handler.go

package main

import (
	"bytes"
	"fmt"
	"github.com/bwmarrin/discordgo"
	"github.com/mattn/go-shellwords"
)

func handler(s *discordgo.Session, m *discordgo.MessageCreate) {
	if m.Author.ID == s.State.User.ID {
		return
	}

	args, err := shellwords.Parse(m.Content)
	if logOnError(err) {
		return
	}
	command, ok := dish.Commands[args[0]]
	if !ok {
		return
	}

	if !checkIdentity(command, m.Author, discordgo.Roles{}) {
		return
	}

	if command.Args {
		args = append(command.Command, args[1:]...)
	} else {
		args = command.Command
	}
	result, err := command.Run(args)
	if logOnError(err) {
		return
	}

	lines := bytes.Split(result, []byte{'\n'})
	buf := &bytes.Buffer{}
	msg, err := s.ChannelMessage(m.ChannelID, m.ID)
	if logOnError(err) {
		return
	}
	for i, line := range lines {
		if (buf.Len()+len(line)+13 > 2000) || (i == len(lines)-1) {
			text := fmt.Sprintf("```ansi\n%s```", buf.String())
			msg, err = s.ChannelMessageSendReply(m.ChannelID, text, msg.Reference())
			if err != nil {
				fmt.Println(err)
				return
			}
			buf.Truncate(0)
		}
		buf.Write(line)
		buf.WriteByte('\n')
	}
}

func checkIdentity(command Command, user *discordgo.User, roles discordgo.Roles) bool {
	ids := make([]string, len(roles)+1, len(roles)+1)
	for i, role := range roles {
		ids[i] = role.ID
	}
	ids[len(ids)-1] = user.ID
	fmt.Println(command.WhiteList)
	fmt.Println(command.BlackList)
	for _, check := range command.WhiteList {
		for _, id := range ids {
			if check == id {
				return true
			}
		}
	}
	for _, check := range command.BlackList {
		for _, id := range ids {
			if check == id {
				return false
			}
		}
	}
	return len(command.WhiteList) == 0
}