Fix #159: Introduce question player UI structure (#500)

* Initial check in for the question data controller

* Removed progress controller test

* Address the renames suggested in #217.

* Introduce thoroughly stubbed QuestionAssessmentProgressController +
empty test suite.

* Review changes

* Review changes

* Pass data providers to the assessment controller, and set caps in the training controller

* Removed unnecessary imports/variables

* Add fake question data for stubbed interfaces

* Remove duplicate questions while fetching in training controller

* Comment explaining the filter function

* Improve duplicate checking - check it while filtering instead of after filtering

* Add linked skill id values

* Review changes

* add a new module for questions constants

* Review changes

* add a test to verify questions were fetched properly

* reformatted code

* Re-add QuestionTrainingController removed in merge.

* Finalize question progress controller interface.

* Implement QuestionAssessmentProgressController.

This includes some basic refactoring of internal structures used by the
exploration progress controller to share common functionality between the
two progress controllers. There's still some duplication, but this seems
like a reasonable split since there's likely to be further differences in
the progress controllers in the future.

The question assessment progress controller tests pass, but no new ones
have yet been added to thoroughly test the implementation.

* Add initial phase of tests for the progress controller based on
ExplorationProgressController. They haven't yet been verified as correct.

* Fix typo in QuestionTrainingController.

* Post-merge fixes and adjustments.

* Fix broken ProfileManagementControllerTest.

* Post-merge fixes.

* Update tests to build, but not pass.

* Started UI

* setup ViewModel

* added binding adapter

* Handles basic functionality

* Moved code around

* Added replay button

* Make questions partially work.

This introduces back button behavior to ensure training sessions can be
reset.

This also attempts to introduce proper asset loading, but it doesn't
seem to be working currently.

* Temporarily remove check in StateDeck that breaks questions.

* Ensure all state navigation buttons are on the same line and the same
size.

This required reworking how nav button binding works in the state
fragment such that multiple models are used depending on which type of
navigation scenario the fragment is currently in.

* Fix dp adjustment that caused previous button to disappear.

Fix previous button showing up twice for continue interaction.

* Undo .idea/misc.xml change that snuck in.

* Update & fix StateFragmentTest (at least for Espresso). See #495 description
for details on the changes necessary to make these tests work.

* Post-merge fixes with some temporary stop-gap solutions.

* Fix questions image rendering and consolidate GCS resource bucket names.

* Fix question session not properly being reinitialized for new sessions.

Also, ensure that notifications do not regenerate the training session.

* Fix index accounting for questions. Before, the index incremented upon
correct answer submission rather than navigation.

* Remove support for backward navigation in questions since it isn't
allowed.

* Set title of question activity to 'Train Mode'.

* Add support for a synthetic ephemeral question to represent the end of a
training session.

* Update question progress tracking to be translatable and to ensure that
the synthetic terminal state shows the correct progress: 'completed'.

* Move most state player functional support into a new configurable
assembler class to enable sharing between the exploration and question
players.

* Hook up StatePlayerRecyclerViewAssembler to the question player fragment
presenter. This also enables the congratulations text.

* Introduce proper terminal page and disable overscroll. Note that the end
session page introduced here has not been mocked yet, so it's mostly a
placeholder until a mock is available.

* Add support & button for training session replay.

* Update/add TODOs to correspond to GitHub tracked issues.

* Fix broken import.

* Finish tests for Question{Training,AssessmentProgress}Controllers.

Note that the nature of the assessment progress controller is such that
a new, dynamic DataProvider is needed since the data provider for the
current assessment question is actually a transformation of different
data providers depending on which questions are passed to the
controller.

* Initial introduction of test coroutine dispatchers to replace Kotlin's
test coroutine dispatcher.

This includes introducing a test-only module to contain testing
dependencies.

* Introduce a new LiveData mechanism to bridge coroutines from
DataProviders in a way that doesn't have the same limitations as the
previous MutableLiveData-based bridge.

* Introduce new nested data provider that effectively allows a
DataProvider to be set up like transformAsync() but with the ability to
change the root DataProvider.

* question player progress-bar hifi

* nit

* revert

* revert

* Early work at introducing FakeSystemClock tests (not yet complete).

* Post-merge fixes.

* Fix the submit button disabled states: with the new refactor, the submit
button is now properly disabled when an invalid answer is pending.

* Revert accidental changes to .idea/misc.xml.

* Address reviewer comments.

* Remove unnecessary meta file for Mockito.

* Minor import cleanup.

* Post-merge fixes.

* Fix audio playback & generalize it to facilitate enabling it for
questions in the future.

* Address reviewer comments & fix broken tests.

* Fix hints & solutions functionality after simplification (some bugs &
regressions were introduced due to the simplification; these have been
fixed).

* Revert the assembler delays to match the intended durations rather than
the test-only values used for development.

* Address reviewer comments.

* Remove infeasible testing structures, add documentation, and clean up
implementation to prepare for code review.

* Add notice that the dispatchers utility is temporary.

* Cleanup new LiveData bridge, add tests for it, and migrate other
DataProviders tests to using TestCoroutineDispatchers utility.

* Add AsyncResult tests, fix & re-enable an earlier test in PersistentCacheStoreTest, and fix FakeSystemClock so that it works properly in test environments.

* Use ktlint to reformat TestCoroutineDispatchers per reviewer comment
thread.

* Reformat files failing linter check.

* Reformat new DataProviders code.

* Add new tests for the NestedTransformedDataProvider.

* Address reviewer comment.

* Address reviewer comments.

* Address reviewer comments & fix lint issue.

* Update hints & solutions handling to more closely follow the intended
behavior graph (and added an actual visual representation of this graph
in code to simplify maintaining the solution in the future). Tests will
be added as part of solving #1273.

Co-authored-by: vinitamurthi <[email protected]>
Co-authored-by: James Xu <[email protected]>
Co-authored-by: marysoloman <[email protected]>

app/src/main/AndroidManifest.xml

@@ -139,7 +139,8 @@
       android:theme="@style/OppiaThemeWithoutActionBar" />
     <activity
       android:name=".topic.questionplayer.QuestionPlayerActivity"
-      android:screenOrientation="portrait" />
+      android:screenOrientation="portrait"
+      android:label="@string/question_player_title" />
     <activity
       android:name=".topic.revisioncard.RevisionCardActivity"
       android:theme="@style/OppiaThemeWithoutActionBar" />

app/src/main/java/org/oppia/app/application/ApplicationComponent.kt

@@ -14,6 +14,7 @@ import org.oppia.domain.classify.rules.multiplechoiceinput.MultipleChoiceInputMo
 import org.oppia.domain.classify.rules.numberwithunits.NumberWithUnitsRuleModule
 import org.oppia.domain.classify.rules.numericinput.NumericInputRuleModule
 import org.oppia.domain.classify.rules.textinput.TextInputRuleModule
+import org.oppia.domain.question.QuestionModule
 import org.oppia.util.caching.CachingModule
 import org.oppia.util.gcsresource.GcsResourceModule
 import org.oppia.util.logging.LoggerModule
@@ -28,10 +29,11 @@ import javax.inject.Singleton
 @Singleton
 @Component(modules = [
   ApplicationModule::class, DispatcherModule::class, NetworkModule::class, LoggerModule::class,
-  ContinueModule::class, FractionInputModule::class, ItemSelectionInputModule::class, MultipleChoiceInputModule::class,
-  NumberWithUnitsRuleModule::class, NumericInputRuleModule::class, TextInputRuleModule::class,
-  DragDropSortInputModule::class, InteractionsModule::class, GcsResourceModule::class, GlideImageLoaderModule::class,
-  ImageParsingModule::class, HtmlParserEntityTypeModule::class, CachingModule::class
+  ContinueModule::class, FractionInputModule::class, ItemSelectionInputModule::class,
+  MultipleChoiceInputModule::class, NumberWithUnitsRuleModule::class, NumericInputRuleModule::class,
+  TextInputRuleModule::class, DragDropSortInputModule::class, InteractionsModule::class,
+  GcsResourceModule::class, GlideImageLoaderModule::class, ImageParsingModule::class,
+  HtmlParserEntityTypeModule::class, CachingModule::class, QuestionModule::class
 ])
 interface ApplicationComponent {
   @Component.Builder

app/src/main/java/org/oppia/app/player/audio/AudioFragment.kt

@@ -62,6 +62,16 @@ class AudioFragment : InjectableFragment(), LanguageInterface, AudioUiManager,
     audioFragmentPresenter.handleOnDestroy()
   }
 
+  override fun enableAudioPlayback(contentId: String?) {
+    audioFragmentPresenter.handleAudioClick(
+      shouldEnableAudioPlayback = true, feedbackId = contentId
+    )
+  }
+
+  override fun disableAudioPlayback() {
+    audioFragmentPresenter.handleAudioClick(shouldEnableAudioPlayback = false, feedbackId = null)
+  }
+
   override fun setStateAndExplorationId(newState: State, explorationId: String) =
     audioFragmentPresenter.setStateAndExplorationId(newState, explorationId)
 
@@ -86,7 +96,4 @@ class AudioFragment : InjectableFragment(), LanguageInterface, AudioUiManager,
 
   /** Used in data binding to know position of user's touch */
   fun getUserPosition() = audioFragmentPresenter.userProgress
-
-  fun handleAudioClick(isShowing: Boolean, feedbackId: String?) =
-    audioFragmentPresenter.handleAudioClick(isShowing, feedbackId)
 }

app/src/main/java/org/oppia/app/player/audio/AudioFragmentPresenter.kt

@@ -196,11 +196,9 @@ class AudioFragmentPresenter @Inject constructor(
     }
   }
 
-  fun handleAudioClick(isShowing: Boolean, feedbackId: String?) {
+  fun handleAudioClick(shouldEnableAudioPlayback: Boolean, feedbackId: String?) {
     this.feedbackId = feedbackId
-    if (isShowing) {
-      setAudioFragmentVisible(false)
-    } else {
+    if (shouldEnableAudioPlayback) {
       when (networkConnectionUtil.getCurrentConnectionStatus()) {
         NetworkConnectionUtil.ConnectionStatus.LOCAL -> setAudioFragmentVisible(true)
         NetworkConnectionUtil.ConnectionStatus.CELLULAR -> {
@@ -220,6 +218,8 @@ class AudioFragmentPresenter @Inject constructor(
           setAudioFragmentVisible(false)
         }
       }
+    } else {
+      setAudioFragmentVisible(false)
     }
   }
 

app/src/main/java/org/oppia/app/player/audio/AudioUiManager.kt

@@ -4,6 +4,16 @@ import org.oppia.app.model.State
 
 /** Manager for updating audio state within the state player. */
 interface AudioUiManager {
+  /**
+   * Enables audio playback with the specified content ID as the initial content to play. Note that
+   * this corresponds to a response to the UI which means the action may fail with a dialog
+   * notifying the user why they can't enable audio playback right now.
+   */
+  fun enableAudioPlayback(contentId: String?)
+
+  /** Disables audio playback, stopping any currently playing tracks. */
+  fun disableAudioPlayback();
+
   /**
    * Used to set the state and explorationId for the audio player
    *

app/src/main/java/org/oppia/app/player/audio/AudioViewModel.kt

@@ -13,7 +13,7 @@ import org.oppia.domain.audio.AudioPlayerController
 import org.oppia.domain.audio.AudioPlayerController.PlayProgress
 import org.oppia.domain.audio.AudioPlayerController.PlayStatus
 import org.oppia.util.data.AsyncResult
-import org.oppia.util.gcsresource.DefaultResource
+import org.oppia.util.gcsresource.DefaultResourceBucketName
 import java.util.Locale
 import javax.inject.Inject
 
@@ -22,7 +22,7 @@ import javax.inject.Inject
 class AudioViewModel @Inject constructor(
   private val audioPlayerController: AudioPlayerController,
   private val fragment: Fragment,
-  @DefaultResource private val gcsResource: String
+  @DefaultResourceBucketName private val gcsResource: String
 ) : ViewModel() {
 
   private lateinit var state: State

app/src/main/java/org/oppia/app/player/exploration/ExplorationActivity.kt

@@ -13,15 +13,15 @@ import org.oppia.app.player.state.hintsandsolution.RevealHintListener
 import org.oppia.app.player.state.hintsandsolution.RevealSolutionInterface
 import org.oppia.app.player.state.listener.RouteToHintsAndSolutionListener
 import org.oppia.app.player.state.listener.StateKeyboardButtonListener
-import org.oppia.app.player.stopexploration.StopExplorationDialogFragment
-import org.oppia.app.player.stopexploration.StopExplorationInterface
+import org.oppia.app.player.stopplaying.StopExplorationDialogFragment
+import org.oppia.app.player.stopplaying.StopStatePlayingSessionListener
 import javax.inject.Inject
 
 private const val TAG_STOP_EXPLORATION_DIALOG = "STOP_EXPLORATION_DIALOG"
 const val TAG_HINTS_AND_SOLUTION_DIALOG = "HINTS_AND_SOLUTION_DIALOG"
 
 /** The starting point for exploration. */
-class ExplorationActivity : InjectableAppCompatActivity(), StopExplorationInterface, StateKeyboardButtonListener,
+class ExplorationActivity : InjectableAppCompatActivity(), StopStatePlayingSessionListener, StateKeyboardButtonListener,
   AudioButtonListener, HintsAndSolutionListener, RouteToHintsAndSolutionListener, RevealHintListener,
   RevealSolutionInterface {
 
@@ -83,7 +83,7 @@ class ExplorationActivity : InjectableAppCompatActivity(), StopExplorationInterf
     dialogFragment.showNow(supportFragmentManager, TAG_STOP_EXPLORATION_DIALOG)
   }
 
-  override fun stopExploration() {
+  override fun stopSession() {
     explorationActivityPresenter.stopExploration()
   }
 

app/src/main/java/org/oppia/app/player/exploration/ExplorationActivityPresenter.kt

@@ -116,6 +116,15 @@ class ExplorationActivityPresenter @Inject constructor(
     })
   }
 
+  fun onKeyboardAction(actionCode: Int) {
+    if (actionCode == EditorInfo.IME_ACTION_DONE) {
+      val explorationFragment = activity.supportFragmentManager.findFragmentByTag(
+        TAG_EXPLORATION_FRAGMENT
+      ) as? ExplorationFragment
+      explorationFragment?.onKeyboardAction()
+    }
+  }
+
   private fun updateToolbarTitle(explorationId: String) {
     subscribeToExploration(explorationDataController.getExplorationById(explorationId))
   }
@@ -152,14 +161,6 @@ class ExplorationActivityPresenter @Inject constructor(
     }
   }
 
-  fun onKeyboardAction(actionCode: Int) {
-    if (actionCode == EditorInfo.IME_ACTION_DONE) {
-      val explorationFragment =
-        activity.supportFragmentManager.findFragmentByTag(TAG_EXPLORATION_FRAGMENT) as ExplorationFragment
-      explorationFragment.onKeyboardAction()
-    }
-  }
-
   fun revealHint(saveUserChoice: Boolean, hintIndex: Int) {
     val explorationFragment =
       activity.supportFragmentManager.findFragmentByTag(TAG_EXPLORATION_FRAGMENT) as ExplorationFragment

app/src/main/java/org/oppia/app/player/exploration/ExplorationFragmentPresenter.kt

@@ -42,10 +42,6 @@ class ExplorationFragmentPresenter @Inject constructor(
 
   fun scrollToTop() = getStateFragment()?.scrollToTop()
 
-  private fun getStateFragment(): StateFragment? {
-    return fragment.childFragmentManager.findFragmentById(R.id.state_fragment_placeholder) as StateFragment?
-  }
-
   fun onKeyboardAction() {
     getStateFragment()?.handleKeyboardAction()
   }
@@ -57,4 +53,8 @@ class ExplorationFragmentPresenter @Inject constructor(
   fun revealSolution(saveUserChoice: Boolean){
     getStateFragment()?.revealSolution(saveUserChoice)
   }
+
+  private fun getStateFragment(): StateFragment? {
+    return fragment.childFragmentManager.findFragmentById(R.id.state_fragment_placeholder) as StateFragment?
+  }
 }

app/src/main/java/org/oppia/app/player/state/SelectionInteractionView.kt

@@ -12,6 +12,7 @@ import org.oppia.app.databinding.MultipleChoiceInteractionItemsBinding
 import org.oppia.app.fragment.InjectableFragment
 import org.oppia.app.player.state.itemviewmodel.SelectionInteractionContentViewModel
 import org.oppia.app.recyclerview.BindableAdapter
+import org.oppia.util.gcsresource.DefaultResourceBucketName
 import org.oppia.util.parser.ExplorationHtmlParserEntityType
 import org.oppia.util.parser.HtmlParser
 import javax.inject.Inject
@@ -37,7 +38,11 @@ class SelectionInteractionView @JvmOverloads constructor(
   @Inject
   @field:ExplorationHtmlParserEntityType
   lateinit var entityType: String
-  private lateinit var explorationId: String
+  @Inject
+  @field:DefaultResourceBucketName
+  lateinit var resourceBucketName: String
+
+  private lateinit var entityId: String
 
   override fun onAttachedToWindow() {
     super.onAttachedToWindow()
@@ -55,8 +60,8 @@ class SelectionInteractionView @JvmOverloads constructor(
 
   // TODO(#264): Clean up HTML parser such that it can be handled completely through a binding adapter, allowing
   //  TextViews that require custom Oppia HTML parsing to be fully automatically bound through data-binding.
-  fun setExplorationId(explorationId: String) {
-    this.explorationId = explorationId
+  fun setEntityId(entityId: String) {
+    this.entityId = entityId
   }
 
   private fun createAdapter(): BindableAdapter<SelectionInteractionContentViewModel> {
@@ -72,7 +77,9 @@ class SelectionInteractionView @JvmOverloads constructor(
           bindView = { view, viewModel ->
             val binding = DataBindingUtil.findBinding<ItemSelectionInteractionItemsBinding>(view)!!
             binding.htmlContent =
-              htmlParserFactory.create(entityType, explorationId, /* imageCenterAlign= */ false).parseOppiaHtml(
+              htmlParserFactory.create(
+                resourceBucketName, entityType, entityId, /* imageCenterAlign= */ false
+              ).parseOppiaHtml(
                 viewModel.htmlContent, binding.itemSelectionContentsTextView
               )
             binding.viewModel = viewModel
@@ -90,7 +97,9 @@ class SelectionInteractionView @JvmOverloads constructor(
           bindView = { view, viewModel ->
             val binding = DataBindingUtil.findBinding<MultipleChoiceInteractionItemsBinding>(view)!!
             binding.htmlContent =
-              htmlParserFactory.create(entityType, explorationId, /* imageCenterAlign= */ false).parseOppiaHtml(
+              htmlParserFactory.create(
+                resourceBucketName, entityType, entityId, /* imageCenterAlign= */ false
+              ).parseOppiaHtml(
                 viewModel.htmlContent, binding.multipleChoiceContentTextView
               )
             binding.viewModel = viewModel
@@ -108,7 +117,7 @@ fun setAllOptionsItemInputType(
 ) = selectionInteractionView.setAllOptionsItemInputType(selectionItemInputType)
 
 /** Sets the exploration ID for a specific [SelectionInteractionView] via data-binding. */
-@BindingAdapter("explorationId")
-fun setExplorationId(
-  selectionInteractionView: SelectionInteractionView, explorationId: String
-) = selectionInteractionView.setExplorationId(explorationId)
+@BindingAdapter("entityId")
+fun setEntityId(
+  selectionInteractionView: SelectionInteractionView, entityId: String
+) = selectionInteractionView.setEntityId(entityId)

app/src/main/java/org/oppia/app/player/state/StateFragment.kt

@@ -6,21 +6,25 @@ import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
 import org.oppia.app.fragment.InjectableFragment
+import org.oppia.app.model.HelpIndex
 import org.oppia.app.model.UserAnswer
 import org.oppia.app.player.state.answerhandling.InteractionAnswerErrorReceiver
 import org.oppia.app.player.state.answerhandling.InteractionAnswerHandler
 import org.oppia.app.player.state.answerhandling.InteractionAnswerReceiver
 import org.oppia.app.player.state.listener.ContinueNavigationButtonListener
 import org.oppia.app.player.state.listener.NextNavigationButtonListener
 import org.oppia.app.player.state.listener.PreviousNavigationButtonListener
+import org.oppia.app.player.state.listener.PreviousResponsesHeaderClickListener
 import org.oppia.app.player.state.listener.ReturnToTopicNavigationButtonListener
+import org.oppia.app.player.state.listener.ShowHintAvailabilityListener
 import org.oppia.app.player.state.listener.SubmitNavigationButtonListener
 import javax.inject.Inject
 
 /** Fragment that represents the current state of an exploration. */
 class StateFragment : InjectableFragment(), InteractionAnswerReceiver, InteractionAnswerHandler,
   InteractionAnswerErrorReceiver, ContinueNavigationButtonListener, NextNavigationButtonListener,
-  PreviousNavigationButtonListener, ReturnToTopicNavigationButtonListener, SubmitNavigationButtonListener {
+  PreviousNavigationButtonListener, ReturnToTopicNavigationButtonListener, SubmitNavigationButtonListener,
+  PreviousResponsesHeaderClickListener, ShowHintAvailabilityListener {
   companion object {
     /**
      * Creates a new instance of a StateFragment.
@@ -78,6 +82,10 @@ class StateFragment : InjectableFragment(), InteractionAnswerReceiver, Interacti
 
   override fun onSubmitButtonClicked() = stateFragmentPresenter.onSubmitButtonClicked()
 
+  override fun onResponsesHeaderClicked() = stateFragmentPresenter.onResponsesHeaderClicked()
+
+  override fun onHintAvailable(helpIndex: HelpIndex) = stateFragmentPresenter.onHintAvailable(helpIndex)
+
   fun handlePlayAudio() = stateFragmentPresenter.handleAudioClick()
 
   fun handleKeyboardAction() = stateFragmentPresenter.handleKeyboardAction()