package com.vgmlr.kiln

import android.content.Context
import kotlinx.coroutines.flow.MutableStateFlow
import kotlinx.coroutines.flow.StateFlow
import androidx.core.content.edit

class KilnPrefs private constructor(context: Context) {
    private val store =
        context.applicationContext.getSharedPreferences(PREFS, Context.MODE_PRIVATE)

    private val _defaultAccountId = MutableStateFlow(store.getLong(KEY_DEFAULT, NO_ACCOUNT))
    val defaultAccountId: StateFlow<Long> = _defaultAccountId

    private val _loadDefaultOnStart = MutableStateFlow(store.getBoolean(KEY_LOAD_DEFAULT, false))
    val loadDefaultOnStart: StateFlow<Boolean> = _loadDefaultOnStart

    fun setDefaultAccount(id: Long) {
        store.edit { putLong(KEY_DEFAULT, id) }
        _defaultAccountId.value = id
    }

    fun setLoadDefaultOnStart(enabled: Boolean) {
        store.edit { putBoolean(KEY_LOAD_DEFAULT, enabled) }
        _loadDefaultOnStart.value = enabled
    }

    fun alertDay(key: String, accountId: Long): Long = store.getLong(key + accountId, NO_DAY)

    fun setAlertDay(key: String, accountId: Long, epochDay: Long) =
        store.edit { putLong(key + accountId, epochDay) }

    fun clearAlertDay(key: String, accountId: Long) = store.edit { remove(key + accountId) }

    fun stopPeriodRun(accountId: Long) = setAlertDay(
        KEY_PERIOD_DISMISSED, accountId, alertDay(KEY_PERIOD_ANCHOR, accountId)
    )

    companion object {
        const val NO_ACCOUNT = 0L
        const val NO_DAY = Long.MIN_VALUE
        const val KEY_PMS_DAY = "pms_day_"
        const val KEY_PERIOD_DAY = "period_day_"
        const val KEY_PERIOD_ANCHOR = "period_anchor_"
        const val KEY_PERIOD_DISMISSED = "period_dismissed_"
        private const val PREFS = "kiln_prefs"
        private const val KEY_DEFAULT = "default_account"
        private const val KEY_LOAD_DEFAULT = "load_default_on_start"

        @Volatile private var instance: KilnPrefs? = null
        fun get(context: Context): KilnPrefs =
            instance ?: synchronized(this) {
                instance ?: KilnPrefs(context).also { instance = it }
            }
    }
}