Print --wrap-sign in preview window

Close #4233

3 files changed, 63 insertions, 32 deletions

diff --git a/src/tui/light.go b/src/tui/light.go
index ab7bd87f..bf2a2fd2 100644
--- a/src/tui/light.go
+++ b/src/tui/light.go
@@ -44,8 +44,9 @@ func (r *LightRenderer) stderr(str string) {
 	r.stderrInternal(str, true, "")
 }
 
-const CR string = "\x1b[2m␍"
-const LF string = "\x1b[2m␊"
+const DIM string = "\x1b[2m"
+const CR string = DIM + "␍"
+const LF string = DIM + "␊"
 
 func (r *LightRenderer) stderrInternal(str string, allowNLCR bool, resetCode string) {
 	bytes := []byte(str)
@@ -127,19 +128,21 @@ type LightRenderer struct {
 }
 
 type LightWindow struct {
-	renderer   *LightRenderer
-	colored    bool
-	windowType WindowType
-	border     BorderStyle
-	top        int
-	left       int
-	width      int
-	height     int
-	posx       int
-	posy       int
-	tabstop    int
-	fg         Color
-	bg         Color
+	renderer      *LightRenderer
+	colored       bool
+	windowType    WindowType
+	border        BorderStyle
+	top           int
+	left          int
+	width         int
+	height        int
+	posx          int
+	posy          int
+	tabstop       int
+	fg            Color
+	bg            Color
+	wrapSign      string
+	wrapSignWidth int
 }
 
 func NewLightRenderer(ttyin *os.File, theme *ColorTheme, forceBlack bool, mouse bool, tabstop int, clearOnExit bool, fullscreen bool, maxHeightFunc func(int) int) (Renderer, error) {
@@ -1105,11 +1108,12 @@ type wrappedLine struct {
 	displayWidth int
 }
 
-func wrapLine(input string, prefixLength int, max int, tabstop int) []wrappedLine {
+func wrapLine(input string, prefixLength int, initialMax int, tabstop int, wrapSignWidth int) []wrappedLine {
 	lines := []wrappedLine{}
 	width := 0
 	line := ""
 	gr := uniseg.NewGraphemes(input)
+	max := initialMax
 	for gr.Next() {
 		rs := gr.Runes()
 		str := string(rs)
@@ -1131,6 +1135,7 @@ func wrapLine(input string, prefixLength int, max int, tabstop int) []wrappedLin
 			line = str
 			prefixLength = 0
 			width = w
+			max = initialMax - wrapSignWidth
 		}
 	}
 	lines = append(lines, wrappedLine{string(line), width})
@@ -1140,7 +1145,7 @@ func wrapLine(input string, prefixLength int, max int, tabstop int) []wrappedLin
 func (w *LightWindow) fill(str string, resetCode string) FillReturn {
 	allLines := strings.Split(str, "\n")
 	for i, line := range allLines {
-		lines := wrapLine(line, w.posx, w.width, w.tabstop)
+		lines := wrapLine(line, w.posx, w.width, w.tabstop, w.wrapSignWidth)
 		for j, wl := range lines {
 			w.stderrInternal(wl.text, false, resetCode)
 			w.posx += wl.displayWidth
@@ -1153,6 +1158,11 @@ func (w *LightWindow) fill(str string, resetCode string) FillReturn {
 				w.MoveAndClear(w.posy, w.posx)
 				w.Move(w.posy+1, 0)
 				w.renderer.stderr(resetCode)
+				if len(lines) > 1 {
+					w.stderrInternal(DIM+w.wrapSign, false, resetCode)
+					w.renderer.stderr(resetCode)
+					w.Move(w.posy, w.wrapSignWidth)
+				}
 			}
 		}
 	}
@@ -1226,6 +1236,11 @@ func (w *LightWindow) EraseMaybe() bool {
 	return false
 }
 
+func (w *LightWindow) SetWrapSign(sign string, width int) {
+	w.wrapSign = sign
+	w.wrapSignWidth = width
+}
+
 func (r *LightRenderer) HideCursor() {
 	r.showCursor = false
 	r.csi("?25l")
diff --git a/src/tui/tcell.go b/src/tui/tcell.go
index 0009b912..b70eed48 100644
--- a/src/tui/tcell.go
+++ b/src/tui/tcell.go
@@ -39,20 +39,22 @@ func (p ColorPair) style() tcell.Style {
 type Attr int32
 
 type TcellWindow struct {
-	color       bool
-	windowType  WindowType
-	top         int
-	left        int
-	width       int
-	height      int
-	normal      ColorPair
-	lastX       int
-	lastY       int
-	moveCursor  bool
-	borderStyle BorderStyle
-	uri         *string
-	params      *string
-	showCursor  bool
+	color         bool
+	windowType    WindowType
+	top           int
+	left          int
+	width         int
+	height        int
+	normal        ColorPair
+	lastX         int
+	lastY         int
+	moveCursor    bool
+	borderStyle   BorderStyle
+	uri           *string
+	params        *string
+	showCursor    bool
+	wrapSign      string
+	wrapSignWidth int
 }
 
 func (w *TcellWindow) Top() int {
@@ -629,6 +631,11 @@ func (w *TcellWindow) EraseMaybe() bool {
 	return true
 }
 
+func (w *TcellWindow) SetWrapSign(sign string, width int) {
+	w.wrapSign = sign
+	w.wrapSignWidth = width
+}
+
 func (w *TcellWindow) EncloseX(x int) bool {
 	return x >= w.left && x < (w.left+w.width)
 }
@@ -757,11 +764,18 @@ Loop:
 
 		// word wrap:
 		xPos := w.left + w.lastX + lx
-		if xPos >= (w.left + w.width) {
+		if xPos >= w.left+w.width {
 			w.lastY++
 			w.lastX = 0
 			lx = 0
 			xPos = w.left
+			wgr := uniseg.NewGraphemes(w.wrapSign)
+			for wgr.Next() {
+				rs := wgr.Runes()
+				_screen.SetContent(w.left+lx, w.top+w.lastY, rs[0], rs[1:], style.Dim(true))
+				lx += uniseg.StringWidth(string(rs))
+			}
+			xPos = w.left + lx
 		}
 
 		yPos := w.top + w.lastY
diff --git a/src/tui/tui.go b/src/tui/tui.go
index 265d3cff..4f2fe2c6 100644
--- a/src/tui/tui.go
+++ b/src/tui/tui.go
@@ -659,6 +659,8 @@ type Window interface {
 	LinkEnd()
 	Erase()
 	EraseMaybe() bool
+
+	SetWrapSign(string, int)
 }
 
 type FullscreenRenderer struct {