A DataStoreManager for local database in android working with dagger-hilt(DI).

DataStoreManager.kt

import android.content.Context
import androidx.datastore.preferences.core.*
import androidx.datastore.preferences.preferencesDataStore
import com.limeint.BuildConfig
import dagger.hilt.android.qualifiers.ApplicationContext
import kotlinx.coroutines.flow.Flow
import kotlinx.coroutines.flow.first
import kotlinx.coroutines.flow.map
import javax.inject.Inject
import javax.inject.Singleton

const val BEARER = "Bearer"
private val Context.dataStore by preferencesDataStore("settings")

@Singleton //You can ignore this annotation as return `datastore` from `preferencesDataStore` is singletone
class DataStoreManager @Inject constructor(@ApplicationContext appContext: Context) {

    private val mDataStore = appContext.dataStore


    companion object {
        //var context: Context? = null
        const val IS_PASSED_INTRO = "passedIntro"
        const val IS_LOGGED_IN = "loggedIn"
        const val USER_TOKEN = "userToken"
        const val LANGUAGE = "lang"
        const val IS_DARK = "isDark"
    }

    /**
     * for writing user token to datastore and mark user as logged in
     */
    suspend fun writeUserTokenAndMarkAsLoggedIn(userToken: String) {
        mDataStore.edit { settings ->
            settings[booleanPreferencesKey(IS_LOGGED_IN)] = true
            settings[stringPreferencesKey(USER_TOKEN)] = userToken
        }
    }

    /**
     * for reading user token from datastore
     */
    suspend fun readUserToken(): String {
        val bearer = BEARER
        val fakeToken = "eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJpc3MiOiJodHRwczpcL1wvbGltZWVpbnQuY29tXC9iYXNlXC9wdWJsaWNcL2FwaVwvYXV0aFwvbG9naW4iLCJpYXQiOjE2NDE3MTAwODQsImV4cCI6MTY3MzI0NjA4NCwibmJmIjoxNjQxNzEwMDg0LCJqdGkiOiI3Mkt5Tno1MUgzdHJTYUJGIiwic3ViIjozLCJwcnYiOiIyM2JkNWM4OTQ5ZjYwMGFkYjM5ZTcwMWM0MDA4NzJkYjdhNTk3NmY3In0.UbsWTkZCYWE1yNnOxLG7zPchi4-9iFvNIJYTeA46xpM"
        val token = if(BuildConfig.DEBUG) fakeToken else {
            mDataStore.data.map { settings ->
                settings[stringPreferencesKey(USER_TOKEN)] ?: ""
            }.first().toString()
        }
        return "$bearer $token"
    }

    suspend fun write(key: String, value: String) {
        mDataStore.edit { settings ->
            settings[stringPreferencesKey(key)] = value
        }
    }

    suspend fun read(key: String, defaultValue: String): String {
        return mDataStore.data.map { settings ->
            settings[stringPreferencesKey(key)] ?: defaultValue
        }.first().toString()
    }

    suspend fun write(key: String, value: Int) {
        mDataStore.edit { settings ->
            settings[intPreferencesKey(key)] = value
        }
    }

    suspend fun read(key: String, defaultValue: Int): Int {
        return mDataStore.data.map { settings ->
            settings[intPreferencesKey(key)] ?: defaultValue
        }.first().toInt()
    }

    suspend fun write(key: String, value: Double) {
        mDataStore.edit { settings ->
            settings[doublePreferencesKey(key)] = value
        }
    }

    suspend fun read(key: String, defaultValue: Double): Double {
        return mDataStore.data.map { settings ->
            settings[doublePreferencesKey(key)] ?: defaultValue
        }.first().toDouble()

    }

    suspend fun write(key: String, value: Boolean) {
        mDataStore.edit { settings ->
            settings[booleanPreferencesKey(key)] = value
        }
    }

    suspend fun read(key: String, defaultValue: Boolean): Boolean {
        return mDataStore.data.map { settings ->
            settings[booleanPreferencesKey(key)] ?: defaultValue
        }.first()

    }

    fun readTheme(key: String, defaultValue: Boolean): Flow<Boolean> {
        return mDataStore.data.map { settings ->
            settings[booleanPreferencesKey(key)] ?: defaultValue
        }

    }

    suspend fun clearDataStore() {
        mDataStore.edit { it.clear() }
    }

}