Initial commit, WIP

color.go

@@ -0,0 +1,134 @@
+package color
+
+import (
+	"strconv"
+	"strings"
+
+	"fmt"
+)
+
+type Color struct {
+	params []Parameter
+}
+
+// Parameter defines a single SGR Code
+type Parameter int
+
+const (
+	FgBlack Parameter = iota + 30
+	FgRed
+	FgGreen
+	FgYellow
+	FgBlue
+	FgMagent
+	FgCyan
+	FgWhite
+)
+
+const (
+	BgBlack Parameter = iota + 40
+	BgRed
+	BgGreen
+	BgYellow
+	BgBlue
+	BgMagent
+	BgCyan
+	BgWhite
+)
+
+const (
+	Reset Parameter = iota
+	Bold
+	Faint
+	Italic
+	Underline
+	BlinkSlow
+	BlinkRapid
+	ReverseVideo
+	Concealed
+	CrossedOut
+)
+
+var (
+	Black  = &Color{params: []Parameter{FgBlack}}
+	Red    = &Color{params: []Parameter{FgRed}}
+	Green  = &Color{params: []Parameter{FgGreen}}
+	Yellow = &Color{params: []Parameter{FgYellow}}
+	Blue   = &Color{params: []Parameter{FgBlue}}
+	Magent = &Color{params: []Parameter{FgMagent}}
+	Cyan   = &Color{params: []Parameter{FgCyan}}
+	White  = &Color{params: []Parameter{FgWhite}}
+)
+
+func New(value ...Parameter) *Color {
+	c := &Color{params: make([]Parameter, 0)}
+	c.Add(value...)
+	return c
+}
+
+func (c *Color) Bold() *Color {
+	c.Add(Bold)
+	return c
+}
+
+func (c *Color) Add(value ...Parameter) *Color {
+	c.params = append(c.params, value...)
+	return c
+}
+
+func (c *Color) prepend(value Parameter) {
+	c.params = append(c.params, 0)
+	copy(c.params[1:], c.params[0:])
+	c.params[0] = value
+}
+
+// Printf formats according to a format specifier and writes to standard output.
+// It returns the number of bytes written and any write error encountered.
+func (c *Color) Printf(format string, a ...interface{}) (n int, err error) {
+	c.Set()
+	defer Unset()
+
+	return fmt.Printf(format, a...)
+}
+
+// Print formats using the default formats for its operands and writes to
+// standard output. Spaces are added between operands when neither is a
+// string. It returns the number of bytes written and any write error
+// encountered.
+func (c *Color) Print(a ...interface{}) (n int, err error) {
+	c.Set()
+	defer Unset()
+
+	return fmt.Print(a...)
+}
+
+// Println formats using the default formats for its operands and writes to
+// standard output. Spaces are always added between operands and a newline is
+// appended. It returns the number of bytes written and any write error
+// encountered.
+func (c *Color) Println(a ...interface{}) (n int, err error) {
+	c.Set()
+	defer Unset()
+
+	return fmt.Println(a...)
+}
+
+// sequence returns a formated SGR sequence to be plugged into a "\033[...m"
+// an example output might be: "1;36" -> bold cyan
+func (c *Color) sequence() string {
+	format := make([]string, len(c.params))
+	for i, v := range c.params {
+		format[i] = strconv.Itoa(int(v))
+	}
+
+	return strings.Join(format, ";")
+}
+
+// Set sets the SGR sequence.
+func (c *Color) Set() {
+	fmt.Printf("\033[%sm", c.sequence())
+}
+
+func Unset() {
+	fmt.Print("\033[0m")
+}

color_test.go

@@ -0,0 +1,31 @@
+package color
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"time"
+
+	"testing"
+)
+
+func TestColor(t *testing.T) {
+	go func() {
+		scanner := bufio.NewScanner(os.Stdout)
+		for scanner.Scan() {
+			fmt.Println(scanner.Text()) // Println will add back the final '\n'
+		}
+	}()
+
+	time.Sleep(time.Millisecond * 300)
+
+	c := Cyan.Bold()
+	c.Println("ankara")
+
+	// New(FgGreen, Bold).Begin()
+	// fmt.Println("san francisco")
+	// End()
+
+	// Output:
+	// ankara
+}