Add support for choice on canvases

__tests__/fixtures/choice.json

@@ -0,0 +1,69 @@
+{
+  "@context": "http://iiif.io/api/presentation/3/context.json",
+  "id": "https://iiif.io/api/cookbook/recipe/0033-choice/manifest.json",
+  "type": "Manifest",
+  "label": {
+    "en": ["John Dee performing an experiment before Queen Elizabeth I."]
+  },
+  "items": [
+    {
+      "id": "https://iiif.io/api/cookbook/recipe/0033-choice/canvas/p1",
+      "type": "Canvas",
+      "height": 1271,
+      "width": 2000,
+      "items": [
+        {
+          "id": "https://iiif.io/api/cookbook/recipe/0033-choice/page/p1/1",
+          "type": "AnnotationPage",
+          "items": [
+            {
+              "id": "https://iiif.io/api/cookbook/recipe/0033-choice/annotation/p0001-image",
+              "type": "Annotation",
+              "motivation": "painting",
+              "body": {
+                "type": "Choice",
+                "items": [
+                  {
+                    "id": "https://iiif.io/api/image/3.0/example/reference/421e65be2ce95439b3ad6ef1f2ab87a9-dee-natural/full/max/0/default.jpg",
+                    "type": "Image",
+                    "format": "image/jpeg",
+                    "width": 2000,
+                    "height": 1271,
+                    "label": {
+                      "en": ["Natural Light"]
+                    },
+                    "service": [
+                      {
+                        "id": "https://iiif.io/api/image/3.0/example/reference/421e65be2ce95439b3ad6ef1f2ab87a9-dee-natural",
+                        "type": "ImageService3",
+                        "profile": "level1"
+                      }
+                    ]
+                  },
+                  {
+                    "id": "https://iiif.io/api/image/3.0/example/reference/421e65be2ce95439b3ad6ef1f2ab87a9-dee-xray/full/max/0/default.jpg",
+                    "type": "Image",
+                    "format": "image/jpeg",
+                    "width": 2000,
+                    "height": 1271,
+                    "label": {
+                      "en": ["X-Ray"]
+                    },
+                    "service": [
+                      {
+                        "id": "https://iiif.io/api/image/3.0/example/reference/421e65be2ce95439b3ad6ef1f2ab87a9-dee-xray",
+                        "type": "ImageService3",
+                        "profile": "level1"
+                      }
+                    ]
+                  }
+                ]
+              },
+              "target": "https://iiif.io/api/cookbook/recipe/0033-choice/canvas/p1"
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}

__tests__/helper.test.ts

@@ -10,6 +10,7 @@ const cookbookAnnotationsEmbedded = require("./fixtures/cookbook-annotations-emb
 const wunder = require("./fixtures/wunder-pres2.json");
 const brideMatch = require("./fixtures/bride-match.json");
 const brideDiff = require("./fixtures/bride-diff.json");
+const choice = require("./fixtures/choice.json");
 
 function mockFetch(status: number, data?: any) {
   const xhrMockObj = {
@@ -284,4 +285,68 @@ describe("Helper", () => {
     expect(externalResource.isProbed).toBe(true);
     expect(externalResource.isResponseHandled).toBe(false);
   });
+
+  test("hasChoices returns true for choice manifest", async () => {
+    const helper = await loadManifestJson(choice, {
+      manifestUri: choice.id,
+    });
+
+    expect(helper).toBeDefined();
+    expect(helper.hasChoices()).toBe(true);
+  });
+
+  test("getChoices returns correct number of choices", async () => {
+    const helper = await loadManifestJson(choice, {
+      manifestUri: choice.id,
+    });
+
+    const choices = helper.getChoices();
+    expect(choices).toBeDefined();
+    expect(choices.length).toBe(2);
+  });
+
+  test("getChoices returns items with correct labels", async () => {
+    const helper = await loadManifestJson(choice, {
+      manifestUri: choice.id,
+    });
+
+    const choices = helper.getChoices();
+    expect(choices[0].getLabel().getValue()).toBe("Natural Light");
+    expect(choices[1].getLabel().getValue()).toBe("X-Ray");
+  });
+
+  test("getActiveChoice returns first choice by default", async () => {
+    const helper = await loadManifestJson(choice, {
+      manifestUri: choice.id,
+    });
+
+    const activeChoice = helper.getActiveChoice();
+    expect(activeChoice).toBeDefined();
+    expect(activeChoice?.getLabel().getValue()).toBe("Natural Light");
+  });
+
+  test("getActiveChoice returns correct choice after choiceIndex update", async () => {
+    const helper = await loadManifestJson(choice, {
+      manifestUri: choice.id,
+    });
+
+    helper.choiceIndex = 1;
+    expect(helper.getActiveChoice()?.getLabel().getValue()).toBe("X-Ray");
+  });
+
+  test("hasChoices returns false for non-choice manifest", async () => {
+    const helper = await loadManifestJson(utexasRightsLogoReqStatement, {
+      manifestUri: utexasRightsLogoReqStatement.id,
+    });
+
+    expect(helper.hasChoices()).toBe(false);
+  });
+
+  test("getActiveChoice returns null when no choices present", async () => {
+    const helper = await loadManifestJson(utexasRightsLogoReqStatement, {
+      manifestUri: utexasRightsLogoReqStatement.id,
+    });
+
+    expect(helper.getActiveChoice()).toBeNull();
+  });
 });