// Copyright © 2017 Mikael Berthe <mikael@lilotux.net>

//

// Licensed under the MIT license.

// Please see the LICENSE file is this directory.

package colors

import (

	"strconv"

	"strings"

	"github.com/pkg/errors"

)

// Style values

const (

	Bold = iota + 1

	Faint

	Italic

	Underline

	BlinkSlow

	BlinkFast

	Inverse

	Hide

	CrossedOut

)

// Styles contains style names

var Styles = [...]string{

	"bold",

	"faint",

	"italic",

	"underline",

	"blink-slow",

	"blink-fast",

	"inverse",

	"hide",

	"crossed-out",

}

// Color values

const (

	Black = iota

	Red

	Green

	Yellow

	Blue

	Magenta

	Cyan

	White

)

// Colors contains color names

var Colors = [...]string{

	"black",

	"red",

	"green",

	"yellow",

	"blue",

	"magenta",

	"cyan",

	"white",

}

// ANSICode returns an ANSI escape sequence string for the requested output

func ANSICode(fg, bg, style int) string {

	var seq []string

	if fg >= 0 {

		seq = append(seq, strconv.Itoa(30+fg))

	}

	if bg >= 0 {

		seq = append(seq, strconv.Itoa(40+bg))

	}

	if style >= 0 {

		seq = append(seq, strconv.Itoa(1+style))

	}

	if len(seq) == 0 {

		return "\x1b[" + "0" + "m" // Reset sequence

	}

	return "\x1b[" + strings.Join(seq, ";") + "m"

}

// ANSICodeString returns an ANSI escape sequence string for the requested

// output.

// The description is a coma-separated list of foreground color, background

// color and style: [fg],[bg],[style]

// An empty description or "reset" returns the ANSI reset sequence.

func ANSICodeString(desc string) (string, error) {

	col := [2]int{-1, -1} // fg, bg

	style := -1

	if desc == "" || desc == "reset" {

		return ANSICode(col[0], col[1], style), nil

	}

	styles := strings.SplitN(desc, ",", 3)

	for i, s := range styles {

		if s == "" {

			continue

		}

		switch {

		case i < 2: // Color

			for n, c := range Colors {

				if c == s {

					col[i] = n

					break

				}

			}

			if col[i] == -1 {

				return ANSICode(-1, -1, -1),

					errors.Errorf("color name '%s' not found", s)

			}

		case i == 2: // Style

			for n, sn := range Styles {

				if sn == s {

					style = n

					break

				}

			}

			if style == -1 {

				return ANSICode(-1, -1, -1),

					errors.Errorf("style name '%s' not found", s)

			}

		}

	}

	return ANSICode(col[0], col[1], style), nil

}