/* * This file is part of GNU Taler * (C) 2020 Taler Systems S.A. * * GNU Taler is free software; you can redistribute it and/or modify it under the * terms of the GNU General Public License as published by the Free Software * Foundation; either version 3, or (at your option) any later version. * * GNU Taler 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 General Public License for more details. * * You should have received a copy of the GNU General Public License along with * GNU Taler; see the file COPYING. If not, see */ package net.taler.merchantpos.config import android.content.Context import android.content.Context.MODE_PRIVATE import android.util.Base64.NO_WRAP import android.util.Base64.encodeToString import android.util.Log import androidx.annotation.UiThread import androidx.lifecycle.LiveData import androidx.lifecycle.MutableLiveData import com.android.volley.Request.Method.GET import com.android.volley.RequestQueue import com.android.volley.Response.ErrorListener import com.android.volley.Response.Listener import com.android.volley.VolleyError import com.android.volley.toolbox.JsonObjectRequest import com.fasterxml.jackson.databind.ObjectMapper import com.fasterxml.jackson.module.kotlin.readValue import kotlinx.coroutines.CoroutineScope import kotlinx.coroutines.Dispatchers import kotlinx.coroutines.launch import net.taler.merchantpos.R import org.json.JSONObject private const val SETTINGS_NAME = "taler-merchant-terminal" private const val SETTINGS_CONFIG_URL = "configUrl" private const val SETTINGS_USERNAME = "username" private const val SETTINGS_PASSWORD = "password" internal const val CONFIG_URL_DEMO = "https://docs.taler.net/_static/sample-pos-config.json" internal const val CONFIG_USERNAME_DEMO = "" internal const val CONFIG_PASSWORD_DEMO = "" private val TAG = ConfigManager::class.java.simpleName interface ConfigurationReceiver { /** * Returns null if the configuration was valid, or a error string for user display otherwise. */ suspend fun onConfigurationReceived(json: JSONObject, currency: String): String? } class ConfigManager( private val context: Context, private val scope: CoroutineScope, private val mapper: ObjectMapper, private val queue: RequestQueue ) { private val prefs = context.getSharedPreferences(SETTINGS_NAME, MODE_PRIVATE) private val configurationReceivers = ArrayList() var config = Config( configUrl = prefs.getString(SETTINGS_CONFIG_URL, CONFIG_URL_DEMO)!!, username = prefs.getString(SETTINGS_USERNAME, CONFIG_USERNAME_DEMO)!!, password = prefs.getString(SETTINGS_PASSWORD, CONFIG_PASSWORD_DEMO)!! ) var merchantConfig: MerchantConfig? = null private set private val mConfigUpdateResult = MutableLiveData() val configUpdateResult: LiveData = mConfigUpdateResult fun addConfigurationReceiver(receiver: ConfigurationReceiver) { configurationReceivers.add(receiver) } @UiThread fun fetchConfig(config: Config, save: Boolean, savePassword: Boolean = false) { mConfigUpdateResult.value = null val configToSave = if (save) { if (savePassword) config else config.copy(password = "") } else null val stringRequest = object : JsonObjectRequest(GET, config.configUrl, null, Listener { onConfigReceived(it, configToSave) }, ErrorListener { onNetworkError(it) } ) { // send basic auth header override fun getHeaders(): MutableMap { val credentials = "${config.username}:${config.password}" val auth = ("Basic ${encodeToString(credentials.toByteArray(), NO_WRAP)}") return mutableMapOf("Authorization" to auth) } } queue.add(stringRequest) } @UiThread private fun onConfigReceived(json: JSONObject, config: Config?) { val merchantConfig: MerchantConfig = try { mapper.readValue(json.getString("config")) } catch (e: Exception) { Log.e(TAG, "Error parsing merchant config", e) val msg = context.getString(R.string.config_error_malformed) mConfigUpdateResult.value = ConfigUpdateResult.Error(msg) return } val params = mapOf("instance" to merchantConfig.instance) val req = MerchantRequest(GET, merchantConfig, "config", params, null, Listener { onMerchantConfigReceived(config, json, merchantConfig, it) }, ErrorListener { onNetworkError(it) } ) queue.add(req) } private fun onMerchantConfigReceived( newConfig: Config?, configJson: JSONObject, merchantConfig: MerchantConfig, json: JSONObject ) = scope.launch(Dispatchers.Default) { val currency = json.getString("currency") for (receiver in configurationReceivers) { val result = try { receiver.onConfigurationReceived(configJson, currency) } catch (e: Exception) { Log.e(TAG, "Error handling configuration by ${receiver::class.java.simpleName}", e) context.getString(R.string.config_error_unknown) } if (result != null) { // error mConfigUpdateResult.postValue(ConfigUpdateResult.Error(result)) return@launch } } newConfig?.let { config = it saveConfig(it) } this@ConfigManager.merchantConfig = merchantConfig.copy(currency = currency) mConfigUpdateResult.postValue(ConfigUpdateResult.Success(currency)) } fun forgetPassword() { config = config.copy(password = "") saveConfig(config) merchantConfig = null } private fun saveConfig(config: Config) { prefs.edit() .putString(SETTINGS_CONFIG_URL, config.configUrl) .putString(SETTINGS_USERNAME, config.username) .putString(SETTINGS_PASSWORD, config.password) .apply() } @UiThread private fun onNetworkError(it: VolleyError?) { val msg = context.getString( if (it?.networkResponse?.statusCode == 401) R.string.config_auth_error else R.string.config_error_network ) mConfigUpdateResult.value = ConfigUpdateResult.Error(msg) } } sealed class ConfigUpdateResult { data class Error(val msg: String) : ConfigUpdateResult() data class Success(val currency: String) : ConfigUpdateResult() }