/*
 * Copyright (C) 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 com.android.systemui.animation

import android.os.HandlerThread
import android.platform.test.annotations.DisableFlags
import android.platform.test.annotations.EnableFlags
import android.testing.TestableLooper
import android.view.View
import android.widget.FrameLayout
import androidx.test.ext.junit.runners.AndroidJUnit4
import androidx.test.filters.SmallTest
import com.android.internal.jank.InteractionJankMonitor
import com.android.systemui.Flags
import com.android.systemui.SysuiTestCase
import com.android.systemui.animation.view.LaunchableFrameLayout
import com.google.common.truth.Truth.assertThat
import org.junit.Assert.assertThrows
import org.junit.Before
import org.junit.Test
import org.junit.runner.RunWith

@SmallTest
@RunWith(AndroidJUnit4::class)
@TestableLooper.RunWithLooper
class GhostedViewTransitionAnimatorControllerTest : SysuiTestCase() {
    companion object {
        private const val LAUNCH_CUJ = 0
        private const val RETURN_CUJ = 1
    }

    private val interactionJankMonitor = FakeInteractionJankMonitor()
    private lateinit var transitionRegistry: FakeViewTransitionRegistry
    private lateinit var transitioningView: View

    @Before
    fun setup() {
        transitioningView = LaunchableFrameLayout(mContext)
        transitionRegistry = FakeViewTransitionRegistry()
    }

    @Test
    fun animatingOrphanViewDoesNotCrash() {
        val state = TransitionAnimator.State(top = 0, bottom = 0, left = 0, right = 0)

        val controller = GhostedViewTransitionAnimatorController(LaunchableFrameLayout(mContext))
        controller.onIntentStarted(willAnimate = true)
        controller.onTransitionAnimationStart(isExpandingFullyAbove = true)
        controller.onTransitionAnimationProgress(state, progress = 0f, linearProgress = 0f)
        controller.onTransitionAnimationEnd(isExpandingFullyAbove = true)
    }

    @Test
    fun creatingControllerFromNormalViewThrows() {
        assertThrows(IllegalArgumentException::class.java) {
            GhostedViewTransitionAnimatorController(FrameLayout(mContext))
        }
    }

    @Test
    fun cujsAreLoggedCorrectly() {
        val parent = FrameLayout(mContext)

        val launchView = LaunchableFrameLayout(mContext)
        parent.addView((launchView))
        val launchController =
            GhostedViewTransitionAnimatorController(
                launchView,
                launchCujType = LAUNCH_CUJ,
                returnCujType = RETURN_CUJ,
                interactionJankMonitor = interactionJankMonitor,
            )
        launchController.onTransitionAnimationStart(isExpandingFullyAbove = true)
        assertThat(interactionJankMonitor.ongoing).containsExactly(LAUNCH_CUJ)
        launchController.onTransitionAnimationEnd(isExpandingFullyAbove = true)
        assertThat(interactionJankMonitor.ongoing).isEmpty()
        assertThat(interactionJankMonitor.finished).containsExactly(LAUNCH_CUJ)

        val returnView = LaunchableFrameLayout(mContext)
        parent.addView((returnView))
        val returnController =
            object :
                GhostedViewTransitionAnimatorController(
                    returnView,
                    launchCujType = LAUNCH_CUJ,
                    returnCujType = RETURN_CUJ,
                    interactionJankMonitor = interactionJankMonitor,
                ) {
                override val isLaunching = false
            }
        returnController.onTransitionAnimationStart(isExpandingFullyAbove = true)
        assertThat(interactionJankMonitor.ongoing).containsExactly(RETURN_CUJ)
        returnController.onTransitionAnimationEnd(isExpandingFullyAbove = true)
        assertThat(interactionJankMonitor.ongoing).isEmpty()
        assertThat(interactionJankMonitor.finished).containsExactly(LAUNCH_CUJ, RETURN_CUJ)
    }

    @EnableFlags(Flags.FLAG_DECOUPLE_VIEW_CONTROLLER_IN_ANIMLIB)
    @Test
    fun testViewsAreRegisteredInTransitionRegistry() {
        GhostedViewTransitionAnimatorController(
            transitioningView = transitioningView,
            transitionRegistry = transitionRegistry,
        )
        assertThat(transitionRegistry.registry).isNotEmpty()
    }

    @DisableFlags(Flags.FLAG_DECOUPLE_VIEW_CONTROLLER_IN_ANIMLIB)
    @Test
    fun testNotUseRegistryIfDecouplingFlagDisabled() {
        GhostedViewTransitionAnimatorController(
            transitioningView = transitioningView,
            transitionRegistry = transitionRegistry,
        )
        assertThat(transitionRegistry.registry).isEmpty()
    }

    /**
     * A fake implementation of [InteractionJankMonitor] which stores ongoing and finished CUJs and
     * allows inspection.
     */
    private class FakeInteractionJankMonitor : InteractionJankMonitor(HandlerThread("testThread")) {
        val ongoing: MutableSet<Int> = mutableSetOf()
        val finished: MutableSet<Int> = mutableSetOf()

        override fun begin(v: View?, cujType: Int): Boolean {
            ongoing.add(cujType)
            return true
        }

        override fun end(cujType: Int): Boolean {
            ongoing.remove(cujType)
            finished.add(cujType)
            return true
        }
    }

    private class FakeViewTransitionRegistry : ViewTransitionRegistry {

        val registry = mutableMapOf<ViewTransitionToken, View>()
        val token = ViewTransitionToken()

        override fun register(view: View): ViewTransitionToken {
            registry[token] = view
            view.setTag(R.id.tag_view_transition_token, token)
            return token
        }

        override fun unregister(token: ViewTransitionToken) {
            registry.remove(token)?.setTag(R.id.tag_view_transition_token, null)
        }

        override fun getView(token: ViewTransitionToken): View? {
            return registry[token]
        }

        override fun getViewToken(view: View): ViewTransitionToken? {
            return view.getTag(R.id.tag_view_transition_token) as? ViewTransitionToken
        }

        override fun onRegistryUpdate() {
            // empty
        }
    }
}