import { combineLatest, firstValueFrom, Observable } from 'rxjs';
import type { INoiseCancellation } from '@stream-io/audio-filters-web';
import { Call } from '../Call';
import {
  AudioDeviceManager,
  createAudioConstraints,
} from './AudioDeviceManager';
import { type BrowserPermissionState } from './BrowserPermission';
import { MicrophoneManagerState } from './MicrophoneManagerState';
import { TrackDisableMode } from './DeviceManagerState';
import { getAudioDevices, getAudioStream } from './devices';
import { AudioBitrateProfile, TrackType } from '../gen/video/sfu/models/models';
import { createSoundDetector } from '../helpers/sound-detector';
import { createNoAudioDetector } from '../helpers/no-audio-detector';
import { isReactNative } from '../helpers/platforms';
import {
  AudioSettingsResponse,
  NoiseCancellationSettingsModeEnum,
  OwnCapability,
} from '../gen/coordinator';
import { type MicCaptureReportEvent } from '../coordinator/connection/types';
import { CallingState } from '../store';
import {
  createSafeAsyncSubscription,
  createSubscription,
} from '../store/rxUtils';
import { withoutConcurrency } from '../helpers/concurrency';
import { disposeOfMediaStream } from './utils';
import { promiseWithResolvers } from '../helpers/promise';
import { DevicePersistenceOptions } from './devicePersistence';

export class MicrophoneManager extends AudioDeviceManager<MicrophoneManagerState> {
  private speakingWhileMutedNotificationEnabled = true;
  private soundDetectorConcurrencyTag = Symbol('soundDetectorConcurrencyTag');
  private soundDetectorCleanup?: () => Promise<void>;
  private soundDetectorDeviceId?: string;
  private noAudioDetectorCleanup?: () => Promise<void>;
  private noiseCancellation: INoiseCancellation | undefined;
  private noiseCancellationChangeUnsubscribe: (() => void) | undefined;
  private noiseCancellationRegistration?: Promise<void>;
  private unregisterNoiseCancellation?: () => Promise<void>;

  private silenceThresholdMs = 5000;

  constructor(
    call: Call,
    devicePersistence: Required<DevicePersistenceOptions>,
    disableMode: TrackDisableMode = 'stop-tracks',
  ) {
    super(
      call,
      new MicrophoneManagerState(disableMode, call.tracer),
      TrackType.AUDIO,
      devicePersistence,
    );
  }

  override setup(): void {
    if (this.areSubscriptionsSetUp) return;
    super.setup();
    this.subscriptions.push(
      createSafeAsyncSubscription(
        combineLatest([
          this.call.state.callingState$,
          this.call.state.ownCapabilities$,
          this.state.selectedDevice$,
          this.state.status$,
          this.state.browserPermissionState$,
        ]),
        async ([
          callingState,
          ownCapabilities,
          deviceId,
          status,
          permissionState,
        ]) => {
          try {
            if (callingState === CallingState.LEFT) {
              await this.stopSpeakingWhileMutedDetection();
            }
            if (callingState !== CallingState.JOINED) return;
            if (!this.speakingWhileMutedNotificationEnabled) return;

            if (ownCapabilities.includes(OwnCapability.SEND_AUDIO)) {
              const hasPermission = await this.hasPermission(permissionState);
              if (hasPermission && status !== 'enabled') {
                await this.startSpeakingWhileMutedDetection(deviceId);
              } else {
                await this.stopSpeakingWhileMutedDetection();
              }
            } else {
              await this.stopSpeakingWhileMutedDetection();
            }
          } catch (err) {
            this.logger.warn('Could not enable speaking while muted', err);
          }
        },
      ),
    );

    this.subscriptions.push(
      createSubscription(this.call.state.callingState$, (callingState) => {
        // do nothing when noise filtering isn't turned on
        if (!this.noiseCancellationRegistration || !this.noiseCancellation)
          return;

        const autoOn =
          this.call.state.settings?.audio.noise_cancellation?.mode ===
          NoiseCancellationSettingsModeEnum.AUTO_ON;

        if (autoOn && callingState === CallingState.JOINED) {
          this.noiseCancellationRegistration
            .then(() => {
              if (this.noiseCancellation?.canAutoEnable) {
                return this.noiseCancellation.canAutoEnable();
              }
              return true;
            })
            .then((canAutoEnable) => {
              if (canAutoEnable) {
                this.noiseCancellation?.enable().catch((err) => {
                  this.logger.warn('Failed to enable noise cancellation', err);
                });
              }
            })
            .catch((err) => {
              this.logger.warn(`Failed to enable noise cancellation`, err);
              return this.call.notifyNoiseCancellationStopped();
            });
        } else if (callingState === CallingState.LEFT) {
          this.noiseCancellationRegistration
            .then(() => this.noiseCancellation?.disable())
            .catch((err) => {
              this.logger.warn(`Failed to disable noise cancellation`, err);
            });
        }
      }),
    );

    if (!isReactNative()) {
      const unsubscribe = createSafeAsyncSubscription(
        combineLatest([this.state.status$, this.state.mediaStream$]),
        async ([status, mediaStream]) => {
          if (this.noAudioDetectorCleanup) {
            const cleanup = this.noAudioDetectorCleanup;
            this.noAudioDetectorCleanup = undefined;
            await cleanup().catch((err) => {
              this.logger.warn('Failed to stop no-audio detector', err);
            });
          }

          if (status !== 'enabled' || !mediaStream) return;
          if (this.silenceThresholdMs <= 0) return;

          const deviceId = this.state.selectedDevice;
          const devices = await firstValueFrom(this.listDevices());
          const label = devices.find((d) => d.deviceId === deviceId)?.label;

          let lastCapturesAudio: boolean | undefined;
          this.noAudioDetectorCleanup = createNoAudioDetector(mediaStream, {
            noAudioThresholdMs: this.silenceThresholdMs,
            emitIntervalMs: this.silenceThresholdMs,
            onCaptureStatusChange: (capturesAudio) => {
              const event: MicCaptureReportEvent = {
                type: 'mic.capture_report',
                call_cid: this.call.cid,
                capturesAudio,
                deviceId,
                label,
              };

              if (capturesAudio !== lastCapturesAudio) {
                lastCapturesAudio = capturesAudio;
                this.call.tracer.trace('mic.capture_report', event);
              }

              this.call.streamClient.dispatchEvent(event);
            },
          });
        },
      );
      this.subscriptions.push(unsubscribe);
    }
  }

  /**
   * Enables noise cancellation for the microphone.
   *
   * @param noiseCancellation - a noise cancellation instance to use.
   */
  async enableNoiseCancellation(noiseCancellation: INoiseCancellation) {
    const { ownCapabilities, settings } = this.call.state;
    const hasNoiseCancellationCapability = ownCapabilities.includes(
      OwnCapability.ENABLE_NOISE_CANCELLATION,
    );
    if (!hasNoiseCancellationCapability) {
      throw new Error('Noise cancellation is not available.');
    }
    const noiseCancellationSettings = settings?.audio.noise_cancellation;
    if (
      !noiseCancellationSettings ||
      noiseCancellationSettings.mode ===
        NoiseCancellationSettingsModeEnum.DISABLED
    ) {
      throw new Error('Noise cancellation is disabled for this call type.');
    }
    try {
      this.noiseCancellation = noiseCancellation;

      // listen for change events and notify the SFU
      this.noiseCancellationChangeUnsubscribe = this.noiseCancellation.on(
        'change',
        (enabled: boolean) => {
          this.call.tracer.trace('noiseCancellation.enabled', enabled);
          if (enabled) {
            this.call.notifyNoiseCancellationStarting().catch((err) => {
              this.logger.warn(`notifyNoiseCancellationStart failed`, err);
            });
          } else {
            this.call.notifyNoiseCancellationStopped().catch((err) => {
              this.logger.warn(`notifyNoiseCancellationStop failed`, err);
            });
          }
        },
      );

      if (isReactNative()) {
        // no filter registration in React Native, its done in the native code on app init
        this.noiseCancellationRegistration = Promise.resolve();
      } else {
        const registrationResult = this.registerFilter(
          noiseCancellation.toFilter(),
        );
        this.noiseCancellationRegistration = registrationResult.registered;
        this.unregisterNoiseCancellation = registrationResult.unregister;
        await this.noiseCancellationRegistration;
      }

      // handles an edge case where a noise cancellation is enabled after
      // the participant as joined the call -> we immediately enable NC
      if (
        noiseCancellationSettings.mode ===
          NoiseCancellationSettingsModeEnum.AUTO_ON &&
        this.call.state.callingState === CallingState.JOINED
      ) {
        let canAutoEnable = true;
        if (noiseCancellation.canAutoEnable) {
          canAutoEnable = await noiseCancellation.canAutoEnable();
        }
        if (canAutoEnable) {
          noiseCancellation.enable().catch((err) => {
            this.logger.warn('Failed to enable noise cancellation', err);
          });
        }
      }
    } catch (e) {
      this.logger.warn('Failed to enable noise cancellation', e);
      await this.disableNoiseCancellation().catch((err) => {
        this.logger.warn('Failed to disable noise cancellation', err);
      });
      throw e;
    }
  }

  /**
   * Disables noise cancellation for the microphone.
   */
  async disableNoiseCancellation() {
    await (this.unregisterNoiseCancellation?.() ?? Promise.resolve())
      .then(() => this.noiseCancellation?.disable())
      .then(() => this.noiseCancellationChangeUnsubscribe?.())
      .catch((err) => {
        this.logger.warn('Failed to unregister noise cancellation', err);
      });

    this.call.tracer.trace('noiseCancellation.disabled', true);
    await this.call.notifyNoiseCancellationStopped();
  }

  /**
   * Enables speaking while muted notification.
   */
  async enableSpeakingWhileMutedNotification() {
    this.speakingWhileMutedNotificationEnabled = true;
    if (this.state.status === 'disabled') {
      await this.startSpeakingWhileMutedDetection(this.state.selectedDevice);
    }
  }

  /**
   * Disables speaking while muted notification.
   */
  async disableSpeakingWhileMutedNotification() {
    this.speakingWhileMutedNotificationEnabled = false;
    await this.stopSpeakingWhileMutedDetection();
  }

  /**
   * Sets the silence threshold in milliseconds for no-audio detection.
   * When the microphone is enabled but produces no audio for this duration,
   * a 'mic.capture_report' event will be emitted.
   *
   * @param thresholdMs the threshold in milliseconds (default: 5000).
   *   Set to 0 or a negative value to disable no-audio detection.
   */
  setSilenceThreshold(thresholdMs: number) {
    this.silenceThresholdMs = thresholdMs;
  }

  /**
   * Performs audio capture test on a specific microphone.
   *
   * This method is only available in browser environments (not React Native).
   *
   * @param deviceId The device ID to test.
   * @param options Optional test configuration.
   * @returns Promise that resolves with the test result (true or false).
   */
  async performTest(
    deviceId: string,
    options?: { testDurationMs?: number },
  ): Promise<boolean> {
    if (isReactNative()) throw new Error('Not available in React Native');

    const stream = await this.getStream({ deviceId: { exact: deviceId } });
    const { testDurationMs = 3000 } = options || {};
    const { promise, resolve } = promiseWithResolvers<boolean>();
    const cleanup = createNoAudioDetector(stream, {
      noAudioThresholdMs: testDurationMs,
      emitIntervalMs: testDurationMs,
      onCaptureStatusChange: async (capturesAudio) => {
        resolve(capturesAudio);
        await cleanup().catch((err) => {
          this.logger.warn('Failed to stop detector during test', err);
        });
        disposeOfMediaStream(stream);
      },
    });
    return promise;
  }

  /**
   * Applies the audio settings to the microphone.
   * @param settings the audio settings to apply.
   * @param publish whether to publish the stream after applying the settings.
   */
  async apply(settings: AudioSettingsResponse, publish: boolean) {
    // Wait for any in progress mic operation
    await this.statusChangeSettled();

    // apply server-side settings only when the device state is pristine
    // and there are no persisted preferences
    const shouldApplyDefaults =
      this.state.status === undefined &&
      this.state.optimisticStatus === undefined;
    let persistedPreferencesApplied = false;
    const permissionState = await firstValueFrom(
      this.state.browserPermissionState$,
    );
    if (
      shouldApplyDefaults &&
      this.devicePersistence.enabled &&
      permissionState === 'granted'
    ) {
      persistedPreferencesApplied = await this.applyPersistedPreferences(true);
    }

    const canPublish = this.call.permissionsContext.canPublish(this.trackType);
    if (shouldApplyDefaults && !persistedPreferencesApplied) {
      if (canPublish && settings.mic_default_on) {
        await this.enable();
      }
    }

    const { mediaStream } = this.state;
    if (canPublish && publish && this.enabled && mediaStream) {
      await this.publishStream(mediaStream);
    }
  }

  protected override getDevices(): Observable<MediaDeviceInfo[]> {
    return getAudioDevices(this.call.tracer);
  }

  protected override getStream(
    constraints: MediaTrackConstraints,
  ): Promise<MediaStream> {
    return getAudioStream(constraints, this.call.tracer);
  }

  protected override doSetAudioBitrateProfile(profile: AudioBitrateProfile) {
    this.setDefaultConstraints({
      ...this.state.defaultConstraints,
      ...createAudioConstraints(profile),
    });

    if (this.noiseCancellation) {
      const disableAudioProcessing =
        profile === AudioBitrateProfile.MUSIC_HIGH_QUALITY;
      if (disableAudioProcessing) {
        this.noiseCancellation.disable().catch((err) => {
          this.logger.warn(
            'Failed to disable noise cancellation for music mode',
            err,
          );
        }); // disable for high quality music mode
      } else {
        this.noiseCancellation.enable().catch((err) => {
          this.logger.warn('Failed to enable noise cancellation', err);
        }); // restore it for other modes if available
      }
    }
  }

  private async startSpeakingWhileMutedDetection(deviceId?: string) {
    await withoutConcurrency(this.soundDetectorConcurrencyTag, async () => {
      if (this.soundDetectorCleanup && this.soundDetectorDeviceId === deviceId)
        return;

      await this.teardownSpeakingWhileMutedDetection();

      if (isReactNative()) {
        const speechActivity =
          globalThis.streamRNVideoSDK?.nativeEvents?.speechActivity;
        if (!speechActivity) {
          this.logger.warn(
            'Native speech activity not available, make sure the "@stream-io/react-native-webrtc" peer dependency version is satisfied',
          );
          return;
        }
        const unsubscribe = speechActivity.subscribe((event) => {
          this.state.setSpeakingWhileMuted(event.isSoundDetected);
        });
        this.soundDetectorCleanup = async () => {
          unsubscribe();
        };
      } else {
        // Need to start a new stream that's not connected to publisher
        const stream = await this.getStream({
          ...this.state.defaultConstraints,
          deviceId: { exact: deviceId },
        });
        this.soundDetectorCleanup = createSoundDetector(stream, (event) => {
          this.state.setSpeakingWhileMuted(event.isSoundDetected);
        });
      }

      this.soundDetectorDeviceId = deviceId;
    });
  }

  private async stopSpeakingWhileMutedDetection() {
    await withoutConcurrency(this.soundDetectorConcurrencyTag, async () => {
      return this.teardownSpeakingWhileMutedDetection();
    });
  }

  private async teardownSpeakingWhileMutedDetection(): Promise<void> {
    const soundDetectorCleanup = this.soundDetectorCleanup;
    this.soundDetectorCleanup = undefined;
    this.soundDetectorDeviceId = undefined;
    this.state.setSpeakingWhileMuted(false);
    if (!soundDetectorCleanup) return;

    await soundDetectorCleanup().catch((err) => {
      this.logger.warn('Failed to stop speaking while muted detector', err);
    });
  }

  private async hasPermission(
    permissionState: BrowserPermissionState,
  ): Promise<boolean> {
    if (!isReactNative()) return permissionState === 'granted';

    const nativePermissions = globalThis.streamRNVideoSDK?.permissions;
    if (!nativePermissions) return true; // assume granted

    try {
      return await nativePermissions.check('microphone');
    } catch (err) {
      this.logger.warn('Failed to check permission', err);
      return false;
    }
  }
}