// SPDX-License-Identifier: GPL-3.0-only
package no.naiv.implausibly.data

import android.content.Context
import androidx.datastore.core.DataStore
import androidx.datastore.preferences.core.Preferences
import androidx.datastore.preferences.core.edit
import androidx.datastore.preferences.core.stringPreferencesKey
import androidx.datastore.preferences.preferencesDataStore
import dagger.hilt.android.qualifiers.ApplicationContext
import kotlinx.coroutines.flow.Flow
import kotlinx.coroutines.flow.map
import javax.inject.Inject
import javax.inject.Singleton

private val Context.dataStore: DataStore<Preferences> by preferencesDataStore(
    name = "implausibly_preferences"
)

/**
 * Non-sensitive preferences stored via DataStore.
 * Includes the user's selected instance, site, and date range.
 */
@Singleton
class AppPreferences @Inject constructor(
    @ApplicationContext private val context: Context
) {
    private object Keys {
        val SELECTED_INSTANCE_ID = stringPreferencesKey("selected_instance_id")
        val SELECTED_SITE_ID = stringPreferencesKey("selected_site_id")
        val SELECTED_DATE_RANGE = stringPreferencesKey("selected_date_range")
    }

    val selectedInstanceId: Flow<String?> = context.dataStore.data
        .map { it[Keys.SELECTED_INSTANCE_ID] }

    val selectedSiteId: Flow<String?> = context.dataStore.data
        .map { it[Keys.SELECTED_SITE_ID] }

    val selectedDateRange: Flow<String?> = context.dataStore.data
        .map { it[Keys.SELECTED_DATE_RANGE] }

    suspend fun setSelectedInstanceId(id: String?) {
        context.dataStore.edit { prefs ->
            if (id != null) prefs[Keys.SELECTED_INSTANCE_ID] = id
            else prefs.remove(Keys.SELECTED_INSTANCE_ID)
        }
    }

    suspend fun setSelectedSiteId(id: String?) {
        context.dataStore.edit { prefs ->
            if (id != null) prefs[Keys.SELECTED_SITE_ID] = id
            else prefs.remove(Keys.SELECTED_SITE_ID)
        }
    }

    suspend fun setSelectedDateRange(range: String) {
        context.dataStore.edit { prefs ->
            prefs[Keys.SELECTED_DATE_RANGE] = range
        }
    }
}