/*
 * Copyright (C) 2022 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.media

import android.animation.ValueAnimator
import android.graphics.Color
import android.testing.AndroidTestingRunner
import android.testing.TestableLooper
import androidx.test.filters.SmallTest
import com.android.systemui.SysuiTestCase
import com.android.systemui.monet.ColorScheme
import junit.framework.Assert.assertEquals
import org.junit.After
import org.junit.Before
import org.junit.Rule
import org.junit.Test
import org.junit.runner.RunWith
import org.mockito.Mock
import org.mockito.Mockito.never
import org.mockito.Mockito.times
import org.mockito.Mockito.verify
import org.mockito.Mockito.`when` as whenever
import org.mockito.junit.MockitoJUnit

private const val DEFAULT_COLOR = Color.RED
private const val TARGET_COLOR = Color.BLUE

@SmallTest
@RunWith(AndroidTestingRunner::class)
@TestableLooper.RunWithLooper(setAsMainLooper = true)
class ColorSchemeTransitionTest : SysuiTestCase() {

    private interface ExtractCB : (ColorScheme) -> Int
    private interface ApplyCB : (Int) -> Unit
    private lateinit var colorTransition: AnimatingColorTransition
    private lateinit var colorSchemeTransition: ColorSchemeTransition

    @Mock private lateinit var mockAnimatingTransition: AnimatingColorTransition
    @Mock private lateinit var valueAnimator: ValueAnimator
    @Mock private lateinit var colorScheme: ColorScheme
    @Mock private lateinit var extractColor: ExtractCB
    @Mock private lateinit var applyColor: ApplyCB

    private lateinit var animatingColorTransitionFactory: AnimatingColorTransitionFactory
    @Mock private lateinit var mediaViewHolder: MediaViewHolder
    @Mock private lateinit var gutsViewHolder: GutsViewHolder

    @JvmField @Rule val mockitoRule = MockitoJUnit.rule()

    @Before
    fun setUp() {
        whenever(mediaViewHolder.gutsViewHolder).thenReturn(gutsViewHolder)
        animatingColorTransitionFactory = { _, _, _ -> mockAnimatingTransition }
        whenever(extractColor.invoke(colorScheme)).thenReturn(TARGET_COLOR)

        colorSchemeTransition = ColorSchemeTransition(
            context, mediaViewHolder, animatingColorTransitionFactory
        )

        colorTransition = object : AnimatingColorTransition(
            DEFAULT_COLOR, extractColor, applyColor
        ) {
            override fun buildAnimator(): ValueAnimator {
                return valueAnimator
            }
        }
    }

    @After
    fun tearDown() {}

    @Test
    fun testColorTransition_nullColorScheme_keepsDefault() {
        colorTransition.updateColorScheme(null)
        verify(applyColor, times(1)).invoke(DEFAULT_COLOR)
        verify(valueAnimator, never()).start()
        assertEquals(DEFAULT_COLOR, colorTransition.sourceColor)
        assertEquals(DEFAULT_COLOR, colorTransition.targetColor)
    }

    @Test
    fun testColorTransition_newColor_startsAnimation() {
        colorTransition.updateColorScheme(colorScheme)
        verify(applyColor, times(1)).invoke(DEFAULT_COLOR)
        verify(valueAnimator, times(1)).start()
        assertEquals(DEFAULT_COLOR, colorTransition.sourceColor)
        assertEquals(TARGET_COLOR, colorTransition.targetColor)
    }

    @Test
    fun testColorTransition_sameColor_noAnimation() {
        whenever(extractColor.invoke(colorScheme)).thenReturn(DEFAULT_COLOR)
        colorTransition.updateColorScheme(colorScheme)
        verify(valueAnimator, never()).start()
        assertEquals(DEFAULT_COLOR, colorTransition.sourceColor)
        assertEquals(DEFAULT_COLOR, colorTransition.targetColor)
    }

    @Test
    fun testColorTransition_colorAnimation_startValues() {
        val expectedColor = DEFAULT_COLOR
        whenever(valueAnimator.animatedFraction).thenReturn(0f)
        colorTransition.updateColorScheme(colorScheme)
        colorTransition.onAnimationUpdate(valueAnimator)

        assertEquals(expectedColor, colorTransition.currentColor)
        assertEquals(expectedColor, colorTransition.sourceColor)
        verify(applyColor, times(2)).invoke(expectedColor) // applied once in constructor
    }

    @Test
    fun testColorTransition_colorAnimation_endValues() {
        val expectedColor = TARGET_COLOR
        whenever(valueAnimator.animatedFraction).thenReturn(1f)
        colorTransition.updateColorScheme(colorScheme)
        colorTransition.onAnimationUpdate(valueAnimator)

        assertEquals(expectedColor, colorTransition.currentColor)
        assertEquals(expectedColor, colorTransition.targetColor)
        verify(applyColor).invoke(expectedColor)
    }

    @Test
    fun testColorTransition_colorAnimation_interpolatedMidpoint() {
        val expectedColor = Color.rgb(186, 0, 186)
        whenever(valueAnimator.animatedFraction).thenReturn(0.5f)
        colorTransition.updateColorScheme(colorScheme)
        colorTransition.onAnimationUpdate(valueAnimator)

        assertEquals(expectedColor, colorTransition.currentColor)
        verify(applyColor).invoke(expectedColor)
    }

    @Test
    fun testColorSchemeTransition_update() {
        colorSchemeTransition.updateColorScheme(colorScheme)
        verify(mockAnimatingTransition, times(8)).updateColorScheme(colorScheme)
        verify(gutsViewHolder).colorScheme = colorScheme
    }
}