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)
	SetTWServer(ctx context.Context, id, versionCode, serverKey string) (domain.Group, error)
	SetChannelGains(ctx context.Context, id, channel string) (domain.Group, error)
	SetChannelLosses(ctx context.Context, id, channel string) (domain.Group, error)
	List(ctx context.Context, params domain.ListGroupsParams) ([]domain.Group, error)
}

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

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

func NewBot(token string, groupSvc GroupService, 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, 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 {
	if err := b.registerCommand(&groupCommand{svc: b.groupSvc, client: b.client}); 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()
}