Added MarkdownRenderer.

helper_test.go

@@ -5,8 +5,9 @@
 package termui
 
 import (
-	"fmt"
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestStr2Rune(t *testing.T) {
@@ -54,20 +55,11 @@ func TestTrim(t *testing.T) {
 	}
 }
 
-func assertEqual(t *testing.T, expected, got interface{}, msg ...interface{}) {
-	baseMsg := fmt.Sprintf("Got %v expected %v", got, expected)
-	msg = append([]interface{}{baseMsg}, msg...)
-
-	if expected != got {
-		t.Error(fmt.Sprint(msg...))
-	}
-}
-
 func TestTrimStrIfAppropriate_NoTrim(t *testing.T) {
-	assertEqual(t, "hello", TrimStrIfAppropriate("hello", 5))
+	assert.Equal(t, "hello", TrimStrIfAppropriate("hello", 5))
 }
 
 func TestTrimStrIfAppropriate(t *testing.T) {
-	assertEqual(t, "hel…", TrimStrIfAppropriate("hello", 4))
-	assertEqual(t, "h…", TrimStrIfAppropriate("hello", 2))
+	assert.Equal(t, "hel…", TrimStrIfAppropriate("hello", 4))
+	assert.Equal(t, "h…", TrimStrIfAppropriate("hello", 2))
 }

list.go

@@ -83,14 +83,13 @@ func (l *List) Buffer() []Point {
 		}
 		for i, v := range trimItems {
 			rs := trimStr2Runes(v, l.innerWidth)
-
 			j := 0
+
 			for _, vv := range rs {
 				w := charWidth(vv)
 				p := Point{}
 				p.X = l.innerX + j
 				p.Y = l.innerY + i
-
 				p.Ch = vv
 				p.Bg = l.ItemBgColor
 				p.Fg = l.ItemFgColor

textRender.go

@@ -0,0 +1,82 @@
+package termui
+
+import (
+	"regexp"
+	"strings"
+)
+
+// TextRender adds common methods for rendering a text on screeen.
+type TextRender interface {
+	NormalizedText(text string) string
+	RenderSequence(text string, lastColor, background Attribute) RenderedSubsequence
+}
+
+type subSecequence struct {
+	start int
+	end   int
+	color Attribute
+}
+
+// MarkdownRegex is used by MarkdownTextRenderer to determine how to format the
+// text.
+const MarkdownRegex = `(?:\[([[a-z]+)\])\(([a-z\s,]+)\)`
+
+// unexported because a pattern can't be a constant and we don't want anyone
+// messing with the regex.
+var markdownPattern = regexp.MustCompile(MarkdownRegex)
+
+// MarkdownTextRenderer is used for rendering the text with colors using
+// markdown-like syntax.
+// See: https://github.com/gizak/termui/issues/4#issuecomment-87270635
+type MarkdownTextRenderer struct{}
+
+// NormalizedText returns the text the user will see (without colors).
+// It strips out all formatting option and only preserves plain text.
+func (r MarkdownTextRenderer) NormalizedText(text string) string {
+	lText := strings.ToLower(text)
+	indexes := markdownPattern.FindAllStringSubmatchIndex(lText, -1)
+
+	// Interate through indexes in reverse order.
+	for i := len(indexes) - 1; i >= 0; i-- {
+		theIndex := indexes[i]
+		start, end := theIndex[0], theIndex[1]
+		contentStart, contentEnd := theIndex[2], theIndex[3]
+
+		text = text[:start] + text[contentStart:contentEnd] + text[end:]
+	}
+
+	return text
+}
+
+// RenderedSubsequence is a string sequence that is capable of returning the
+// Buffer used by termui for displaying the colorful string.
+type RenderedSubsequence struct {
+	RawText         string
+	NormalizedText  string
+	LastColor       Attribute
+	BackgroundColor Attribute
+
+	sequences subSecequence
+}
+
+// Buffer returns the colorful formatted buffer and the last color that was
+// used.
+func (s *RenderedSubsequence) Buffer(x, y int) ([]Point, Attribute) {
+	// var buffer []Point
+	// dx := 0
+	// for _, r := range []rune(s.NormalizedText) {
+	// 	p := Point{
+	// 		Ch: r,
+	// 		X:  x + dx,
+	// 		Y:  y,
+	// 		Fg: Attribute(rand.Intn(8)),
+	// 		Bg: background,
+	// 	}
+	//
+	// 	buffer = append(buffer, p)
+	// 	dx += charWidth(r)
+	// }
+	//
+	// return buffer
+	return nil, s.LastColor
+}

textRender_test.go

@@ -0,0 +1,20 @@
+package termui
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestMarkdownTextRenderer_NormalizedText(t *testing.T) {
+	renderer := MarkdownTextRenderer{}
+
+	got := renderer.NormalizedText("[ERROR](red,bold) Something went wrong")
+	assert.Equal(t, got, "ERROR Something went wrong")
+
+	got = renderer.NormalizedText("[foo](g) hello [bar](green) world")
+	assert.Equal(t, got, "foo hello bar world")
+
+	got = renderer.NormalizedText("[foo](g) hello [bar]green (world)")
+	assert.Equal(t, got, "foo hello [bar]green (world)")
+}