dcbot/internal/discord/bot.go

package discord

import (
	"context"
	"fmt"

	"gitea.dwysokinski.me/twhelp/dcbot/internal/domain"
	"gitea.dwysokinski.me/twhelp/dcbot/internal/twhelp"
	"github.com/bwmarrin/discordgo"
)

type GroupService interface {
	Create(ctx context.Context, params domain.CreateGroupParams) (domain.Group, error)
	SetChannelGains(ctx context.Context, id, serverID, channel string) (domain.Group, error)
	SetChannelLosses(ctx context.Context, id, serverID, channel string) (domain.Group, error)
	List(ctx context.Context, params domain.ListGroupsParams) ([]domain.Group, error)
	Delete(ctx context.Context, id, serverID string) error
}

type MonitorService interface {
	Create(ctx context.Context, groupID, serverID, tribeTag string) (domain.Monitor, error)
}

type TWHelpClient interface {
	ListVersions(ctx context.Context) ([]twhelp.Version, error)
}

type Bot struct {
	s          *discordgo.Session
	groupSvc   GroupService
	monitorSvc MonitorService
	client     TWHelpClient
}

func NewBot(token string, groupSvc GroupService, monitorSvc MonitorService, client TWHelpClient) (*Bot, error) {
	s, err := discordgo.New("Bot " + token)
	if err != nil {
		return nil, fmt.Errorf("discordgo.New: %w", err)
	}

	if err = s.Open(); err != nil {
		return nil, fmt.Errorf("s.Open: %w", err)
	}

	b := &Bot{s: s, groupSvc: groupSvc, monitorSvc: monitorSvc, client: client}
	if err = b.registerCommands(); err != nil {
		_ = s.Close()
		return nil, fmt.Errorf("couldn't register commands: %w", err)
	}

	return b, nil
}

func (b *Bot) registerCommands() error {
	commands := []command{
		&groupCommand{svc: b.groupSvc, client: b.client},
		&monitorCommand{svc: b.monitorSvc},
	}

	for _, c := range commands {
		if err := b.registerCommand(c); err != nil {
			return err
		}
	}

	return nil
}

type command interface {
	name() string
	register(s *discordgo.Session) error
}

func (b *Bot) registerCommand(cmd command) error {
	if err := cmd.register(b.s); err != nil {
		return fmt.Errorf("couldn't register command '%s': %w", cmd.name(), err)
	}
	return nil
}

func (b *Bot) Close() error {
	return b.s.Close()
}