package main

import (
	"fmt"
	"sort"
	"strings"
)

type HelpPlugin struct{}

func (p HelpPlugin) Name() string { return "help" }
func (p HelpPlugin) ShortHelp() string { return "List commands or get help for a specific command" }
func (p HelpPlugin) DetailedHelp() string {
	return "help [command]\n\nWith no arguments, lists all available commands.\nWith a command name, shows detailed help for that command.\n\nExamples:\n  help\n  help math"
}
func (p HelpPlugin) Execute(msg BotMessage, args string) string {
	if args == "" {
		names := make([]string, 0, len(registry))
		for name := range registry {
			names = append(names, name)
		}
		sort.Strings(names)

		var sb strings.Builder
		for _, name := range names {
			fmt.Fprintf(&sb, "%s — %s\n", name, registry[name].ShortHelp())
		}
		return sb.String()
	}

	if plugin, ok := registry[args]; ok {
		return plugin.DetailedHelp()
	}

	return fmt.Sprintf("No help found for '%s'. Try 'help' to see all commands.", args)
}