camera/camera-camera2-pipe-integration/src/main/java/androidx/camera/camera2/pipe/integration/impl/ComboRequestListener.kt

/*
 * Copyright 2021 The Android Open Source Project
 *
 * 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.
 */

package androidx.camera.camera2.pipe.integration.impl

import androidx.annotation.RequiresApi
import androidx.camera.camera2.pipe.CameraTimestamp
import androidx.camera.camera2.pipe.FrameInfo
import androidx.camera.camera2.pipe.FrameMetadata
import androidx.camera.camera2.pipe.FrameNumber
import androidx.camera.camera2.pipe.Request
import androidx.camera.camera2.pipe.RequestFailure
import androidx.camera.camera2.pipe.RequestMetadata
import androidx.camera.camera2.pipe.StreamId
import androidx.camera.camera2.pipe.integration.config.CameraScope
import androidx.camera.core.impl.TagBundle
import java.util.concurrent.Executor
import javax.inject.Inject

/**
 * A ComboRequestListener which contains a set of [Request.Listener]s.
 * The primary purpose of this class is to receive the capture result from the currently
 * configured [UseCaseCamera] and propagate to the registered [Request.Listener]s.
 */
@RequiresApi(21) // TODO(b/200306659): Remove and replace with annotation on package-info.java
@CameraScope
class ComboRequestListener @Inject constructor() : Request.Listener {
    private val requestListeners = mutableMapOf<Request.Listener, Executor>()

    @Volatile
    private var listeners: Map<Request.Listener, Executor> = mapOf()

    fun addListener(listener: Request.Listener, executor: Executor) {
        check(!listeners.contains(listener)) { "$listener was already registered!" }
        synchronized(requestListeners) {
            requestListeners[listener] = executor
            listeners = requestListeners.toMap()
        }
    }

    fun removeListener(listener: Request.Listener) {
        synchronized(requestListeners) {
            requestListeners.remove(listener)
            listeners = requestListeners.toMap()
        }
    }

    override fun onAborted(request: Request) {
        listeners.forEach { (listener, executor) ->
            executor.execute { listener.onAborted(request) }
        }
    }

    override fun onBufferLost(
        requestMetadata: RequestMetadata,
        frameNumber: FrameNumber,
        stream: StreamId
    ) {
        listeners.forEach { (listener, executor) ->
            executor.execute { listener.onBufferLost(requestMetadata, frameNumber, stream) }
        }
    }

    override fun onComplete(
        requestMetadata: RequestMetadata,
        frameNumber: FrameNumber,
        result: FrameInfo
    ) {
        listeners.forEach { (listener, executor) ->
            executor.execute { listener.onComplete(requestMetadata, frameNumber, result) }
        }
    }

    override fun onFailed(
        requestMetadata: RequestMetadata,
        frameNumber: FrameNumber,
        requestFailure: RequestFailure
    ) {
        listeners.forEach { (listener, executor) ->
            executor.execute {
                listener.onFailed(
                    requestMetadata,
                    frameNumber,
                    requestFailure
                )
            }
        }
    }

    override fun onPartialCaptureResult(
        requestMetadata: RequestMetadata,
        frameNumber: FrameNumber,
        captureResult: FrameMetadata
    ) {
        listeners.forEach { (listener, executor) ->
            executor.execute {
                listener.onPartialCaptureResult(
                    requestMetadata,
                    frameNumber,
                    captureResult
                )
            }
        }
    }

    override fun onRequestSequenceAborted(requestMetadata: RequestMetadata) {
        listeners.forEach { (listener, executor) ->
            executor.execute {
                listener.onRequestSequenceAborted(requestMetadata)
            }
        }
    }

    override fun onRequestSequenceCompleted(
        requestMetadata: RequestMetadata,
        frameNumber: FrameNumber
    ) {
        listeners.forEach { (listener, executor) ->
            executor.execute {
                listener.onRequestSequenceCompleted(requestMetadata, frameNumber)
            }
        }
    }

    override fun onRequestSequenceCreated(requestMetadata: RequestMetadata) {
        listeners.forEach { (listener, executor) ->
            executor.execute {
                listener.onRequestSequenceCreated(requestMetadata)
            }
        }
    }

    override fun onRequestSequenceSubmitted(requestMetadata: RequestMetadata) {
        listeners.forEach { (listener, executor) ->
            executor.execute {
                listener.onRequestSequenceSubmitted(requestMetadata)
            }
        }
    }

    override fun onStarted(
        requestMetadata: RequestMetadata,
        frameNumber: FrameNumber,
        timestamp: CameraTimestamp
    ) {
        listeners.forEach { (listener, executor) ->
            executor.execute {
                listener.onStarted(requestMetadata, frameNumber, timestamp)
            }
        }
    }

    override fun onTotalCaptureResult(
        requestMetadata: RequestMetadata,
        frameNumber: FrameNumber,
        totalCaptureResult: FrameInfo
    ) {
        listeners.forEach { (listener, executor) ->
            executor.execute {
                listener.onTotalCaptureResult(requestMetadata, frameNumber, totalCaptureResult)
            }
        }
    }
}

@RequiresApi(21) // TODO(b/200306659): Remove and replace with annotation on package-info.java
fun RequestMetadata.containsTag(tagKey: String, tagValue: Any): Boolean =
    getOrDefault(
        CAMERAX_TAG_BUNDLE,
        TagBundle.emptyBundle()
    ).getTag(tagKey).let {
        return it == tagValue
    }