aminal/terminal/sgr.go

package terminal

import (
	"fmt"
	"strconv"

	"github.com/liamg/aminal/buffer"
)

func sgrSequenceHandler(params []string, intermediate string, terminal *Terminal) error {

	if len(params) == 0 {
		return nil
	}

	param := params[0]

	switch param {
	case "00", "0", "":
		attr := terminal.ActiveBuffer().CursorAttr()
		*attr = buffer.CellAttributes{
			FgColour: terminal.config.ColourScheme.Foreground,
			BgColour: terminal.config.ColourScheme.Background,
		}
	case "1", "01":
		terminal.ActiveBuffer().CursorAttr().Bold = true
	case "2", "02":
		terminal.ActiveBuffer().CursorAttr().Dim = true
	case "4", "04":
		terminal.ActiveBuffer().CursorAttr().Underline = true
	case "5", "05":
		terminal.ActiveBuffer().CursorAttr().Blink = true
	case "7", "07":
		terminal.ActiveBuffer().CursorAttr().Reverse = true
	case "8", "08":
		terminal.ActiveBuffer().CursorAttr().Hidden = true
	case "21":
		terminal.ActiveBuffer().CursorAttr().Bold = false
	case "22":
		terminal.ActiveBuffer().CursorAttr().Dim = false
	case "24":
		terminal.ActiveBuffer().CursorAttr().Underline = false
	case "25":
		terminal.ActiveBuffer().CursorAttr().Blink = false
	case "27":
		terminal.ActiveBuffer().CursorAttr().Reverse = false
	case "28":
		terminal.ActiveBuffer().CursorAttr().Hidden = false
	case "39":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.Foreground
	case "30":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.Black
	case "31":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.Red
	case "32":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.Green
	case "33":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.Yellow
	case "34":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.Blue
	case "35":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.Magenta
	case "36":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.Cyan
	case "37":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.White
	case "90":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.DarkGrey
	case "91":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.LightRed
	case "92":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.LightGreen
	case "93":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.LightYellow
	case "94":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.LightBlue
	case "95":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.LightMagenta
	case "96":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.LightCyan
	case "97":
		terminal.ActiveBuffer().CursorAttr().FgColour = terminal.config.ColourScheme.White
	case "49":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.Background
	case "40":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.Black
	case "41":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.Red
	case "42":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.Green
	case "43":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.Yellow
	case "44":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.Blue
	case "45":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.Magenta
	case "46":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.Cyan
	case "47":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.White
	case "100":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.DarkGrey
	case "101":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.LightRed
	case "102":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.LightGreen
	case "103":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.LightYellow
	case "104":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.LightBlue
	case "105":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.LightMagenta
	case "106":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.LightCyan
	case "107":
		terminal.ActiveBuffer().CursorAttr().BgColour = terminal.config.ColourScheme.White
	case "38": // set foreground
		if len(params) > 2 {
			switch params[1] {
			case "5":
				// 8 bit colour
				colNum, err := strconv.Atoi(params[2])
				if err == nil && colNum < 256 && colNum >= 0 {
					terminal.ActiveBuffer().CursorAttr().FgColour = get8BitSGRColour(uint8(colNum), terminal)
				}
			case "2":
				// 24 bit colour
			}
		}
	case "48": // set background
		if len(params) > 2 {
			switch params[1] {
			case "5":
				// 8 bit colour
				colNum, err := strconv.Atoi(params[2])
				if err == nil && colNum < 256 && colNum >= 0 {
					terminal.ActiveBuffer().CursorAttr().BgColour = get8BitSGRColour(uint8(colNum), terminal)
				}
			case "2":
				// 24 bit colour
			}
		}
	default:
		return fmt.Errorf("Unknown SGR control sequence: (ESC[%s%sm)", param, intermediate)
	}

	//terminal.logger.Debugf("SGR control sequence: (ESC[%s%sm)", param, intermediate)

	return nil
}

func get8BitSGRColour(colNum uint8, terminal *Terminal) [3]float32 {

	// https://en.wikipedia.org/wiki/ANSI_escape_code#8-bit

	switch colNum {
	case 0:
		return terminal.config.ColourScheme.Black
	case 1:
		return terminal.config.ColourScheme.Red
	case 2:
		return terminal.config.ColourScheme.Green
	case 3:
		return terminal.config.ColourScheme.Yellow
	case 4:
		return terminal.config.ColourScheme.Blue
	case 5:
		return terminal.config.ColourScheme.Magenta
	case 6:
		return terminal.config.ColourScheme.Cyan
	case 7:
		return terminal.config.ColourScheme.White
	case 8:
		return terminal.config.ColourScheme.DarkGrey
	case 9:
		return terminal.config.ColourScheme.LightRed
	case 10:
		return terminal.config.ColourScheme.LightGreen
	case 11:
		return terminal.config.ColourScheme.LightYellow
	case 12:
		return terminal.config.ColourScheme.LightBlue
	case 13:
		return terminal.config.ColourScheme.LightMagenta
	case 14:
		return terminal.config.ColourScheme.LightCyan
	case 15:
		return terminal.config.ColourScheme.White
	}

	if colNum < 232 {

		index := int(colNum - 16) // 0-216
		rgb := (index * 0xffffff) / 216
		r := float32((rgb&0xff0000)>>16) / 0xff
		g := float32((rgb&0xff00)>>8) / 0xff
		b := float32(rgb&0xff) / 0xff

		return [3]float32{r, g, b}
	}

	c := float32(colNum-232) / 0x18
	return [3]float32{c, c, c}
}