package usecase

import (
	"context"
	"fmt"
	"strings"

	"gitea.computernetthings.ru/yash/crypto_alert_bot/internal/entities"
)

func (uc *Usecase) InstrumentList(ctx context.Context, userID entities.UserID, offset, limit int) ([]entities.Instrument, error) {
	instruments, err := uc.storage.InstrumentList(ctx, userID, offset, limit)
	if err != nil {
		uc.log.Error("failed to list instruments", "offset", offset, "limit", limit, "err", err)
		return nil, fmt.Errorf("failed to list instruments: %w", err)
	}

	return instruments, nil
}

func (uc *Usecase) CreateInstrument(ctx context.Context, instrument *entities.Instrument) (entities.InstrumentID, error) {
	id, err := uc.storage.CreateInstrument(ctx, instrument)
	if err != nil {
		uc.log.Error("failed to create instrument", "instrument", instrument, "err", err)
		return "", fmt.Errorf("failed to create instrument: %w", err)
	}

	return id, nil
}

func (uc *Usecase) RemoveUserInstrument(ctx context.Context, userID entities.UserID, instrumentID entities.InstrumentID) error {
	if err := uc.storage.RemoveUserInstrument(ctx, userID, instrumentID); err != nil {
		uc.log.Error("failed to remove user instrument", "user_id", userID, "instrument_id", instrumentID, "err", err)
		return fmt.Errorf("failed to remove user instrument: %w", err)
	}
	return nil
}

// AddUserInstrument ensures the instrument exists in the DB (creating it if needed)
// and links it to the given user. Returns the instrument with its ID filled in.
func (uc *Usecase) AddUserInstrument(ctx context.Context, userID entities.UserID, base, quote string) (*entities.Instrument, error) {
	base = strings.ToUpper(strings.TrimSpace(base))
	quote = strings.ToUpper(strings.TrimSpace(quote))

	instr := &entities.Instrument{BaseCurrency: base, QuoteCurrency: quote}

	id, err := uc.storage.CreateInstrument(ctx, instr)
	if err != nil {
		uc.log.Error("failed to upsert instrument", "base", base, "quote", quote, "err", err)
		return nil, fmt.Errorf("failed to upsert instrument: %w", err)
	}
	instr.ID = id

	if err := uc.storage.AddUserInstrument(ctx, userID, id); err != nil {
		uc.log.Error("failed to add user instrument", "user_id", userID, "instrument_id", id, "err", err)
		return nil, fmt.Errorf("failed to add user instrument: %w", err)
	}

	return instr, nil
}