/*
 * Copyright (c) 2020 New Vector Ltd
 *
 * 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 im.vector.riotx.features.settings.devtools

import com.airbnb.mvrx.Async
import com.airbnb.mvrx.FragmentViewModelContext
import com.airbnb.mvrx.Loading
import com.airbnb.mvrx.MvRxState
import com.airbnb.mvrx.MvRxViewModelFactory
import com.airbnb.mvrx.Success
import com.airbnb.mvrx.Uninitialized
import com.airbnb.mvrx.ViewModelContext
import com.squareup.inject.assisted.Assisted
import com.squareup.inject.assisted.AssistedInject
import im.vector.matrix.android.api.session.Session
import im.vector.matrix.android.api.session.events.model.Event
import im.vector.riotx.core.platform.EmptyAction
import im.vector.riotx.core.platform.EmptyViewEvents
import im.vector.riotx.core.platform.VectorViewModel
import kotlinx.coroutines.GlobalScope
import kotlinx.coroutines.launch

data class GossipingEventsPaperTrailState(
        val events: Async<List<Event>> = Uninitialized
) : MvRxState

class GossipingEventsPaperTrailViewModel @AssistedInject constructor(@Assisted initialState: GossipingEventsPaperTrailState,
                                                                     private val session: Session)
    : VectorViewModel<GossipingEventsPaperTrailState, EmptyAction, EmptyViewEvents>(initialState) {

    init {
        refresh()
    }

    fun refresh() {
        setState {
            copy(events = Loading())
        }
        GlobalScope.launch {
            session.cryptoService().getGossipingEventsTrail().let {
                val sorted = it.sortedByDescending { it.ageLocalTs }
                setState {
                    copy(events = Success(sorted))
                }
            }
        }
    }

    override fun handle(action: EmptyAction) {}

    @AssistedInject.Factory
    interface Factory {
        fun create(initialState: GossipingEventsPaperTrailState): GossipingEventsPaperTrailViewModel
    }

    companion object : MvRxViewModelFactory<GossipingEventsPaperTrailViewModel, GossipingEventsPaperTrailState> {

        @JvmStatic
        override fun create(viewModelContext: ViewModelContext, state: GossipingEventsPaperTrailState): GossipingEventsPaperTrailViewModel? {
            val fragment: GossipingEventsPaperTrailFragment = (viewModelContext as FragmentViewModelContext).fragment()

            return fragment.viewModelFactory.create(state)
        }
    }
}
