// Copyright 2020-2021 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 storageos implements an os-backed storage Bucket.
package storageos

import (
	"github.com/bufbuild/buf/internal/pkg/storage"
)

// Provider provides new ReadWriteBuckets.
type Provider interface {
	// NewReadWriteBucket returns a new OS bucket.
	//
	// Only regular files are handled, that is Exists should only be called
	// for regular files, Get and Put only work for regular files, Put
	// automatically calls Mkdir, and Walk only calls f on regular files.
	//
	// The root path is expected to be normalized, however the root path
	// can be absolute or jump context.
	//
	// Not thread-safe.
	NewReadWriteBucket(rootPath string, options ...ReadWriteBucketOption) (storage.ReadWriteBucket, error)
}

// NewProvider returns a new Provider.
func NewProvider(options ...ProviderOption) Provider {
	return newProvider(options...)
}

// ProviderOption is an option for a new Provider.
type ProviderOption func(*provider)

// ProviderWithSymlinks returns a ProviderOption that results in symlink support.
//
// Note that ReadWriteBucketWithSymlinksEnabled still needs to be passed for a given
// ReadWriteBucket to have symlinks followed.
func ProviderWithSymlinks() ProviderOption {
	return func(provider *provider) {
		provider.symlinks = true
	}
}

// ReadWriteBucketOption is an option for a new ReadWriteBucket.
type ReadWriteBucketOption func(*readWriteBucketOptions)

// ReadWriteBucketWithSymlinksIfSupported returns a ReadWriteBucketOption that results
// in symlink support being enabled for this bucket. If the Provider did not have symlink
// support, this is a no-op.
func ReadWriteBucketWithSymlinksIfSupported() ReadWriteBucketOption {
	return func(readWriteBucketOptions *readWriteBucketOptions) {
		readWriteBucketOptions.symlinksIfSupported = true
	}
}
