Import of https://github.com/ciena/voltctl at commit 40d61fbf3f910ed4017cf67c9c79e8e1f82a33a5

Change-Id: I8464c59e60d76cb8612891db3303878975b5416c
diff --git a/vendor/github.com/jessevdk/go-flags/help.go b/vendor/github.com/jessevdk/go-flags/help.go
new file mode 100644
index 0000000..d380305
--- /dev/null
+++ b/vendor/github.com/jessevdk/go-flags/help.go
@@ -0,0 +1,491 @@
+// Copyright 2012 Jesse van den Kieboom. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flags
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"runtime"
+	"strings"
+	"unicode/utf8"
+)
+
+type alignmentInfo struct {
+	maxLongLen      int
+	hasShort        bool
+	hasValueName    bool
+	terminalColumns int
+	indent          bool
+}
+
+const (
+	paddingBeforeOption                 = 2
+	distanceBetweenOptionAndDescription = 2
+)
+
+func (a *alignmentInfo) descriptionStart() int {
+	ret := a.maxLongLen + distanceBetweenOptionAndDescription
+
+	if a.hasShort {
+		ret += 2
+	}
+
+	if a.maxLongLen > 0 {
+		ret += 4
+	}
+
+	if a.hasValueName {
+		ret += 3
+	}
+
+	return ret
+}
+
+func (a *alignmentInfo) updateLen(name string, indent bool) {
+	l := utf8.RuneCountInString(name)
+
+	if indent {
+		l = l + 4
+	}
+
+	if l > a.maxLongLen {
+		a.maxLongLen = l
+	}
+}
+
+func (p *Parser) getAlignmentInfo() alignmentInfo {
+	ret := alignmentInfo{
+		maxLongLen:      0,
+		hasShort:        false,
+		hasValueName:    false,
+		terminalColumns: getTerminalColumns(),
+	}
+
+	if ret.terminalColumns <= 0 {
+		ret.terminalColumns = 80
+	}
+
+	var prevcmd *Command
+
+	p.eachActiveGroup(func(c *Command, grp *Group) {
+		if c != prevcmd {
+			for _, arg := range c.args {
+				ret.updateLen(arg.Name, c != p.Command)
+			}
+		}
+
+		for _, info := range grp.options {
+			if !info.canCli() {
+				continue
+			}
+
+			if info.ShortName != 0 {
+				ret.hasShort = true
+			}
+
+			if len(info.ValueName) > 0 {
+				ret.hasValueName = true
+			}
+
+			l := info.LongNameWithNamespace() + info.ValueName
+
+			if len(info.Choices) != 0 {
+				l += "[" + strings.Join(info.Choices, "|") + "]"
+			}
+
+			ret.updateLen(l, c != p.Command)
+		}
+	})
+
+	return ret
+}
+
+func wrapText(s string, l int, prefix string) string {
+	var ret string
+
+	if l < 10 {
+		l = 10
+	}
+
+	// Basic text wrapping of s at spaces to fit in l
+	lines := strings.Split(s, "\n")
+
+	for _, line := range lines {
+		var retline string
+
+		line = strings.TrimSpace(line)
+
+		for len(line) > l {
+			// Try to split on space
+			suffix := ""
+
+			pos := strings.LastIndex(line[:l], " ")
+
+			if pos < 0 {
+				pos = l - 1
+				suffix = "-\n"
+			}
+
+			if len(retline) != 0 {
+				retline += "\n" + prefix
+			}
+
+			retline += strings.TrimSpace(line[:pos]) + suffix
+			line = strings.TrimSpace(line[pos:])
+		}
+
+		if len(line) > 0 {
+			if len(retline) != 0 {
+				retline += "\n" + prefix
+			}
+
+			retline += line
+		}
+
+		if len(ret) > 0 {
+			ret += "\n"
+
+			if len(retline) > 0 {
+				ret += prefix
+			}
+		}
+
+		ret += retline
+	}
+
+	return ret
+}
+
+func (p *Parser) writeHelpOption(writer *bufio.Writer, option *Option, info alignmentInfo) {
+	line := &bytes.Buffer{}
+
+	prefix := paddingBeforeOption
+
+	if info.indent {
+		prefix += 4
+	}
+
+	if option.Hidden {
+		return
+	}
+
+	line.WriteString(strings.Repeat(" ", prefix))
+
+	if option.ShortName != 0 {
+		line.WriteRune(defaultShortOptDelimiter)
+		line.WriteRune(option.ShortName)
+	} else if info.hasShort {
+		line.WriteString("  ")
+	}
+
+	descstart := info.descriptionStart() + paddingBeforeOption
+
+	if len(option.LongName) > 0 {
+		if option.ShortName != 0 {
+			line.WriteString(", ")
+		} else if info.hasShort {
+			line.WriteString("  ")
+		}
+
+		line.WriteString(defaultLongOptDelimiter)
+		line.WriteString(option.LongNameWithNamespace())
+	}
+
+	if option.canArgument() {
+		line.WriteRune(defaultNameArgDelimiter)
+
+		if len(option.ValueName) > 0 {
+			line.WriteString(option.ValueName)
+		}
+
+		if len(option.Choices) > 0 {
+			line.WriteString("[" + strings.Join(option.Choices, "|") + "]")
+		}
+	}
+
+	written := line.Len()
+	line.WriteTo(writer)
+
+	if option.Description != "" {
+		dw := descstart - written
+		writer.WriteString(strings.Repeat(" ", dw))
+
+		var def string
+
+		if len(option.DefaultMask) != 0 {
+			if option.DefaultMask != "-" {
+				def = option.DefaultMask
+			}
+		} else {
+			def = option.defaultLiteral
+		}
+
+		var envDef string
+		if option.EnvDefaultKey != "" {
+			var envPrintable string
+			if runtime.GOOS == "windows" {
+				envPrintable = "%" + option.EnvDefaultKey + "%"
+			} else {
+				envPrintable = "$" + option.EnvDefaultKey
+			}
+			envDef = fmt.Sprintf(" [%s]", envPrintable)
+		}
+
+		var desc string
+
+		if def != "" {
+			desc = fmt.Sprintf("%s (default: %v)%s", option.Description, def, envDef)
+		} else {
+			desc = option.Description + envDef
+		}
+
+		writer.WriteString(wrapText(desc,
+			info.terminalColumns-descstart,
+			strings.Repeat(" ", descstart)))
+	}
+
+	writer.WriteString("\n")
+}
+
+func maxCommandLength(s []*Command) int {
+	if len(s) == 0 {
+		return 0
+	}
+
+	ret := len(s[0].Name)
+
+	for _, v := range s[1:] {
+		l := len(v.Name)
+
+		if l > ret {
+			ret = l
+		}
+	}
+
+	return ret
+}
+
+// WriteHelp writes a help message containing all the possible options and
+// their descriptions to the provided writer. Note that the HelpFlag parser
+// option provides a convenient way to add a -h/--help option group to the
+// command line parser which will automatically show the help messages using
+// this method.
+func (p *Parser) WriteHelp(writer io.Writer) {
+	if writer == nil {
+		return
+	}
+
+	wr := bufio.NewWriter(writer)
+	aligninfo := p.getAlignmentInfo()
+
+	cmd := p.Command
+
+	for cmd.Active != nil {
+		cmd = cmd.Active
+	}
+
+	if p.Name != "" {
+		wr.WriteString("Usage:\n")
+		wr.WriteString(" ")
+
+		allcmd := p.Command
+
+		for allcmd != nil {
+			var usage string
+
+			if allcmd == p.Command {
+				if len(p.Usage) != 0 {
+					usage = p.Usage
+				} else if p.Options&HelpFlag != 0 {
+					usage = "[OPTIONS]"
+				}
+			} else if us, ok := allcmd.data.(Usage); ok {
+				usage = us.Usage()
+			} else if allcmd.hasCliOptions() {
+				usage = fmt.Sprintf("[%s-OPTIONS]", allcmd.Name)
+			}
+
+			if len(usage) != 0 {
+				fmt.Fprintf(wr, " %s %s", allcmd.Name, usage)
+			} else {
+				fmt.Fprintf(wr, " %s", allcmd.Name)
+			}
+
+			if len(allcmd.args) > 0 {
+				fmt.Fprintf(wr, " ")
+			}
+
+			for i, arg := range allcmd.args {
+				if i != 0 {
+					fmt.Fprintf(wr, " ")
+				}
+
+				name := arg.Name
+
+				if arg.isRemaining() {
+					name = name + "..."
+				}
+
+				if !allcmd.ArgsRequired {
+					fmt.Fprintf(wr, "[%s]", name)
+				} else {
+					fmt.Fprintf(wr, "%s", name)
+				}
+			}
+
+			if allcmd.Active == nil && len(allcmd.commands) > 0 {
+				var co, cc string
+
+				if allcmd.SubcommandsOptional {
+					co, cc = "[", "]"
+				} else {
+					co, cc = "<", ">"
+				}
+
+				visibleCommands := allcmd.visibleCommands()
+
+				if len(visibleCommands) > 3 {
+					fmt.Fprintf(wr, " %scommand%s", co, cc)
+				} else {
+					subcommands := allcmd.sortedVisibleCommands()
+					names := make([]string, len(subcommands))
+
+					for i, subc := range subcommands {
+						names[i] = subc.Name
+					}
+
+					fmt.Fprintf(wr, " %s%s%s", co, strings.Join(names, " | "), cc)
+				}
+			}
+
+			allcmd = allcmd.Active
+		}
+
+		fmt.Fprintln(wr)
+
+		if len(cmd.LongDescription) != 0 {
+			fmt.Fprintln(wr)
+
+			t := wrapText(cmd.LongDescription,
+				aligninfo.terminalColumns,
+				"")
+
+			fmt.Fprintln(wr, t)
+		}
+	}
+
+	c := p.Command
+
+	for c != nil {
+		printcmd := c != p.Command
+
+		c.eachGroup(func(grp *Group) {
+			first := true
+
+			// Skip built-in help group for all commands except the top-level
+			// parser
+			if grp.Hidden || (grp.isBuiltinHelp && c != p.Command) {
+				return
+			}
+
+			for _, info := range grp.options {
+				if !info.canCli() || info.Hidden {
+					continue
+				}
+
+				if printcmd {
+					fmt.Fprintf(wr, "\n[%s command options]\n", c.Name)
+					aligninfo.indent = true
+					printcmd = false
+				}
+
+				if first && cmd.Group != grp {
+					fmt.Fprintln(wr)
+
+					if aligninfo.indent {
+						wr.WriteString("    ")
+					}
+
+					fmt.Fprintf(wr, "%s:\n", grp.ShortDescription)
+					first = false
+				}
+
+				p.writeHelpOption(wr, info, aligninfo)
+			}
+		})
+
+		var args []*Arg
+		for _, arg := range c.args {
+			if arg.Description != "" {
+				args = append(args, arg)
+			}
+		}
+
+		if len(args) > 0 {
+			if c == p.Command {
+				fmt.Fprintf(wr, "\nArguments:\n")
+			} else {
+				fmt.Fprintf(wr, "\n[%s command arguments]\n", c.Name)
+			}
+
+			descStart := aligninfo.descriptionStart() + paddingBeforeOption
+
+			for _, arg := range args {
+				argPrefix := strings.Repeat(" ", paddingBeforeOption)
+				argPrefix += arg.Name
+
+				if len(arg.Description) > 0 {
+					argPrefix += ":"
+					wr.WriteString(argPrefix)
+
+					// Space between "arg:" and the description start
+					descPadding := strings.Repeat(" ", descStart-len(argPrefix))
+					// How much space the description gets before wrapping
+					descWidth := aligninfo.terminalColumns - 1 - descStart
+					// Whitespace to which we can indent new description lines
+					descPrefix := strings.Repeat(" ", descStart)
+
+					wr.WriteString(descPadding)
+					wr.WriteString(wrapText(arg.Description, descWidth, descPrefix))
+				} else {
+					wr.WriteString(argPrefix)
+				}
+
+				fmt.Fprintln(wr)
+			}
+		}
+
+		c = c.Active
+	}
+
+	scommands := cmd.sortedVisibleCommands()
+
+	if len(scommands) > 0 {
+		maxnamelen := maxCommandLength(scommands)
+
+		fmt.Fprintln(wr)
+		fmt.Fprintln(wr, "Available commands:")
+
+		for _, c := range scommands {
+			fmt.Fprintf(wr, "  %s", c.Name)
+
+			if len(c.ShortDescription) > 0 {
+				pad := strings.Repeat(" ", maxnamelen-len(c.Name))
+				fmt.Fprintf(wr, "%s  %s", pad, c.ShortDescription)
+
+				if len(c.Aliases) > 0 {
+					fmt.Fprintf(wr, " (aliases: %s)", strings.Join(c.Aliases, ", "))
+				}
+
+			}
+
+			fmt.Fprintln(wr)
+		}
+	}
+
+	wr.Flush()
+}