styles.go

package main

import (
	"github.com/fatih/color"
)

func contains(arr []color.Attribute, needle color.Attribute) bool {
	for _, a := range arr {
		if needle == a {
			return true
		}
	}
	return false
}
func isSubset(sub []color.Attribute, super []color.Attribute) bool {
	for _, sb := range sub {
		if !contains(super, sb) {
			return false
		}
	}
	return true
}

func terribleContrast(styles []color.Attribute) bool {
	// http://www.thinkui.co.uk/2017/02/high-contrast-colours/
	terrible_contrast := make([][]color.Attribute, 1)
	terrible_contrast[0] = []color.Attribute{color.FgBlue, color.BgGreen}

	for _, pair := range terrible_contrast {
		if isSubset(pair, styles) {
			return true
		}
	}
	return false
}

func ApplyStyles(s string, styles ...color.Attribute) string {
	if s == "" || len(styles) == 0 {
		return s
	} else {
		c := color.New(styles...)
		if terribleContrast(styles) {
			c.Add(color.Bold)
			c.Add(color.FgWhite)
		}
		c.EnableColor()
		return c.Sprint(s)
	}
}

func StylePrompt(prompt Prompt, default_color int, symlink_color int, open_write int) {
	lastFSRoot := "/"
	currentFSRoot := "/"
	path := "/"
	mounts := GetMounts()

	for i := 1; i < len(prompt); i += 1 {
		path += prompt[i].Name
		style := prompt[i].NameStyle

		if !prompt[i].Shadowed {
			if IsLink(path) {
				style = append(style, color.Attribute(symlink_color))
				path = ResolvedPath(path)
			} else {
				style = append(style, color.Attribute(default_color))
			}

			if IsOpenWrite(path) {
				style = append(style, color.Attribute(open_write))
			}
		}
		currentFSRoot = GetPathRoot(path, mounts)
		if currentFSRoot != lastFSRoot {
			style = append(style, color.Underline)
			lastFSRoot = currentFSRoot
		}
		prompt[i].NameStyle = style
		path += "/"
	}
}