act/pkg/common/draw.go
2020-02-04 16:38:41 -08:00

144 lines
3.1 KiB
Go

package common
import (
"fmt"
"io"
"os"
"strings"
)
// Style is a specific style
type Style int
// Styles
const (
StyleDoubleLine = iota
StyleSingleLine
StyleDashedLine
StyleNoLine
)
// NewPen creates a new pen
func NewPen(style Style, color int) *Pen {
bgcolor := 49
if os.Getenv("CLICOLOR") == "0" {
color = 0
bgcolor = 0
}
return &Pen{
style: style,
color: color,
bgcolor: bgcolor,
}
}
type styleDef struct {
cornerTL string
cornerTR string
cornerBL string
cornerBR string
lineH string
lineV string
}
var styleDefs = []styleDef{
{"\u2554", "\u2557", "\u255a", "\u255d", "\u2550", "\u2551"},
//{"\u250c", "\u2510", "\u2514", "\u2518", "\u2500", "\u2502"},
{"\u256d", "\u256e", "\u2570", "\u256f", "\u2500", "\u2502"},
{"\u250c", "\u2510", "\u2514", "\u2518", "\u254c", "\u254e"},
{" ", " ", " ", " ", " ", " "},
}
// Pen struct
type Pen struct {
style Style
color int
bgcolor int
}
// Drawing struct
type Drawing struct {
buf *strings.Builder
width int
}
func (p *Pen) drawTopBars(buf io.Writer, labels ...string) {
style := styleDefs[p.style]
for _, label := range labels {
bar := strings.Repeat(style.lineH, len(label)+2)
fmt.Fprintf(buf, " ")
fmt.Fprintf(buf, "\x1b[%d;%dm", p.color, p.bgcolor)
fmt.Fprintf(buf, "%s%s%s", style.cornerTL, bar, style.cornerTR)
fmt.Fprintf(buf, "\x1b[%dm", 0)
}
fmt.Fprintf(buf, "\n")
}
func (p *Pen) drawBottomBars(buf io.Writer, labels ...string) {
style := styleDefs[p.style]
for _, label := range labels {
bar := strings.Repeat(style.lineH, len(label)+2)
fmt.Fprintf(buf, " ")
fmt.Fprintf(buf, "\x1b[%d;%dm", p.color, p.bgcolor)
fmt.Fprintf(buf, "%s%s%s", style.cornerBL, bar, style.cornerBR)
fmt.Fprintf(buf, "\x1b[%dm", 0)
}
fmt.Fprintf(buf, "\n")
}
func (p *Pen) drawLabels(buf io.Writer, labels ...string) {
style := styleDefs[p.style]
for _, label := range labels {
fmt.Fprintf(buf, " ")
fmt.Fprintf(buf, "\x1b[%d;%dm", p.color, p.bgcolor)
fmt.Fprintf(buf, "%s %s %s", style.lineV, label, style.lineV)
fmt.Fprintf(buf, "\x1b[%dm", 0)
}
fmt.Fprintf(buf, "\n")
}
// DrawArrow between boxes
func (p *Pen) DrawArrow() *Drawing {
drawing := &Drawing{
buf: new(strings.Builder),
width: 1,
}
fmt.Fprintf(drawing.buf, "\x1b[%dm", p.color)
fmt.Fprintf(drawing.buf, "\u2b07")
fmt.Fprintf(drawing.buf, "\x1b[%dm", 0)
return drawing
}
// DrawBoxes to draw boxes
func (p *Pen) DrawBoxes(labels ...string) *Drawing {
width := 0
for _, l := range labels {
width += len(l) + 2 + 2 + 1
}
drawing := &Drawing{
buf: new(strings.Builder),
width: width,
}
p.drawTopBars(drawing.buf, labels...)
p.drawLabels(drawing.buf, labels...)
p.drawBottomBars(drawing.buf, labels...)
return drawing
}
// Draw to writer
func (d *Drawing) Draw(writer io.Writer, centerOnWidth int) {
padSize := (centerOnWidth - d.GetWidth()) / 2
if padSize < 0 {
padSize = 0
}
for _, l := range strings.Split(d.buf.String(), "\n") {
if len(l) > 0 {
padding := strings.Repeat(" ", padSize)
fmt.Fprintf(writer, "%s%s\n", padding, l)
}
}
}
// GetWidth of drawing
func (d *Drawing) GetWidth() int {
return d.width
}