Fix part of #2132: Chapter List Page Issues

app/src/main/java/org/oppia/android/app/story/storyitemviewmodel/StoryChapterSummaryViewModel.kt

@@ -28,6 +28,7 @@ class StoryChapterSummaryViewModel(
   val name: String = chapterSummary.name
   val summary: String = chapterSummary.summary
   val chapterThumbnail: LessonThumbnail = chapterSummary.chapterThumbnail
+  val missingPrerequisiteChapter: ChapterSummary = chapterSummary.missingPrerequisiteChapter
 
   fun onExplorationClicked() {
     explorationDataController.stopPlayingExploration()

app/src/main/res/layout-land/story_chapter_view.xml

@@ -76,10 +76,8 @@
             android:layout_marginTop="8dp"
             android:layout_marginEnd="8dp"
             android:layout_marginBottom="4dp"
-            android:ellipsize="end"
             android:fontFamily="sans-serif"
-            android:maxLines="3"
-            android:text="@{htmlContent}"
+            android:text="@{viewModel.chapterSummary.chapterPlayState != ChapterPlayState.NOT_PLAYABLE_MISSING_PREREQUISITES ? htmlContent : @string/chapter_prerequisite_title_label(viewModel.index, viewModel.missingPrerequisiteChapter.name)}"
             android:textColor="@color/oppiaPrimaryText"
             android:textSize="16sp"
             app:layout_constraintBottom_toBottomOf="parent"

app/src/main/res/layout-sw600dp/story_chapter_view.xml

@@ -89,10 +89,8 @@
             android:layout_marginTop="8dp"
             android:layout_marginEnd="8dp"
             android:layout_marginBottom="4dp"
-            android:ellipsize="end"
             android:fontFamily="sans-serif"
-            android:maxLines="4"
-            android:text="@{htmlContent}"
+            android:text="@{viewModel.chapterSummary.chapterPlayState != ChapterPlayState.NOT_PLAYABLE_MISSING_PREREQUISITES ? htmlContent : @string/chapter_prerequisite_title_label(viewModel.index, viewModel.missingPrerequisiteChapter.name)}"
             android:textColor="@color/oppiaPrimaryText"
             android:textSize="16sp"
             app:layout_constraintBottom_toBottomOf="parent"

app/src/main/res/layout/story_chapter_view.xml

@@ -89,10 +89,8 @@
             android:layout_marginTop="8dp"
             android:layout_marginEnd="8dp"
             android:layout_marginBottom="4dp"
-            android:ellipsize="end"
             android:fontFamily="sans-serif"
-            android:maxLines="4"
-            android:text="@{htmlContent}"
+            android:text="@{viewModel.chapterSummary.chapterPlayState != ChapterPlayState.NOT_PLAYABLE_MISSING_PREREQUISITES ? htmlContent : @string/chapter_prerequisite_title_label(viewModel.index, viewModel.missingPrerequisiteChapter.name)}"
             android:textColor="@color/oppiaPrimaryText"
             android:textSize="16sp"
             app:layout_constraintBottom_toBottomOf="parent"

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

@@ -299,7 +299,7 @@
 
   <dimen name="story_chapter_card_playable_state_elevation">4dp</dimen>
   <dimen name="ongoing_topic_card_elevation">4dp</dimen>
-  <dimen name="story_chapter_card_not_playable_state_elevation">0dp</dimen>
+  <dimen name="story_chapter_card_not_playable_state_elevation">2dp</dimen>
   <dimen name="profile_chooser_padding_bottom_profile_already_added">224dp</dimen>
 
   <dimen name="continue_item_exploration_split_view_margin_top">72dp</dimen>

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

@@ -63,6 +63,7 @@
   <string name="topic_play_chapter_index">%s.</string>
   <string name="chapter_name">Chapter %s: %s</string>
   <string name="chapter_completed">Chapter %s: %s is completed.</string>
+  <string name="chapter_prerequisite_title_label">Complete Chapter %s: %s to unlock this chapter.</string>
   <string name="text_input_default_content_description">Enter text.</string>
   <string name="fractions_default_hint_text">Enter a fraction in the form x/x, or a mixed number in the form x x/x.</string>
   <string name="fractions_default_hint_text_no_integer">Enter a fraction in the form x/x.</string>

app/src/sharedTest/java/org/oppia/android/app/story/StoryFragmentTest.kt

@@ -117,10 +117,6 @@ class StoryFragmentTest {
     profileTestHelper.initializeProfiles()
     FirebaseApp.initializeApp(context)
     profileId = ProfileId.newBuilder().setInternalId(internalProfileId).build()
-    storyProgressTestHelper.markPartialStoryProgressForFractions(
-      profileId,
-      timestampOlderThanAWeek = false
-    )
     testCoroutineDispatchers.runCurrent()
   }
 
@@ -159,6 +155,10 @@ class StoryFragmentTest {
   @Test
   fun testStoryFragment_correctStoryCountLoadedInHeader() {
     launch<StoryActivity>(createStoryActivityIntent()).use {
+      storyProgressTestHelper.markPartialStoryProgressForFractions(
+        profileId,
+        timestampOlderThanAWeek = false
+      )
       testCoroutineDispatchers.runCurrent()
       val headerString: String =
         getResources().getQuantityString(R.plurals.story_total_chapters, 2, 1, 2)
@@ -242,6 +242,41 @@ class StoryFragmentTest {
     }
   }
 
+  @Test
+  fun testStoryFragment_chapterMissingPrerequisiteIsShownCorrectly() {
+    launch<StoryActivity>(createStoryActivityIntent()).use {
+      testCoroutineDispatchers.runCurrent()
+      onView(allOf(withId(R.id.story_chapter_list))).perform(
+        scrollToPosition<RecyclerView.ViewHolder>(
+          2
+        )
+      )
+      onView(atPositionOnView(R.id.story_chapter_list, 2, R.id.chapter_summary)).check(
+        matches(
+          withText("Complete Chapter 1: What is a Fraction? to unlock this chapter.")
+        )
+      )
+    }
+  }
+
+  @Test
+  fun testStoryFragment_changeConfiguration_chapterMissingPrerequisiteIsShownCorrectly() {
+    launch<StoryActivity>(createStoryActivityIntent()).use {
+      testCoroutineDispatchers.runCurrent()
+      onView(isRoot()).perform(orientationLandscape())
+      onView(allOf(withId(R.id.story_chapter_list))).perform(
+        scrollToPosition<RecyclerView.ViewHolder>(
+          2
+        )
+      )
+      onView(atPositionOnView(R.id.story_chapter_list, 2, R.id.chapter_summary)).check(
+        matches(
+          withText("Complete Chapter 1: What is a Fraction? to unlock this chapter.")
+        )
+      )
+    }
+  }
+
   @Test
   fun testStoryFragment_changeConfiguration_explorationStartCorrectly() {
     launch<StoryActivity>(createStoryActivityIntent()).use {
@@ -263,6 +298,10 @@ class StoryFragmentTest {
   @Test
   fun testStoryFragment_changeConfiguration_correctStoryCountInHeader() {
     launch<StoryActivity>(createStoryActivityIntent()).use {
+      storyProgressTestHelper.markPartialStoryProgressForFractions(
+        profileId,
+        timestampOlderThanAWeek = false
+      )
       testCoroutineDispatchers.runCurrent()
       onView(isRoot()).perform(orientationLandscape())
       val headerString: String =

domain/src/main/java/org/oppia/android/domain/topic/TopicController.kt

@@ -333,24 +333,20 @@ class TopicController @Inject constructor(
     if (storyProgress.chapterProgressMap.isNotEmpty()) {
       val storyBuilder = storySummary.toBuilder()
       storySummary.chapterList.forEachIndexed { chapterIndex, chapterSummary ->
+        val chapterBuilder = chapterSummary.toBuilder()
         if (storyProgress.chapterProgressMap.containsKey(chapterSummary.explorationId)) {
-          val chapterBuilder = chapterSummary.toBuilder()
           chapterBuilder.chapterPlayState =
             storyProgress.chapterProgressMap[chapterSummary.explorationId]!!.chapterPlayState
-          storyBuilder.setChapter(chapterIndex, chapterBuilder)
         } else {
-          if (storyBuilder.getChapter(chapterIndex - 1).chapterPlayState ==
-            ChapterPlayState.COMPLETED
-          ) {
-            val chapterBuilder = chapterSummary.toBuilder()
+          val prerequisiteChapter = storyBuilder.getChapter(chapterIndex - 1)
+          if (prerequisiteChapter.chapterPlayState == ChapterPlayState.COMPLETED) {
             chapterBuilder.chapterPlayState = ChapterPlayState.NOT_STARTED
-            storyBuilder.setChapter(chapterIndex, chapterBuilder)
           } else {
-            val chapterBuilder = chapterSummary.toBuilder()
             chapterBuilder.chapterPlayState = ChapterPlayState.NOT_PLAYABLE_MISSING_PREREQUISITES
-            storyBuilder.setChapter(chapterIndex, chapterBuilder)
+            chapterBuilder.missingPrerequisiteChapter = prerequisiteChapter
           }
         }
+        storyBuilder.setChapter(chapterIndex, chapterBuilder)
       }
       return storyBuilder.build()
     } else {
@@ -386,10 +382,11 @@ class TopicController @Inject constructor(
       val storyBuilder = storySummary.toBuilder()
       storySummary.chapterList.forEachIndexed { index, chapterSummary ->
         val chapterBuilder = chapterSummary.toBuilder()
-        chapterBuilder.chapterPlayState = if (index != 0) {
-          ChapterPlayState.NOT_PLAYABLE_MISSING_PREREQUISITES
+        if (index != 0) {
+          chapterBuilder.chapterPlayState = ChapterPlayState.NOT_PLAYABLE_MISSING_PREREQUISITES
+          chapterBuilder.missingPrerequisiteChapter = storySummary.chapterList.get(index - 1)
         } else {
-          ChapterPlayState.NOT_STARTED
+          chapterBuilder.chapterPlayState = ChapterPlayState.NOT_STARTED
         }
         storyBuilder.setChapter(index, chapterBuilder)
       }

domain/src/test/java/org/oppia/android/domain/topic/TopicControllerTest.kt

@@ -413,7 +413,7 @@ class TopicControllerTest {
   }
 
   @Test
-  fun testRetrieveStory_validSecondStory_returnsStoryWithProgress() {
+  fun testRetrieveStory_validSecondStory_returnsStoryWithoutProgress() {
     topicController.getStory(profileId1, TEST_TOPIC_ID_0, TEST_STORY_ID_1).toLiveData()
       .observeForever(mockStorySummaryObserver)
     testCoroutineDispatchers.runCurrent()
@@ -424,8 +424,31 @@ class TopicControllerTest {
       .isEqualTo(ChapterPlayState.NOT_STARTED)
     assertThat(story.getChapter(1).chapterPlayState)
       .isEqualTo(ChapterPlayState.NOT_PLAYABLE_MISSING_PREREQUISITES)
+    assertThat(story.getChapter(1).missingPrerequisiteChapter.name)
+      .isEqualTo(story.getChapter(0).name)
+    assertThat(story.getChapter(2).chapterPlayState)
+      .isEqualTo(ChapterPlayState.NOT_PLAYABLE_MISSING_PREREQUISITES)
+    assertThat(story.getChapter(2).missingPrerequisiteChapter.name)
+      .isEqualTo(story.getChapter(1).name)
+  }
+
+  @Test
+  fun testRetrieveStory_validSecondStory_returnsStoryWithProgress() {
+    topicController.getStory(profileId1, TEST_TOPIC_ID_0, TEST_STORY_ID_1).toLiveData()
+      .observeForever(mockStorySummaryObserver)
+    markSecondStory1Chapter1AsCompleted()
+    testCoroutineDispatchers.runCurrent()
+
+    verifyGetStorySucceeded()
+    val story = storySummaryResultCaptor.value!!.getOrThrow()
+    assertThat(story.getChapter(0).chapterPlayState)
+      .isEqualTo(ChapterPlayState.COMPLETED)
+    assertThat(story.getChapter(1).chapterPlayState)
+      .isEqualTo(ChapterPlayState.NOT_STARTED)
     assertThat(story.getChapter(2).chapterPlayState)
       .isEqualTo(ChapterPlayState.NOT_PLAYABLE_MISSING_PREREQUISITES)
+    assertThat(story.getChapter(2).missingPrerequisiteChapter.name)
+      .isEqualTo(story.getChapter(1).name)
   }
 
   @Test
@@ -884,6 +907,8 @@ class TopicControllerTest {
       .isEqualTo(ChapterPlayState.NOT_STARTED)
     assertThat(topic.storyList[0].chapterList[1].chapterPlayState)
       .isEqualTo(ChapterPlayState.NOT_PLAYABLE_MISSING_PREREQUISITES)
+    assertThat(topic.storyList[0].chapterList[1].missingPrerequisiteChapter.name)
+      .isEqualTo(topic.storyList[0].chapterList[0].name)
   }
 
   @Test
@@ -927,6 +952,8 @@ class TopicControllerTest {
       .isEqualTo(ChapterPlayState.NOT_STARTED)
     assertThat(storySummary.chapterList[1].chapterPlayState)
       .isEqualTo(ChapterPlayState.NOT_PLAYABLE_MISSING_PREREQUISITES)
+    assertThat(storySummary.chapterList[1].missingPrerequisiteChapter.name)
+      .isEqualTo(storySummary.chapterList[0].name)
   }
 
   @Test
@@ -1162,6 +1189,16 @@ class TopicControllerTest {
     ).toLiveData().observeForever(mockRecordProgressObserver)
   }
 
+  private fun markSecondStory1Chapter1AsCompleted() {
+    storyProgressController.recordCompletedChapter(
+      profileId1,
+      TEST_TOPIC_ID_0,
+      TEST_STORY_ID_1,
+      TEST_EXPLORATION_ID_1,
+      currentTimestamp
+    ).toLiveData().observeForever(mockRecordProgressObserver)
+  }
+
   private fun markRatiosStory0Chapter0AsCompleted() {
     storyProgressController.recordCompletedChapter(
       profileId1,

model/src/main/proto/topic.proto

@@ -88,6 +88,10 @@ message ChapterSummary {
 
   // The thumbnail corresponding to this chapter.
   LessonThumbnail chapter_thumbnail = 5;
+
+  // Prerequisite chapter to unlock this chapter. It is only defined when the play state of this
+  // chapter is NOT_PLAYABLE_MISSING_PREREQUISITES.
+  ChapterSummary missing_prerequisite_chapter = 6;
 }
 
 // A summary of a skill that can be trained or reviewed by the player.