package container

import (
	"fmt"

	"github.com/TrueCloudLab/frostfs-node/pkg/morph/client"
	cid "github.com/TrueCloudLab/frostfs-sdk-go/container/id"
	"github.com/TrueCloudLab/frostfs-sdk-go/user"
)

// List returns a list of container identifiers belonging
// to the specified user of FrostFS system. The list is composed
// through Container contract call.
//
// Returns the identifiers of all FrostFS containers if pointer
// to user identifier is nil.
func (c *Client) List(idUser *user.ID) ([]cid.ID, error) {
	var rawID []byte

	if idUser != nil {
		rawID = idUser.WalletBytes()
	}

	prm := client.TestInvokePrm{}
	prm.SetMethod(listMethod)
	prm.SetArgs(rawID)

	res, err := c.client.TestInvoke(prm)
	if err != nil {
		return nil, fmt.Errorf("could not perform test invocation (%s): %w", listMethod, err)
	} else if ln := len(res); ln != 1 {
		return nil, fmt.Errorf("unexpected stack item count (%s): %d", listMethod, ln)
	}

	res, err = client.ArrayFromStackItem(res[0])
	if err != nil {
		return nil, fmt.Errorf("could not get stack item array from stack item (%s): %w", listMethod, err)
	}

	cidList := make([]cid.ID, 0, len(res))
	for i := range res {
		rawID, err := client.BytesFromStackItem(res[i])
		if err != nil {
			return nil, fmt.Errorf("could not get byte array from stack item (%s): %w", listMethod, err)
		}

		var id cid.ID

		err = id.Decode(rawID)
		if err != nil {
			return nil, fmt.Errorf("decode container ID: %w", err)
		}

		cidList = append(cidList, id)
	}

	return cidList, nil
}