allow scrolling topic left and right v1 PROPOSED

aoife cassidy: 1
 allow scrolling topic left and right

 3 files changed, 33 insertions(+), 4 deletions(-)

[PATCH v1] allow scrolling topic left and right Export this patch

---
haven't managed to make clickable links work while scrolling too far,
would appreciate guidance on what would be the right course of action.

 app.go        |  6 ++++++
 ui/buffers.go | 13 ++++++++++---
 ui/ui.go      | 18 +++++++++++++++++-
 3 files changed, 33 insertions(+), 4 deletions(-)

diff --git a/app.go b/app.go
index b00c563..3e8cf40 100644
--- a/app.go
+++ b/app.go
@@ -603,6 +603,8 @@ func (app *App) handleMouseEvent(ev vaxis.Mouse) {
 				app.win.ScrollChannelUpBy(4)
 			} else if x > w-app.win.MemberWidth() {
 				app.win.ScrollMemberUpBy(4)
+			} else if y == 0 {
+				app.win.ScrollTopicLeftBy(4)
 			} else {
 				app.win.ScrollUpBy(4)
 			}
@@ -612,6 +614,8 @@ func (app *App) handleMouseEvent(ev vaxis.Mouse) {
 				app.win.ScrollChannelDownBy(4)
 			} else if x > w-app.win.MemberWidth() {
 				app.win.ScrollMemberDownBy(4)
+			} else if y == 0 {
+				app.win.ScrollTopicRightBy(4)
 			} else {
 				app.win.ScrollDownBy(4)
 			}
@@ -657,11 +661,13 @@ func (app *App) handleMouseEvent(ev vaxis.Mouse) {
 			if i := app.win.VerticalBufferOffset(y); i == app.win.ClickedBuffer() {
 				app.win.GoToBufferNo(i)
 				app.clearBufferCommand()
+				app.win.ResetTopicOffset()
 			}
 		} else if app.win.ChannelWidth() == 0 && y == h-1 {
 			if i := app.win.HorizontalBufferOffset(x); i >= 0 && i == app.win.ClickedBuffer() {
 				app.win.GoToBufferNo(i)
 				app.clearBufferCommand()
+				app.win.ResetTopicOffset()
 			}
 		} else if x > w-app.win.MemberWidth() {
 			if i := y - 2 + app.win.MemberOffset(); i >= 0 && i == app.win.ClickedMember() {
diff --git a/ui/buffers.go b/ui/buffers.go
index cb21267..e34a98e 100644
--- a/ui/buffers.go
+++ b/ui/buffers.go
@@ -962,7 +962,7 @@ func (bs *BufferList) DrawHorizontalBufferList(vx *Vaxis, x0, y0, width int, off
 	}
 }
 
-func (bs *BufferList) DrawTimeline(ui *UI, x0, y0, nickColWidth int) {
+func (bs *BufferList) DrawTimeline(ui *UI, x0, y0, nickColWidth int, topicOffset *int) {
 	vx := ui.vx
 	clearArea(vx, x0, y0, bs.tlInnerWidth+nickColWidth+9, bs.tlHeight+2)
 
@@ -974,6 +974,13 @@ func (bs *BufferList) DrawTimeline(ui *UI, x0, y0, nickColWidth int) {
 		}
 	}
 
+	if x0+len(b.topic.string)-*topicOffset < bs.tlInnerWidth+nickColWidth {
+		*topicOffset = x0 + len(b.topic.string) - (bs.tlInnerWidth + nickColWidth)
+		if *topicOffset < 0 {
+			*topicOffset = 0
+		}
+	}
+
 	xTopic := x0
 	{
 		// TODO: factorize this (same code for drawing timeline)
@@ -981,8 +988,8 @@ func (bs *BufferList) DrawTimeline(ui *UI, x0, y0, nickColWidth int) {
 		var st vaxis.Style
 		nextStyles := b.topic.styles
 
-		i := 0
-		sr := []rune(b.topic.string)
+		i := *topicOffset
+		sr := []rune(b.topic.string[*topicOffset:])
 		for len(sr) > 0 {
 			if 0 < len(nextStyles) && nextStyles[0].Start == i {
 				st = nextStyles[0].Style
diff --git a/ui/ui.go b/ui/ui.go
index f4e788a..8dddfc4 100644
--- a/ui/ui.go
+++ b/ui/ui.go
@@ -63,6 +63,7 @@ type UI struct {
 	channelOffset int
 	memberClicked int
 	memberOffset  int
+	topicOffset   int
 
 	channelWidth int
 	memberWidth  int
@@ -350,6 +351,21 @@ func (ui *UI) ScrollMemberDownBy(n int) {
 	ui.memberOffset += n
 }
 
+func (ui *UI) ScrollTopicLeftBy(n int) {
+	ui.topicOffset -= n
+	if ui.topicOffset < 0 {
+		ui.topicOffset = 0
+	}
+}
+
+func (ui *UI) ScrollTopicRightBy(n int) {
+	ui.topicOffset += n
+}
+
+func (ui *UI) ResetTopicOffset() {
+	ui.topicOffset = 0
+}
+
 func (ui *UI) LinesAboveOffset() int {
 	return ui.bs.LinesAboveOffset()
 }
@@ -650,7 +666,7 @@ func (ui *UI) Draw(members []irc.Member) {
 
 	w, h := ui.vx.window.Size()
 
-	ui.bs.DrawTimeline(ui, ui.channelWidth, 0, ui.config.NickColWidth)
+	ui.bs.DrawTimeline(ui, ui.channelWidth, 0, ui.config.NickColWidth, &ui.topicOffset)
 	if ui.channelWidth == 0 {
 		ui.bs.DrawHorizontalBufferList(ui.vx, 0, h-1, w-ui.memberWidth, &ui.channelOffset)
 	} else {

base-commit: b24c37f5ca93337da7255556cabf85ba10ef347f
-- 
2.45.2