/*
 * 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.launcher3.model.tasks

import com.android.launcher3.model.data.ItemInfo
import com.android.launcher3.model.data.WorkspaceChangeEvent
import com.android.launcher3.model.data.WorkspaceChangeEvent.RemoveEvent
import com.android.launcher3.model.data.WorkspaceChangeEvent.UpdateEvent
import com.android.launcher3.model.data.WorkspaceData
import com.android.launcher3.model.tasks.ModelRepoTestEx.TrackedUpdates
import com.android.launcher3.util.Executors
import com.android.launcher3.util.ListenableDiffAwareRef
import com.android.launcher3.util.ListenableStream
import com.android.launcher3.util.TestUtil
import com.google.common.truth.Truth.assertThat

typealias TrackedWorkspaceUpdates = TrackedUpdates<WorkspaceData, WorkspaceChangeEvent?>

object ModelRepoTestEx {

    fun <T> ListenableStream<T>.trackUpdate() =
        mutableListOf<T>().also { updates ->
            TestUtil.runOnExecutorSync(Executors.MODEL_EXECUTOR) {}
            forEach(Executors.MODEL_EXECUTOR) { updates.add(it) }
        }

    fun <T, R> ListenableDiffAwareRef<T, R>.trackUpdateAndChanges() =
        TrackedUpdates(updates = trackUpdate(), changes = changes.trackUpdate())

    /** Verifies that the update list contains an update operation, and returns the updated items */
    fun TrackedWorkspaceUpdates.verifyAndGetItemsUpdated(
        updateIndex: Int = 1,
        totalUpdates: Int = 2,
    ): List<ItemInfo> {
        assertThat(updates).hasSize(totalUpdates)
        assertThat(changes).hasSize(totalUpdates - 1)
        val updates = changes[updateIndex - 1] as UpdateEvent
        return updates.items
    }

    /** Verifies that the update list contains a delete operation */
    fun TrackedWorkspaceUpdates.verifyDelete(deleteIndex: Int = 1, totalUpdates: Int = 2) {
        assertThat(updates).hasSize(totalUpdates)
        assertThat(changes).hasSize(totalUpdates - 1)
        assertThat(changes[deleteIndex - 1]).isInstanceOf(RemoveEvent::class.java)
    }

    data class TrackedUpdates<T, R>(val updates: List<T>, val changes: List<R>)
}