Show color palettes

README.md

@@ -48,6 +48,7 @@ $ go get -u github.com/jingweno/ccat
 $ ccat FILE1 FILE2 ...
 $ ccat --bg=dark FILE1 FILE 2 ... # dark background
 $ ccat --color-code String="_darkblue_" --color-code Plaintext="darkred" FILE # set color codes
+$ ccat --palette # show palette
 $ ccat # read from standard input
 $ curl https://raw.githubusercontent.com/jingweno/ccat/master/main.go | ccat
 ```

ccat.go

@@ -15,23 +15,23 @@ type CCatPrinter interface {
 }
 
 type AutoColorPrinter struct {
-	ColorDefs ColorDefs
+	ColorPalettes ColorPalettes
 }
 
 func (a AutoColorPrinter) Print(r io.Reader, w io.Writer) error {
 	if isatty.IsTerminal(uintptr(syscall.Stdout)) {
-		return ColorPrinter{a.ColorDefs}.Print(r, w)
+		return ColorPrinter{a.ColorPalettes}.Print(r, w)
 	} else {
 		return PlainTextPrinter{}.Print(r, w)
 	}
 }
 
 type ColorPrinter struct {
-	ColorDefs ColorDefs
+	ColorPalettes ColorPalettes
 }
 
 func (c ColorPrinter) Print(r io.Reader, w io.Writer) error {
-	return CPrint(r, w, c.ColorDefs)
+	return CPrint(r, w, c.ColorPalettes)
 }
 
 type PlainTextPrinter struct {

color.go

@@ -3,12 +3,34 @@ package main
 import (
 	"bytes"
 	"fmt"
+	"sort"
 	"strings"
 )
 
 const esc = "\033["
 
-var ColorCodes = map[string]string{
+type ColorCodes map[string]string
+
+func (c ColorCodes) String() string {
+	var cc []string
+	for k, _ := range c {
+		if k == "" {
+			continue
+		}
+
+		cc = append(cc, k)
+	}
+	sort.Strings(cc)
+
+	var s []string
+	for _, ss := range cc {
+		s = append(s, Colorize(ss, ss))
+	}
+
+	return strings.Join(s, ", ")
+}
+
+var colorCodes = ColorCodes{
 	"":          "",
 	"reset":     esc + "39;49;00m",
 	"bold":      esc + "01m",
@@ -43,14 +65,14 @@ func init() {
 	}
 
 	for i, x := 0, 30; i < len(darkColors); i, x = i+1, x+1 {
-		ColorCodes[darkColors[i]] = esc + fmt.Sprintf("%dm", x)
-		ColorCodes[lightColors[i]] = esc + fmt.Sprintf("%d;01m", x)
+		colorCodes[darkColors[i]] = esc + fmt.Sprintf("%dm", x)
+		colorCodes[lightColors[i]] = esc + fmt.Sprintf("%d;01m", x)
 	}
 
-	ColorCodes["darkteal"] = ColorCodes["turquoise"]
-	ColorCodes["darkyellow"] = ColorCodes["brown"]
-	ColorCodes["fuscia"] = ColorCodes["fuchsia"]
-	ColorCodes["white"] = ColorCodes["bold"]
+	colorCodes["darkteal"] = colorCodes["turquoise"]
+	colorCodes["darkyellow"] = colorCodes["brown"]
+	colorCodes["fuscia"] = colorCodes["fuchsia"]
+	colorCodes["white"] = colorCodes["bold"]
 }
 
 /*
@@ -69,26 +91,26 @@ func Colorize(attr, text string) string {
 	result := new(bytes.Buffer)
 
 	if strings.HasPrefix(attr, "+") && strings.HasSuffix(attr, "+") {
-		result.WriteString(ColorCodes["blink"])
+		result.WriteString(colorCodes["blink"])
 		attr = strings.TrimPrefix(attr, "+")
 		attr = strings.TrimSuffix(attr, "+")
 	}
 
 	if strings.HasPrefix(attr, "*") && strings.HasSuffix(attr, "*") {
-		result.WriteString(ColorCodes["bold"])
+		result.WriteString(colorCodes["bold"])
 		attr = strings.TrimPrefix(attr, "*")
 		attr = strings.TrimSuffix(attr, "*")
 	}
 
 	if strings.HasPrefix(attr, "_") && strings.HasSuffix(attr, "_") {
-		result.WriteString(ColorCodes["underline"])
+		result.WriteString(colorCodes["underline"])
 		attr = strings.TrimPrefix(attr, "_")
 		attr = strings.TrimSuffix(attr, "_")
 	}
 
-	result.WriteString(ColorCodes[attr])
+	result.WriteString(colorCodes[attr])
 	result.WriteString(text)
-	result.WriteString(ColorCodes["reset"])
+	result.WriteString(colorCodes["reset"])
 
 	return result.String()
 }

color_test.go

@@ -1,27 +1,23 @@
 package main
 
-import (
-	"testing"
+import "testing"
 
-	"github.com/jingweno/ccat/Godeps/_workspace/src/github.com/sourcegraph/syntaxhighlight"
-)
-
-func Test_ColorDefs_Set(t *testing.T) {
-	defs := ColorDefs{
-		syntaxhighlight.String: "blue",
+func Test_ColorPalette_Set(t *testing.T) {
+	palettes := ColorPalettes{
+		stringKind: "blue",
 	}
 
-	ok := defs.Set("foo", "bar")
+	ok := palettes.Set("foo", "bar")
 	if ok {
 		t.Errorf("setting color code foo should not be ok")
 	}
 
-	ok = defs.Set("String", "baz")
+	ok = palettes.Set("String", "baz")
 	if !ok {
 		t.Errorf("setting color code String should be ok")
 	}
 
-	if defs[syntaxhighlight.String] != "baz" {
+	if palettes[stringKind] != "baz" {
 		t.Errorf("color code of String should be baz")
 	}
 }

main.go

@@ -13,33 +13,52 @@ const (
 )
 
 type ccatCmd struct {
-	BG         string
-	Color      string
-	ColorCodes mapValue
+	BG          string
+	Color       string
+	ColorCodes  mapValue
+	ShowPalette bool
 }
 
 func (c *ccatCmd) Run(cmd *cobra.Command, args []string) {
-	var colorDefs ColorDefs
+	var colorPalettes ColorPalettes
 	if c.BG == "dark" {
-		colorDefs = DarkColorDefs
+		colorPalettes = DarkColorPalettes
 	} else {
-		colorDefs = LightColorDefs
+		colorPalettes = LightColorPalettes
 	}
 
+	// override color codes
 	for k, v := range c.ColorCodes {
-		ok := colorDefs.Set(k, v)
+		ok := colorPalettes.Set(k, v)
 		if !ok {
 			log.Fatal(fmt.Errorf("unknown color code: %s", k))
 		}
 	}
 
+	if c.ShowPalette {
+		fmt.Printf(`Applied color codes:
+
+%s
+
+Color code is in the format of:
+
+  color       normal color
+  *color*     bold color
+  _color_     underlined color
+  +color+     blinking color
+
+Value of color can be %s
+`, colorPalettes, colorCodes)
+		return
+	}
+
 	var printer CCatPrinter
 	if c.Color == "always" {
-		printer = ColorPrinter{colorDefs}
+		printer = ColorPrinter{colorPalettes}
 	} else if c.Color == "never" {
 		printer = PlainTextPrinter{}
 	} else {
-		printer = AutoColorPrinter{colorDefs}
+		printer = AutoColorPrinter{colorPalettes}
 	}
 
 	// if there's no args, read from stdin
@@ -66,6 +85,7 @@ func main() {
 		Example: `$ ccat FILE1 FILE2 ...
   $ ccat --bg=dark FILE1 FILE2 ... # dark background
   $ ccat --color-code String="_darkblue_" --color-code Plaintext="darkred" FILE # set color codes
+  $ ccat --palette # show palette
   $ ccat # read from standard input
   $ curl https://raw.githubusercontent.com/jingweno/ccat/master/main.go | ccat`,
 		Run: ccatCmd.Run,
@@ -79,7 +99,8 @@ Flags:
 {{.LocalFlags.FlagUsages}}
 Using color is auto both by default and with --color=auto. With --color=auto,
 ccat emits color codes only when standard output is connected to a terminal.
-Color codes can be changed with --color-code KEY=VALUE.
+Color codes can be changed with --color-code KEY=VALUE. List of color codes can
+be found with --palette.
 
 Examples:
   {{ .Example }}`
@@ -88,6 +109,7 @@ Examples:
 	rootCmd.PersistentFlags().StringVarP(&ccatCmd.BG, "bg", "", "light", `set to "light" or "dark" depending on the terminal's background`)
 	rootCmd.PersistentFlags().StringVarP(&ccatCmd.Color, "color", "C", "auto", `colorize the output; value can be "never", "always" or "auto"`)
 	rootCmd.PersistentFlags().VarP(&ccatCmd.ColorCodes, "color-code", "G", `set color codes`)
+	rootCmd.PersistentFlags().BoolVarP(&ccatCmd.ShowPalette, "palette", "", false, `show color palettes`)
 
 	rootCmd.Execute()
 }