Add IconViewModel load icons on the uiBackground thread

/*

 * 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.systemui.screencapture.common.ui.compose

import android.graphics.drawable.Drawable

import androidx.annotation.DrawableRes

import androidx.compose.runtime.Composable

import androidx.compose.runtime.getValue

import androidx.compose.runtime.produceState

import androidx.compose.ui.platform.LocalContext

import com.android.systemui.screencapture.common.ui.viewmodel.DrawableLoaderViewModel

/** @see DrawableLoaderViewModel */

@Composable

fun loadDrawable(viewModel: DrawableLoaderViewModel, @DrawableRes resId: Int): Drawable? {

    val context = LocalContext.current

    val drawable by

        produceState<Drawable?>(initialValue = null, keys = arrayOf(viewModel, context, resId)) {

            value = viewModel.loadDrawable(context = context, resId = resId)

        }

    return drawable

}

/*

 * 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.systemui.screencapture.common.ui.compose

import androidx.annotation.DrawableRes

import androidx.compose.runtime.Composable

import com.android.systemui.common.shared.model.ContentDescription

import com.android.systemui.common.shared.model.Icon

import com.android.systemui.screencapture.common.ui.viewmodel.DrawableLoaderViewModel

/** @see DrawableLoaderViewModel */

@Composable

fun loadIcon(

    viewModel: DrawableLoaderViewModel,

    @DrawableRes resId: Int,

    contentDescription: ContentDescription?,

): Icon.Loaded? {

    return loadDrawable(viewModel, resId)?.let { drawable ->

        Icon.Loaded(drawable = drawable, res = resId, contentDescription = contentDescription)

    }

}

/*

 * 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.systemui.screencapture.common.ui.viewmodel

import android.annotation.SuppressLint

import android.content.Context

import android.graphics.drawable.Drawable

import androidx.annotation.DrawableRes

import com.android.systemui.dagger.qualifiers.UiBackground

import javax.inject.Inject

import kotlin.coroutines.CoroutineContext

import kotlinx.coroutines.withContext

/**

 * Interface to mark your ViewModels as ones capable of loading drawables. This enables it to load

 * them on [UiBackground] executor by using [DrawableLoaderViewModelImpl].

 *

 * Example:

 * ```

 * class FooViewModel(vm: DrawableLoaderViewModelImpl): DrawableLoaderViewModel by vm

 * ```

 *

 * And then in compose:

 * ```

 * @Composable

 * fun Foo(viewModel: FooViewModel) {

 *   loadIcon(viewModel, R.drawable.icon)?.let { Icon(it) }

 * }

 * ```

 */

interface DrawableLoaderViewModel {

    suspend fun loadDrawable(context: Context, @DrawableRes resId: Int): Drawable

}

class DrawableLoaderViewModelImpl

@Inject

constructor(@UiBackground private val uiBackgroundCoroutineContext: CoroutineContext) :

    DrawableLoaderViewModel {

    @SuppressLint("UseCompatLoadingForDrawables")

    override suspend fun loadDrawable(context: Context, @DrawableRes resId: Int): Drawable =

        withContext(uiBackgroundCoroutineContext) { context.getDrawable(resId)!! }

}

/*

 * 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.systemui.screencapture.common.ui.viewmodel

import com.android.systemui.kosmos.Kosmos

import com.android.systemui.kosmos.backgroundCoroutineContext

val Kosmos.drawableLoaderViewModelImpl: DrawableLoaderViewModelImpl by

    Kosmos.Fixture {

        DrawableLoaderViewModelImpl(uiBackgroundCoroutineContext = backgroundCoroutineContext)

    }

var Kosmos.drawableLoaderViewModel: DrawableLoaderViewModel by

    Kosmos.Fixture { drawableLoaderViewModelImpl }