/macos/RoonKit/Sources/RoonKit/Services/TransportService.swift at 62d7639db14c0da6343f024647c5477995940c70

// Copyright 2025 Shota FUJI
//
// 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.
//
// SPDX-License-Identifier: Apache-2.0

import Foundation

public struct TransportService {
	public static let id = "com.roonlabs.transport:2"

	public struct SingleLineDisplay: Decodable, Hashable {
		public let line: String

		public enum CodingKeys: String, CodingKey {
			case line = "line1"
		}
	}

	public struct DoubleLineDisplay: Decodable, Hashable {
		public let line1: String
		public let line2: String?
	}

	public struct TripleLineDisplay: Decodable, Hashable {
		public let line1: String
		public let line2: String?
		public let line3: String?
	}

	public struct NowPlaying: Decodable, Hashable {
		public let seekPosition: UInt64?
		public let length: UInt64?
		public let imageKey: String?
		public let singleLine: SingleLineDisplay
		public let doubleLine: DoubleLineDisplay
		public let tripleLine: TripleLineDisplay

		public enum CodingKeys: String, CodingKey {
			case seekPosition = "seek_position"
			case length = "length"
			case imageKey = "image_key"
			case singleLine = "one_line"
			case doubleLine = "two_line"
			case tripleLine = "three_line"
		}
	}

	public enum PlaybackState: String, Decodable {
		case playing
		case paused
		case loading
		case stopped
	}

	public struct OutputVolume: Decodable, Hashable {
		public let type: String
		public let min: Float64?
		public let max: Float64?
		public let value: Float64?
		public let step: Float64?
		public let isMuted: Bool?

		public enum CodingKeys: String, CodingKey {
			case type = "type"
			case min = "min"
			case max = "max"
			case value = "value"
			case step = "step"
			case isMuted = "is_muted"
		}
	}

	public struct Output: Decodable, Identifiable, Hashable {
		public let id: String
		public let displayName: String
		public let volume: OutputVolume?

		public enum CodingKeys: String, CodingKey {
			case id = "output_id"
			case displayName = "display_name"
			case volume = "volume"
		}
	}

	public struct Zone: Decodable, Identifiable, Hashable {
		public let id: String
		public let displayName: String
		public let outputs: [Output]
		public let nowPlaying: NowPlaying?
		public let state: PlaybackState
		public let isPreviousAllowed: Bool?
		public let isNextAllowed: Bool?
		public let isPauseAllowed: Bool?
		public let isPlayAllowed: Bool?
		public let isSeekAllowed: Bool?

		public enum CodingKeys: String, CodingKey {
			case id = "zone_id"
			case displayName = "display_name"
			case outputs = "outputs"
			case nowPlaying = "now_playing"
			case state = "state"
			case isPreviousAllowed = "is_previous_allowed"
			case isNextAllowed = "is_next_allowed"
			case isPauseAllowed = "is_pause_allowed"
			case isPlayAllowed = "is_play_allowed"
			case isSeekAllowed = "is_seek_allowed"
		}
	}

	public struct SeekChangeEvent: Decodable {
		public let zoneID: String
		public let seekPosition: UInt64?

		public enum CodingKeys: String, CodingKey {
			case zoneID = "zone_id"
			case seekPosition = "seek_position"
		}
	}

	public struct ZoneChangeEvent: Decodable {
		private let _removedZoneIDs: [String]?
		private let _addedZones: [Zone]?
		private let _changedZones: [Zone]?
		private let _seekChanges: [SeekChangeEvent]?

		public var removedZoneIDs: [String] {
			_removedZoneIDs ?? []
		}

		public var addedZones: [Zone] {
			_addedZones ?? []
		}

		public var changedZones: [Zone] {
			_changedZones ?? []
		}

		public var seekChanges: [SeekChangeEvent] {
			_seekChanges ?? []
		}

		public enum CodingKeys: String, CodingKey {
			case _removedZoneIDs = "zones_removed"
			case _addedZones = "zones_added"
			case _changedZones = "zones_changed"
			case _seekChanges = "zones_seek_changed"
		}

		public init?(_ msg: Moo) {
			do {
				self = try msg.json(type: Self.self)
			} catch {
				return nil
			}
		}
	}
}

// MARK: - Subscribe changes to zone

extension TransportService {
	public struct SubscribeZoneChangesRequest: Encodable {
		public let subscriptionID: String

		public init(subscriptionID: String) {
			self.subscriptionID = subscriptionID
		}

		public init(subscriptionID: any BinaryInteger) {
			self.subscriptionID = String(subscriptionID, radix: 10)
		}

		public enum CodingKeys: String, CodingKey {
			case subscriptionID = "subscription_key"
		}
	}

	public struct SubscribeZoneChangesResponse: Decodable {
		public enum DecodeError: Error {
			case unexpectedStatus(String)
			case bodyError(Moo.JsonBodyError)
		}

		public let zones: [Zone]

		public init(_ msg: Moo) throws(DecodeError) {
			guard msg.service == "Subscribed" else {
				throw .unexpectedStatus(msg.service)
			}

			do {
				self = try msg.json(type: Self.self)
			} catch {
				throw .bodyError(error)
			}
		}
	}
}

extension Moo {
	public init(
		subscribeZoneChange: TransportService.SubscribeZoneChangesRequest
	) throws {
		try self.init(
			jsonBody: subscribeZoneChange,
			service: "\(TransportService.id)/subscribe_zones"
		)
	}
}

// MARK: - Send playback control

extension TransportService {
	public enum ControlAction: String, Codable {
		case play, pause, playpause, stop, previous, next
	}

	public struct ControlRequest: Codable {
		public let zoneOrOutputID: String
		public let control: ControlAction

		public enum CodingKeys: String, CodingKey {
			case zoneOrOutputID = "zone_or_output_id"
			case control = "control"
		}

		public init(zoneID: String, control: ControlAction) {
			self.zoneOrOutputID = zoneID
			self.control = control
		}
	}

	public struct ControlResponse: Codable {
		public enum DecodeError: Error {
			case nonSuccess
		}

		public init(_ msg: Moo) throws(DecodeError) {
			guard msg.service == "Success" else {
				throw .nonSuccess
			}
		}
	}
}

extension Moo {
	public init(control: TransportService.ControlRequest) throws {
		try self.init(jsonBody: control, service: "\(TransportService.id)/control")
	}
}

// MARK: - Seek current playing song

extension TransportService {
	public enum SeekMode: String, Codable {
		case relative, absolute
	}

	public struct SeekRequest: Codable {
		public let zoneOrOutputID: String
		public let mode: SeekMode
		public let seconds: Int64

		public enum CodingKeys: String, CodingKey {
			case zoneOrOutputID = "zone_or_output_id"
			case mode = "how"
			case seconds = "seconds"
		}

		public init(zoneID: String, seconds: Int64, mode: SeekMode = .absolute) {
			self.zoneOrOutputID = zoneID
			self.mode = mode
			self.seconds = seconds
		}
	}

	public struct SeekResponse: Codable {
		public enum DecodeError: Error {
			case nonSuccess
		}

		public init(_ msg: Moo) throws(DecodeError) {
			guard msg.service == "Success" else {
				throw .nonSuccess
			}
		}
	}
}

extension Moo {
	public init(seek: TransportService.SeekRequest) throws {
		try self.init(jsonBody: seek, service: "\(TransportService.id)/seek")
	}
}

// MARK: - Change output volume

extension TransportService {
	public enum ChangeVolumeMode: String, Codable {
		case absolute, relative
		case relativeStep = "relative_step"
	}

	public struct ChangeVolumeRequest: Codable {
		public let outputID: String
		public let mode: ChangeVolumeMode
		public let value: Float64

		public enum CodingKeys: String, CodingKey {
			case outputID = "output_id"
			case mode = "how"
			case value = "value"
		}

		public init(
			outputID: String,
			value: Float64,
			mode: ChangeVolumeMode = .absolute
		) {
			self.outputID = outputID
			self.value = value
			self.mode = mode
		}
	}

	public struct ChangeVolumeResponse: Codable {
		public enum DecodeError: Error {
			case nonSuccess
		}

		public init(_ msg: Moo) throws(DecodeError) {
			guard msg.service == "Success" else {
				throw .nonSuccess
			}
		}
	}
}

extension Moo {
	public init(changeVolume: TransportService.ChangeVolumeRequest) throws {
		try self.init(
			jsonBody: changeVolume,
			service: "\(TransportService.id)/change_volume"
		)
	}
}