package telegram

import (
	"context"
	"fmt"

	"github.com/TelegramExchange/tgex-backend/tg_parser/internal/domain"
	"github.com/google/uuid"
	"github.com/gotd/td/tg"
)

func (t *Telegram) ParseChannelMeta(ctx context.Context, username string) (domain.Channel, error) {
	resolved, err := t.API().ContactsResolveUsername(ctx, &tg.ContactsResolveUsernameRequest{
		Username: username,
	})
	if err != nil {
		return domain.Channel{}, fmt.Errorf("resolve username: %w", err)
	}

	if len(resolved.Chats) == 0 {
		return domain.Channel{}, fmt.Errorf("no chats in resolve result")
	}

	ch, ok := resolved.Chats[0].(*tg.Channel)
	if !ok {
		return domain.Channel{}, fmt.Errorf("not a channel")
	}

	req := []tg.InputDialogPeerClass{
		&tg.InputDialogPeer{
			Peer: &tg.InputPeerChannel{
				ChannelID:  ch.ID,
				AccessHash: ch.AccessHash,
			},
		},
	}

	dialogs, err := t.API().MessagesGetPeerDialogs(ctx, req)
	if err != nil {
		return domain.Channel{}, fmt.Errorf("peer dialogs: %w", err)
	}

	pts := 0
	if len(dialogs.Dialogs) > 0 {
		d, ok := dialogs.Dialogs[0].(*tg.Dialog)
		if ok {
			pts = d.Pts
		}
	}

	return domain.Channel{
		ID:         uuid.New(),
		TelegramID: domain.ChatIDFromChannelID(ch.ID),
		Username:   username,
		Title:      ch.Title,
		AccessHash: ch.AccessHash,
		Pts:        pts,
	}, nil
}