From c8824763f6adea5149a454c0524b8a054a6754a2 Mon Sep 17 00:00:00 2001
From: Daniel Egger <daniel.egger@gmail.com>
Date: Fri, 21 Oct 2022 09:50:25 +0200
Subject: [PATCH] Refactor types

---
 .../learningPath/LearningContentTypeBadge.vue |  37 +--
 .../competence/PerformanceCriteriaPage.vue    |   3 +-
 client/src/services/circle.ts                 |  70 ++--
 client/src/services/learningPath.ts           |  18 +-
 client/src/stores/competence.ts               |  10 +-
 client/src/stores/completion.ts               |   4 +-
 client/src/types.ts                           | 312 ++++++++----------
 client/src/utils/typeMaps.ts                  |  42 ++-
 client/src/utils/utils.ts                     |   3 +
 .../learnpath/create_default_learning_path.py |   2 +-
 .../learnpath/models_learning_unit_content.py |  16 +-
 11 files changed, 230 insertions(+), 287 deletions(-)
 create mode 100644 client/src/utils/utils.ts

diff --git a/client/src/components/learningPath/LearningContentTypeBadge.vue b/client/src/components/learningPath/LearningContentTypeBadge.vue
index 63dcd50f..aa25a649 100644
--- a/client/src/components/learningPath/LearningContentTypeBadge.vue
+++ b/client/src/components/learningPath/LearningContentTypeBadge.vue
@@ -1,6 +1,6 @@
 <script setup lang="ts">
 import type { LearningContentType } from "@/types";
-import { learningContentTypesToName } from "@/utils/typeMaps";
+import { learningContentTypeData } from "@/utils/typeMaps";
 
 const props = defineProps<{
   learningContentType: LearningContentType;
@@ -11,39 +11,12 @@ const props = defineProps<{
   <div
     class="flex bg-gray-200 rounded-full px-2.5 py-0.5 gap-2 items-center w-min h-min"
   >
-    <it-icon-lc-assignment
-      v-if="props.learningContentType === 'assignment'"
+    <component
+      :is="learningContentTypeData(props.learningContentType).icon"
       class="w-6 h-6"
-    />
-    <it-icon-lc-exercise
-      v-else-if="props.learningContentType === 'exercise'"
-      class="w-6 h-6"
-    />
-    <it-icon-lc-book v-else-if="props.learningContentType === 'book'" class="w-6 h-6" />
-    <it-icon-lc-video
-      v-else-if="props.learningContentType === 'video'"
-      class="w-6 h-6"
-    />
-    <it-icon-lc-media-library
-      v-else-if="props.learningContentType === 'media_library'"
-      class="w-6 h-6"
-    />
-    <it-icon-lc-test v-else-if="props.learningContentType === 'test'" class="w-6 h-6" />
-    <it-icon-lc-online-training
-      v-else-if="props.learningContentType === 'online_training'"
-      class="w-6 h-6"
-    />
-    <it-icon-lc-resource
-      v-else-if="props.learningContentType === 'resource'"
-      class="w-6 h-6"
-    />
-    <it-icon-lc-resource
-      v-else-if="props.learningContentType === 'document'"
-      class="w-6 h-6"
-    />
-    <it-icon-lc-document v-else class="w-6 h-6" />
+    ></component>
     <p class="whitespace-nowrap">
-      {{ learningContentTypesToName.get(props.learningContentType) }}
+      {{ learningContentTypeData(props.learningContentType).title }}
     </p>
   </div>
 </template>
diff --git a/client/src/pages/competence/PerformanceCriteriaPage.vue b/client/src/pages/competence/PerformanceCriteriaPage.vue
index 26b48cda..b5bbe32c 100644
--- a/client/src/pages/competence/PerformanceCriteriaPage.vue
+++ b/client/src/pages/competence/PerformanceCriteriaPage.vue
@@ -4,7 +4,8 @@ import ItDropdownSelect from "@/components/ui/ItDropdownSelect.vue";
 import { useCompetenceStore } from "@/stores/competence";
 import type { CourseCompletionStatus } from "@/types";
 import * as log from "loglevel";
-import { computed, Ref, ref } from "vue";
+import type { Ref } from "vue";
+import { computed, ref } from "vue";
 
 log.debug("CompetencesMainView created");
 
diff --git a/client/src/services/circle.ts b/client/src/services/circle.ts
index 12bbeffb..3edb0d5f 100644
--- a/client/src/services/circle.ts
+++ b/client/src/services/circle.ts
@@ -4,34 +4,13 @@ import type {
   CircleGoal,
   CircleJobSituation,
   CourseCompletion,
-  CourseCompletionStatus,
-  CourseWagtailPage,
   LearningContent,
   LearningSequence,
   LearningUnit,
   LearningUnitPerformanceCriteria,
+  WagtailCircle,
 } from "@/types";
 
-function _createEmptyLearningUnit(
-  parentLearningSequence: LearningSequence
-): LearningUnit {
-  return {
-    id: 0,
-    title: "",
-    slug: "",
-    translation_key: "",
-    type: "learnpath.LearningUnit",
-    frontend_url: "",
-    learningContents: [],
-    minutes: 0,
-    parentLearningSequence: parentLearningSequence,
-    children: [],
-    last: true,
-    completion_status: "unknown",
-    evaluate_url: "",
-  };
-}
-
 export function parseLearningSequences(
   circle: Circle,
   children: CircleChild[]
@@ -52,9 +31,6 @@ export function parseLearningSequences(
         result.push(learningSequence);
       }
       learningSequence = Object.assign(child, { learningUnits: [] });
-
-      // initialize empty learning unit if there will not come a learning unit next
-      learningUnit = _createEmptyLearningUnit(learningSequence);
     } else if (child.type === "learnpath.LearningUnit") {
       if (!learningSequence) {
         throw new Error("LearningUnit found before LearningSequence");
@@ -92,13 +68,15 @@ export function parseLearningSequences(
       }
 
       learningUnit.learningContents.push(child);
+    } else {
+      throw new Error("Unknown CircleChild found...");
     }
   });
 
   if (learningUnit && learningSequence) {
     // TypeScript does not get it here...
     learningUnit.last = true;
-    (learningSequence as LearningSequence).learningUnits.push(learningUnit);
+    learningSequence.learningUnits.push(learningUnit);
     result.push(learningSequence);
   } else {
     throw new Error(
@@ -121,10 +99,9 @@ export function parseLearningSequences(
   return result;
 }
 
-export class Circle implements CourseWagtailPage {
+export class Circle implements WagtailCircle {
   readonly type = "learnpath.Circle";
   readonly learningSequences: LearningSequence[];
-  completion_status: CourseCompletionStatus = "unknown";
 
   nextCircle?: Circle;
   previousCircle?: Circle;
@@ -136,30 +113,33 @@ export class Circle implements CourseWagtailPage {
     public readonly translation_key: string,
     public readonly frontend_url: string,
     public readonly description: string,
-    public children: CircleChild[],
-    public goal_description: string,
-    public goals: CircleGoal[],
-    public job_situation_description: string,
-    public job_situations: CircleJobSituation[],
+    public readonly children: CircleChild[],
+    public readonly goal_description: string,
+    public readonly goals: CircleGoal[],
+    public readonly job_situation_description: string,
+    public readonly job_situations: CircleJobSituation[],
     public readonly parentLearningPath?: LearningPath
   ) {
     this.learningSequences = parseLearningSequences(this, this.children);
   }
 
-  public static fromJson(json: any, learningPath?: LearningPath): Circle {
+  public static fromJson(
+    wagtailCircle: WagtailCircle,
+    learningPath?: LearningPath
+  ): Circle {
     // TODO add error checking when the data does not conform to the schema
     return new Circle(
-      json.id,
-      json.slug,
-      json.title,
-      json.translation_key,
-      json.frontend_url,
-      json.description,
-      json.children,
-      json.goal_description,
-      json.goals,
-      json.job_situation_description,
-      json.job_situations,
+      wagtailCircle.id,
+      wagtailCircle.slug,
+      wagtailCircle.title,
+      wagtailCircle.translation_key,
+      wagtailCircle.frontend_url,
+      wagtailCircle.description,
+      wagtailCircle.children,
+      wagtailCircle.goal_description,
+      wagtailCircle.goals,
+      wagtailCircle.job_situation_description,
+      wagtailCircle.job_situations,
       learningPath
     );
   }
diff --git a/client/src/services/learningPath.ts b/client/src/services/learningPath.ts
index eafdf083..79bdae91 100644
--- a/client/src/services/learningPath.ts
+++ b/client/src/services/learningPath.ts
@@ -2,12 +2,12 @@ import * as _ from "lodash";
 
 import { Circle } from "@/services/circle";
 import type {
+  Course,
   CourseCompletion,
-  CourseCompletionStatus,
-  CourseWagtailPage,
   LearningContent,
   LearningPathChild,
   Topic,
+  WagtailLearningPath,
 } from "@/types";
 
 function getLastCompleted(courseId: number, completionData: CourseCompletion[]) {
@@ -22,21 +22,23 @@ function getLastCompleted(courseId: number, completionData: CourseCompletion[])
   );
 }
 
-export class LearningPath implements CourseWagtailPage {
+export class LearningPath implements WagtailLearningPath {
   readonly type = "learnpath.LearningPath";
   public topics: Topic[];
   public circles: Circle[];
   public nextLearningContent?: LearningContent;
-  readonly completion_status: CourseCompletionStatus = "unknown";
 
-  public static fromJson(json: any, completionData: CourseCompletion[]): LearningPath {
+  public static fromJson(
+    json: WagtailLearningPath,
+    completionData: CourseCompletion[]
+  ): LearningPath {
     return new LearningPath(
       json.id,
       json.slug,
       json.course.title,
       json.translation_key,
       json.frontend_url,
-      json.course.id,
+      json.course,
       json.children,
       completionData
     );
@@ -48,7 +50,7 @@ export class LearningPath implements CourseWagtailPage {
     public readonly title: string,
     public readonly translation_key: string,
     public readonly frontend_url: string,
-    public readonly courseId: number,
+    public readonly course: Course,
     public children: LearningPathChild[],
     completionData?: CourseCompletion[]
   ) {
@@ -95,7 +97,7 @@ export class LearningPath implements CourseWagtailPage {
     this.nextLearningContent = undefined;
 
     const lastCompletedLearningContent = getLastCompleted(
-      this.courseId,
+      this.course.id,
       completionData
     );
 
diff --git a/client/src/stores/competence.ts b/client/src/stores/competence.ts
index a133c45a..c13c73df 100644
--- a/client/src/stores/competence.ts
+++ b/client/src/stores/competence.ts
@@ -1,9 +1,9 @@
 import { itGet } from "@/fetchHelpers";
 import { useCompletionStore } from "@/stores/completion";
 import type {
+  BaseCourseWagtailPage,
   CompetencePage,
   CompetenceProfilePage,
-  CourseWagtailPage,
   PerformanceCriteria,
 } from "@/types";
 import _ from "lodash";
@@ -103,9 +103,11 @@ export const useCompetenceStore = defineStore({
 
       this.competenceProfilePage = competenceProfilePageData;
 
-      const circles = competenceProfilePageData.circles.map((c: CourseWagtailPage) => {
-        return { id: c.translation_key, name: `Circle: ${c.title}` };
-      });
+      const circles = competenceProfilePageData.circles.map(
+        (c: BaseCourseWagtailPage) => {
+          return { id: c.translation_key, name: `Circle: ${c.title}` };
+        }
+      );
       this.availableCircles = [{ id: "all", name: "Circle: Alle" }, ...circles];
 
       await this.parseCompletionData();
diff --git a/client/src/stores/completion.ts b/client/src/stores/completion.ts
index f420ac0d..e6e25ff0 100644
--- a/client/src/stores/completion.ts
+++ b/client/src/stores/completion.ts
@@ -1,5 +1,5 @@
 import { itGet, itPost } from "@/fetchHelpers";
-import type { CourseCompletion, CourseWagtailPage } from "@/types";
+import type { BaseCourseWagtailPage, CourseCompletion } from "@/types";
 import { defineStore } from "pinia";
 
 export type CompletionStoreState = {
@@ -28,7 +28,7 @@ export const useCompletionStore = defineStore({
       this.completionData = completionData;
       return this.completionData || [];
     },
-    async markPage(page: CourseWagtailPage) {
+    async markPage(page: BaseCourseWagtailPage) {
       const completionData = await itPost("/api/course/completion/mark/", {
         page_key: page.translation_key,
         completion_status: page.completion_status,
diff --git a/client/src/types.ts b/client/src/types.ts
index b1091352..6a5c1853 100644
--- a/client/src/types.ts
+++ b/client/src/types.ts
@@ -3,105 +3,133 @@ import type { Component } from "vue";
 
 export type CourseCompletionStatus = "unknown" | "fail" | "success";
 
-export type LearningContentType =
-  | "assignment"
-  | "book"
-  | "document"
-  | "exercise"
-  | "media_library"
-  | "online_training"
-  | "resource"
-  | "test"
-  | "video"
-  | "placeholder";
 
-export interface LearningContentBlock {
-  type: LearningContentType;
-  value: {
-    description: string;
-  };
-  id: string;
+export interface BaseCourseWagtailPage {
+  readonly id: number;
+  readonly title: string;
+  readonly slug: string;
+  readonly type: string;
+  readonly translation_key: string;
+  readonly frontend_url: string;
+  completion_status?: CourseCompletionStatus;
+  completion_status_updated_at?: string;
 }
 
-export interface AssignmentBlock {
-  type: "assignment";
-  value: {
-    description: string;
-    url: string;
-  };
-  id: string;
+export interface CircleLight {
+  readonly id: number;
+  readonly title: string;
+  readonly translation_key: string;
 }
 
-export interface BookBlock {
-  type: "book";
-  value: {
+export interface BaseLearningContentBlock {
+  readonly type: string;
+  readonly id: string;
+  readonly value: {
     description: string;
     url: string;
+    text?: string;
   };
-  id: string;
 }
 
-export interface DocumentBlock {
-  type: "document";
-  value: {
-    description: string;
-    url: string;
-  };
-  id: string;
+export interface AssignmentBlock extends BaseLearningContentBlock {
+  readonly type: "assignment";
 }
 
-export interface ExerciseBlock {
-  type: "exercise";
-  value: {
-    description: string;
-    url: string;
-  };
-  id: string;
+export interface BookBlock extends BaseLearningContentBlock {
+  readonly type: "book";
 }
 
-export interface MediaLibraryBlock {
-  type: "media_library";
-  value: {
-    description: string;
-    url: string;
-  };
-  id: string;
+export interface DocumentBlock extends BaseLearningContentBlock {
+  readonly type: "document";
 }
 
-export interface OnlineTrainingBlock {
-  type: "online_training";
-  value: {
-    description: string;
-    url: string;
-  };
-  id: string;
+export interface ExerciseBlock extends BaseLearningContentBlock {
+  readonly type: "exercise";
 }
 
-export interface ResourceBlock {
-  type: "resource";
-  value: {
-    description: string;
-    url: string;
-  };
-  id: string;
+export interface MediaLibraryBlock extends BaseLearningContentBlock {
+  readonly type: "media_library";
 }
 
-export interface TestBlock {
-  type: "test";
-  value: {
-    description: string;
-    url: string;
-  };
-  id: string;
+export interface OnlineTrainingBlock extends BaseLearningContentBlock {
+  readonly type: "online_training";
 }
 
-export interface VideoBlock {
-  type: "video";
-  value: {
-    description: string;
-    url: string;
-  };
-  id: string;
+export interface ResourceBlock extends BaseLearningContentBlock {
+  readonly type: "resource";
+}
+
+export interface TestBlock extends BaseLearningContentBlock {
+  readonly type: "test";
+}
+
+export interface VideoBlock extends BaseLearningContentBlock {
+  readonly type: "video";
+}
+
+export interface PlaceholderBlock extends BaseLearningContentBlock {
+  readonly type: "placeholder";
+}
+
+export type LearningContentBlock =
+  | AssignmentBlock
+  | BookBlock
+  | DocumentBlock
+  | ExerciseBlock
+  | MediaLibraryBlock
+  | OnlineTrainingBlock
+  | ResourceBlock
+  | TestBlock
+  | VideoBlock
+  | PlaceholderBlock;
+
+export type LearningContentType = LearningContentBlock["type"];
+
+export interface LearningContent extends BaseCourseWagtailPage {
+  readonly type: "learnpath.LearningContent";
+  minutes: number;
+  contents: LearningContentBlock[];
+  parentCircle: Circle;
+  parentLearningSequence?: LearningSequence;
+  parentLearningUnit?: LearningUnit;
+  nextLearningContent?: LearningContent;
+  previousLearningContent?: LearningContent;
+}
+
+export interface LearningUnitPerformanceCriteria extends BaseCourseWagtailPage {
+  readonly type: "competence.PerformanceCriteria";
+  readonly competence_id: string;
+  parentLearningSequence?: LearningSequence;
+  parentLearningUnit?: LearningUnit;
+}
+
+export interface LearningUnit extends BaseCourseWagtailPage {
+  readonly type: "learnpath.LearningUnit";
+  readonly evaluate_url: string;
+  readonly course_category: CourseCategory;
+  children: LearningUnitPerformanceCriteria[];
+
+  // additional frontend fields
+  learningContents: LearningContent[];
+  minutes: number;
+  parentLearningSequence?: LearningSequence;
+  parentCircle?: Circle;
+  last?: boolean;
+}
+
+export interface LearningSequence extends BaseCourseWagtailPage {
+  readonly type: "learnpath.LearningSequence";
+  icon: string;
+  learningUnits: LearningUnit[];
+  minutes: number;
+}
+
+export type CircleChild = LearningContent | LearningUnit | LearningSequence;
+
+export interface WagtailLearningPath extends BaseCourseWagtailPage {
+  readonly type: "learnpath.LearningPath";
+  course: Course;
+  children: LearningPathChild[];
 }
 
 export interface CircleGoal {
@@ -116,83 +144,19 @@ export interface CircleJobSituation {
   id: string;
 }
 
-export interface CourseWagtailPage {
-  readonly id: number;
-  readonly title: string;
-  readonly slug: string;
-  readonly translation_key: string;
-  readonly frontend_url: string;
-  completion_status: CourseCompletionStatus;
-  completion_status_updated_at?: string;
+export interface WagtailCircle extends BaseCourseWagtailPage {
+  readonly type: "learnpath.Circle";
+  readonly description: string;
+  readonly goal_description: string;
+  readonly goals: CircleGoal[];
+  readonly job_situation_description: string;
+  readonly job_situations: CircleJobSituation[];
+  readonly children: CircleChild[];
 }
 
-export interface CircleLight {
-  readonly id: number;
-  readonly title: string;
-  readonly slug: string;
-  readonly translation_key: string;
-}
-
-export interface LearningContent extends CourseWagtailPage {
-  type: "learnpath.LearningContent";
-  minutes: number;
-  contents: (
-    | AssignmentBlock
-    | BookBlock
-    | DocumentBlock
-    | ExerciseBlock
-    | MediaLibraryBlock
-    | OnlineTrainingBlock
-    | ResourceBlock
-    | TestBlock
-    | VideoBlock
-  )[];
-  parentCircle: Circle;
-  parentLearningSequence?: LearningSequence;
-  parentLearningUnit?: LearningUnit;
-  nextLearningContent?: LearningContent;
-  previousLearningContent?: LearningContent;
-}
-
-export interface LearningUnitPerformanceCriteria extends CourseWagtailPage {
-  type: "competence.PerformanceCriteria";
-  parentLearningSequence?: LearningSequence;
-  parentLearningUnit?: LearningUnit;
-}
-
-export interface LearningUnit extends CourseWagtailPage {
-  type: "learnpath.LearningUnit";
-  learningContents: LearningContent[];
-  evaluate_url: string;
-  minutes: number;
-  parentLearningSequence?: LearningSequence;
-  parentCircle?: Circle;
-  children: LearningUnitPerformanceCriteria[];
-  last?: boolean;
-}
-
-export interface LearningSequence extends CourseWagtailPage {
-  type: "learnpath.LearningSequence";
-  icon: string;
-  learningUnits: LearningUnit[];
-  minutes: number;
-}
-
-export type CircleChild =
-  | LearningContent
-  | LearningUnit
-  | LearningSequence
-  | LearningUnitPerformanceCriteria;
-
-export interface WagtailCircle extends CourseWagtailPage {
-  type: "learnpath.Circle";
-  children: CircleChild[];
-  description: string;
-}
-
-export interface Topic extends CourseWagtailPage {
-  type: "learnpath.Topic";
-  is_visible: boolean;
+export interface Topic extends BaseCourseWagtailPage {
+  readonly type: "learnpath.Topic";
+  readonly is_visible: boolean;
   circles: Circle[];
 }
 
@@ -208,7 +172,7 @@ export interface CourseCompletion {
   page_slug: string;
   course: number;
   completion_status: CourseCompletionStatus;
-  additional_json_data: any;
+  additional_json_data: unknown;
 }
 
 export interface CircleDiagramData {
@@ -224,7 +188,7 @@ export interface CircleDiagramData {
 
 export interface Course {
   id: number;
-  name: string;
+  title: string;
   category_name: string;
 }
 
@@ -280,7 +244,7 @@ export interface MediaContentCollection {
   };
 }
 
-export interface MediaCategoryPage extends CourseWagtailPage {
+export interface MediaCategoryPage extends BaseCourseWagtailPage {
   type: "media_library.MediaCategoryPage";
   overview_icon: string;
   introduction_text: string;
@@ -295,31 +259,31 @@ export interface MediaCategoryPage extends CourseWagtailPage {
   body: MediaContentCollection[];
 }
 
-export interface MediaLibraryPage extends CourseWagtailPage {
-  type: "media_library.MediaLibraryPage";
-  course: Course;
-  children: MediaCategoryPage[];
+export interface MediaLibraryPage extends BaseCourseWagtailPage {
+  readonly type: "media_library.MediaLibraryPage";
+  readonly course: Course;
+  readonly children: MediaCategoryPage[];
 }
 
-export interface PerformanceCriteria extends CourseWagtailPage {
-  type: "competence.PerformanceCriteria";
-  competence_id: string;
-  circle: CircleLight;
-  course_category: CourseCategory;
-  learning_unit: CourseWagtailPage;
+export interface PerformanceCriteria extends BaseCourseWagtailPage {
+  readonly type: "competence.PerformanceCriteria";
+  readonly competence_id: string;
+  readonly circle: CircleLight;
+  readonly course_category: CourseCategory;
+  readonly learning_unit: BaseCourseWagtailPage;
 }
 
-export interface CompetencePage extends CourseWagtailPage {
-  type: "competence.CompetencePage";
-  competence_id: string;
-  children: PerformanceCriteria[];
+export interface CompetencePage extends BaseCourseWagtailPage {
+  readonly type: "competence.CompetencePage";
+  readonly competence_id: string;
+  readonly children: PerformanceCriteria[];
 }
 
-export interface CompetenceProfilePage extends CourseWagtailPage {
-  type: "competence.CompetenceProfilePage";
-  course: Course;
-  circles: CircleLight[];
-  children: CompetencePage[];
+export interface CompetenceProfilePage extends BaseCourseWagtailPage {
+  readonly type: "competence.CompetenceProfilePage";
+  readonly course: Course;
+  readonly circles: CircleLight[];
+  readonly children: CompetencePage[];
 }
 
 // dropdown
diff --git a/client/src/utils/typeMaps.ts b/client/src/utils/typeMaps.ts
index 790c6a6a..1a796538 100644
--- a/client/src/utils/typeMaps.ts
+++ b/client/src/utils/typeMaps.ts
@@ -1,14 +1,32 @@
 import type { LearningContentType } from "@/types";
+import { assertUnreachable } from "@/utils/utils";
 
-export const learningContentTypesToName = new Map<LearningContentType, string>([
-  ["assignment", "Transferauftrag"],
-  ["book", "Buch"],
-  ["document", "Dokument"],
-  ["exercise", "Übung"],
-  ["media_library", "Mediathek"],
-  ["online_training", "Online-Training"],
-  ["video", "Video"],
-  ["test", "Test"],
-  ["resource", "Seite"],
-  ["placeholder", "In Umsetzung"],
-]);
+export function learningContentTypeData(t: LearningContentType): {
+  title: string;
+  icon: string;
+} {
+  switch (t) {
+    case "assignment":
+      return { title: "Transferauftrag", icon: "it-icon-lc-assignment" };
+    case "book":
+      return { title: "Buch", icon: "it-icon-lc-book" };
+    case "document":
+      return { title: "Dokument", icon: "it-icon-lc-document" };
+    case "exercise":
+      return { title: "Übung", icon: "it-icon-lc-exercise" };
+    case "media_library":
+      return { title: "Mediathek", icon: "it-icon-lc-media-library" };
+    case "online_training":
+      return { title: "Online-Training", icon: "it-icon-lc-online-training" };
+    case "video":
+      return { title: "Video", icon: "it-icon-lc-video" };
+    case "test":
+      return { title: "Test", icon: "it-icon-lc-test" };
+    case "resource":
+      return { title: "Ressource", icon: "it-icon-lc-resource" };
+    case "placeholder":
+      return { title: "In Umsetzung", icon: "it-icon-lc-document" };
+  }
+
+  return assertUnreachable(t);
+}
diff --git a/client/src/utils/utils.ts b/client/src/utils/utils.ts
new file mode 100644
index 00000000..966499f3
--- /dev/null
+++ b/client/src/utils/utils.ts
@@ -0,0 +1,3 @@
+export function assertUnreachable(x: never): never {
+  throw new Error("Didn't expect to get here");
+}
diff --git a/server/vbv_lernwelt/learnpath/create_default_learning_path.py b/server/vbv_lernwelt/learnpath/create_default_learning_path.py
index 7aad5a2a..2f4648f3 100644
--- a/server/vbv_lernwelt/learnpath/create_default_learning_path.py
+++ b/server/vbv_lernwelt/learnpath/create_default_learning_path.py
@@ -273,7 +273,7 @@ wichtige Grundlage für eine erfolgreiche Beziehung.
                 VideoBlockFactory(
                     url="https://onedrive.live.com/embed?cid=26E4A934B79DCE5E&resid=26E4A934B79DCE5E%2153350&authkey=AId6i7z_X8l2fHw",
                     description="In dieser Circle zeigt dir ein Fachexperte anhand von Kundensituationen, wie du erfolgreich"
-                                "den Kundenbedarf ermitteln, analysieren, priorisieren und anschliessend zusammenfassen kannst.",
+                    "den Kundenbedarf ermitteln, analysieren, priorisieren und anschliessend zusammenfassen kannst.",
                 ),
             )
         ],
diff --git a/server/vbv_lernwelt/learnpath/models_learning_unit_content.py b/server/vbv_lernwelt/learnpath/models_learning_unit_content.py
index c1a0356f..5926a272 100644
--- a/server/vbv_lernwelt/learnpath/models_learning_unit_content.py
+++ b/server/vbv_lernwelt/learnpath/models_learning_unit_content.py
@@ -26,14 +26,6 @@ class DocumentBlock(blocks.StructBlock):
         icon = "media"
 
 
-class PlaceholderBlock(blocks.StructBlock):
-    description = blocks.TextBlock()
-    url = blocks.TextBlock()
-
-    class Meta:
-        icon = "media"
-
-
 class ExerciseBlock(blocks.StructBlock):
     description = blocks.TextBlock()
     url = blocks.TextBlock()
@@ -82,3 +74,11 @@ class VideoBlock(blocks.StructBlock):
 
     class Meta:
         icon = "media"
+
+
+class PlaceholderBlock(blocks.StructBlock):
+    description = blocks.TextBlock()
+    url = blocks.TextBlock()
+
+    class Meta:
+        icon = "media"