terminal) Loop() {
 							req(reqList)
 						}
 					}
-					} else if me.Down {
+					break
+				}
+
+				// Double-click on an item
+				if me.Double && mx < t.window.Width()-1 {
+					// Double-click
+					if my >= min {
+						if t.vset(t.offset+my-min) && t.cy < t.merger.Length() {
+							return doActions(actionsFor(tui.DoubleClick))
+						}
+					}
+					break
+				}
+
+				if me.Down {
 					mx = util.Constrain(mx-t.promptLen, 0, len(t.input))
 					if my == t.promptLine() && mx >= 0 {
 						// Prompt
@@ -3099,7 +3134,6 @@ func (t *Terminal) Loop() {
 						return doActions(actionsFor(tui.RightClick))
 					}
 				}
-				}
 			case actReload, actReloadSync:
 				t.failed = nil