describer.go

package clif

import (
	"fmt"
	"os"
	"path/filepath"
	"sort"
	"strings"
)

// DescribeCli command implements the string rendering of a cli which help uses.
// Can be overwritten at users discretion.
var DescribeCli = func(c *Cli) string {

	// name + version
	line := "<headline>" + c.Name + "<reset>"
	if c.Version != "" {
		line += " <debug>(" + c.Version + ")<reset>"
	}
	lines := []string{line}

	// description
	if c.Description != "" {
		lines = append(lines, "<info>"+c.Description+"<reset>\n")
	}

	// usage
	prog := filepath.Base(os.Args[0])
	lines = append(lines, fmt.Sprintf("<subline>Usage:<reset>\n  %s command [arg ..] [--opt val ..]\n", prog))

	// commands
	lines = append(lines, "<subline>Available commands:<reset>")
	max := 0
	ordered := make(map[string][]*Command)
	prefices := make([]string, 0)
	for _, cmd := range c.Commands {
		if l := len(cmd.Name); l > max {
			max = l
		}
		prefix := ""
		if i := strings.Index(cmd.Name, ":"); i > -1 {
			prefix = cmd.Name[0:i]
		}
		if ordered[prefix] == nil {
			prefices = append(prefices, prefix)
			ordered[prefix] = make([]*Command, 0)
		}
		ordered[prefix] = append(ordered[prefix], cmd)
	}
	sort.Strings(prefices)
	for _, prefix := range prefices {
		if prefix != "" {
			lines = append(lines, fmt.Sprintf(" <subline>%s<reset>", prefix))
		}
		sort.Sort(CommandsSort(ordered[prefix]))
		for _, cmd := range ordered[prefix] {
			lines = append(lines, fmt.Sprintf("  <info>%-"+fmt.Sprintf("%d", max)+"s<reset>  %s", cmd.Name, cmd.Usage))
		}
	}

	return strings.Join(lines, "\n") + "\n"
}


// DescribeCommand implements the string rendering of a command which help uses.
// Can be overwritten at users discretion.
var DescribeCommand = func(c *Command) string {
	lines := []string{"Command: <headline>" + c.Name + "<reset>"}

	if c.Description != "" {
		lines = append(lines, []string{"<info>" + c.Description + "<reset>", ""}...)
	} else if c.Usage != "" {
		lines = append(lines, []string{"<info>" + c.Usage + "<reset>", ""}...)
	}

	lines = append(lines, "<subline>Usage:<reset>")
	usage := []string{c.Name}
	args := make([][]string, 0)
	argMax := 0
	opts := make([][]string, 0)
	optMax := 0
	for _, p := range c.Arguments {
		var short string
		usg := p.Usage
		short = p.Name
		usgInfo := []string{}
		if p.Multiple {
			short = short + " ..."
			usgInfo = append(usgInfo, `<debug>mult<reset>`)
		}
		if p.Required {
			usgInfo = append(usgInfo, `<important>req<reset>`)
		} else {
			short = fmt.Sprintf("[%s]", short)
		}
		if p.Env != "" {
			usgInfo = append(usgInfo, fmt.Sprintf(`env: <debug>%s<reset>`, p.Env))
		}
		if p.Default != "" {
			usgInfo = append(usgInfo, fmt.Sprintf(`default: <debug>"%s"<reset>`, p.Default))
		}
		if l := len(p.Name); l > argMax {
			argMax = l
		}
		usage = append(usage, short)
		if len(usgInfo) > 0 {
			usg += " ("+ strings.Join(usgInfo, ", ")+ ")"
		}
		args = append(args, []string{p.Name, usg})
	}

	for _, p := range c.Options {
		short := fmt.Sprintf("--%s", p.Name)
		if p.Alias != "" {
			short += "|-" + p.Alias
		}
		if !p.Flag {
			short += " val"
		}
		long := short
		usg := p.Usage
		usgInfo := []string{}
		if p.Multiple {
			short = short + " ..."
			usgInfo = append(usgInfo, `<debug>mult<reset>`)
		}
		if !p.Required {
			short = "[" + short + "]"
		} else {
			usgInfo = append(usgInfo, `<important>req<reset>`)
		}
		if p.Env != "" {
			usgInfo = append(usgInfo, fmt.Sprintf(`env: <debug>%s<reset>`, p.Env))
		}
		if p.Default != "" {
			usgInfo = append(usgInfo, fmt.Sprintf(`default: <debug>"%s"<reset>`, p.Default))
		}
		if l := len(long); l > optMax {
			optMax = l
		}
		usage = append(usage, short)
		if len(usgInfo) > 0 {
			usg += " ("+ strings.Join(usgInfo, ", ")+ ")"
		}
		opts = append(opts, []string{long, usg})
	}
	lines = append(lines, "  "+strings.Join(usage, " "))
	lines = append(lines, "")

	if len(args) > 0 {
		lines = append(lines, "<subline>Arguments:<reset>")
		for _, l := range args {
			lines = append(lines, fmt.Sprintf("  <info>%-"+fmt.Sprintf("%d", argMax)+"s<reset>  %s", l[0], l[1]))
		}
		lines = append(lines, "")
	}

	if len(opts) > 0 {
		lines = append(lines, "<subline>Options:<reset>")
		for _, l := range opts {
			lines = append(lines, fmt.Sprintf("  <info>%-"+fmt.Sprintf("%d", optMax)+"s<reset>  %s", l[0], l[1]))
		}
		lines = append(lines, "")
	}

	return strings.Join(lines, "\n") + "\n"
}