Add Mouseable

This adds the Mouseable interface. When this is implemented for a
component that item can accept and process mouseevents.

At the top level when a mouse event is received it is passed to the
grid's handler and then it trickles down until it reaches a component
that can actually handle it, such as the tablist, dirlist or msglist.

A mouse event is passed so that components can handle other things such
as scrolling with the mousewheel. The components themselves then perform
the necessary actions.

Clicking emails in the messagelist opens them in a new tab.

Textinputs can be clicked to position the cursor inside them.

Mouseevents are not forwarded to the terminal at the moment.

Elements which do not handle mouse events are not required to implement
the Mouseable interface.

1 files changed, 71 insertions, 1 deletions

diff --git a/widgets/msgviewer.go b/widgets/msgviewer.go
index e210616a..c1790707 100644
--- a/widgets/msgviewer.go
+++ b/widgets/msgviewer.go
@@ -42,6 +42,9 @@ type PartSwitcher struct {
 	selected       int
 	showHeaders    bool
 	alwaysShowMime bool
+
+	height int
+	mv     *MessageViewer
 }
 
 func NewMessageViewer(acct *AccountView, conf *config.AercConfig,
@@ -77,7 +80,7 @@ func NewMessageViewer(acct *AccountView, conf *config.AercConfig,
 	grid.AddChild(header).At(0, 0)
 	grid.AddChild(switcher).At(1, 0)
 
-	return &MessageViewer{
+	mv := &MessageViewer{
 		acct:     acct,
 		conf:     conf,
 		grid:     grid,
@@ -85,6 +88,9 @@ func NewMessageViewer(acct *AccountView, conf *config.AercConfig,
 		store:    store,
 		switcher: switcher,
 	}
+	switcher.mv = mv
+
+	return mv
 }
 
 func fmtHeader(msg *models.MessageInfo, header string) string {
@@ -194,6 +200,13 @@ func (mv *MessageViewer) Draw(ctx *ui.Context) {
 	mv.grid.Draw(ctx)
 }
 
+func (mv *MessageViewer) MouseEvent(localX int, localY int, event tcell.Event) {
+	if mv.err != nil {
+		return
+	}
+	mv.grid.MouseEvent(localX, localY, event)
+}
+
 func (mv *MessageViewer) Invalidate() {
 	mv.grid.Invalidate()
 }
@@ -295,6 +308,7 @@ func (ps *PartSwitcher) Draw(ctx *ui.Context) {
 		return
 	}
 	// TODO: cap height and add scrolling for messages with many parts
+	ps.height = ctx.Height()
 	y := ctx.Height() - height
 	for i, part := range ps.parts {
 		style := tcell.StyleDefault.Reverse(ps.selected == i)
@@ -311,6 +325,62 @@ func (ps *PartSwitcher) Draw(ctx *ui.Context) {
 		0, 0, ctx.Width(), ctx.Height()-height))
 }
 
+func (ps *PartSwitcher) MouseEvent(localX int, localY int, event tcell.Event) {
+	switch event := event.(type) {
+	case *tcell.EventMouse:
+		switch event.Buttons() {
+		case tcell.Button1:
+			height := len(ps.parts)
+			y := ps.height - height
+			if localY < y {
+				ps.parts[ps.selected].term.MouseEvent(localX, localY, event)
+			}
+			for i, _ := range ps.parts {
+				if localY != y+i {
+					continue
+				}
+				if ps.parts[i].part.MIMEType == "multipart" {
+					continue
+				}
+				if ps.parts[ps.selected].term != nil {
+					ps.parts[ps.selected].term.Focus(false)
+				}
+				ps.selected = i
+				ps.Invalidate()
+				if ps.parts[ps.selected].term != nil {
+					ps.parts[ps.selected].term.Focus(true)
+				}
+			}
+		case tcell.WheelDown:
+			height := len(ps.parts)
+			y := ps.height - height
+			if localY < y {
+				ps.parts[ps.selected].term.MouseEvent(localX, localY, event)
+			}
+			if ps.parts[ps.selected].term != nil {
+				ps.parts[ps.selected].term.Focus(false)
+			}
+			ps.mv.NextPart()
+			if ps.parts[ps.selected].term != nil {
+				ps.parts[ps.selected].term.Focus(true)
+			}
+		case tcell.WheelUp:
+			height := len(ps.parts)
+			y := ps.height - height
+			if localY < y {
+				ps.parts[ps.selected].term.MouseEvent(localX, localY, event)
+			}
+			if ps.parts[ps.selected].term != nil {
+				ps.parts[ps.selected].term.Focus(false)
+			}
+			ps.mv.PreviousPart()
+			if ps.parts[ps.selected].term != nil {
+				ps.parts[ps.selected].term.Focus(true)
+			}
+		}
+	}
+}
+
 func (mv *MessageViewer) Event(event tcell.Event) bool {
 	return mv.switcher.Event(event)
 }