Fix #117: Introduce topic list controller interface [Blocked: #175] (#…

…176)

* Introduce initially viable TopicListController interface with tests, and
no real implementation.

This commit includes thumbnail structures that should be split into its
own branch/PR since other controllers will depend on it.

* Introduce 6 sample thumbnail graphics locally and a proto data structure
for thumbnails that can be used for lessons.

* Update topic list controller to use new-and-improved thumbnail options.

* Fix post-merge breakages.

* Address review comment.

domain/src/main/java/org/oppia/domain/topic/TopicListController.kt

@@ -0,0 +1,117 @@
+package org.oppia.domain.topic
+
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.MutableLiveData
+import java.util.concurrent.TimeUnit
+import javax.inject.Inject
+import javax.inject.Singleton
+import org.oppia.app.model.LessonThumbnail
+import org.oppia.app.model.LessonThumbnailGraphic
+import org.oppia.app.model.OngoingStoryList
+import org.oppia.app.model.PromotedStory
+import org.oppia.app.model.TopicList
+import org.oppia.app.model.TopicSummary
+import org.oppia.util.data.AsyncResult
+
+const val TEST_TOPIC_ID_0 = "test_topic_id_0"
+const val TEST_TOPIC_ID_1 = "test_topic_id_1"
+
+private val EVICTION_TIME_MILLIS = TimeUnit.DAYS.toMillis(1)
+
+/** Controller for retrieving the list of topics available to the learner to play. */
+@Singleton
+class TopicListController @Inject constructor() {
+  /**
+   * Returns the list of [TopicSummary]s currently tracked by the app, possibly up to
+   * [EVICTION_TIME_MILLIS] old.
+   */
+  fun getTopicList(): LiveData<AsyncResult<TopicList>> {
+    return MutableLiveData(AsyncResult.success(createTopicList()))
+  }
+
+  /**
+   * Returns the list of ongoing [PromotedStory]s that can be viewed via a link on the homescreen. The total number of
+   * promoted stories should correspond to the ongoing story count within the [TopicList] returned by [getTopicList].
+   */
+  fun getOngoingStoryList(): LiveData<AsyncResult<OngoingStoryList>> {
+    return MutableLiveData(AsyncResult.success(createOngoingStoryList()))
+  }
+
+  private fun createTopicList(): TopicList {
+    return TopicList.newBuilder()
+      .setPromotedStory(createPromotedStory1())
+      .addTopicSummary(createTopicSummary0())
+      .addTopicSummary(createTopicSummary1())
+      .setOngoingStoryCount(2)
+      .build()
+  }
+
+  private fun createTopicSummary0(): TopicSummary {
+    return TopicSummary.newBuilder()
+      .setTopicId(TEST_TOPIC_ID_0)
+      .setName("First Topic")
+      .setVersion(1)
+      .setSubtopicCount(0)
+      .setCanonicalStoryCount(2)
+      .setUncategorizedSkillCount(0)
+      .setAdditionalStoryCount(0)
+      .setTotalSkillCount(2)
+      .setTotalChapterCount(4)
+      .setTopicThumbnail(createTopicThumbnail0())
+      .build()
+  }
+
+  private fun createTopicSummary1(): TopicSummary {
+    return TopicSummary.newBuilder()
+      .setTopicId(TEST_TOPIC_ID_1)
+      .setName("Second Topic")
+      .setVersion(3)
+      .setSubtopicCount(0)
+      .setCanonicalStoryCount(1)
+      .setUncategorizedSkillCount(0)
+      .setAdditionalStoryCount(0)
+      .setTotalSkillCount(1)
+      .setTotalChapterCount(1)
+      .setTopicThumbnail(createTopicThumbnail1())
+      .build()
+  }
+
+  private fun createOngoingStoryList(): OngoingStoryList {
+    return OngoingStoryList.newBuilder()
+      .addRecentStory(createPromotedStory1())
+      .build()
+  }
+
+  private fun createPromotedStory1(): PromotedStory {
+    return PromotedStory.newBuilder()
+      .setStoryId(TEST_STORY_ID_1)
+      .setStoryName("Second Story")
+      .setTopicId(TEST_TOPIC_ID_0)
+      .setTopicName("First Topic")
+      .setCompletedChapterCount(1)
+      .setTotalChapterCount(3)
+      .setLessonThumbnail(createStoryThumbnail())
+      .build()
+  }
+
+  private fun createTopicThumbnail0(): LessonThumbnail {
+    return LessonThumbnail.newBuilder()
+      .setThumbnailGraphic(LessonThumbnailGraphic.CHILD_WITH_BOOK)
+      .setBackgroundColorRgb(0xd5836f)
+      .build()
+  }
+
+  private fun createTopicThumbnail1(): LessonThumbnail {
+    return LessonThumbnail.newBuilder()
+      .setThumbnailGraphic(LessonThumbnailGraphic.CHILD_WITH_CUPCAKES)
+      .setBackgroundColorRgb(0xf7bf73)
+      .build()
+  }
+
+  private fun createStoryThumbnail(): LessonThumbnail {
+    return LessonThumbnail.newBuilder()
+      .setThumbnailGraphic(LessonThumbnailGraphic.DUCK_AND_CHICKEN)
+      .setBackgroundColorRgb(0xa5d3ec)
+      .build()
+  }
+}

domain/src/test/java/org/oppia/domain/topic/TopicListControllerTest.kt

@@ -0,0 +1,242 @@
+package org.oppia.domain.topic
+
+import android.app.Application
+import android.content.Context
+import androidx.test.core.app.ApplicationProvider
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import com.google.common.truth.Truth.assertThat
+import dagger.BindsInstance
+import dagger.Component
+import dagger.Module
+import dagger.Provides
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.oppia.app.model.LessonThumbnailGraphic
+import org.robolectric.annotation.Config
+import javax.inject.Inject
+import javax.inject.Singleton
+
+/** Tests for [TopicListController]. */
+@RunWith(AndroidJUnit4::class)
+@Config(manifest = Config.NONE)
+class TopicListControllerTest {
+  @Inject
+  lateinit var topicListController: TopicListController
+
+  @Before
+  fun setUp() {
+    setUpTestApplicationComponent()
+  }
+
+  // TODO(#15): Add tests for recommended lessons rather than promoted, and tests for the 'continue playing' LiveData
+  //  not providing any data for cases when there are no ongoing lessons. Also, add tests for other uncovered cases
+  //  (such as having and not having lessons in either of the OngoingStoryList section, or AsyncResult errors).
+
+  @Test
+  fun testRetrieveTopicList_isSuccessful() {
+    val topicListLiveData = topicListController.getTopicList()
+
+    val topicListResult = topicListLiveData.value
+    assertThat(topicListResult).isNotNull()
+    assertThat(topicListResult!!.isSuccess()).isTrue()
+  }
+
+  @Test
+  fun testRetrieveTopicList_providesListOfMultipleTopics() {
+    val topicListLiveData = topicListController.getTopicList()
+
+    val topicList = topicListLiveData.value!!.getOrThrow()
+    assertThat(topicList.topicSummaryCount).isGreaterThan(1)
+  }
+
+  @Test
+  fun testRetrieveTopicList_firstTopic_hasCorrectTopicInfo() {
+    val topicListLiveData = topicListController.getTopicList()
+
+    val topicList = topicListLiveData.value!!.getOrThrow()
+    val firstTopic = topicList.getTopicSummary(0)
+    assertThat(firstTopic.topicId).isEqualTo(TEST_TOPIC_ID_0)
+    assertThat(firstTopic.name).isEqualTo("First Topic")
+  }
+
+  @Test
+  fun testRetrieveTopicList_firstTopic_hasCorrectThumbnail() {
+    val topicListLiveData = topicListController.getTopicList()
+
+    val topicList = topicListLiveData.value!!.getOrThrow()
+    val firstTopic = topicList.getTopicSummary(0)
+    assertThat(firstTopic.topicThumbnail.thumbnailGraphic).isEqualTo(LessonThumbnailGraphic.CHILD_WITH_BOOK)
+  }
+
+  @Test
+  fun testRetrieveTopicList_firstTopic_hasCorrectLessonCount() {
+    val topicListLiveData = topicListController.getTopicList()
+
+    val topicList = topicListLiveData.value!!.getOrThrow()
+    val firstTopic = topicList.getTopicSummary(0)
+    assertThat(firstTopic.totalChapterCount).isEqualTo(4)
+  }
+
+  @Test
+  fun testRetrieveTopicList_secondTopic_hasCorrectTopicInfo() {
+    val topicListLiveData = topicListController.getTopicList()
+
+    val topicList = topicListLiveData.value!!.getOrThrow()
+    val secondTopic = topicList.getTopicSummary(1)
+    assertThat(secondTopic.topicId).isEqualTo(TEST_TOPIC_ID_1)
+    assertThat(secondTopic.name).isEqualTo("Second Topic")
+  }
+
+  @Test
+  fun testRetrieveTopicList_secondTopic_hasCorrectThumbnail() {
+    val topicListLiveData = topicListController.getTopicList()
+
+    val topicList = topicListLiveData.value!!.getOrThrow()
+    val secondTopic = topicList.getTopicSummary(1)
+    assertThat(secondTopic.topicThumbnail.thumbnailGraphic).isEqualTo(LessonThumbnailGraphic.CHILD_WITH_CUPCAKES)
+  }
+
+  @Test
+  fun testRetrieveTopicList_secondTopic_hasCorrectLessonCount() {
+    val topicListLiveData = topicListController.getTopicList()
+
+    val topicList = topicListLiveData.value!!.getOrThrow()
+    val secondTopic = topicList.getTopicSummary(1)
+    assertThat(secondTopic.totalChapterCount).isEqualTo(1)
+  }
+
+  @Test
+  fun testRetrieveTopicList_promotedLesson_hasCorrectLessonInfo() {
+    val topicListLiveData = topicListController.getTopicList()
+
+    val topicList = topicListLiveData.value!!.getOrThrow()
+    val promotedStory = topicList.promotedStory
+    assertThat(promotedStory.storyId).isEqualTo(TEST_STORY_ID_1)
+    assertThat(promotedStory.storyName).isEqualTo("Second Story")
+  }
+
+  @Test
+  fun testRetrieveTopicList_promotedLesson_hasCorrectTopicInfo() {
+    val topicListLiveData = topicListController.getTopicList()
+
+    val topicList = topicListLiveData.value!!.getOrThrow()
+    val promotedStory = topicList.promotedStory
+    assertThat(promotedStory.topicId).isEqualTo(TEST_TOPIC_ID_0)
+    assertThat(promotedStory.topicName).isEqualTo("First Topic")
+  }
+
+  @Test
+  fun testRetrieveTopicList_promotedLesson_hasCorrectCompletionStats() {
+    val topicListLiveData = topicListController.getTopicList()
+
+    val topicList = topicListLiveData.value!!.getOrThrow()
+    val promotedStory = topicList.promotedStory
+    assertThat(promotedStory.completedChapterCount).isEqualTo(1)
+    assertThat(promotedStory.totalChapterCount).isEqualTo(3)
+  }
+
+  @Test
+  fun testRetrieveTopicList_hasMultipleOngoingLessons() {
+    val topicListLiveData = topicListController.getTopicList()
+
+    val topicList = topicListLiveData.value!!.getOrThrow()
+    assertThat(topicList.ongoingStoryCount).isEqualTo(2)
+  }
+
+  @Test
+  fun testRetrieveOngoingStoryList_isSuccessful() {
+    val ongoingStoryListLiveData = topicListController.getOngoingStoryList()
+
+    val ongoingStoryListResult = ongoingStoryListLiveData.value
+    assertThat(ongoingStoryListResult).isNotNull()
+    assertThat(ongoingStoryListResult!!.isSuccess()).isTrue()
+  }
+
+  @Test
+  fun testRetrieveOngoingStoryList_withinSevenDays_hasOngoingLesson() {
+    val ongoingStoryListLiveData = topicListController.getOngoingStoryList()
+
+    val ongoingStoryList = ongoingStoryListLiveData.value!!.getOrThrow()
+    assertThat(ongoingStoryList.recentStoryCount).isEqualTo(1)
+  }
+
+  @Test
+  fun testRetrieveOngoingStoryList_recentLesson_hasCorrectStoryInfo() {
+    val ongoingStoryListLiveData = topicListController.getOngoingStoryList()
+
+    val ongoingStoryList = ongoingStoryListLiveData.value!!.getOrThrow()
+    val recentLesson = ongoingStoryList.getRecentStory(0)
+    assertThat(recentLesson.storyId).isEqualTo(TEST_STORY_ID_1)
+    assertThat(recentLesson.storyName).isEqualTo("Second Story")
+  }
+
+  @Test
+  fun testRetrieveOngoingStoryList_recentLesson_hasCorrectTopicInfo() {
+    val ongoingStoryListLiveData = topicListController.getOngoingStoryList()
+
+    val ongoingStoryList = ongoingStoryListLiveData.value!!.getOrThrow()
+    val recentLesson = ongoingStoryList.getRecentStory(0)
+    assertThat(recentLesson.topicId).isEqualTo(TEST_TOPIC_ID_0)
+    assertThat(recentLesson.topicName).isEqualTo("First Topic")
+  }
+
+  @Test
+  fun testRetrieveOngoingStoryList_recentLesson_hasCorrectCompletionStats() {
+    val ongoingStoryListLiveData = topicListController.getOngoingStoryList()
+
+    val ongoingStoryList = ongoingStoryListLiveData.value!!.getOrThrow()
+    val recentLesson = ongoingStoryList.getRecentStory(0)
+    assertThat(recentLesson.completedChapterCount).isEqualTo(1)
+    assertThat(recentLesson.totalChapterCount).isEqualTo(3)
+  }
+
+  @Test
+  fun testRetrieveOngoingStoryList_recentLesson_hasCorrectThumbnail() {
+    val ongoingStoryListLiveData = topicListController.getOngoingStoryList()
+
+    val ongoingStoryList = ongoingStoryListLiveData.value!!.getOrThrow()
+    val recentLesson = ongoingStoryList.getRecentStory(0)
+    assertThat(recentLesson.lessonThumbnail.thumbnailGraphic).isEqualTo(LessonThumbnailGraphic.DUCK_AND_CHICKEN)
+  }
+
+  @Test
+  fun testRetrieveOngoingStoryList_earlierThanSevenDays_doesNotHaveOngoingLesson() {
+    val ongoingStoryListLiveData = topicListController.getOngoingStoryList()
+
+    val ongoingStoryList = ongoingStoryListLiveData.value!!.getOrThrow()
+    assertThat(ongoingStoryList.olderStoryCount).isEqualTo(0)
+  }
+
+  private fun setUpTestApplicationComponent() {
+    DaggerTopicListControllerTest_TestApplicationComponent.builder()
+      .setApplication(ApplicationProvider.getApplicationContext())
+      .build()
+      .inject(this)
+  }
+
+  // TODO(#89): Move this to a common test application component.
+  @Module
+  class TestModule {
+    @Provides
+    @Singleton
+    fun provideContext(application: Application): Context {
+      return application
+    }
+  }
+
+  // TODO(#89): Move this to a common test application component.
+  @Singleton
+  @Component(modules = [TestModule::class])
+  interface TestApplicationComponent {
+    @Component.Builder
+    interface Builder {
+      @BindsInstance
+      fun setApplication(application: Application): Builder
+
+      fun build(): TestApplicationComponent
+    }
+
+    fun inject(topicListControllerTest: TopicListControllerTest)
+  }
+}