lume/cmd/help.go

61 lines
1.1 KiB
Go

package lumecmd
import (
"flag"
"fmt"
)
func init() {
var cmdName string = "help"
fs := flag.NewFlagSet(cmdName, flag.ExitOnError)
RegisterCommand(cmdName, Command{
Func: HelpCmd,
Flags: fs,
Use: "<command>",
Short: "Show help for a command",
})
}
func HelpCmd(args CmdArgs) (int, error) {
argv := args.Flags.Args()
if len(argv) == 0 {
printHelp(commandRegistry)
} else if len(argv) >= 1 {
subCmd, ok := commandRegistry[argv[0]]
if !ok {
fmt.Printf("unknown command: %s\n", argv[0])
return 1, nil
}
if subCmd.Use != "" {
fmt.Printf("usage:\n lume %s %s\n", subCmd.Name, subCmd.Use)
fmt.Println()
}
fmt.Print("flags:\n")
subCmd.Flags.PrintDefaults()
}
return 0, nil
}
func printHelp(commands map[string]Command) {
var maxLen, cmdLen int
for _, c := range commands {
cmdLen = len(c.Name)
if cmdLen > maxLen {
maxLen = cmdLen
}
}
fmt.Printf("usage:\n lume <command> [<args...>]")
fmt.Println()
fmt.Println("\ncommands:")
for _, c := range commands {
fmt.Printf(" %-*s %s\n", maxLen, c.Name, c.Short)
}
}