/*
 * Copyright (C) 2018 Square, Inc.
 *
 * 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 shark

import java.util.EnumSet
import kotlin.math.absoluteValue
import shark.AndroidObjectInspectors.Companion.appDefaults
import shark.AndroidServices.aliveAndroidServiceObjectIds
import shark.FilteringLeakingObjectFinder.LeakingObjectFilter
import shark.HeapObject.HeapInstance
import shark.internal.InternalSharkCollectionsHelper

/**
 * A set of default [ObjectInspector]s that knows about common AOSP and library
 * classes.
 *
 * These are heuristics based on our experience and knowledge of AOSP and various library
 * internals. We only make a decision if we're reasonably sure the state of an object is
 * unlikely to be the result of a programmer mistake.
 *
 * For example, no matter how many mistakes we make in our code, the value of Activity.mDestroy
 * will not be influenced by those mistakes.
 *
 * Most developers should use the entire set of default [ObjectInspector] by calling [appDefaults],
 * unless there's a bug and you temporarily want to remove an inspector.
 */
enum class AndroidObjectInspectors : ObjectInspector {

  VIEW {
    override val leakingObjectFilter = { heapObject: HeapObject ->
      if (heapObject is HeapInstance && heapObject instanceOf "android.view.View") {
        // Leaking if null parent or non view parent.
        val viewParent = heapObject["android.view.View", "mParent"]!!.valueAsInstance
        val isParentlessView = viewParent == null
        val isChildOfViewRootImpl =
          viewParent != null && !(viewParent instanceOf "android.view.View")
        val isRootView = isParentlessView || isChildOfViewRootImpl

        // This filter only cares for root view because we only need one view in a view hierarchy.
        if (isRootView) {
          val mContext = heapObject["android.view.View", "mContext"]!!.value.asObject!!.asInstance!!
          val activityContext = mContext.unwrapActivityContext()
          val mContextIsDestroyedActivity = (activityContext != null &&
            activityContext["android.app.Activity", "mDestroyed"]?.value?.asBoolean == true)
          if (mContextIsDestroyedActivity) {
            // Root view with unwrapped mContext a destroyed activity.
            true
          } else {
            val viewDetached =
              heapObject["android.view.View", "mAttachInfo"]!!.value.isNullReference
            if (viewDetached) {
              val mWindowAttachCount =
                heapObject["android.view.View", "mWindowAttachCount"]?.value!!.asInt!!
              if (mWindowAttachCount > 0) {
                when {
                  isChildOfViewRootImpl -> {
                    // Child of ViewRootImpl that was once attached and is now detached.
                    // Unwrapped mContext not a destroyed activity. This could be a dialog root.
                    true
                  }
                  heapObject.instanceClassName == "com.android.internal.policy.DecorView" -> {
                    // DecorView with null parent, once attached now detached.
                    // Unwrapped mContext not a destroyed activity. This could be a dialog root.
                    // Unlikely to be a reusable cached view => leak.
                    true
                  }
                  else -> {
                    // View with null parent, once attached now detached.
                    // Unwrapped mContext not a destroyed activity. This could be a dialog root.
                    // Could be a leak or could be a reusable cached view.
                    false
                  }
                }
              } else {
                // Root view, detached but was never attached.
                // This could be a cached instance.
                false
              }
            } else {
              // Root view that is attached.
              false
            }
          }
        } else {
          // Not a root view.
          false
        }
      } else {
        // Not a view
        false
      }
    }

    override fun inspect(
      reporter: ObjectReporter
    ) {
      reporter.whenInstanceOf("android.view.View") { instance ->
        // This skips edge cases like Toast$TN.mNextView holding on to an unattached and unparented
        // next toast view
        var rootParent = instance["android.view.View", "mParent"]!!.valueAsInstance
        var rootView: HeapInstance? = null
        while (rootParent != null && rootParent instanceOf "android.view.View") {
          rootView = rootParent
          rootParent = rootParent["android.view.View", "mParent"]!!.valueAsInstance
        }

        val partOfWindowHierarchy = rootParent != null || (rootView != null &&
          rootView.instanceClassName == "com.android.internal.policy.DecorView")

        val mWindowAttachCount =
          instance["android.view.View", "mWindowAttachCount"]?.value!!.asInt!!
        val viewDetached = instance["android.view.View", "mAttachInfo"]!!.value.isNullReference
        val mContext = instance["android.view.View", "mContext"]!!.value.asObject!!.asInstance!!

        val activityContext = mContext.unwrapActivityContext()
        if (activityContext != null && activityContext["android.app.Activity", "mDestroyed"]?.value?.asBoolean == true) {
          leakingReasons += "View.mContext references a destroyed activity"
        } else {
          if (partOfWindowHierarchy && mWindowAttachCount > 0) {
            if (viewDetached) {
              leakingReasons += "View detached yet still part of window view hierarchy"
            } else {
              if (rootView != null && rootView["android.view.View", "mAttachInfo"]!!.value.isNullReference) {
                leakingReasons += "View attached but root view ${rootView.instanceClassName} detached (attach disorder)"
              } else {
                notLeakingReasons += "View attached"
              }
            }
          }
        }

        labels += if (partOfWindowHierarchy) {
          "View is part of a window view hierarchy"
        } else {
          "View not part of a window view hierarchy"
        }

        labels += if (viewDetached) {
          "View.mAttachInfo is null (view detached)"
        } else {
          "View.mAttachInfo is not null (view attached)"
        }

        AndroidResourceIdNames.readFromHeap(instance.graph)
          ?.let { resIds ->
            val mID = instance["android.view.View", "mID"]!!.value.asInt!!
            val noViewId = -1
            if (mID != noViewId) {
              val resourceName = resIds[mID]
              labels += "View.mID = R.id.$resourceName"
            }
          }
        labels += "View.mWindowAttachCount = $mWindowAttachCount"
      }
    }
  },

  EDITOR {
    override val leakingObjectFilter = { heapObject: HeapObject ->
      heapObject is HeapInstance &&
        heapObject instanceOf "android.widget.Editor" &&
        heapObject["android.widget.Editor", "mTextView"]?.value?.asObject?.let { textView ->
          VIEW.leakingObjectFilter!!(textView)
        } ?: false
    }

    override fun inspect(reporter: ObjectReporter) {
      reporter.whenInstanceOf("android.widget.Editor") { instance ->
        applyFromField(VIEW, instance["android.widget.Editor", "mTextView"])
      }
    }
  },

  ACTIVITY {
    override val leakingObjectFilter = { heapObject: HeapObject ->
      heapObject is HeapInstance &&
        heapObject instanceOf "android.app.Activity" &&
        heapObject["android.app.Activity", "mDestroyed"]?.value?.asBoolean == true
    }

    override fun inspect(
      reporter: ObjectReporter
    ) {
      reporter.whenInstanceOf("android.app.Activity") { instance ->
        // Activity.mDestroyed was introduced in 17.
        // https://android.googlesource.com/platform/frameworks/base/+
        // /6d9dcbccec126d9b87ab6587e686e28b87e5a04d
        val field = instance["android.app.Activity", "mDestroyed"]

        if (field != null) {
          if (field.value.asBoolean!!) {
            leakingReasons += field describedWithValue "true"
          } else {
            notLeakingReasons += field describedWithValue "false"
          }
        }
      }
    }
  },

  SERVICE {
    override val leakingObjectFilter = { heapObject: HeapObject ->
      heapObject is HeapInstance &&
        heapObject instanceOf "android.app.Service" &&
        heapObject.objectId !in heapObject.graph.aliveAndroidServiceObjectIds
    }

    override fun inspect(
      reporter: ObjectReporter
    ) {
      reporter.whenInstanceOf("android.app.Service") { instance ->
        if (instance.objectId in instance.graph.aliveAndroidServiceObjectIds) {
          notLeakingReasons += "Service held by ActivityThread"
        } else {
          leakingReasons += "Service not held by ActivityThread"
        }
      }
    }
  },

  CONTEXT_FIELD {
    override fun inspect(reporter: ObjectReporter) {
      val instance = reporter.heapObject
      if (instance !is HeapInstance) {
        return
      }
      instance.readFields().forEach { field ->
        val fieldInstance = field.valueAsInstance
        if (fieldInstance != null && fieldInstance instanceOf "android.content.Context") {
          reporter.run {
            val componentContext = fieldInstance.unwrapComponentContext()
            labels += if (componentContext == null) {
              "${field.name} instance of ${fieldInstance.instanceClassName}"
            } else if (componentContext instanceOf "android.app.Activity") {
              val activityDescription =
                "with mDestroyed = " + (componentContext["android.app.Activity", "mDestroyed"]?.value?.asBoolean?.toString()
                  ?: "UNKNOWN")
              if (componentContext == fieldInstance) {
                "${field.name} instance of ${fieldInstance.instanceClassName} $activityDescription"
              } else {
                "${field.name} instance of ${fieldInstance.instanceClassName}, " +
                  "wrapping activity ${componentContext.instanceClassName} $activityDescription"
              }
            } else if (componentContext == fieldInstance) {
              // No need to add "instance of Application / Service", devs know their own classes.
              "${field.name} instance of ${fieldInstance.instanceClassName}"
            } else {
              "${field.name} instance of ${fieldInstance.instanceClassName}, wrapping ${componentContext.instanceClassName}"
            }
          }
        }
      }
    }
  },

  CONTEXT_WRAPPER {

    override val leakingObjectFilter = { heapObject: HeapObject ->
      heapObject is HeapInstance &&
        heapObject.unwrapActivityContext()
          ?.get("android.app.Activity", "mDestroyed")?.value?.asBoolean == true
    }

    override fun inspect(
      reporter: ObjectReporter
    ) {
      val instance = reporter.heapObject
      if (instance !is HeapInstance) {
        return
      }

      // We're looking for ContextWrapper instances that are not Activity, Application or Service.
      // So we stop whenever we find any of those 4 classes, and then only keep ContextWrapper.
      val matchingClassName = instance.instanceClass.classHierarchy.map { it.name }
        .firstOrNull {
          when (it) {
            "android.content.ContextWrapper",
            "android.app.Activity",
            "android.app.Application",
            "android.app.Service"
            -> true
            else -> false
          }
        }

      if (matchingClassName == "android.content.ContextWrapper") {
        reporter.run {
          val componentContext = instance.unwrapComponentContext()
          if (componentContext != null) {
            if (componentContext instanceOf "android.app.Activity") {
              val mDestroyed = componentContext["android.app.Activity", "mDestroyed"]
              if (mDestroyed != null) {
                if (mDestroyed.value.asBoolean!!) {
                  leakingReasons += "${instance.instanceClassSimpleName} wraps an Activity with Activity.mDestroyed true"
                } else {
                  // We can't assume it's not leaking, because this context might have a shorter lifecycle
                  // than the activity. So we'll just add a label.
                  labels += "${instance.instanceClassSimpleName} wraps an Activity with Activity.mDestroyed false"
                }
              }
            } else if (componentContext instanceOf "android.app.Application") {
              labels += "${instance.instanceClassSimpleName} wraps an Application context"
            } else {
              labels += "${instance.instanceClassSimpleName} wraps a Service context"
            }
          } else {
            labels += "${instance.instanceClassSimpleName} does not wrap a known Android context"
          }
        }
      }
    }
  },

  APPLICATION_PACKAGE_MANAGER {
    override val leakingObjectFilter = { heapObject: HeapObject ->
      heapObject is HeapInstance &&
        heapObject instanceOf "android.app.ApplicationContextManager" &&
        heapObject["android.app.ApplicationContextManager", "mContext"]!!
          .valueAsInstance!!.outerContextIsLeaking()
    }

    override fun inspect(reporter: ObjectReporter) {
      reporter.whenInstanceOf("android.app.ApplicationContextManager") { instance ->
        val outerContext = instance["android.app.ApplicationContextManager", "mContext"]!!
          .valueAsInstance!!["android.app.ContextImpl", "mOuterContext"]!!
          .valueAsInstance!!
        inspectContextImplOuterContext(outerContext, instance, "ApplicationContextManager.mContext")
      }
    }
  },

  CONTEXT_IMPL {
    override val leakingObjectFilter = { heapObject: HeapObject ->
      heapObject is HeapInstance &&
        heapObject instanceOf "android.app.ContextImpl" &&
        heapObject.outerContextIsLeaking()
    }

    override fun inspect(reporter: ObjectReporter) {
      reporter.whenInstanceOf("android.app.ContextImpl") { instance ->
        val outerContext = instance["android.app.ContextImpl", "mOuterContext"]!!
          .valueAsInstance!!
        inspectContextImplOuterContext(outerContext, instance)
      }
    }
  },

  DIALOG {
    override fun inspect(
      reporter: ObjectReporter
    ) {
      reporter.whenInstanceOf("android.app.Dialog") { instance ->
        val mDecor = instance["android.app.Dialog", "mDecor"]!!
        // Can't infer leaking status: mDecor null means either never shown or dismiss.
        // mDecor non null means the dialog is showing, but sometimes dialogs stay showing
        // after activity destroyed so that's not really a non leak either.
        labels += mDecor describedWithValue if (mDecor.value.isNullReference) {
          "null"
        } else {
          "not null"
        }
      }
    }
  },

  ACTIVITY_THREAD {
    override fun inspect(reporter: ObjectReporter) {
      reporter.whenInstanceOf("android.app.ActivityThread") {
        notLeakingReasons += "ActivityThread is a singleton"
      }
    }
  },

  APPLICATION {
    override fun inspect(
      reporter: ObjectReporter
    ) {
      reporter.whenInstanceOf("android.app.Application") {
        notLeakingReasons += "Application is a singleton"
      }
    }
  },

  INPUT_METHOD_MANAGER {
    override fun inspect(
      reporter: ObjectReporter
    ) {
      reporter.whenInstanceOf("android.view.inputmethod.InputMethodManager") {
        notLeakingReasons += "InputMethodManager is a singleton"
      }
    }
  },

  FRAGMENT {
    override val leakingObjectFilter = { heapObject: HeapObject ->
      heapObject is HeapInstance &&
        heapObject instanceOf "android.app.Fragment" &&
        heapObject["android.app.Fragment", "mFragmentManager"]!!.value.isNullReference
    }

    override fun inspect(
      reporter: ObjectReporter
    ) {
      reporter.whenInstanceOf("android.app.Fragment") { instance ->
        val fragmentManager = instance["android.app.Fragment", "mFragmentManager"]!!
        if (fragmentManager.value.isNullReference) {
          leakingReasons += fragmentManager describedWithValue "null"
        } else {
          notLeakingReasons += fragmentManager describedWithValue "not null"
        }
        val mTag = instance["android.app.Fragment", "mTag"]?.value?.readAsJavaString()
        if (!mTag.isNullOrEmpty()) {
          labels += "Fragment.mTag=$mTag"
        }
      }
    }
  },

  SUPPORT_FRAGMENT {

    override val leakingObjectFilter = { heapObject: HeapObject ->
      heapObject is HeapInstance &&
        heapObject instanceOf ANDROID_SUPPORT_FRAGMENT_CLASS_NAME &&
        heapObject.getOrThrow(
          ANDROID_SUPPORT_FRAGMENT_CLASS_NAME, "mFragmentManager"
        ).value.isNullReference
    }

    override fun inspect(
      reporter: ObjectReporter
    ) {
      reporter.whenInstanceOf(ANDROID_SUPPORT_FRAGMENT_CLASS_NAME) { instance ->
        val fragmentManager =
          instance.getOrThrow(ANDROID_SUPPORT_FRAGMENT_CLASS_NAME, "mFragmentManager")
        if (fragmentManager.value.isNullReference) {
          leakingReasons += fragmentManager describedWithValue "null"
        } else {
          notLeakingReasons += fragmentManager describedWithValue "not null"
        }
        val mTag = instance[ANDROID_SUPPORT_FRAGMENT_CLASS_NAME, "mTag"]?.value?.readAsJavaString()
        if (!mTag.isNullOrEmpty()) {
          labels += "Fragment.mTag=$mTag"
        }
      }
    }
  },

  ANDROIDX_FRAGMENT {
    override val leakingObjectFilter = { heapObject: HeapObject ->
      heapObject is HeapInstance &&
        heapObject instanceOf "androidx.fragment.app.Fragment" &&
        heapObject["androidx.fragment.app.Fragment", "mLifecycleRegistry"]!!
          .valueAsInstance
          ?.lifecycleRegistryState == "DESTROYED"
    }

    override fun inspect(
      reporter: ObjectReporter
    ) {
      reporter.whenInstanceOf("androidx.fragment.app.Fragment") { instance ->
        val lifecycleRegistryField = instance["androidx.fragment.app.Fragment", "mLifecycleRegistry"]!!
        val lifecycleRegistry = lifecycleRegistryField.valueAsInstance
        if (lifecycleRegistry != null) {
          val state = lifecycleRegistry.lifecycleRegistryState
          val reason = "Fragment.mLifecycleRegistry.state is $state"
          if (state == "DESTROYED") {
            leakingReasons += reason
          } else {
            notLeakingReasons += reason
          }
        } else {
          labels += "Fragment.mLifecycleRegistry = null"
        }
        val mTag = instance["androidx.fragment.app.Fragment", "mTag"]?.value?.readAsJavaString()
        if (!mTag.isNullOrEmpty()) {
          labels += "Fragment.mTag = $mTag"
        }
      }
    }
  },

  MESSAGE_QUEUE {
    override val leakingObjectFilter = { heapObject: HeapObject ->
      heapObject is HeapInstance &&
        heapObject instanceOf "android.os.MessageQueue" &&
        (heapObject["android.os.MessageQueue", "mQuitting"]
          ?: heapObject["android.os.MessageQueue", "mQuiting"]!!).value.asBoolean!!
    }

    override fun inspect(
      reporter: ObjectReporter
    ) {
      reporter.whenInstanceOf("android.os.MessageQueue") { instance ->
        // mQuiting had a typo and was renamed to mQuitting
        // https://android.googlesource.com/platform/frameworks/base/+/013cf847bcfd2828d34dced60adf2d3dd98021dc
        val mQuitting = instance["android.os.MessageQueue", "mQuitting"]
          ?: instance["android.os.MessageQueue", "mQuiting"]!!
        if (mQuitting.value.asBoolean!!) {
          leakingReasons += mQuitting describedWithValue "true"
        } else {
          notLeakingReasons += mQuitting describedWithValue "false"
        }

        val queueHead = instance["android.os.MessageQueue", "mMessages"]!!.valueAsInstance
        if (queueHead != null) {
          val targetHandler = queueHead["android.os.Message", "target"]!!.valueAsInstance
          if (targetHandler != null) {
            val looper = targetHandler["android.os.Handler", "mLooper"]!!.valueAsInstance
            if (looper != null) {
              val thread = looper["android.os.Looper", "mThread"]!!.valueAsInstance!!
              val threadName = thread[Thread::class, "name"]!!.value.readAsJavaString()
              labels += "HandlerThread: \"$threadName\""
            }
          }
        }
      }
    }
  },

  LOADED_APK {
    override fun inspect(
      reporter: ObjectReporter
    ) {
      reporter.whenInstanceOf("android.app.LoadedApk") { instance ->
        val receiversMap = instance["android.app.LoadedApk", "mReceivers"]!!.valueAsInstance!!
        val receiversArray = receiversMap["android.util.ArrayMap", "mArray"]!!.valueAsObjectArray!!
        val receiverContextList = receiversArray.readElements().toList()

        val allReceivers = (receiverContextList.indices step 2).mapNotNull { index ->
          val context = receiverContextList[index]
          if (context.isNonNullReference) {
            val contextReceiversMap = receiverContextList[index + 1].asObject!!.asInstance!!
            val contextReceivers = contextReceiversMap["android.util.ArrayMap", "mArray"]!!
              .valueAsObjectArray!!
              .readElements()
              .toList()

            val receivers =
              (contextReceivers.indices step 2).mapNotNull { contextReceivers[it].asObject?.asInstance }
            val contextInstance = context.asObject!!.asInstance!!
            val contextString =
              "${contextInstance.instanceClassSimpleName}@${contextInstance.objectId}"
            contextString to receivers.map { "${it.instanceClassSimpleName}@${it.objectId}" }
          } else {
            null
          }
        }.toList()

        if (allReceivers.isNotEmpty()) {
          labels += "Receivers"
          allReceivers.forEach { (contextString, receiverStrings) ->
            labels += "..$contextString"
            receiverStrings.forEach { receiverString ->
              labels += "....$receiverString"
            }
          }
        }
      }
    }
  },

  MORTAR_PRESENTER {
    override fun inspect(
      reporter: ObjectReporter
    ) {
      reporter.whenInstanceOf("mortar.Presenter") { instance ->
        val view = instance.getOrThrow("mortar.Presenter", "view")
        labels += view describedWithValue if (view.value.isNullReference) "null" else "not null"
      }
    }
  },

  MORTAR_SCOPE {
    override val leakingObjectFilter = { heapObject: HeapObject ->
      heapObject is HeapInstance &&
        heapObject instanceOf "mortar.MortarScope" &&
        heapObject.getOrThrow("mortar.MortarScope", "dead").value.asBoolean!!
    }

    override fun inspect(reporter: ObjectReporter) {
      reporter.whenInstanceOf("mortar.MortarScope") { instance ->
        val dead = instance.getOrThrow("mortar.MortarScope", "dead").value.asBoolean!!
        val scopeName = instance.getOrThrow("mortar.MortarScope", "name").value.readAsJavaString()
        if (dead) {
          leakingReasons += "mortar.MortarScope.dead is true for scope $scopeName"
        } else {
          notLeakingReasons += "mortar.MortarScope.dead is false for scope $scopeName"
        }
      }
    }
  },

  COORDINATOR {
    override fun inspect(
      reporter: ObjectReporter
    ) {
      reporter.whenInstanceOf("com.squareup.coordinators.Coordinator") { instance ->
        val attached = instance.getOrThrow("com.squareup.coordinators.Coordinator", "attached")
        labels += attached describedWithValue "${attached.value.asBoolean}"
      }
    }
  },

  MAIN_THREAD {
    override fun inspect(
      reporter: ObjectReporter
    ) {
      reporter.whenInstanceOf(Thread::class) { instance ->
        val threadName = instance[Thread::class, "name"]!!.value.readAsJavaString()
        if (threadName == "main") {
          notLeakingReasons += "the main thread always runs"
        }
      }
    }
  },

  VIEW_ROOT_IMPL {
    override val leakingObjectFilter = { heapObject: HeapObject ->
      if (heapObject is HeapInstance &&
        heapObject instanceOf "android.view.ViewRootImpl"
      ) {
        if (heapObject["android.view.ViewRootImpl", "mView"]!!.value.isNullReference) {
          true
        } else {
          val mContextField = heapObject["android.view.ViewRootImpl", "mContext"]
          if (mContextField != null) {
            val mContext = mContextField.valueAsInstance!!
            val activityContext = mContext.unwrapActivityContext()
            (activityContext != null && activityContext["android.app.Activity", "mDestroyed"]?.value?.asBoolean == true)
          } else {
            false
          }
        }
      } else {
        false
      }
    }

    override fun inspect(reporter: ObjectReporter) {
      reporter.whenInstanceOf("android.view.ViewRootImpl") { instance ->
        val mViewField = instance["android.view.ViewRootImpl", "mView"]!!
        if (mViewField.value.isNullReference) {
          leakingReasons += mViewField describedWithValue "null"
        } else {
          // ViewRootImpl.mContext wasn't always here.
          val mContextField = instance["android.view.ViewRootImpl", "mContext"]
          if (mContextField != null) {
            val mContext = mContextField.valueAsInstance!!
            val activityContext = mContext.unwrapActivityContext()
            if (activityContext != null && activityContext["android.app.Activity", "mDestroyed"]?.value?.asBoolean == true) {
              leakingReasons += "ViewRootImpl.mContext references a destroyed activity, did you forget to cancel toasts or dismiss dialogs?"
            }
          }
          labels += mViewField describedWithValue "not null"
        }
        val mWindowAttributes =
          instance["android.view.ViewRootImpl", "mWindowAttributes"]!!.valueAsInstance!!
        val mTitleField = mWindowAttributes["android.view.WindowManager\$LayoutParams", "mTitle"]!!
        labels += if (mTitleField.value.isNonNullReference) {
          val mTitle =
            mTitleField.valueAsInstance!!.readAsJavaString()!!
          "mWindowAttributes.mTitle = \"$mTitle\""
        } else {
          "mWindowAttributes.mTitle is null"
        }

        val type =
          mWindowAttributes["android.view.WindowManager\$LayoutParams", "type"]!!.value.asInt!!
        // android.view.WindowManager.LayoutParams.TYPE_TOAST
        val details = if (type == 2005) {
          " (Toast)"
        } else ""
        labels += "mWindowAttributes.type = $type$details"
      }
    }
  },

  WINDOW {
    override val leakingObjectFilter = { heapObject: HeapObject ->
      heapObject is HeapInstance &&
        heapObject instanceOf "android.view.Window" &&
        heapObject["android.view.Window", "mDestroyed"]!!.value.asBoolean!!
    }

    override fun inspect(
      reporter: ObjectReporter
    ) {
      reporter.whenInstanceOf("android.view.Window") { instance ->
        val mDestroyed = instance["android.view.Window", "mDestroyed"]!!

        if (mDestroyed.value.asBoolean!!) {
          leakingReasons += mDestroyed describedWithValue "true"
        } else {
          // A dialog window could be leaking, destroy is only set to false for activity windows.
          labels += mDestroyed describedWithValue "false"
        }
      }
    }
  },

  MESSAGE {
    override fun inspect(reporter: ObjectReporter) {
      reporter.whenInstanceOf("android.os.Message") { instance ->
        labels += "Message.what = ${instance["android.os.Message", "what"]!!.value.asInt}"

        val heapDumpUptimeMillis = KeyedWeakReferenceFinder.heapDumpUptimeMillis(instance.graph)
        val whenUptimeMillis = instance["android.os.Message", "when"]!!.value.asLong!!

        labels += if (heapDumpUptimeMillis != null) {
          val diffMs = whenUptimeMillis - heapDumpUptimeMillis
          if (diffMs > 0) {
            "Message.when = $whenUptimeMillis ($diffMs ms after heap dump)"
          } else {
            "Message.when = $whenUptimeMillis (${diffMs.absoluteValue} ms before heap dump)"
          }
        } else {
          "Message.when = $whenUptimeMillis"
        }

        labels += "Message.obj = ${instance["android.os.Message", "obj"]!!.value.asObject}"
        labels += "Message.callback = ${instance["android.os.Message", "callback"]!!.value.asObject}"
        labels += "Message.target = ${instance["android.os.Message", "target"]!!.value.asObject}"
      }
    }
  },

  TOAST {
    override val leakingObjectFilter = { heapObject: HeapObject ->
      if (heapObject is HeapInstance && heapObject instanceOf "android.widget.Toast") {
        val tnInstance =
          heapObject["android.widget.Toast", "mTN"]!!.value.asObject!!.asInstance!!
        (tnInstance["android.widget.Toast\$TN", "mWM"]!!.value.isNonNullReference &&
          tnInstance["android.widget.Toast\$TN", "mView"]!!.value.isNullReference)
      } else false
    }

    override fun inspect(
      reporter: ObjectReporter
    ) {
      reporter.whenInstanceOf("android.widget.Toast") { instance ->
        val tnInstance =
          instance["android.widget.Toast", "mTN"]!!.value.asObject!!.asInstance!!
        // mWM is set in android.widget.Toast.TN#handleShow and never unset, so this toast was never
        // shown, we don't know if it's leaking.
        if (tnInstance["android.widget.Toast\$TN", "mWM"]!!.value.isNonNullReference) {
          // mView is reset to null in android.widget.Toast.TN#handleHide
          if (tnInstance["android.widget.Toast\$TN", "mView"]!!.value.isNullReference) {
            leakingReasons += "This toast is done showing (Toast.mTN.mWM != null && Toast.mTN.mView == null)"
          } else {
            notLeakingReasons += "This toast is showing (Toast.mTN.mWM != null && Toast.mTN.mView != null)"
          }
        }
      }
    }
  },

  RECOMPOSER {
    override fun inspect(reporter: ObjectReporter) {
      reporter.whenInstanceOf("androidx.compose.runtime.Recomposer") { instance ->
        val stateFlow =
          instance["androidx.compose.runtime.Recomposer", "_state"]!!.valueAsInstance!!
        val state = stateFlow["kotlinx.coroutines.flow.StateFlowImpl", "_state"]?.valueAsInstance
        if (state != null) {
          val stateName = state["java.lang.Enum", "name"]!!.valueAsInstance!!.readAsJavaString()!!
          val label = "Recomposer is in state $stateName"
          when (stateName) {
            "ShutDown", "ShuttingDown" -> leakingReasons += label
            "Inactive", "InactivePendingWork" -> labels += label
            "PendingWork", "Idle" -> notLeakingReasons += label
          }
        }
      }
    }
  },

  COMPOSITION_IMPL {
    override fun inspect(reporter: ObjectReporter) {
      reporter.whenInstanceOf("androidx.compose.runtime.CompositionImpl") { instance ->
        if (instance["androidx.compose.runtime.CompositionImpl", "disposed"]!!.value.asBoolean!!) {
          leakingReasons += "Composition disposed"
        } else {
          notLeakingReasons += "Composition not disposed"
        }
      }
    }
  },

  ANIMATOR {
    override fun inspect(reporter: ObjectReporter) {
      reporter.whenInstanceOf("android.animation.Animator") { instance ->
        val mListeners = instance["android.animation.Animator", "mListeners"]!!.valueAsInstance
        if (mListeners != null) {
          val listenerValues = InternalSharkCollectionsHelper.arrayListValues(mListeners).toList()
          if (listenerValues.isNotEmpty()) {
            listenerValues.forEach { value ->
              labels += "mListeners$value"
            }
          } else {
            labels += "mListeners is empty"
          }
        } else {
          labels += "mListeners = null"
        }
      }
    }
  },

  OBJECT_ANIMATOR {
    override fun inspect(reporter: ObjectReporter) {
      reporter.whenInstanceOf("android.animation.ObjectAnimator") { instance ->
        labels += "mPropertyName = " + (instance["android.animation.ObjectAnimator", "mPropertyName"]!!.valueAsInstance?.readAsJavaString()
          ?: "null")
        val mProperty = instance["android.animation.ObjectAnimator", "mProperty"]!!.valueAsInstance
        if (mProperty == null) {
          labels += "mProperty = null"
        } else {
          labels += "mProperty.mName = " + (mProperty["android.util.Property", "mName"]!!.valueAsInstance?.readAsJavaString()
            ?: "null")
          labels += "mProperty.mType = " + (mProperty["android.util.Property", "mType"]!!.valueAsClass?.name
            ?: "null")
        }
        labels += "mInitialized = " + instance["android.animation.ValueAnimator", "mInitialized"]!!.value.asBoolean!!
        labels += "mStarted = " + instance["android.animation.ValueAnimator", "mStarted"]!!.value.asBoolean!!
        labels += "mRunning = " + instance["android.animation.ValueAnimator", "mRunning"]!!.value.asBoolean!!
        labels += "mAnimationEndRequested = " + instance["android.animation.ValueAnimator", "mAnimationEndRequested"]!!.value.asBoolean!!
        labels += "mDuration = " + instance["android.animation.ValueAnimator", "mDuration"]!!.value.asLong!!
        labels += "mStartDelay = " + instance["android.animation.ValueAnimator", "mStartDelay"]!!.value.asLong!!
        val repeatCount = instance["android.animation.ValueAnimator", "mRepeatCount"]!!.value.asInt!!
        labels += "mRepeatCount = " + if (repeatCount == -1) "INFINITE (-1)" else repeatCount

        val repeatModeConstant = when (val repeatMode =
          instance["android.animation.ValueAnimator", "mRepeatMode"]!!.value.asInt!!) {
          1 -> "RESTART (1)"
          2 -> "REVERSE (2)"
          else -> "Unknown ($repeatMode)"
        }
        labels += "mRepeatMode = $repeatModeConstant"
      }
    }
  },

  LIFECYCLE_REGISTRY {
    override fun inspect(reporter: ObjectReporter) {
      reporter.whenInstanceOf("androidx.lifecycle.LifecycleRegistry") { instance ->
        val state = instance.lifecycleRegistryState
        // If state is DESTROYED, this doesn't mean the LifecycleRegistry itself is leaking.
        // Fragment.mViewLifecycleRegistry becomes DESTROYED when the fragment view is destroyed,
        // but the registry itself is still held in memory by the fragment.
        if (state != "DESTROYED") {
          notLeakingReasons += "state is $state"
        } else {
          labels += "state = $state"
        }
      }
    }
  },

  STUB {
    override fun inspect(reporter: ObjectReporter) {
      reporter.whenInstanceOf("android.os.Binder") { instance ->
        labels + "${instance.instanceClassSimpleName} is a binder stub. Binder stubs will often be" +
          " retained long after the associated activity or service is destroyed, as by design stubs" +
          " are retained until the other side gets GCed. If ${instance.instanceClassSimpleName} is" +
          " not a *static* inner class then that's most likely the root cause of this leak. Make" +
          " it static. If ${instance.instanceClassSimpleName} is an Android Framework class, file" +
          " a ticket here: https://issuetracker.google.com/issues/new?component=192705"
      }
    }
  },
  ;

  internal open val leakingObjectFilter: ((heapObject: HeapObject) -> Boolean)? = null

  companion object {
    /** @see AndroidObjectInspectors */
    val appDefaults: List<ObjectInspector>
      get() = ObjectInspectors.jdkDefaults + values()

    /**
     * Returns a list of [LeakingObjectFilter] suitable for apps.
     */
    val appLeakingObjectFilters: List<LeakingObjectFilter> =
      ObjectInspectors.jdkLeakingObjectFilters +
        createLeakingObjectFilters(EnumSet.allOf(AndroidObjectInspectors::class.java))

    /**
     * Creates a list of [LeakingObjectFilter] based on the passed in [AndroidObjectInspectors].
     */
    fun createLeakingObjectFilters(inspectors: Set<AndroidObjectInspectors>): List<LeakingObjectFilter> =
      inspectors.mapNotNull { it.leakingObjectFilter }
        .map { filter ->
          LeakingObjectFilter { heapObject -> filter(heapObject) }
        }
  }

  // Using a string builder to prevent Jetifier from changing this string to Android X Fragment
  @Suppress("VariableNaming", "PropertyName")
  internal val ANDROID_SUPPORT_FRAGMENT_CLASS_NAME =
    StringBuilder("android.").append("support.v4.app.Fragment")
      .toString()
}

private fun HeapInstance.outerContextIsLeaking() =
  this["android.app.ContextImpl", "mOuterContext"]!!
    .valueAsInstance!!
    .run {
      this instanceOf "android.app.Activity" &&
        this["android.app.Activity", "mDestroyed"]?.value?.asBoolean == true
    }

private fun ObjectReporter.inspectContextImplOuterContext(
  outerContext: HeapInstance,
  contextImpl: HeapInstance,
  prefix: String = "ContextImpl"
) {
  if (outerContext instanceOf "android.app.Activity") {
    val mDestroyed = outerContext["android.app.Activity", "mDestroyed"]?.value?.asBoolean
    if (mDestroyed != null) {
      if (mDestroyed) {
        leakingReasons += "$prefix.mOuterContext is an instance of" +
          " ${outerContext.instanceClassName} with Activity.mDestroyed true"
      } else {
        notLeakingReasons += "$prefix.mOuterContext is an instance of " +
          "${outerContext.instanceClassName} with Activity.mDestroyed false"
      }
    } else {
      labels += "$prefix.mOuterContext is an instance of ${outerContext.instanceClassName}"
    }
  } else if (outerContext instanceOf "android.app.Application") {
    notLeakingReasons += "$prefix.mOuterContext is an instance of" +
      " ${outerContext.instanceClassName} which extends android.app.Application"
  } else if (outerContext.objectId == contextImpl.objectId) {
    labels += "$prefix.mOuterContext == ContextImpl.this: not tied to any particular lifecycle"
  } else {
    labels += "$prefix.mOuterContext is an instance of ${outerContext.instanceClassName}"
  }
}

private infix fun HeapField.describedWithValue(valueDescription: String): String {
  return "${declaringClass.simpleName}#$name is $valueDescription"
}

private fun ObjectReporter.applyFromField(
  inspector: ObjectInspector,
  field: HeapField?
) {
  if (field == null) {
    return
  }
  if (field.value.isNullReference) {
    return
  }
  val heapObject = field.value.asObject!!
  val delegateReporter = ObjectReporter(heapObject)
  inspector.inspect(delegateReporter)
  val prefix = "${field.declaringClass.simpleName}#${field.name}:"

  labels += delegateReporter.labels.map { "$prefix $it" }
  leakingReasons += delegateReporter.leakingReasons.map { "$prefix $it" }
  notLeakingReasons += delegateReporter.notLeakingReasons.map { "$prefix $it" }
}

private val HeapInstance.lifecycleRegistryState: String
  get() {
    // LifecycleRegistry was converted to Kotlin
    // https://cs.android.com/androidx/platform/frameworks/support/+/36833f9ab0c50bf449fc795e297a0e124df3356e
    val stateField = this["androidx.lifecycle.LifecycleRegistry", "state"]
      ?: this["androidx.lifecycle.LifecycleRegistry", "mState"]!!
    val state = stateField.valueAsInstance!!
    return state["java.lang.Enum", "name"]!!.value.readAsJavaString()!!
}

/**
 * Recursively unwraps `this` [HeapInstance] as a ContextWrapper until an Activity is found in which case it is
 * returned. Returns null if no activity was found.
 */
internal fun HeapInstance.unwrapActivityContext(): HeapInstance? {
  return unwrapComponentContext().let { context ->
    if (context != null && context instanceOf "android.app.Activity") {
      context
    } else {
      null
    }
  }
}

/**
 * Recursively unwraps `this` [HeapInstance] as a ContextWrapper until an known Android component
 * context is found in which case it is returned. Returns null if no activity was found.
 */
@Suppress("NestedBlockDepth", "ReturnCount")
internal fun HeapInstance.unwrapComponentContext(): HeapInstance? {
  val matchingClassName = instanceClass.classHierarchy.map { it.name }
    .firstOrNull {
      when (it) {
        "android.content.ContextWrapper",
        "android.app.Activity",
        "android.app.Application",
        "android.app.Service"
        -> true
        else -> false
      }
    }
    ?: return null

  if (matchingClassName != "android.content.ContextWrapper") {
    return this
  }

  var context = this
  val visitedInstances = mutableListOf<Long>()
  var keepUnwrapping = true
  while (keepUnwrapping) {
    visitedInstances += context.objectId
    keepUnwrapping = false
    val mBase = context["android.content.ContextWrapper", "mBase"]!!.value

    if (mBase.isNonNullReference) {
      val wrapperContext = context
      context = mBase.asObject!!.asInstance!!

      val contextMatchingClassName = context.instanceClass.classHierarchy.map { it.name }
        .firstOrNull {
          when (it) {
            "android.content.ContextWrapper",
            "android.app.Activity",
            "android.app.Application",
            "android.app.Service"
            -> true
            else -> false
          }
        }

      var isContextWrapper = contextMatchingClassName == "android.content.ContextWrapper"

      if (contextMatchingClassName == "android.app.Activity") {
        return context
      } else {
        if (wrapperContext instanceOf "com.android.internal.policy.DecorContext") {
          // mBase isn't an activity, let's unwrap DecorContext.mPhoneWindow.mContext instead
          val mPhoneWindowField =
            wrapperContext["com.android.internal.policy.DecorContext", "mPhoneWindow"]
          if (mPhoneWindowField != null) {
            val phoneWindow = mPhoneWindowField.valueAsInstance!!
            context = phoneWindow["android.view.Window", "mContext"]!!.valueAsInstance!!
            if (context instanceOf "android.app.Activity") {
              return context
            }
            isContextWrapper = context instanceOf "android.content.ContextWrapper"
          }
        }
        if (contextMatchingClassName == "android.app.Service" ||
          contextMatchingClassName == "android.app.Application"
        ) {
          return context
        }
        if (isContextWrapper &&
          // Avoids infinite loops
          context.objectId !in visitedInstances
        ) {
          keepUnwrapping = true
        }
      }
    }
  }
  return null
}

/**
 * Same as [HeapInstance.readField] but throws if the field doesnt exist
 */
internal fun HeapInstance.getOrThrow(
  declaringClassName: String,
  fieldName: String
): HeapField {
  return this[declaringClassName, fieldName] ?: throw IllegalStateException(
    """
$instanceClassName is expected to have a $declaringClassName.$fieldName field which cannot be found.
This might be due to the app code being obfuscated. If that's the case, then the heap analysis
is unable to proceed without a mapping file to deobfuscate class names.
You can run LeakCanary on obfuscated builds by following the instructions at
https://square.github.io/leakcanary/recipes/#using-leakcanary-with-obfuscated-apps
      """
  )
}