first commit

output/style/color.go

@@ -0,0 +1,51 @@
+package style
+
+const (
+	Black   Color = "0"
+	Red     Color = "1"
+	Green   Color = "2"
+	Yellow  Color = "3"
+	Blue    Color = "4"
+	Magenta Color = "5"
+	Cyan    Color = "6"
+	White   Color = "7"
+	Default Color = "9"
+)
+
+const (
+	Bold       Option = "122"
+	Underscore Option = "424"
+	Blink      Option = "525"
+	Reverse    Option = "727"
+	Conseal    Option = "828"
+)
+
+const (
+	ActionSet   = 1
+	ActionUnset = 2
+)
+
+type Option string
+
+func (o Option) Apply(action int) string {
+	v := string(o)
+
+	switch action {
+	case ActionSet:
+		return v[0:1]
+	case ActionUnset:
+		return v[1:]
+	}
+
+	return ""
+}
+
+type Color string
+
+func (c Color) Apply(action int) string {
+	if action == ActionSet {
+		return string(c)
+	}
+
+	return string(Default)
+}

output/style/style.go

@@ -0,0 +1,88 @@
+package style
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+	"sync"
+)
+
+//nolint: gochecknoglobals
+var (
+	styles = map[string]Style{
+		"error":    {Foreground: White, Background: Red},
+		"info":     {Foreground: Green},
+		"comment":  {Foreground: Yellow},
+		"question": {Foreground: Black, Background: Cyan},
+	}
+	stylesMu sync.Mutex
+	empty    = Style{}
+)
+
+var (
+	ErrNotFound       = errors.New("console: style not found")
+	ErrDuplicateStyle = errors.New("console: Register called twice")
+)
+
+func Empty() Style {
+	return empty
+}
+
+func Find(name string) (Style, error) {
+	if st, has := styles[name]; has {
+		return st, nil
+	}
+
+	return empty, ErrNotFound
+}
+
+func Register(name string, style Style) error {
+	stylesMu.Lock()
+	defer stylesMu.Unlock()
+
+	if _, has := styles[name]; has {
+		return fmt.Errorf("%w for style %s", ErrDuplicateStyle, name)
+	}
+
+	styles[name] = style
+
+	return nil
+}
+
+func MustRegister(name string, style Style) {
+	if err := Register(name, style); err != nil {
+		panic(err)
+	}
+}
+
+type Style struct {
+	Background Color
+	Foreground Color
+	Options    []Option
+}
+
+func (s Style) Apply(msg string) string {
+	return s.Set(ActionSet) + msg + s.Set(ActionUnset)
+}
+
+func (s Style) Set(action int) string {
+	style := make([]string, 0, len(s.Options))
+
+	if s.Foreground != "" {
+		style = append(style, "3"+s.Foreground.Apply(action))
+	}
+
+	if s.Background != "" {
+		style = append(style, "4"+s.Background.Apply(action))
+	}
+
+	for _, opt := range s.Options {
+		style = append(style, opt.Apply(action))
+	}
+
+	if len(style) == 0 {
+		return ""
+	}
+
+	return "\033[" + strings.Join(style, ";") + "m"
+}