// Copyright 2020-2022 Buf Technologies, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package storagemem

import (
	"bytes"

	"github.com/bufbuild/buf/private/pkg/storage"
	"github.com/bufbuild/buf/private/pkg/storage/storagemem/internal"
	"github.com/bufbuild/buf/private/pkg/storage/storageutil"
)

type readObjectCloser struct {
	storageutil.ObjectInfo

	reader *bytes.Reader
	closed bool
}

func newReadObjectCloser(immutableObject *internal.ImmutableObject) *readObjectCloser {
	return &readObjectCloser{
		ObjectInfo: immutableObject.ObjectInfo,
		reader:     bytes.NewReader(immutableObject.Data()),
	}
}

func (r *readObjectCloser) Read(p []byte) (int, error) {
	if r.closed {
		return 0, storage.ErrClosed
	}
	return r.reader.Read(p)
}

func (r *readObjectCloser) Close() error {
	if r.closed {
		return storage.ErrClosed
	}
	r.closed = true
	return nil
}
