adds delete app data functionality

components/settings/data-management/delete-data-dialog.js

@@ -0,0 +1,19 @@
+import { Alert } from 'react-native'
+import { shared as sharedLabels } from '../../../i18n/en/labels'
+import labels from '../../../i18n/en/settings'
+
+export default function showDeleteDialog(okHandler) {
+
+  const { question, message, confirmation } = labels.deleteSegment
+
+  Alert.alert(
+    question,
+    message,
+    [{
+      text: confirmation,
+      onPress: okHandler
+    }, {
+      text: sharedLabels.cancel, style: 'cancel', onPress: () => { }
+    }]
+  )
+}

components/settings/data-management/delete-data.js

@@ -0,0 +1,126 @@
+import React, { Component } from 'react'
+import { View } from 'react-native'
+import nodejs from 'nodejs-mobile-react-native'
+import RNFS from 'react-native-fs'
+
+import settings from '../../../i18n/en/settings'
+import { requestHash, clearDb } from '../../../db'
+import { hasEncryptionObservable } from '../../../local-storage'
+import PasswordField from '../password/password-field'
+import SettingsButton from '../settings-button'
+import showDeleteDialog from './delete-data-dialog'
+import checkCurrentPassword from '../password/check-current-password'
+import alertError from '../alert-error'
+
+
+export default class DeleteData extends Component {
+  constructor() {
+    super()
+    this.state = {
+      isPasswordSet: hasEncryptionObservable.value,
+      currentPassword: null,
+      enteringCurrentPassword: false
+    }
+
+    nodejs.channel.addListener(
+      'pre-change-pw-check',
+      this.openNewPasswordField,
+      this
+    )
+  }
+
+  componentWillUnmount() {
+    nodejs.channel.removeListener('pre-change-pw-check', this.openNewPasswordField)
+  }
+
+  openNewPasswordField = async hash => {
+    const passwordCorrect = await checkCurrentPassword({
+      hash,
+      onTryAgain: () => this.setState({ currentPassword: null }),
+      onCancel: () => this.setState({
+        enteringCurrentPassword: false,
+        currentPassword: null
+      })
+    })
+
+    if (passwordCorrect) {
+      await this.deleteAppData()
+    }
+  }
+
+  startDataDeletion = () => {
+    showDeleteDialog(() => {
+      if (this.state.isPasswordSet) {
+        this.setState({ enteringCurrentPassword: true })
+      } else {
+        this.deleteAppData()
+      }
+    })
+  }
+
+  deleteExportedFile = async () => {
+    const path = RNFS.DocumentDirectoryPath + '/data.csv'
+    const isFileExist = await RNFS.exists(path)
+    if (isFileExist) {
+      await RNFS.unlink(path)
+    }
+  }
+
+  deleteAppData = async () => {
+    const { errors } = settings.deleteSegment
+    try {
+      await clearDb()
+      await this.deleteExportedFile()
+      this.props.onDeleteData()
+    } catch (err) {
+      return alertError(errors.couldNotDeleteFile)
+    }
+  }
+
+  handleCurrentPasswordInput = (currentPassword) => {
+    this.setState({ currentPassword })
+  }
+
+  checkCurrentPassword = () => {
+    requestHash('pre-change-pw-check', this.state.currentPassword)
+  }
+
+  render() {
+
+    const {
+      enteringCurrentPassword,
+      currentPassword
+    } = this.state
+
+    const labels = settings.passwordSettings
+
+    if (enteringCurrentPassword) {
+      return (
+        <View>
+          <PasswordField
+            placeholder={labels.enterCurrent}
+            value={currentPassword}
+            onChangeText={this.handleCurrentPasswordInput}
+          />
+          <SettingsButton
+            onPress={this.checkCurrentPassword}
+            disabled={!currentPassword}
+          >
+            {settings.deleteSegment.title}
+          </SettingsButton>
+        </View>
+      )
+    }
+
+    return (
+      <View>
+        <SettingsButton
+          onPress={this.startDataDeletion}
+          disabled={currentPassword}
+        >
+          {settings.deleteSegment.title}
+        </SettingsButton>
+      </View>
+    )
+  }
+}

components/settings/data-management/index.js

@@ -1,13 +1,27 @@
-import React from 'react'
+import React, { Component } from 'react'
 import { ScrollView } from 'react-native'
-import labels from '../../../i18n/en/settings'
 import AppText from '../../app-text'
 import SettingsSegment from '../settings-segment'
 import SettingsButton from '../settings-button'
 import openImportDialogAndImport from './import-dialog'
 import openShareDialogAndExport from './export-dialog'
+import { isDbEmpty } from '../../../db'
+import DeleteData from './delete-data'
+import labels from '../../../i18n/en/settings'
 
-const Settings = () => {
+class DataManagement extends Component {
+  constructor() {
+    super()
+    this.state = {
+      isDataEmpty: isDbEmpty()
+    }
+  }
+  onDeleteData = () => {
+    this.setState({
+      isDataEmpty: true
+    })
+  }
+  render() {
     return (
       <ScrollView>
         <SettingsSegment title={labels.export.button}>
@@ -22,14 +36,16 @@ const Settings = () => {
             {labels.import.button}
           </SettingsButton>
         </SettingsSegment>
+        {!isDbEmpty() && (
           <SettingsSegment title={labels.deleteSegment.title}>
             <AppText>{labels.deleteSegment.explainer}</AppText>
-        <SettingsButton onPress={openImportDialogAndImport}>
+            <DeleteData onDeleteData={this.onDeleteData} />
-          {labels.deleteSegment.title}
-        </SettingsButton>
           </SettingsSegment>
+        )}
       </ScrollView>
     )
+  }
 }
 
-export default Settings
+
+export default DataManagement

components/settings/password/index.js

@@ -8,7 +8,6 @@ import AppText from '../../app-text'
 import {
   hasEncryptionObservable
 } from '../../../local-storage'
-import styles from '../../../styles/index'
 import labels from '../../../i18n/en/settings'
 
 export default class PasswordSetting extends Component {

db/index.js

@@ -223,12 +223,22 @@ export async function changeEncryptionAndRestartApp(hash) {
   restart.Restart()
 }
 
+export function isDbEmpty () {
+  return db.empty
+}
+
 export async function deleteDbAndOpenNew() {
   const exists = await fs.exists(Realm.defaultPath)
   if (exists) await fs.unlink(Realm.defaultPath)
   await openDb()
 }
 
+export async function clearDb() {
+  await db.write(async () => {
+    await db.deleteAll()
+  })
+}
+
 function hashToInt8Array(hash) {
   const key = new Uint8Array(64)
   for (let i = 0; i < key.length; i++) {

i18n/en/settings.js

@@ -37,7 +37,14 @@ export default {
   },
   deleteSegment: {
     title: 'Delete app data',
-    explainer: 'Delete all app data from this phone'
+    explainer: 'Delete all app data from this phone',
+    question: 'Do you want to delete data from this phone?',
+    message: 'Please note that deletion of the data is permanent and irreversible. We recomend to export existing data before deletion.',
+    confirmation: 'Yes, I want to delete data permanently',
+    errors: {
+      couldNotDeleteFile: 'Could not delete file',
+      postFix: 'No data was deleted or changed'
+    }
   },
   tempScale: {
     segmentTitle: 'Temperature scale',