Add GuidedNavigationDocument, GuidedNavigationObject helper functions

shared/src/publication/GuidedNavigation.ts

@@ -2,18 +2,58 @@ import {
   arrayfromJSONorString,
   setToArray,
 } from '../util/JSONParse';
+import { Links } from "./Link";
+
+export interface Clip {
+    audioResource: string;
+    fragmentId?: string;
+    start?: number;
+    end?: number;
+}
+
+/**
+ * Guided Navigation Document
+ * https://readium.org/guided-navigation/schema/document.schema.json
+ */
+export class GuidedNavigationDocument {
+    public readonly links?: Links;
+    public readonly guided?: GuidedNavigationObject[];
+
+    constructor(values: {
+        links?: Links;
+        guided?: GuidedNavigationObject[];
+    }) {
+        this.links = values.links;
+        this.guided = values.guided;
+    }
+
+    public static deserialize(json: any): GuidedNavigationDocument | undefined {
+        if (!json) return;
+        return new GuidedNavigationDocument({
+            links: Links.deserialize(json.links),
+            guided: GuidedNavigationObject.deserializeArray(json.guided),
+        });
+    }
+
+    public serialize(): any {
+        const json: any = {};
+        if (this.links !== undefined) json.links = this.links.serialize();
+        if (this.guided !== undefined) json.guided = this.guided.map(x => x.serialize());
+        return json;
+    }
+}
 
 /**
- * Guided Navigation Object for the Readium Web Publication Manifest.
+ * Guided Navigation Object
  * https://github.com/readium/guided-navigation/blob/main/schema/object.schema.json
  */
 
-export class GuidedNavigation {
+export class GuidedNavigationObject {
   /** References an audio resource or a fragment of it. */
   public readonly audioref?: string;
 
   /** Items that are children of the containing Guided Navigation Object. */
-  public readonly children?: GuidedNavigation[];
+  public readonly children?: GuidedNavigationObject[];
 
   /** References an image or a fragment of it. */
   public readonly imgref?: string;
@@ -32,7 +72,7 @@ export class GuidedNavigation {
     */
     constructor(values: {
         audioref?: string;
-        children?: GuidedNavigation[];
+        children?: GuidedNavigationObject[];
         imgref?: string;
         role?: Set<string>;
         text?: string;
@@ -47,15 +87,15 @@ export class GuidedNavigation {
     }
 
     /**
-     * Parses a [GuidedNavigation] from its RWPM JSON representation.
+     * Parses a [GuidedNavigationObject] from its RWPM JSON representation.
      *
-     * A GuidedNavigation object can be parsed from a single string, or a full-fledged object.
+     * A GuidedNavigationObject can be parsed from a single string, or a full-fledged object.
     */
-    public static deserialize(json: any): GuidedNavigation | undefined {
+    public static deserialize(json: any): GuidedNavigationObject | undefined {
         if (!json) return;
-        return new GuidedNavigation({
+        return new GuidedNavigationObject({
             audioref: json.audioref,
-            children: GuidedNavigation.deserializeArray(json.children),
+            children: GuidedNavigationObject.deserializeArray(json.children),
             imgref: json.imgref,
             role: json.role
             ? new Set<string>(arrayfromJSONorString(json.role))
@@ -65,8 +105,18 @@ export class GuidedNavigation {
         });
     }
 
+    /** 
+     * Parses a [GuidedNavigationObject] array from its RWPM JSON representation.
+    */
+    public static deserializeArray(json: any): GuidedNavigationObject[] | undefined {
+        if (!(json instanceof Array)) return;
+        return json
+            .map<GuidedNavigationObject>((item) => GuidedNavigationObject.deserialize(item) as GuidedNavigationObject)
+            .filter((x) => x !== undefined);
+    }
+
     /**
-     * Serializes a [GuidedNavigation] to its RWPM JSON representation.
+     * Serializes a [GuidedNavigationObject] to its RWPM JSON representation.
     */
     public serialize(): any {
         const json: any = {};
@@ -78,4 +128,49 @@ export class GuidedNavigation {
         if (this.textref !== undefined) json.textref = this.textref;
         return json;
     }
+
+    public get audioFile(): string | undefined {
+        return this.audioref?.split('#')[0];
+    }
+
+    public get audioTime(): string | undefined {
+        if(this.audioref?.includes('#')) {
+            return this.audioref.split('#', 2)[1];
+        }
+        return undefined;
+    }
+
+    public get textFile(): string | undefined {
+        return this.textref?.split('#')[0];
+    }
+
+    public get fragmentId(): string | undefined {
+        if(this.textref?.includes('#')) {
+            return this.textref.split('#', 2)[1];
+        }
+        return undefined;
+    }
+
+    public get clip(): Clip | undefined {
+        const audio = this.audioFile;
+        if(!audio) return undefined;
+        const time = this.audioTime;
+        const result = {
+            audioResource: audio,
+            fragmentId: this.fragmentId,
+        } as Clip;
+        if(!time) return result;
+        const times = this.parseTimer(time);
+        result.start = times[0];
+        result.end = times[1];
+        return result;
+    }
+
+    private parseTimer(times: string): [number?, number?] {
+        if(!times || !times.startsWith("t=")) return [undefined, undefined];
+        const ts = times.substring(2).split(',').map(t => parseInt(t));
+        if(ts.length === 1) return [isNaN(ts[0]) ? undefined : ts[0], undefined];
+        if(ts.length > 2) return [undefined, undefined];
+        return [isNaN(ts[0]) ? undefined : ts[0], isNaN(ts[1]) ? undefined : ts[1]];
+    }
 }

shared/src/publication/Publication.ts

@@ -10,7 +10,7 @@ import { Metadata } from './Metadata';
 import { EmptyFetcher, Fetcher } from '../fetcher/Fetcher';
 import { PublicationCollection } from './PublicationCollection';
 import { Resource } from '../fetcher/Resource';
-import { GuidedNavigation } from "./GuidedNavigation";
+import { GuidedNavigationDocument } from "./GuidedNavigation";
 import { URITemplate } from "../util";
 
 export type ServiceFactory = () => null;
@@ -93,7 +93,7 @@ export class Publication {
       .filter(l => l !== undefined) as Locator[]; // Filter out failures
   }
 
-  public async guideForLink(link: Link): Promise<GuidedNavigation | undefined> {
+  public async guideForLink(link: Link): Promise<GuidedNavigationDocument | undefined> {
     const findGNLink = (l: Link): Link | undefined => l.alternates?.findWithMediaType(
       'application/guided-navigation+json'
     );
@@ -135,7 +135,7 @@ export class Publication {
     const guidedNavigationJSON = (await this.get(new Link({
       href,
     })).readAsJSON());
-    return GuidedNavigation.deserialize(guidedNavigationJSON);
+    return GuidedNavigationDocument.deserialize(guidedNavigationJSON);
   }
 
   /**

shared/src/publication/index.ts

@@ -16,3 +16,4 @@ export * from './Publication';
 export * from './PublicationCollection';
 export * from './ReadingProgression';
 export * from './Subject';
+export * from './GuidedNavigation';