/*
 * SPDX-FileCopyrightText: 2020, microG Project Team
 * SPDX-License-Identifier: Apache-2.0
 */

package org.microg.gms.nearby.core.ui

import android.annotation.TargetApi
import android.os.Bundle
import android.text.format.DateFormat
import androidx.lifecycle.lifecycleScope
import androidx.preference.PreferenceCategory
import androidx.preference.PreferenceFragmentCompat
import com.db.williamchart.data.Scale
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.withContext
import org.microg.gms.nearby.exposurenotification.ExposureDatabase
import java.util.*
import kotlin.math.roundToInt
import kotlin.math.roundToLong

@TargetApi(21)
class ExposureNotificationsRpisFragment : PreferenceFragmentCompat() {
    private lateinit var histogramCategory: PreferenceCategory
    private lateinit var histogram: BarChartPreference

    override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
        addPreferencesFromResource(R.xml.preferences_exposure_notifications_rpis)
    }

    override fun onBindPreferences() {
        histogramCategory = preferenceScreen.findPreference("prefcat_exposure_rpi_histogram") ?: histogramCategory
        histogram = preferenceScreen.findPreference("pref_exposure_rpi_histogram") ?: histogram
    }

    override fun onResume() {
        super.onResume()
        updateChart()
    }

    fun updateChart() {
        lifecycleScope.launchWhenResumed {
            val (totalRpiCount, rpiHistogram) = ExposureDatabase.with(requireContext()) { database ->
                val map = linkedMapOf<String, Float>()
                val lowestDate = (System.currentTimeMillis() / 24 / 60 / 60 / 1000 - 13).toDouble().roundToLong() * 24 * 60 * 60 * 1000
                for (i in 0..13) {
                    val date = Calendar.getInstance().apply { this.time = Date(lowestDate + i * 24 * 60 * 60 * 1000) }.get(Calendar.DAY_OF_MONTH)
                    val str = when (i) {
                        0, 13 -> DateFormat.format(DateFormat.getBestDateTimePattern(Locale.getDefault(), "MMMd"), lowestDate + i * 24 * 60 * 60 * 1000).toString()
                        else -> IntArray(date).joinToString("").replace("0", "\u200B")
                    }
                    map[str] = 0f
                }
                val refDateLow = Calendar.getInstance().apply { this.time = Date(lowestDate) }.get(Calendar.DAY_OF_MONTH)
                val refDateHigh = Calendar.getInstance().apply { this.time = Date(lowestDate + 13 * 24 * 60 * 60 * 1000) }.get(Calendar.DAY_OF_MONTH)
                for (entry in database.rpiHistogram) {
                    val time = Date(entry.key * 24 * 60 * 60 * 1000)
                    if (time.time < lowestDate) continue // Ignore old data
                    val date = Calendar.getInstance().apply { this.time = time }.get(Calendar.DAY_OF_MONTH)
                    val str = when (date) {
                        refDateLow, refDateHigh -> DateFormat.format(DateFormat.getBestDateTimePattern(Locale.getDefault(), "MMMd"), entry.key * 24 * 60 * 60 * 1000).toString()
                        else -> IntArray(date).joinToString("").replace("0", "\u200B")
                    }
                    map[str] = entry.value.toFloat()
                }
                val totalRpiCount = database.totalRpiCount
                totalRpiCount to map
            }
            histogramCategory.title = getString(R.string.prefcat_exposure_rpis_histogram_title, totalRpiCount)
            histogram.labelsFormatter = { it.roundToInt().toString() }
            histogram.scale = Scale(0f, rpiHistogram.values.max()?.coerceAtLeast(0.1f) ?: 0.1f)
            histogram.data = rpiHistogram
        }
    }
}