//

// AppLastCompiledRulesStore.swift

// DuckDuckGo

//

// Copyright © 2022 DuckDuckGo. All rights reserved.

//

// 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.

//

import Foundation

import BrowserServicesKit

import TrackerRadarKit

struct AppLastCompiledRules: LastCompiledRules, Codable {

var name: String

var trackerData: TrackerData

var etag: String

var identifier: ContentBlockerRulesIdentifier

}

protocol Storage {

func persist(_ data: Data) -> Bool

var data: Data? { get }

}

struct LastCompiledRulesStorage: Storage {

private enum Const {

static let filename = "LastCompiledRules"

static let path = FileManager

.default

.containerURL(forSecurityApplicationGroupIdentifier: ContentBlockerStoreConstants.groupName)!

.appendingPathComponent(filename)

}

func persist(_ data: Data) -> Bool {

do {

try data.write(to: Const.path, options: .atomic)

return true

} catch {

return false

}

}

var data: Data? {

do {

return try Data(contentsOf: Const.path)

} catch {

return nil

}

}

}

final class AppLastCompiledRulesStore: LastCompiledRulesStore {

private var storage: Storage

init(with storage: Storage = LastCompiledRulesStorage()) {

self.storage = storage

}

var rules: [LastCompiledRules] {

guard

let data = storage.data,

let rules = try? JSONDecoder().decode([AppLastCompiledRules].self, from: data) else {

return []

}

return rules

}

func update(with contentBlockerRules: [ContentBlockerRulesManager.Rules]) {

let rules = contentBlockerRules.map { rules in

AppLastCompiledRules(name: rules.name,

trackerData: rules.trackerData,

etag: rules.etag,

identifier: rules.identifier)

}

if !rules.isEmpty, let encodedRules = try? JSONEncoder().encode(rules) {

_ = storage.persist(encodedRules)

}

}

}