import AVFoundation
import XCTest

@testable import CallsKit

/// The Mic Mode row is only shown on iPhone, but what it says is plain
/// logic over two values, and it is held here with a stand-in for
/// AVCaptureDevice, whose modes a test cannot set.
@MainActor final class MicrophoneModeTests: XCTestCase {
  final class FakeModes: MicrophoneModeSource {
    var preferred: AVCaptureDevice.MicrophoneMode = .standard
    var active: AVCaptureDevice.MicrophoneMode = .standard
    var changed: (@Sendable () -> Void)?
    var pickerShown = 0
    func showPicker() { pickerShown += 1 }
  }

  func testTheModesAreCalledWhatControlCenterCallsThem() {
    XCTAssertEqual(MicrophoneModes.name(.standard), "Standard")
    XCTAssertEqual(MicrophoneModes.name(.voiceIsolation), "Voice Isolation")
    XCTAssertEqual(MicrophoneModes.name(.wideSpectrum), "Wide Spectrum")
  }

  func testAnOverriddenChoiceNamesBothAndLeadsWithTheTruth() {
    // Saying "Voice Isolation" while the route runs Standard would be a
    // claim about audio the call is not getting.
    XCTAssertEqual(MicrophoneModes.summary(preferred: .voiceIsolation, active: .voiceIsolation), "Voice Isolation")
    let overridden = MicrophoneModes.summary(preferred: .voiceIsolation, active: .standard)
    XCTAssertTrue(overridden.hasPrefix("Standard"), overridden)
    XCTAssertTrue(overridden.contains("Voice Isolation is chosen"), overridden)
  }

  func testTheRowFollowsTheSystemWhenItSaysSomethingChanged() async {
    let fake = FakeModes()
    let modes = MicrophoneModes(source: fake)
    XCTAssertEqual(modes.summary, "Standard")

    fake.preferred = .voiceIsolation
    fake.active = .voiceIsolation
    fake.changed?()
    // The change is delivered through a main-actor hop, as a KVO callback
    // from any thread would be.
    for _ in 0..<10 where modes.active != .voiceIsolation { await Task.yield() }
    XCTAssertEqual(modes.preferred, .voiceIsolation)
    XCTAssertEqual(modes.summary, "Voice Isolation")
  }

  func testChangingTheModeIsTheSystemPickersJob() {
    // There is no setter to call: the button only opens Apple's picker.
    let fake = FakeModes()
    let modes = MicrophoneModes(source: fake)
    modes.showPicker()
    XCTAssertEqual(fake.pickerShown, 1)
    XCTAssertEqual(modes.active, .standard)
  }
}