/*
 * Copyright (C) 2025 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.wallpaper.picker.common.preview.ui.binder

import android.view.View
import android.widget.TextView
import androidx.lifecycle.Lifecycle
import androidx.lifecycle.LifecycleOwner
import androidx.lifecycle.lifecycleScope
import androidx.lifecycle.repeatOnLifecycle
import com.android.wallpaper.R
import com.android.wallpaper.picker.customization.ui.util.ViewAlphaAnimator.animateToAlpha
import com.android.wallpaper.picker.customization.ui.viewmodel.CustomizationPickerViewModel2
import kotlinx.coroutines.launch

/**
 * Animates the preview and the preview label to a target alpha. The timing to call bind() is
 * critical. Avoid calling it during Activity or Fragment transition that also takes care of the
 * alpha fade of the screen.
 */
object PreviewAlphaAnimationBinder {

    fun bind(
        previewPager: View,
        viewModel: CustomizationPickerViewModel2,
        lifecycleOwner: LifecycleOwner,
    ) {
        val lockPreview: View = previewPager.requireViewById(R.id.lock_preview)
        val lockPreviewLabel: TextView = previewPager.requireViewById(R.id.lock_preview_label)
        val lockPreviewShade: View = lockPreview.requireViewById(R.id.preview_shade)
        val homePreview: View = previewPager.requireViewById(R.id.home_preview)
        val homePreviewLabel: TextView = previewPager.requireViewById(R.id.home_preview_label)
        val homePreviewShade: View = homePreview.requireViewById(R.id.preview_shade)

        lifecycleOwner.lifecycleScope.launch {
            lifecycleOwner.repeatOnLifecycle(Lifecycle.State.STARTED) {
                launch {
                    viewModel.lockPreviewAlpha.collect { (alpha, shouldAnimate) ->
                        val shadeAlpha = 1 - alpha
                        if (shouldAnimate) {
                            lockPreviewLabel.animateToAlpha(alpha)
                            lockPreviewShade.animateToAlpha(shadeAlpha)
                        } else {
                            lockPreviewLabel.alpha = alpha
                            lockPreviewShade.alpha = shadeAlpha
                        }
                    }
                }

                launch {
                    viewModel.homePreviewAlpha.collect { (alpha, shouldAnimate) ->
                        val shadeAlpha = 1 - alpha
                        if (shouldAnimate) {
                            homePreviewLabel.animateToAlpha(alpha)
                            homePreviewShade.animateToAlpha(shadeAlpha)
                        } else {
                            homePreviewLabel.alpha = alpha
                            homePreviewShade.alpha = shadeAlpha
                        }
                    }
                }

                launch {
                    viewModel.lockPreviewLabelTextAppearance.collect {
                        lockPreviewLabel.setTextAppearance(it)
                    }
                }

                launch {
                    viewModel.homePreviewLabelTextAppearance.collect {
                        homePreviewLabel.setTextAppearance(it)
                    }
                }
            }
        }
    }
}