save grades to a encrypted cache file, use cache if not older than 24hr

app/build.gradle

@@ -51,7 +51,7 @@ dependencies {
     implementation 'androidx.core:core:1.3.1'
     implementation 'androidx.appcompat:appcompat:1.2.0'
     implementation 'androidx.legacy:legacy-support-v4:1.0.0'
-    implementation 'androidx.constraintlayout:constraintlayout:2.0.0'
+    implementation 'androidx.constraintlayout:constraintlayout:2.0.1'
     implementation 'androidx.swiperefreshlayout:swiperefreshlayout:1.1.0'
     implementation 'androidx.security:security-crypto:1.1.0-alpha02'
     implementation 'com.google.android.material:material:1.2.0'
@@ -66,7 +66,7 @@ dependencies {
     implementation 'org.jsoup:jsoup:1.13.1'
 
     testImplementation 'junit:junit:4.13'
-    androidTestImplementation 'androidx.test:core:1.2.0'
+    androidTestImplementation 'androidx.test:core:1.3.0'
     androidTestImplementation 'androidx.test.ext:junit:1.1.1'
 }
 

app/src/main/java/org/mosad/seil0/projectlaogai/controller/cache/CacheController.kt

@@ -24,21 +24,26 @@ package org.mosad.seil0.projectlaogai.controller.cache
 
 import android.content.Context
 import android.util.Log
+import androidx.security.crypto.EncryptedFile
+import androidx.security.crypto.MasterKey
 import com.google.gson.Gson
 import com.google.gson.GsonBuilder
 import com.google.gson.JsonParser
 import com.google.gson.reflect.TypeToken
 import kotlinx.coroutines.*
+import org.mosad.seil0.projectlaogai.controller.QISPOSParser
 import org.mosad.seil0.projectlaogai.controller.preferences.Preferences
 import org.mosad.seil0.projectlaogai.controller.TCoRAPIController
 import org.mosad.seil0.projectlaogai.controller.preferences.Preferences.cCourse
 import org.mosad.seil0.projectlaogai.controller.preferences.Preferences.coursesCacheTime
+import org.mosad.seil0.projectlaogai.controller.preferences.Preferences.gradesCacheTime
 import org.mosad.seil0.projectlaogai.controller.preferences.Preferences.mensaCacheTime
 import org.mosad.seil0.projectlaogai.controller.preferences.Preferences.timetableCacheTime
 import org.mosad.seil0.projectlaogai.util.*
 import java.io.*
 import java.util.*
 import kotlin.collections.ArrayList
+import kotlin.collections.HashMap
 
 /**
  * The cacheController reads and updates the cache files.
@@ -201,6 +206,25 @@ class CacheController(cont: Context) {
             }
         }
 
+        /**
+         * update the encrypted grades file
+         */
+        fun updateGrades(context: Context): Job {
+            val file = File(context.filesDir, "grades_encrypted")
+            val parser = QISPOSParser(context)
+
+            return GlobalScope.launch(Dispatchers.IO) {
+                if (parser.checkQISPOSStatus() == 200) {
+                    if (file.exists()) { file.delete() }
+
+                    // save cache file and update time
+                    saveEncrypted(context, file, Gson().toJson(parser.parseGrades()))
+                    gradesCacheTime = System.currentTimeMillis() / 1000
+                    Preferences.save(context)
+                }
+            }
+        }
+
         /**
          * save changes in lessonMap and subjectMap,
          * called on addSubject or removeSubject
@@ -223,6 +247,22 @@ class CacheController(cont: Context) {
             }
         }
 
+        private fun saveEncrypted(context: Context, file: File, text: String) {
+            val masterKey = MasterKey.Builder(context)
+                .setKeyScheme(MasterKey.KeyScheme.AES256_GCM)
+                .build()
+            val encryptedFile = EncryptedFile.Builder(
+                context,
+                file,
+                masterKey,
+                EncryptedFile.FileEncryptionScheme.AES256_GCM_HKDF_4KB
+            ).build()
+
+            encryptedFile.openFileOutput().bufferedWriter().use {
+                it.write(text)
+            }
+        }
+
     }
 
     /**
@@ -372,4 +412,40 @@ class CacheController(cont: Context) {
 
     }
 
+    /**
+     * read the encrypted grades file, don't keep them
+     * in CacheController for security reasons
+     * @return the grades as HashMap if the file exists, else a empty HashMap
+     */
+    fun readGrades(): HashMap<String, ArrayList<GradeSubject>> {
+        val file = File(context.filesDir, "grades_encrypted")
+
+        // if the file does not exit, try creating it
+        if (!file.exists()) {
+            runBlocking { updateGrades(context) }
+        }
+
+        if (file.exists()) {
+            val masterKey = MasterKey.Builder(context)
+                .setKeyScheme(MasterKey.KeyScheme.AES256_GCM)
+                .build()
+            val encryptedFile = EncryptedFile.Builder(
+                context,
+                file,
+                masterKey,
+                EncryptedFile.FileEncryptionScheme.AES256_GCM_HKDF_4KB
+            ).build()
+
+            return encryptedFile.openFileInput().bufferedReader().use {
+                GsonBuilder().create()
+                    .fromJson(
+                        it.readLine(),
+                        object : TypeToken<HashMap<String, ArrayList<GradeSubject>>>() {}.type
+                    )
+            }
+        }
+
+        return HashMap()
+    }
+
 }

app/src/main/java/org/mosad/seil0/projectlaogai/controller/cache/TimetableController.kt

@@ -38,94 +38,91 @@ import org.mosad.seil0.projectlaogai.util.TimetableWeek
  *  * add second week
  *  * add configurable week to addSubject() and removeSubject(), updateAdditionalLessons()
  */
-class TimetableController {
+object TimetableController {
 
-    companion object {
-        val timetable = ArrayList<TimetableWeek>()
-        val lessonMap = HashMap<String, Lesson>() // the key is courseName-subject-lessonID
-        val subjectMap = HashMap<String, ArrayList<String>>() // the key is courseName
+    val timetable = ArrayList<TimetableWeek>()
+    val lessonMap = HashMap<String, Lesson>() // the key is courseName-subject-lessonID
+    val subjectMap = HashMap<String, ArrayList<String>>() // the key is courseName
 
-        /**
-         * update the main timetable and all additional subjects, async
-         */
-        fun update(context: Context): List<Job> {
-            return listOf(
-                CacheController.updateTimetable(cCourse.courseName, 0, context),
-                CacheController.updateTimetable(cCourse.courseName, 1, context),
-                CacheController.updateAdditionalLessons(context)
-            )
+    /**
+     * update the main timetable and all additional subjects, async
+     */
+    fun update(context: Context): List<Job> {
+        return listOf(
+            CacheController.updateTimetable(cCourse.courseName, 0, context),
+            CacheController.updateTimetable(cCourse.courseName, 1, context),
+            CacheController.updateAdditionalLessons(context)
+        )
+    }
+
+    /**
+     * add a subject to the subjectMap and all it's lessons
+     * to the lessonMap
+     * @param courseName course to which the subject belongs
+     * @param subject the subjects name
+     */
+    fun addSubject(courseName: String, subject: String, context: Context) {
+        // add subject
+        if (subjectMap.containsKey(courseName)) {
+            subjectMap[courseName]?.add(subject)
+        } else {
+            subjectMap[courseName] = arrayListOf(subject)
         }
 
-        /**
-         * add a subject to the subjectMap and all it's lessons
-         * to the lessonMap
-         * @param courseName course to which the subject belongs
-         * @param subject the subjects name
-         */
-        fun addSubject(courseName: String, subject: String, context: Context) {
-            // add subject
-            if (subjectMap.containsKey(courseName)) {
-                subjectMap[courseName]?.add(subject)
-            } else {
-                subjectMap[courseName] = arrayListOf(subject)
+        // add concrete lessons
+        TCoRAPIController.getLessons(courseName, subject, 0).forEach { lesson ->
+            addLesson(courseName, subject, lesson)
+        }
+
+        CacheController.saveAdditionalSubjects(context)
+    }
+
+    /**
+     * remove a subject from the subjectMap and all it's lessons
+     * from the lessonMap
+     * @param courseName course to which the subject belongs
+     * @param subject the subjects name
+     */
+    fun removeSubject(courseName: String, subject: String, context: Context) {
+        // remove subject
+        subjectMap[courseName]?.remove(subject)
+
+        // remove concrete lessons
+        val iterator = lessonMap.iterator()
+        while (iterator.hasNext()) {
+            val it = iterator.next()
+            if(it.key.contains("$courseName-$subject")) {
+                // remove the lesson from the lessons list
+                iterator.remove() // use iterator to remove, otherwise ConcurrentModificationException
+
+                // remove the lesson from the timetable
+                val id = it.value.lessonID.split(".")
+                if(id.size == 3)
+                    timetable[0].days[id[0].toInt()].timeslots[id[1].toInt()].remove(it.value)
             }
-
-            // add concrete lessons
-            TCoRAPIController.getLessons(courseName, subject, 0).forEach { lesson ->
-                addLesson(courseName, subject, lesson)
-            }
-
-            CacheController.saveAdditionalSubjects(context)
         }
 
-        /**
-         * remove a subject from the subjectMap and all it's lessons
-         * from the lessonMap
-         * @param courseName course to which the subject belongs
-         * @param subject the subjects name
-         */
-        fun removeSubject(courseName: String, subject: String, context: Context) {
-            // remove subject
-            subjectMap[courseName]?.remove(subject)
+        CacheController.saveAdditionalSubjects(context)
+    }
 
-            // remove concrete lessons
-            val iterator = lessonMap.iterator()
-            while (iterator.hasNext()) {
-                val it = iterator.next()
-                if(it.key.contains("$courseName-$subject")) {
-                    // remove the lesson from the lessons list
-                    iterator.remove() // use iterator to remove, otherwise ConcurrentModificationException
+    /**
+     * add a lesson to the lessonMap, also add it to the timetable
+     */
+    fun addLesson(courseName: String, subject: String, lesson: Lesson) {
+        //the courseName, subject and lessonID, separator: -
+        val key = "$courseName-$subject-${lesson.lessonID}"
+        lessonMap[key] = lesson
 
-                    // remove the lesson from the timetable
-                    val id = it.value.lessonID.split(".")
-                    if(id.size == 3)
-                        timetable[0].days[id[0].toInt()].timeslots[id[1].toInt()].remove(it.value)
-                }
-            }
-
-            CacheController.saveAdditionalSubjects(context)
-        }
-
-        /**
-         * add a lesson to the lessonMap, also add it to the timetable
-         */
-        fun addLesson(courseName: String, subject: String, lesson: Lesson) {
-            //the courseName, subject and lessonID, separator: -
-            val key = "$courseName-$subject-${lesson.lessonID}"
-            lessonMap[key] = lesson
-
-            addLessonToTimetable(lesson)
-        }
-
-        /**
-         * add a lesson to the timetable
-         */
-        fun addLessonToTimetable(lesson: Lesson) {
-            val id = lesson.lessonID.split(".")
-            if(id.size == 3)
-                timetable[0].days[id[0].toInt()].timeslots[id[1].toInt()].add(lesson)
-        }
+        addLessonToTimetable(lesson)
+    }
 
+    /**
+     * add a lesson to the timetable
+     */
+    fun addLessonToTimetable(lesson: Lesson) {
+        val id = lesson.lessonID.split(".")
+        if(id.size == 3)
+            timetable[0].days[id[0].toInt()].timeslots[id[1].toInt()].add(lesson)
     }
 
 }

app/src/main/java/org/mosad/seil0/projectlaogai/controller/preferences/Preferences.kt

@@ -36,6 +36,7 @@ object Preferences {
     var coursesCacheTime: Long = 0
     var mensaCacheTime: Long = 0
     var timetableCacheTime: Long = 0
+    var gradesCacheTime: Long = 0
     var cColorPrimary: Int = Color.parseColor("#009688")
     var cColorAccent: Int = Color.parseColor("#0096ff")
     var cCourse = Course(
@@ -67,6 +68,9 @@ object Preferences {
             putLong(context.getString(R.string.save_key_timetableCacheTime),
                 timetableCacheTime
             )
+            putLong(context.getString(R.string.save_key_gradesCacheTime),
+                gradesCacheTime
+            )
             apply()
         }
 
@@ -166,6 +170,9 @@ object Preferences {
         timetableCacheTime = sharedPref.getLong(context.getString(
                 R.string.save_key_timetableCacheTime
             ), 0)
+        gradesCacheTime = sharedPref.getLong(context.getString(
+            R.string.save_key_gradesCacheTime
+        ), 0)
 
         // load saved course
         cCourse = Course(

app/src/main/java/org/mosad/seil0/projectlaogai/fragments/GradesFragment.kt

@@ -35,11 +35,13 @@ import kotlinx.android.synthetic.main.fragment_grades.*
 import kotlinx.coroutines.*
 import org.mosad.seil0.projectlaogai.R
 import org.mosad.seil0.projectlaogai.controller.QISPOSParser
+import org.mosad.seil0.projectlaogai.controller.cache.CacheController
 import org.mosad.seil0.projectlaogai.controller.preferences.EncryptedPreferences
 import org.mosad.seil0.projectlaogai.controller.preferences.Preferences
 import org.mosad.seil0.projectlaogai.uicomponents.DayCardView
 import org.mosad.seil0.projectlaogai.uicomponents.GradeLinearLayout
 import org.mosad.seil0.projectlaogai.uicomponents.dialogs.LoginDialog
+import kotlin.system.measureTimeMillis
 
 /**
  * The grades fragment class
@@ -64,6 +66,7 @@ class GradesFragment : Fragment() {
 
         parser = QISPOSParser(context!!)// init the parser
 
+        // TODO if loading from cache, don't check Qispos state
         if (checkCredentials() && checkQisposStatus()) {
             GlobalScope.launch(Dispatchers.Default) {
                 addGrades()
@@ -125,76 +128,89 @@ class GradesFragment : Fragment() {
         return statusCode == 200
     }
 
-    // add the grades to the layout, async
+    /**
+     * add the grades to the layout, async
+     * TODO this is slow as hell
+     */
     private fun addGrades() = GlobalScope.launch(Dispatchers.Default) {
-        withContext(Dispatchers.Main) {
-            refreshLayout_Grades.isRefreshing = true
-        }
+        val addGradesTime = measureTimeMillis {
 
-        val grades = parser.parseGrades()
-
-        withContext(Dispatchers.Main) {
-            linLayout_Grades.removeAllViews() // clear layout
-        }
-
-        // for each semester add a new card
-        grades.forEach { semester ->
-            val usedSubjects = ArrayList<String>()
-            val semesterCard = DayCardView(context!!)
-            semesterCard.setDayHeading(semester.key)
-
-            // for each subject add a new linLayout
-            semester.value.forEachIndexed { index, subject ->
-                if (usedSubjects.contains(subject.name)) {
-                    return@forEachIndexed
-                }
-
-                // get the first sub subjects
-                val subSubject = semester.value.firstOrNull {
-                    it.name.contains(subject.name) && it.name != subject.name
-                }
-
-                // if sub subject is not null, add it to used subjects
-                subSubject?.let {
-                    usedSubjects.add(it.name)
-                }
-
-                val subjectLayout = GradeLinearLayout(context).set {
-                    subjectName = subject.name
-                    grade = subject.grade
-                    subSubjectName = subSubject?.name.toString()
-                    subGrade = subSubject?.grade.toString()
-                }
-
-                // disable sub-subject if not set
-                if (subSubject == null)
-                    subjectLayout.disableSubSubject()
-
-                // disable divider if last element
-                if (index == semester.value.lastIndex || semester.value.indexOf(subSubject) == semester.value.lastIndex)
-                    subjectLayout.disableDivider()
-
-                semesterCard.getLinLayoutDay().addView(subjectLayout)
-            }
-
-            // without context we can't access the view
             withContext(Dispatchers.Main) {
-                linLayout_Grades.addView(semesterCard)
+                refreshLayout_Grades.isRefreshing = true
             }
+
+            // if the cache is older than 24hr, update blocking
+            val currentTime = System.currentTimeMillis() / 1000
+            if ((currentTime - Preferences.gradesCacheTime) > 86400) {
+                CacheController.updateGrades(context!!).join()
+            }
+
+            val grades = CacheController(context!!).readGrades()
+
+            withContext(Dispatchers.Main) {
+                linLayout_Grades.removeAllViews() // clear layout
+            }
+
+            // TODO this loop takes 3/4 of the time
+            // for each semester add a new card
+            grades.forEach { semester ->
+                val usedSubjects = ArrayList<String>()
+                val semesterCard = DayCardView(context!!)
+                semesterCard.setDayHeading(semester.key)
+
+                // for each subject add a new linLayout
+                semester.value.forEachIndexed { index, subject ->
+                    if (usedSubjects.contains(subject.name)) {
+                        return@forEachIndexed
+                    }
+
+                    // get the first sub subjects
+                    val subSubject = semester.value.firstOrNull {
+                        it.name.contains(subject.name) && it.name != subject.name
+                    }
+
+                    // if sub subject is not null, add it to used subjects
+                    subSubject?.let {
+                        usedSubjects.add(it.name)
+                    }
+
+                    val subjectLayout = GradeLinearLayout(context).set {
+                        subjectName = subject.name
+                        grade = subject.grade
+                        subSubjectName = subSubject?.name.toString()
+                        subGrade = subSubject?.grade.toString()
+                    }
+
+                    // disable sub-subject if not set
+                    if (subSubject == null)
+                        subjectLayout.disableSubSubject()
+
+                    // disable divider if last element
+                    if (index == semester.value.lastIndex || semester.value.indexOf(subSubject) == semester.value.lastIndex)
+                        subjectLayout.disableDivider()
+
+                    semesterCard.getLinLayoutDay().addView(subjectLayout)
+                }
+
+                // without context we can't access the view
+                withContext(Dispatchers.Main) {
+                    linLayout_Grades.addView(semesterCard)
+                }
+            }
+
+            val txtViewLegal = TextView(context).apply {
+                text = resources.getString(R.string.without_guarantee)
+                textAlignment = View.TEXT_ALIGNMENT_CENTER
+            }
+
+            // stop refreshing and show legal warning
+            withContext(Dispatchers.Main) {
+                linLayout_Grades.addView(txtViewLegal)
+                refreshLayout_Grades.isRefreshing = false
+            }
+
         }
-
-
-
-        val txtViewLegal = TextView(context).apply {
-            text = resources.getString(R.string.without_guarantee)
-            textAlignment = View.TEXT_ALIGNMENT_CENTER
-        }
-
-        // stop refreshing and show legal warning
-        withContext(Dispatchers.Main) {
-            linLayout_Grades.addView(txtViewLegal)
-            refreshLayout_Grades.isRefreshing = false
-        }
+        println("startup completed in $addGradesTime ms")
     }
 
 }

app/src/main/java/org/mosad/seil0/projectlaogai/fragments/TimeTableFragment.kt

@@ -33,7 +33,7 @@ import kotlinx.android.synthetic.main.fragment_timetable.*
 import kotlinx.coroutines.*
 import org.mosad.seil0.projectlaogai.R
 import org.mosad.seil0.projectlaogai.controller.cache.TimetableController
-import org.mosad.seil0.projectlaogai.controller.cache.TimetableController.Companion.timetable
+import org.mosad.seil0.projectlaogai.controller.cache.TimetableController.timetable
 import org.mosad.seil0.projectlaogai.controller.preferences.Preferences
 import org.mosad.seil0.projectlaogai.uicomponents.dialogs.AddSubjectDialog
 import org.mosad.seil0.projectlaogai.uicomponents.DayCardView

app/src/main/res/values/strings.xml

@@ -127,6 +127,7 @@
     <string name="save_key_coursesCacheTime" translatable="false">org.mosad.seil0.projectlaogai.coursesCacheTime</string>
     <string name="save_key_mensaCacheTime" translatable="false">org.mosad.seil0.projectlaogai.mensaCacheTime</string>
     <string name="save_key_timetableCacheTime" translatable="false">org.mosad.seil0.projectlaogai.timetableCacheTime</string>
+    <string name="save_key_gradesCacheTime" translatable="false">org.mosad.seil0.projectlaogai.gradesCacheTime</string>
     <string name="save_key_user_email" translatable="false">org.mosad.seil0.projectlaogai.user_email</string>
     <string name="save_key_user_password" translatable="false">org.mosad.seil0.projectlaogai.user_password</string>