From bbf3bb67979d99b22bc13690944b1ab56e7e8ac6 Mon Sep 17 00:00:00 2001
From: Anson Chan <anson0370@gmail.com>
Date: Fri, 22 Feb 2019 13:08:41 +0800
Subject: [PATCH] fix: #226, unicode strings display in paragraph, table and
 list

---
 buffer.go            |  9 +++++++--
 utils.go             | 19 ++++++++++++++++++-
 widgets/list.go      |  3 ++-
 widgets/paragraph.go |  3 ++-
 widgets/table.go     |  9 ++++++---
 5 files changed, 35 insertions(+), 8 deletions(-)

diff --git a/buffer.go b/buffer.go
index 2c33a1d..ac22934 100644
--- a/buffer.go
+++ b/buffer.go
@@ -6,6 +6,8 @@ package termui
 
 import (
 	"image"
+
+	rw "github.com/mattn/go-runewidth"
 )
 
 // Cell represents a viewable terminal cell
@@ -65,7 +67,10 @@ func (self *Buffer) Fill(c Cell, rect image.Rectangle) {
 }
 
 func (self *Buffer) SetString(s string, style Style, p image.Point) {
-	for i, char := range s {
-		self.SetCell(Cell{char, style}, image.Pt(p.X+i, p.Y))
+	runes := []rune(s)
+	x := 0
+	for _, char := range runes {
+		self.SetCell(Cell{char, style}, image.Pt(p.X+x, p.Y))
+		x += rw.RuneWidth(char)
 	}
 }
diff --git a/utils.go b/utils.go
index f780451..eea7b84 100644
--- a/utils.go
+++ b/utils.go
@@ -189,8 +189,9 @@ func CellsToString(cells []Cell) string {
 func TrimCells(cells []Cell, w int) []Cell {
 	s := CellsToString(cells)
 	s = TrimString(s, w)
+	runes := []rune(s)
 	newCells := []Cell{}
-	for i, r := range s {
+	for i, r := range runes {
 		newCells = append(newCells, Cell{r, cells[i].Style})
 	}
 	return newCells
@@ -212,3 +213,19 @@ func SplitCells(cells []Cell, r rune) [][]Cell {
 	}
 	return splitCells
 }
+
+type CellWithX struct {
+	X    int
+	Cell Cell
+}
+
+func BuildCellChannel(cells []Cell) chan CellWithX {
+	c := make(chan CellWithX, len(cells))
+	index := 0
+	for _, cell := range cells {
+		c <- CellWithX{X: index, Cell: cell}
+		index += rw.RuneWidth(cell.Rune)
+	}
+	close(c)
+	return c
+}
diff --git a/widgets/list.go b/widgets/list.go
index 4e6c463..0654de6 100644
--- a/widgets/list.go
+++ b/widgets/list.go
@@ -8,6 +8,7 @@ import (
 	"image"
 
 	. "github.com/gizak/termui"
+	rw "github.com/mattn/go-runewidth"
 )
 
 type List struct {
@@ -57,7 +58,7 @@ func (self *List) Draw(buf *Buffer) {
 					break
 				} else {
 					buf.SetCell(NewCell(cells[j].Rune, style), point)
-					point = point.Add(image.Pt(1, 0))
+					point = point.Add(image.Pt(rw.RuneWidth(cells[j].Rune), 0))
 				}
 			}
 		}
diff --git a/widgets/paragraph.go b/widgets/paragraph.go
index 9498f16..34ca187 100644
--- a/widgets/paragraph.go
+++ b/widgets/paragraph.go
@@ -40,7 +40,8 @@ func (self *Paragraph) Draw(buf *Buffer) {
 			break
 		}
 		row = TrimCells(row, self.Inner.Dx())
-		for x, cell := range row {
+		for signal := range BuildCellChannel(row) {
+			x, cell := signal.X, signal.Cell
 			buf.SetCell(cell, image.Pt(x, y).Add(self.Inner.Min))
 		}
 	}
diff --git a/widgets/table.go b/widgets/table.go
index 14f58ef..3660ff1 100644
--- a/widgets/table.go
+++ b/widgets/table.go
@@ -74,7 +74,8 @@ func (self *Table) Draw(buf *Buffer) {
 			col := ParseText(row[j], rowStyle)
 			// draw row cell
 			if len(col) > columnWidths[j] || self.TextAlign == AlignLeft {
-				for k, cell := range col {
+				for signal := range BuildCellChannel(col) {
+					k, cell := signal.X, signal.Cell
 					if k == columnWidths[j] || colXCoordinate+k == self.Inner.Max.X {
 						cell.Rune = ELLIPSES
 						buf.SetCell(cell, image.Pt(colXCoordinate+k-1, yCoordinate))
@@ -86,12 +87,14 @@ func (self *Table) Draw(buf *Buffer) {
 			} else if self.TextAlign == AlignCenter {
 				xCoordinateOffset := (columnWidths[j] - len(col)) / 2
 				stringXCoordinate := xCoordinateOffset + colXCoordinate
-				for k, cell := range col {
+				for signal := range BuildCellChannel(col) {
+					k, cell := signal.X, signal.Cell
 					buf.SetCell(cell, image.Pt(stringXCoordinate+k, yCoordinate))
 				}
 			} else if self.TextAlign == AlignRight {
 				stringXCoordinate := MinInt(colXCoordinate+columnWidths[j], self.Inner.Max.X) - len(col)
-				for k, cell := range col {
+				for signal := range BuildCellChannel(col) {
+					k, cell := signal.X, signal.Cell
 					buf.SetCell(cell, image.Pt(stringXCoordinate+k, yCoordinate))
 				}
 			}