1 files changed, 105 insertions, 0 deletions
diff --git a/pkg/cli/ui.go b/pkg/cli/ui.go
new file mode 100644
index 0000000..c4eff69
--- /dev/null
+++ b/pkg/cli/ui.go
@@ -0,0 +1,105 @@
+/*******************************************************************************
+*
+* Copyright 2017 Stefan Majewsky <majewsky@gmx.net>
+*
+* This program is free software: you can redistribute it and/or modify it under
+* the terms of the GNU General Public License as published by the Free Software
+* Foundation, either version 3 of the License, or (at your option) any later
+* version.
+*
+* This program is distributed in the hope that it will be useful, but WITHOUT ANY
+* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+* A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License along with
+* this program. If not, see <http://www.gnu.org/licenses/>.
+*
+*******************************************************************************/
+
+package cli
+
+import (
+	"bytes"
+	"strings"
+)
+
+//AnsiStyle offers a set of styles for the VT100 SGR (Select Graphic Recognition) command.
+type AnsiStyle string
+
+const (
+	//AnsiNormal reverts all styles to default.
+	AnsiNormal AnsiStyle = "0"
+	//AnsiInverse swaps foreground and background color.
+	AnsiInverse AnsiStyle = "7"
+	//AnsiBlack is a foreground color.
+	AnsiBlack AnsiStyle = "30"
+	//AnsiRed is a foreground color.
+	AnsiRed AnsiStyle = "31"
+	//AnsiGreen is a foreground color.
+	AnsiGreen AnsiStyle = "32"
+	//AnsiYellow is a foreground color.
+	AnsiYellow AnsiStyle = "33"
+	//AnsiBlue is a foreground color.
+	AnsiBlue AnsiStyle = "34"
+	//AnsiMagenta is a foreground color.
+	AnsiMagenta AnsiStyle = "35"
+	//AnsiCyan is a foreground color.
+	AnsiCyan AnsiStyle = "36"
+	//AnsiWhite is a foreground color.
+	AnsiWhite AnsiStyle = "37"
+	//AnsiOnBlack is a background color.
+	AnsiOnBlack AnsiStyle = "40"
+	//AnsiOnRed is a background color.
+	AnsiOnRed AnsiStyle = "41"
+	//AnsiOnGreen is a background color.
+	AnsiOnGreen AnsiStyle = "42"
+	//AnsiOnYellow is a background color.
+	AnsiOnYellow AnsiStyle = "43"
+	//AnsiOnBlue is a background color.
+	AnsiOnBlue AnsiStyle = "44"
+	//AnsiOnMagenta is a background color.
+	AnsiOnMagenta AnsiStyle = "45"
+	//AnsiOnCyan is a background color.
+	AnsiOnCyan AnsiStyle = "46"
+	//AnsiOnWhite is a background color.
+	AnsiOnWhite AnsiStyle = "47"
+)
+
+//StyledString is a string with attached style information for displaying on a terminal.
+type StyledString struct {
+	Text   string
+	Styles []AnsiStyle
+}
+
+//Styled is syntactic sugar for a StyledString instance.
+func Styled(text string, styles ...AnsiStyle) StyledString {
+	return StyledString{text, styles}
+}
+
+//DisplayString returns the string for writing on a terminal emulator.
+func (s StyledString) DisplayString(withReset bool) []byte {
+	strs := make([]string, len(s.Styles))
+	for idx, s := range s.Styles {
+		strs[idx] = string(s)
+	}
+	str := "\x1B[" + strings.Join(strs, ";") + "m" + s.Text
+	if withReset {
+		str += "\x1B[0m"
+	}
+	return []byte(str)
+}
+
+//StyledText is a sequence of styled strings.
+type StyledText []StyledString
+
+//DisplayString returns the string for writing on a terminal emulator.
+func (t StyledText) DisplayString(withReset bool) []byte {
+	var buf bytes.Buffer
+	for _, s := range t {
+		buf.Write(s.DisplayString(false))
+	}
+	if withReset {
+		buf.Write([]byte("\x1B[0m"))
+	}
+	return buf.Bytes()
+}