oppia · BenHenning · Apr 23, 2021 · Mar 23, 2021 · Mar 23, 2021 · Mar 23, 2021
@@ -664,7 +664,6 @@ kt_android_library(
         "src/sharedTest/java/org/oppia/android/app/utility/DrawableMatcher.kt",
         "src/sharedTest/java/org/oppia/android/app/utility/EspressoTestsMatchers.kt",
         "src/sharedTest/java/org/oppia/android/app/utility/FontSizeMatcher.kt",
-        "src/sharedTest/java/org/oppia/android/app/utility/MockitoKotlinHelper.kt",
         "src/sharedTest/java/org/oppia/android/app/utility/OrientationChangeAction.kt",
         "src/sharedTest/java/org/oppia/android/app/utility/ProgressMatcher.kt",
         "src/sharedTest/java/org/oppia/android/app/utility/TabMatcher.kt",
@@ -684,6 +683,7 @@ TEST_DEPS = [
     ":test_deps",
     "//domain",
     "//testing",
+    "//testing/src/main/java/org/oppia/android/testing/mockito",
     "//testing/src/main/java/org/oppia/android/testing/robolectric:is_on_robolectric",
     "//testing/src/main/java/org/oppia/android/testing/robolectric:test_module",
     "//testing/src/main/java/org/oppia/android/testing/threading:coroutine_executor_service",

@@ -66,8 +66,6 @@ import org.oppia.android.app.recyclerview.RecyclerViewMatcher.Companion.atPositi
 import org.oppia.android.app.recyclerview.RecyclerViewMatcher.Companion.hasItemCount
 import org.oppia.android.app.shim.ViewBindingShimModule
 import org.oppia.android.app.utility.OrientationChangeAction.Companion.orientationLandscape
-import org.oppia.android.app.utility.anyOrNull
-import org.oppia.android.app.utility.capture
 import org.oppia.android.domain.classify.InteractionsModule
 import org.oppia.android.domain.classify.rules.continueinteraction.ContinueModule
 import org.oppia.android.domain.classify.rules.dragAndDropSortInput.DragDropSortInputModule
@@ -90,6 +88,8 @@ import org.oppia.android.domain.topic.PrimeTopicAssetsControllerModule
 import org.oppia.android.domain.topic.TEST_STORY_ID_0
 import org.oppia.android.domain.topic.TEST_TOPIC_ID_0
 import org.oppia.android.testing.TestLogReportingModule
+import org.oppia.android.testing.mockito.anyOrNull
+import org.oppia.android.testing.mockito.capture
 import org.oppia.android.testing.profile.ProfileTestHelper
 import org.oppia.android.testing.robolectric.RobolectricModule
 import org.oppia.android.testing.story.StoryProgressTestHelper

@@ -42,7 +42,6 @@ import org.oppia.android.app.utility.DefaultRegionClickedEvent
 import org.oppia.android.app.utility.NamedRegionClickedEvent
 import org.oppia.android.app.utility.OnClickableAreaClickedListener
 import org.oppia.android.app.utility.RegionClickedEvent
-import org.oppia.android.app.utility.capture
 import org.oppia.android.app.utility.clickPoint
 import org.oppia.android.domain.classify.InteractionsModule
 import org.oppia.android.domain.classify.rules.continueinteraction.ContinueModule
@@ -62,6 +61,7 @@ import org.oppia.android.domain.oppialogger.loguploader.WorkManagerConfiguration
 import org.oppia.android.domain.question.QuestionModule
 import org.oppia.android.domain.topic.PrimeTopicAssetsControllerModule
 import org.oppia.android.testing.TestLogReportingModule
+import org.oppia.android.testing.mockito.capture
 import org.oppia.android.testing.robolectric.RobolectricModule
 import org.oppia.android.testing.threading.TestDispatcherModule
 import org.oppia.android.testing.time.FakeOppiaClockModule

@@ -12,6 +12,7 @@ load("//testing:testing_test.bzl", "testing_test")
 # globs here to ensure new files added to migrated packages don't accidentally get included in the
 # top-level module library.
 MIGRATED_PROD_FILES = glob([
+    "src/main/java/org/oppia/android/testing/mockito/*.kt",
     "src/main/java/org/oppia/android/testing/robolectric/*.kt",
     "src/main/java/org/oppia/android/testing/threading/*.kt",
     "src/main/java/org/oppia/android/testing/time/*.kt",

@@ -0,0 +1,19 @@
+# TODO(#1532): Rename file to 'BUILD' post-Gradle.
+"""
+Package for Mockito-specific test utilities and helpers.
+"""
+
+load("@io_bazel_rules_kotlin//kotlin:kotlin.bzl", "kt_android_library")
+
+# Library for general-purpose testing fakes.
+kt_android_library(
+    name = "mockito",
+    testonly = True,
+    srcs = [
+        "MockitoKotlinHelper.kt",
+    ],
+    visibility = ["//:oppia_testing_visibility"],
+    deps = [
+        "//third_party:org_mockito_mockito-core",
+    ],
+)
@@ -0,0 +1,17 @@
+package org.oppia.android.testing.mockito
+
+import org.mockito.ArgumentCaptor
+import org.mockito.Mockito.any
+
+/**
+ * Returns ArgumentCaptor.capture() as a non-nullable type to avoid either an IllegalStateException
+ * or a NullPointerException (essentially making Mockito's argument captor Kotlin-compatible).
+ *
+ * This hacky solution is necessary since Kotlin doesn't allow null values to be passed in for
+ * non-nullable parameters, yet this is fundamentally how Mockito works internally when tracking
+ * captors.
+ */
+fun <T> capture(argumentCaptor: ArgumentCaptor<T>): T = argumentCaptor.capture()
+
+/** Matches anything, including nulls. */
+fun <T> anyOrNull(): T = any()
@@ -74,6 +74,7 @@ TEST_DEPS = [
     "//model",
     "//model:test_models",
     "//testing",
+    "//testing/src/main/java/org/oppia/android/testing/mockito",
     "//testing/src/main/java/org/oppia/android/testing/robolectric:test_module",
     "//testing/src/main/java/org/oppia/android/testing/threading:test_module",
     "//testing/src/main/java/org/oppia/android/testing/time:test_module",

diff --git a/utility/src/main/java/org/oppia/android/util/parser/ConceptCardTagHandler.kt b/utility/src/main/java/org/oppia/android/util/parser/ConceptCardTagHandler.kt
@@ -0,0 +1,51 @@
+package org.oppia.android.util.parser
+
+import android.text.Editable
+import android.text.Spannable
+import android.text.SpannableStringBuilder
+import android.text.style.ClickableSpan
+import android.view.View
+import org.oppia.android.util.logging.ConsoleLogger
+import org.xml.sax.Attributes
+
+/** The custom tag corresponding to [ConceptCardTagHandler]. */
+const val CUSTOM_CONCEPT_CARD_TAG = "oppia-noninteractive-skillreview"
+
+// https://mohammedlakkadshaw.com/blog/handling-custom-tags-in-android-using-html-taghandler.html/
+class ConceptCardTagHandler(
+  private val listener: ConceptCardLinkClickListener,
+  private val consoleLogger: ConsoleLogger
+) : CustomHtmlContentHandler.CustomTagHandler {
+  override fun handleTag(
+    attributes: Attributes,
+    openIndex: Int,
+    closeIndex: Int,
+    output: Editable,
+    imageRetriever: CustomHtmlContentHandler.ImageRetriever
+  ) {
+    // Replace the custom tag with a clickable piece of text based on the tag's customizations.
+    val skillId = attributes.getJsonStringValue("skill_id-with-value")
+    val text = attributes.getJsonStringValue("text-with-value")
+    if (skillId != null && text != null) {
+      val spannableBuilder = SpannableStringBuilder(text)
+      spannableBuilder.setSpan(
+        object : ClickableSpan() {
+          override fun onClick(view: View) {
+            listener.onConceptCardLinkClicked(view, skillId)
+          }
+        },
+        /* start= */ 0, /* end= */ text.length, Spannable.SPAN_INCLUSIVE_EXCLUSIVE
+      )
+      output.replace(openIndex, closeIndex, spannableBuilder)
+    } else consoleLogger.e("ConceptCardTagHandler", "Failed to parse concept card tag")
+  }
+
+  /** Listener called when concept card links are clicked. */
+  interface ConceptCardLinkClickListener {
+    /**
+     * Called when a concept card link is called in the specified view corresponding to the
+     * specified skill ID.
+     */
+    fun onConceptCardLinkClicked(view: View, skillId: String)
+  }
+}
diff --git a/utility/src/main/java/org/oppia/android/util/parser/CustomHtmlContentHandler.kt b/utility/src/main/java/org/oppia/android/util/parser/CustomHtmlContentHandler.kt
@@ -1,5 +1,6 @@
 package org.oppia.android.util.parser
 
+import android.graphics.drawable.Drawable
 import android.text.Editable
 import android.text.Html
 import android.text.Spannable
@@ -17,7 +18,8 @@ import java.util.ArrayDeque
  * This is based on the implementation provided in https://stackoverflow.com/a/36528149.
  */
 class CustomHtmlContentHandler private constructor(
-  private val customTagHandlers: Map<String, CustomTagHandler>
+  private val customTagHandlers: Map<String, CustomTagHandler>,
+  private val imageRetriever: ImageRetriever
 ) : ContentHandler, Html.TagHandler {
   private var originalContentHandler: ContentHandler? = null
   private var currentTrackedTag: TrackedTag? = null
@@ -107,7 +109,8 @@ class CustomHtmlContentHandler private constructor(
         }
         val (_, attributes, openTagIndex) = currentTrackedCustomTag
         customTagHandlers.getValue(tag).handleClosingTag(output)
-        customTagHandlers.getValue(tag).handleTag(attributes, openTagIndex, output.length, output)
+        customTagHandlers.getValue(tag)
+          .handleTag(attributes, openTagIndex, output.length, output, imageRetriever)
       }
     }
   }
@@ -128,8 +131,16 @@ class CustomHtmlContentHandler private constructor(
      * @param openIndex the index in the output [Editable] at which this tag begins
      * @param closeIndex the index in the output [Editable] at which this tag ends
      * @param output the destination [Editable] to which spans can be added
+     * @param imageRetriever a utility to load image drawables if needed by the handler
      */
-    fun handleTag(attributes: Attributes, openIndex: Int, closeIndex: Int, output: Editable) {}
+    fun handleTag(
+      attributes: Attributes,
+      openIndex: Int,
+      closeIndex: Int,
+      output: Editable,
+      imageRetriever: ImageRetriever
+    ) {
+    }
 
     /**
      * Called when the opening of a custom tag is encountered. This does not support processing
@@ -152,25 +163,54 @@ class CustomHtmlContentHandler private constructor(
     fun handleClosingTag(output: Editable) {}
   }
 
+  /**
+   * Retriever of images for custom tag handlers. The built-in Android analog for this class is
+   * Html's ImageGetter.
+   */
+  interface ImageRetriever {
+    /** Returns a new [Drawable] corresponding to the specified URL and [Type]. */
+    fun loadDrawable(sourceUrl: String, type: Type): Drawable
+
+    /** Corresponds to the types of images that can be retrieved. */
+    enum class Type {
+      /**
+       * Corresponds to a block image that should be positioned in a way that may break text, and
+       * potentially centered depending on the configuration of the implementation.
+       */
+      BLOCK_IMAGE
+    }
+  }
+
   companion object {
     /**
-     * Returns a new [Spannable] with HTML parsed from [html] using the specified [imageGetter] for
-     * handling image retrieval, and map of tags to [CustomTagHandler]s for handling custom tags.
-     * All possible custom tags must be registered in the [customTagHandlers] map.
+     * Returns a new [Spannable] with HTML parsed from [html] using the specified [imageRetriever]
+     * for handling image retrieval, and map of tags to [CustomTagHandler]s for handling custom
+     * tags. All possible custom tags must be registered in the [customTagHandlers] map.
      */
-    fun fromHtml(
+    fun <T> fromHtml(
       html: String,
-      imageGetter: Html.ImageGetter,
+      imageRetriever: T,
       customTagHandlers: Map<String, CustomTagHandler>
-    ): Spannable {
+    ): Spannable where T : Html.ImageGetter, T : ImageRetriever {
       // Adjust the HTML to allow the custom content handler to properly initialize custom tag
       // tracking.
       return HtmlCompat.fromHtml(
         "<init-custom-handler/>$html",
         HtmlCompat.FROM_HTML_MODE_LEGACY,
-        imageGetter,
-        CustomHtmlContentHandler(customTagHandlers)
+        imageRetriever,
+        CustomHtmlContentHandler(customTagHandlers, imageRetriever),
       ) as Spannable
     }
   }
 }
+
+/**
+ * Returns a string value from this [Attributes] object, but interpreted as a JSON string, or null
+ * if the corresponding value doesn't exist in this attributes map.
+ */
+fun Attributes.getJsonStringValue(name: String): String? {
+  // Note that the attribute is actually an encoded JSON string (so it has escaped quotes around
+  // it). Since it's only a source string, the quotes can simply be removed in order to extract
+  // the string value.
+  return getValue(name)?.replace("&quot;", "")
+}
diff --git a/utility/src/main/java/org/oppia/android/util/parser/HtmlParser.kt b/utility/src/main/java/org/oppia/android/util/parser/HtmlParser.kt
@@ -1,33 +1,35 @@
 package org.oppia.android.util.parser
 
-import android.text.Editable
 import android.text.Spannable
 import android.text.SpannableStringBuilder
 import android.text.method.LinkMovementMethod
-import android.text.style.ClickableSpan
 import android.view.View
 import android.widget.TextView
-import org.xml.sax.Attributes
+import org.oppia.android.util.logging.ConsoleLogger
 import javax.inject.Inject
 
-private const val CUSTOM_IMG_TAG = "oppia-noninteractive-image"
-private const val REPLACE_IMG_TAG = "img"
-private const val CUSTOM_IMG_FILE_PATH_ATTRIBUTE = "filepath-with-value"
-private const val REPLACE_IMG_FILE_PATH_ATTRIBUTE = "src"
-
-private const val CUSTOM_CONCEPT_CARD_TAG = "oppia-noninteractive-skillreview"
-
 /** Html Parser to parse custom Oppia tags with Android-compatible versions. */
 class HtmlParser private constructor(
   private val urlImageParserFactory: UrlImageParser.Factory,
   private val gcsResourceName: String,
   private val entityType: String,
   private val entityId: String,
   private val imageCenterAlign: Boolean,
+  private val consoleLogger: ConsoleLogger,
   customOppiaTagActionListener: CustomOppiaTagActionListener?
 ) {
-  private val conceptCardTagHandler = ConceptCardTagHandler(customOppiaTagActionListener)
-  private val bulletTagHandler = BulletTagHandler()
+  private val conceptCardTagHandler by lazy {
+    ConceptCardTagHandler(
+      object : ConceptCardTagHandler.ConceptCardLinkClickListener {
+        override fun onConceptCardLinkClicked(view: View, skillId: String) {
+          customOppiaTagActionListener?.onConceptCardLinkClicked(view, skillId)
+        }
+      },
+      consoleLogger
+    )
+  }
+  private val bulletTagHandler by lazy { BulletTagHandler() }
+  private val imageTagHandler by lazy { ImageTagHandler(consoleLogger) }
 
   /**
    * Parses a raw HTML string with support for custom Oppia tags.
@@ -57,13 +59,6 @@ class HtmlParser private constructor(
         .replace("</li>", "</$CUSTOM_BULLET_LIST_TAG>")
     }
 
-    if (CUSTOM_IMG_TAG in htmlContent) {
-      htmlContent = htmlContent.replace(CUSTOM_IMG_TAG, REPLACE_IMG_TAG)
-      htmlContent =
-        htmlContent.replace(CUSTOM_IMG_FILE_PATH_ATTRIBUTE, REPLACE_IMG_FILE_PATH_ATTRIBUTE)
-      htmlContent = htmlContent.replace("&amp;quot;", "")
-    }
-
     // https://stackoverflow.com/a/8662457
     if (supportsLinks) {
       htmlContentTextView.movementMethod = LinkMovementMethod.getInstance()
@@ -88,38 +83,13 @@ class HtmlParser private constructor(
   ): Map<String, CustomHtmlContentHandler.CustomTagHandler> {
     val handlersMap = mutableMapOf<String, CustomHtmlContentHandler.CustomTagHandler>()
     handlersMap[CUSTOM_BULLET_LIST_TAG] = bulletTagHandler
+    handlersMap[CUSTOM_IMG_TAG] = imageTagHandler
     if (supportsConceptCards) {
       handlersMap[CUSTOM_CONCEPT_CARD_TAG] = conceptCardTagHandler
     }
     return handlersMap
   }
 
-  // https://mohammedlakkadshaw.com/blog/handling-custom-tags-in-android-using-html-taghandler.html/
-  private class ConceptCardTagHandler(
-    private val customOppiaTagActionListener: CustomOppiaTagActionListener?
-  ) : CustomHtmlContentHandler.CustomTagHandler {
-    override fun handleTag(
-      attributes: Attributes,
-      openIndex: Int,
-      closeIndex: Int,
-      output: Editable
-    ) {
-      // Replace the custom tag with a clickable piece of text based on the tag's customizations.
-      val skillId = attributes.getValue("skill_id-with-value")
-      val text = attributes.getValue("text-with-value")
-      val spannableBuilder = SpannableStringBuilder(text)
-      spannableBuilder.setSpan(
-        object : ClickableSpan() {
-          override fun onClick(view: View) {
-            customOppiaTagActionListener?.onConceptCardLinkClicked(view, skillId)
-          }
-        },
-        0, text.length, Spannable.SPAN_INCLUSIVE_EXCLUSIVE
-      )
-      output.replace(openIndex, closeIndex, spannableBuilder)
-    }
-  }
-
   private fun trimSpannable(spannable: SpannableStringBuilder): SpannableStringBuilder {
     val trimmedText = spannable.toString()
     val trimStart = if (trimmedText.startsWith("\n")) 1 else 0
@@ -150,7 +120,10 @@ class HtmlParser private constructor(
   }
 
   /** Factory for creating new [HtmlParser]s. */
-  class Factory @Inject constructor(private val urlImageParserFactory: UrlImageParser.Factory) {
+  class Factory @Inject constructor(
+    private val urlImageParserFactory: UrlImageParser.Factory,
+    private val consoleLogger: ConsoleLogger
+  ) {
     /**
      * Returns a new [HtmlParser] with the specified entity type and ID for loading images, and an
      * optionally specified [CustomOppiaTagActionListener] for handling custom Oppia tag events.
@@ -168,6 +141,7 @@ class HtmlParser private constructor(
         entityType,
         entityId,
         imageCenterAlign,
+        consoleLogger,
         customOppiaTagActionListener
       )
     }