/**
 * TrackerMap
 * Copyright (C) 2021-2022  Iván Ávalos <avalos@disroot.org>, Henoch Ojeda <imhenoch@protonmail.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
package mx.trackermap.TrackerMap.controllers

import kotlinx.coroutines.DelicateCoroutinesApi
import kotlinx.coroutines.GlobalScope
import kotlinx.coroutines.flow.MutableStateFlow
import kotlinx.coroutines.launch
import mx.trackermap.TrackerMap.Injectable
import mx.trackermap.TrackerMap.client.apis.GeofencesApi
import mx.trackermap.TrackerMap.client.apis.ReportsApi
import mx.trackermap.TrackerMap.client.models.EventInformation
import mx.trackermap.TrackerMap.client.models.Position
import mx.trackermap.TrackerMap.client.models.Stop
import mx.trackermap.TrackerMap.utils.ReportDates

@DelicateCoroutinesApi
class ReportController(
    private val reportsApi: ReportsApi,
    private val geofencesApi: GeofencesApi
): Injectable {

    sealed class Report {
        class PositionsReport(val positions: List<Position>) : Report()
        class EventsReport(val events: List<EventInformation>) : Report()
        class StopsReport(val stops: List<Stop>) : Report()
        class XlsxReport(val data: ByteArray) : Report()
        object LoadingReport: Report()
    }

    enum class ReportType {
        POSITIONS, EVENTS, STOPS
    }

    val reportFlow: MutableStateFlow<Report> = MutableStateFlow(Report.LoadingReport)

    fun fetchReport(
        deviceId: Int,
        reportType: ReportType?,
        reportPeriod: ReportDates.ReportPeriod?,
        xlsx: Boolean = false,
        eventTypes: List<EventInformation.Type> = listOf()
    ) {
        if (reportType == null || reportPeriod == null) {
            return
        }

        val (currentDate, previousDate) = ReportDates.getDates(reportPeriod)

        if (!xlsx) {
            reportFlow.value = Report.LoadingReport
        }
        GlobalScope.launch {
            when (reportType) {
                ReportType.POSITIONS -> fetchPositions(deviceId, previousDate, currentDate, xlsx)
                ReportType.EVENTS -> fetchEvents(deviceId, previousDate, currentDate, eventTypes, xlsx)
                ReportType.STOPS -> fetchStops(deviceId, previousDate, currentDate, xlsx)
            }
        }
    }

    private suspend fun fetchPositions(
        deviceId: Int,
        from: String,
        to: String,
        xlsx: Boolean
    ) {
        if (!xlsx) {
            val result = reportsApi.reportsRouteGet(from, to, deviceId)
            reportFlow.value = Report.PositionsReport(result.toList())
        } else {
            val result = reportsApi.reportsRouteGetXlsx(from, to, deviceId)
            reportFlow.value = Report.XlsxReport(result)
        }

    }

    private suspend fun fetchEvents(
        deviceId: Int,
        from: String,
        to: String,
        types: List<EventInformation.Type>,
        xlsx: Boolean
    ) {

        if (!xlsx) {
            val positionsResult = reportsApi.reportsRouteGet(from, to, deviceId)
            val eventsResult = reportsApi.reportsEventsGet(
                from, to, EventInformation.reportTypesToStrings(types), deviceId
            )
            val geofencesResult = geofencesApi.geofencesGet()

            val result = mutableListOf<EventInformation>()
            eventsResult.forEach { event ->
                result.add(EventInformation(
                    event = event,
                    position = positionsResult.find { it.id == event.positionId },
                    geofence = geofencesResult.find { it.id == event.geofenceId }
                ))
            }

            reportFlow.value = Report.EventsReport(result)
        } else {
            val result = reportsApi.reportsEventsGetXlsx(
                from, to, EventInformation.reportTypesToStrings(types), deviceId
            )

            reportFlow.value = Report.XlsxReport(result)
        }
    }

    private suspend fun fetchStops(
        deviceId: Int,
        from: String,
        to: String,
        xlsx: Boolean
    ) {
        if (!xlsx) {
            val result = reportsApi.reportsStopsGet(from, to, deviceId)
            reportFlow.value = Report.StopsReport(result.toList())
        } else {
            val result = reportsApi.reportsStopsGetXlsx(from, to, deviceId)
            reportFlow.value = Report.XlsxReport(result)
        }

    }
}