build: initial setup of the library

Author: renaudjenny

.gitignore

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+.DS_Store
+/.build
+/Packages
+/*.xcodeproj
+xcuserdata/

Package.swift

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+// swift-tools-version:5.2
+// The swift-tools-version declares the minimum version of Swift required to build this package.
+
+import PackageDescription
+
+let package = Package(
+    name: "SwiftTTSCombine",
+    platforms: [
+        .iOS(.v13),
+        .macOS(.v10_15),
+    ],
+    products: [
+        .library(
+            name: "SwiftTTSCombine",
+            targets: ["SwiftTTSCombine"]),
+    ],
+    dependencies: [],
+    targets: [
+        .target(
+            name: "SwiftTTSCombine",
+            dependencies: []),
+        .testTarget(
+            name: "SwiftTTSCombineTests",
+            dependencies: ["SwiftTTSCombine"]),
+    ]
+)

README.md

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+# SwiftTTSCombine
+
+A very straightforward Combine wrapper around TTS part of AVFoundation/AVSpeechSynthesizer to allow you using Text to Speech with ease.

Sources/SwiftTTSCombine/SwiftTTSCombine.swift

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+import Foundation
+import Combine
+import AVFoundation
+
+public protocol TTSEngine: class {
+    var rateRatio: Float { get set }
+    var voice: AVSpeechSynthesisVoice? { get set }
+    func speak(string: String)
+    var isSpeakingPublisher: AnyPublisher<Bool, Never> { get }
+    var speakingProgressPublisher: AnyPublisher<Double, Never> { get }
+}
+
+public final class Engine: NSObject, ObservableObject {
+    @Published private var isSpeaking: Bool = false
+    @Published private var speakingProgress: Double = 0.0
+    public var rateRatio: Float
+    public var voice: AVSpeechSynthesisVoice?
+    private let speechSynthesizer = AVSpeechSynthesizer()
+
+    public init(
+        rateRatio: Float = 1.0,
+        voice: AVSpeechSynthesisVoice? = AVSpeechSynthesisVoice(language: "en-GB")
+    ) {
+        self.rateRatio = rateRatio
+        self.voice = voice
+        super.init()
+        self.speechSynthesizer.delegate = self
+        try? AVAudioSession.sharedInstance().setCategory(.playback)
+    }
+}
+
+extension Engine: AVSpeechSynthesizerDelegate {
+    public func speechSynthesizer(
+        _ synthesizer: AVSpeechSynthesizer,
+        didStart utterance: AVSpeechUtterance
+    ) {
+        self.speakingProgress = 0.0
+    }
+
+    public func speechSynthesizer(
+        _ synthesizer: AVSpeechSynthesizer,
+        didFinish utterance: AVSpeechUtterance
+    ) {
+        self.isSpeaking = false
+        self.speakingProgress = 1.0
+    }
+
+    public func speechSynthesizer(
+        _ synthesizer: AVSpeechSynthesizer,
+        willSpeakRangeOfSpeechString characterRange: NSRange,
+        utterance: AVSpeechUtterance
+    ) {
+        let total = Double(utterance.speechString.count)
+        let averageBound = [Double(characterRange.lowerBound), Double(characterRange.upperBound)]
+            .reduce(0, +)/2
+        self.speakingProgress = averageBound/total
+    }
+}
+
+extension Engine: TTSEngine {
+    public func speak(string: String) {
+        let speechUtterance = AVSpeechUtterance(string: string)
+        speechUtterance.voice = voice
+        speechUtterance.rate *= rateRatio
+        self.speechSynthesizer.speak(speechUtterance)
+        self.isSpeaking = true
+    }
+
+    public var isSpeakingPublisher: AnyPublisher<Bool, Never> {
+        $isSpeaking.eraseToAnyPublisher()
+    }
+
+    public var speakingProgressPublisher: AnyPublisher<Double, Never> {
+        $speakingProgress.eraseToAnyPublisher()
+    }
+}

Tests/LinuxMain.swift

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+import XCTest
+
+import SwiftTTSCombineTests
+
+var tests = [XCTestCaseEntry]()
+tests += SwiftTTSCombineTests.allTests()
+XCTMain(tests)

Tests/SwiftTTSCombineTests/SwiftTTSCombineTests.swift

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+import XCTest
+@testable import SwiftTTSCombine
+
+final class SwiftTTSCombineTests: XCTestCase {
+    func testExample() {
+        let engine = Engine()
+        engine.speak(string: "Hello World!")
+    }
+
+    static var allTests = [
+        ("testExample", testExample),
+    ]
+}

Tests/SwiftTTSCombineTests/XCTestManifests.swift

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+import XCTest
+
+#if !canImport(ObjectiveC)
+public func allTests() -> [XCTestCaseEntry] {
+    return [
+        testCase(SwiftTTSCombineTests.allTests),
+    ]
+}
+#endif