Merges pull request #15

Implement PublicationTree Data Structure

deno.lock

@@ -2862,6 +2862,22 @@
     }
   },
   "workspace": {
+    "dependencies": [
+      "npm:@nostr-dev-kit/ndk-cache-dexie@2.5",
+      "npm:@nostr-dev-kit/ndk@2.11",
+      "npm:@popperjs/core@2.11",
+      "npm:@tailwindcss/forms@0.5",
+      "npm:@tailwindcss/typography@0.5",
+      "npm:asciidoctor@3.0",
+      "npm:d3@7.9",
+      "npm:flowbite-svelte-icons@2.0",
+      "npm:flowbite-svelte@0.44",
+      "npm:flowbite@2.2",
+      "npm:he@1.2",
+      "npm:nostr-tools@2.10",
+      "npm:svelte@5.0",
+      "npm:tailwind-merge@2.5"
+    ],
     "packageJson": {
       "dependencies": [
         "npm:@nostr-dev-kit/ndk-cache-dexie@2.5",

src/lib/components/Preview.svelte

@@ -1,8 +1,9 @@
 <script lang='ts'>
   import { pharosInstance, SiblingSearchDirection } from '$lib/parser';
-  import { Button, ButtonGroup, CloseButton, Input, P, Textarea, Tooltip } from 'flowbite-svelte';
+  import { Button, ButtonGroup, CloseButton, Input, Textarea, Tooltip } from 'flowbite-svelte';
   import { CaretDownSolid, CaretUpSolid, EditOutline } from 'flowbite-svelte-icons';
   import Self from './Preview.svelte';
+  import { contentParagraph, sectionHeading } from '$lib/snippets/PublicationSnippets.svelte';
 
   // TODO: Fix move between parents.
 
@@ -206,7 +207,7 @@
           </Textarea>
         </form>
       {:else}
-        {@render contentParagraph(currentContent, publicationType)}
+        {@render contentParagraph(currentContent, publicationType, isSectionStart)}
       {/if}
     {/key}
   {:else}

src/lib/data_structures/lazy.ts

@@ -0,0 +1,16 @@
+export class Lazy<T> {
+  #value?: T;
+  #resolver: () => Promise<T>;
+
+  constructor(resolver: () => Promise<T>) {
+    this.#resolver = resolver;
+  }
+
+  async value(): Promise<T> {
+    if (!this.#value) {
+      this.#value = await this.#resolver();
+    }
+
+    return this.#value;
+  }
+}

src/lib/data_structures/publication_tree.ts

@@ -0,0 +1,430 @@
+import type NDK from "@nostr-dev-kit/ndk";
+import type { NDKEvent } from "@nostr-dev-kit/ndk";
+import { Lazy } from "./lazy.ts";
+import { findIndexAsync as _findIndexAsync } from '../utils.ts';
+
+enum PublicationTreeNodeType {
+  Root,
+  Branch,
+  Leaf,
+}
+
+interface PublicationTreeNode {
+  type: PublicationTreeNodeType;
+  address: string;
+  parent?: PublicationTreeNode;
+  children?: Array<Lazy<PublicationTreeNode>>;
+}
+
+export class PublicationTree implements AsyncIterable<NDKEvent> {
+  /**
+   * The root node of the tree.
+   */
+  #root: PublicationTreeNode;
+
+  /**
+   * A map of addresses in the tree to their corresponding nodes.
+   */
+  #nodes: Map<string, Lazy<PublicationTreeNode>>;
+
+  /**
+   * A map of addresses in the tree to their corresponding events.
+   */
+  #events: Map<string, NDKEvent>;
+
+  /**
+   * An ordered list of the addresses of the leaves of the tree.
+   */
+  #leaves: string[] = [];
+
+  /**
+   * The address of the last-visited node.  Used for iteration and progressive retrieval.
+   */
+  #bookmark?: string;
+
+  /**
+   * The NDK instance used to fetch events.
+   */
+  #ndk: NDK;
+
+  constructor(rootEvent: NDKEvent, ndk: NDK) {
+    const rootAddress = rootEvent.tagAddress();
+    this.#root = {
+      type: PublicationTreeNodeType.Root,
+      address: rootAddress,
+      children: [],
+    };
+
+    this.#nodes = new Map<string, Lazy<PublicationTreeNode>>();
+    this.#nodes.set(rootAddress, new Lazy<PublicationTreeNode>(() => Promise.resolve(this.#root)));
+
+    this.#events = new Map<string, NDKEvent>();
+    this.#events.set(rootAddress, rootEvent);
+
+    this.#ndk = ndk;
+  }
+
+  /**
+   * Adds an event to the publication tree.
+   * @param event The event to be added.
+   * @param parentEvent The parent event of the event to be added.
+   * @throws An error if the parent event is not in the tree.
+   * @description The parent event must already be in the tree. Use
+   * {@link PublicationTree.getEvent} to retrieve an event already in the tree.
+   */
+  async addEvent(event: NDKEvent, parentEvent: NDKEvent) {
+    const address = event.tagAddress();
+    const parentAddress = parentEvent.tagAddress();
+    const parentNode = await this.#nodes.get(parentAddress)?.value();
+
+    if (!parentNode) {
+      throw new Error(
+        `PublicationTree: Parent node with address ${parentAddress} not found.`
+      );
+    }
+
+    const node: PublicationTreeNode = {
+      type: await this.#getNodeType(event),
+      address,
+      parent: parentNode,
+      children: [],
+    };
+    const lazyNode = new Lazy<PublicationTreeNode>(() => Promise.resolve(node));
+    parentNode.children!.push(lazyNode);
+    this.#nodes.set(address, lazyNode);
+    this.#events.set(address, event);
+  }
+
+  /**
+   * Lazily adds an event to the publication tree by address if the full event is not already
+   * loaded into memory.
+   * @param address The address of the event to add.
+   * @param parentEvent The parent event of the event to add.
+   * @description The parent event must already be in the tree. Use
+   * {@link PublicationTree.getEvent} to retrieve an event already in the tree.
+   */
+  async addEventByAddress(address: string, parentEvent: NDKEvent) {
+    const parentAddress = parentEvent.tagAddress();
+    const parentNode = await this.#nodes.get(parentAddress)?.value();
+
+    if (!parentNode) {
+      throw new Error(
+        `PublicationTree: Parent node with address ${parentAddress} not found.`
+      );
+    }
+
+    await this.#addNode(address, parentNode);
+  }
+
+  /**
+   * Retrieves an event from the publication tree.
+   * @param address The address of the event to retrieve.
+   * @returns The event, or null if the event is not found.
+   */
+  async getEvent(address: string): Promise<NDKEvent | null> {
+    let event = this.#events.get(address) ?? null;
+    if (!event) {
+      event = await this.#depthFirstRetrieve(address);
+    }
+
+    return event;
+  }
+
+  /**
+   * Retrieves the addresses of the loaded children, if any, of the node with the given address.
+   * @param address The address of the parent node.
+   * @returns An array of addresses of any loaded child nodes.
+   */
+  async getChildAddresses(address: string): Promise<string[]> {
+    const node = await this.#nodes.get(address)?.value();
+    if (!node) {
+      throw new Error(`PublicationTree: Node with address ${address} not found.`);
+    }
+
+    return Promise.all(
+      node.children?.map(async child =>
+        (await child.value()).address
+      ) ?? []
+    );
+  }
+  /**
+   * Retrieves the events in the hierarchy of the event with the given address.
+   * @param address The address of the event for which to retrieve the hierarchy.
+   * @returns Returns an array of events in the addressed event's hierarchy, beginning with the
+   * root and ending with the addressed event.
+   */
+  async getHierarchy(address: string): Promise<NDKEvent[]> {
+    let node = await this.#nodes.get(address)?.value();
+    if (!node) {
+      throw new Error(`PublicationTree: Node with address ${address} not found.`);
+    }
+
+    const hierarchy: NDKEvent[] = [this.#events.get(address)!];
+    
+    while (node.parent) {
+      hierarchy.push(this.#events.get(node.parent.address)!);
+      node = node.parent;
+    }
+
+    return hierarchy.reverse();
+  }
+
+  /**
+   * Sets a start point for iteration over the leaves of the tree.
+   * @param address The address of the event to bookmark.
+   */
+  setBookmark(address: string) {
+    this.#bookmark = address;
+    this.#cursor.tryMoveTo(address);
+  }
+
+  // #region Iteration Cursor
+
+  #cursor = new class {
+    target: PublicationTreeNode | null | undefined;
+
+    #tree: PublicationTree;
+
+    constructor(tree: PublicationTree) {
+      this.#tree = tree;
+    }
+
+    async tryMoveTo(address?: string) {
+      if (!address) {
+        const startEvent = await this.#tree.#depthFirstRetrieve();
+        this.target = await this.#tree.#nodes.get(startEvent!.tagAddress())?.value();
+      } else {
+        this.target = await this.#tree.#nodes.get(address)?.value();
+      }
+
+      if (!this.target) {
+        return false;
+      }
+
+      return true;
+    }
+
+    async tryMoveToFirstChild(): Promise<boolean> {
+      if (!this.target) {
+        throw new Error("Cursor: Target node is null or undefined.");
+      }
+
+      if (this.target.type === PublicationTreeNodeType.Leaf) {
+        return false;
+      }
+      
+      this.target = (await this.target.children?.at(0)?.value())!;
+      return true;
+    }
+
+    async tryMoveToNextSibling(): Promise<boolean> {
+      if (!this.target) {
+        throw new Error("Cursor: Target node is null or undefined.");
+      }
+
+      const parent = this.target.parent;
+      const siblings = parent?.children;
+      if (!siblings) {
+        return false;
+      }
+
+      const currentIndex = await siblings.findIndexAsync(
+        async (sibling: Lazy<PublicationTreeNode>) => (await sibling.value()).address === this.target!.address
+      );
+
+      if (currentIndex === -1) {
+        return false;
+      }
+
+      const nextSibling = (await siblings.at(currentIndex + 1)?.value()) ?? null;
+      if (!nextSibling) {
+        return false;
+      }
+
+      this.target = nextSibling;
+      return true;
+    }
+
+    tryMoveToParent(): boolean {
+      if (!this.target) {
+        throw new Error("Cursor: Target node is null or undefined.");
+      }
+
+      const parent = this.target.parent;
+      if (!parent) {
+        return false;
+      }
+
+      this.target = parent;
+      return true;
+    }
+  }(this);
+
+  // #endregion
+
+  // #region Async Iterator Implementation
+
+  [Symbol.asyncIterator](): AsyncIterator<NDKEvent> {
+    return this;
+  }
+
+  async next(): Promise<IteratorResult<NDKEvent>> {
+    if (!this.#cursor.target) {
+      await this.#cursor.tryMoveTo(this.#bookmark);
+    }
+
+    do {
+      if (await this.#cursor.tryMoveToFirstChild()) {
+        continue;
+      }
+
+      if (await this.#cursor.tryMoveToNextSibling()) {
+        continue;
+      }
+
+      if (this.#cursor.tryMoveToParent()) {
+        continue;
+      }
+
+      if (this.#cursor.target?.type === PublicationTreeNodeType.Root) {
+        return { done: true, value: null };
+      }
+    } while (this.#cursor.target?.type !== PublicationTreeNodeType.Leaf);
+
+    const event = await this.getEvent(this.#cursor.target!.address);
+    return { done: false, value: event! };
+  }
+
+  // #endregion
+
+  // #region Private Methods
+
+  /**
+   * Traverses the publication tree in a depth-first manner to retrieve an event, filling in
+   * missing nodes during the traversal.
+   * @param address The address of the event to retrieve. If no address is provided, the function
+   * will return the first leaf in the tree.
+   * @returns The event, or null if the event is not found.
+   */
+  async #depthFirstRetrieve(address?: string): Promise<NDKEvent | null> {
+    if (address && this.#nodes.has(address)) {
+      return this.#events.get(address)!;
+    }
+
+    const stack: string[] = [this.#root.address];
+    let currentNode: PublicationTreeNode | null | undefined = this.#root;
+    let currentEvent: NDKEvent | null | undefined = this.#events.get(this.#root.address)!;
+    while (stack.length > 0) {
+      const currentAddress = stack.pop();
+      currentNode = await this.#nodes.get(currentAddress!)?.value();
+      if (!currentNode) {
+        throw new Error(`PublicationTree: Node with address ${currentAddress} not found.`);
+      }
+
+      currentEvent = this.#events.get(currentAddress!);
+      if (!currentEvent) {
+        throw new Error(`PublicationTree: Event with address ${currentAddress} not found.`);
+      }
+
+      // Stop immediately if the target of the search is found.
+      if (address != null && currentAddress === address) {
+        return currentEvent;
+      }
+
+      const currentChildAddresses = currentEvent.tags
+        .filter(tag => tag[0] === 'a')
+        .map(tag => tag[1]);
+
+      // If the current event has no children, it is a leaf.
+      if (currentChildAddresses.length === 0) {
+        // Return the first leaf if no address was provided.
+        if (address == null) {
+          return currentEvent!;
+        }
+
+        continue;
+      }
+
+      // Augment the tree with the children of the current event.
+      for (const childAddress of currentChildAddresses) {
+        if (this.#nodes.has(childAddress)) {
+          continue;
+        }
+
+        await this.#addNode(childAddress, currentNode!);
+      }
+
+      // Push the popped address's children onto the stack for the next iteration.
+      while (currentChildAddresses.length > 0) {
+        const nextAddress = currentChildAddresses.pop()!;
+        stack.push(nextAddress);
+      }
+    }
+
+    return null;
+  }
+
+  #addNode(address: string, parentNode: PublicationTreeNode) {
+    const lazyNode = new Lazy<PublicationTreeNode>(() => this.#resolveNode(address, parentNode));
+    parentNode.children!.push(lazyNode);
+    this.#nodes.set(address, lazyNode);
+  }
+
+  /**
+   * Resolves a node address into an event, and creates new nodes for its children.
+   * 
+   * This method is intended for use as a {@link Lazy} resolver.
+   * 
+   * @param address The address of the node to resolve.
+   * @param parentNode The parent node of the node to resolve.
+   * @returns The resolved node.
+   */
+  async #resolveNode(
+    address: string,
+    parentNode: PublicationTreeNode
+  ): Promise<PublicationTreeNode> {
+    const [kind, pubkey, dTag] = address.split(':');
+    const event = await this.#ndk.fetchEvent({
+      kinds: [parseInt(kind)],
+      authors: [pubkey],
+      '#d': [dTag],
+    });
+
+    if (!event) {
+      throw new Error(
+        `PublicationTree: Event with address ${address} not found.`
+      );
+    }
+
+    this.#events.set(address, event);
+
+    const childAddresses = event.tags.filter(tag => tag[0] === 'a').map(tag => tag[1]);
+    
+    const node: PublicationTreeNode = {
+      type: await this.#getNodeType(event),
+      address,
+      parent: parentNode,
+      children: [],
+    };
+
+    for (const address of childAddresses) {
+      this.addEventByAddress(address, event);
+    }
+
+    return node;
+  }
+
+  async #getNodeType(event: NDKEvent): Promise<PublicationTreeNodeType> {
+    if (event.tagAddress() === this.#root.address) {
+      return PublicationTreeNodeType.Root;
+    }
+
+    if (event.kind === 30040 && event.tags.some(tag => tag[0] === 'a')) {
+      return PublicationTreeNodeType.Branch;
+    }
+
+    return PublicationTreeNodeType.Leaf;
+  }
+
+  // #endregion
+}

src/lib/parser.ts

@@ -12,7 +12,7 @@ import type {
 } from 'asciidoctor';
 import he from 'he';
 import { writable, type Writable } from 'svelte/store';
-import { zettelKinds } from './consts';
+import { zettelKinds } from './consts.ts';
 
 interface IndexMetadata {
   authors?: string[];
@@ -66,6 +66,8 @@ export default class Pharos {
 
   private asciidoctor: Asciidoctor;
 
+  private pharosExtensions: Extensions.Registry;
+
   private ndk: NDK;
 
   private contextCounters: Map<string, number> = new Map<string, number>();
@@ -130,25 +132,26 @@ export default class Pharos {
 
   constructor(ndk: NDK) {
     this.asciidoctor = asciidoctor();
+    this.pharosExtensions = this.asciidoctor.Extensions.create();
 
     this.ndk = ndk;
 
     const pharos = this;
-    this.asciidoctor.Extensions.register(function () {
-      const registry = this;
-      registry.treeProcessor(function () {
-        const dsl = this;
-        dsl.process(function (document) {
-          const treeProcessor = this;
-          pharos.treeProcessor(treeProcessor, document);
-        });
-      })
+    this.pharosExtensions.treeProcessor(function () {
+      const dsl = this;
+      dsl.process(function (document) {
+        const treeProcessor = this;
+        pharos.treeProcessor(treeProcessor, document);
+      });
     });
   }
 
   parse(content: string, options?: ProcessorOptions | undefined): void {
     try {
-      this.html = this.asciidoctor.convert(content, options) as string | Document | undefined;
+      this.html = this.asciidoctor.convert(content, {
+        'extension_registry': this.pharosExtensions,
+        ...options,
+      }) as string | Document | undefined;
     } catch (error) {
       console.error(error);
       throw new Error('Failed to parse AsciiDoc document.');

src/lib/snippets/PublicationSnippets.svelte

@@ -0,0 +1,45 @@
+<script module lang='ts'>
+  import { P } from 'flowbite-svelte';
+
+  export { contentParagraph, sectionHeading };
+</script>
+
+{#snippet sectionHeading(title: string, depth: number)}
+  {#if depth === 0}
+    <h1 class='h-leather'>
+      {title}
+    </h1>
+  {:else if depth === 1}
+    <h2 class='h-leather'>
+      {title}
+    </h2>
+  {:else if depth === 2}
+    <h3 class='h-leather'>
+      {title}
+    </h3>
+  {:else if depth === 3}
+    <h4 class='h-leather'>
+      {title}
+    </h4>
+  {:else if depth === 4}
+    <h5 class='h-leather'>
+      {title}
+    </h5>
+  {:else}
+    <h6 class='h-leather'>
+      {title}
+    </h6>
+  {/if}
+{/snippet}
+
+{#snippet contentParagraph(content: string, publicationType: string, isSectionStart: boolean)}
+  {#if publicationType === 'novel'}
+    <P class='whitespace-normal' firstupper={isSectionStart}>
+      {@html content}
+    </P>
+  {:else}
+    <P class='whitespace-normal' firstupper={false}>
+      {@html content}
+    </P>
+  {/if}
+{/snippet}

src/lib/utils.ts

@@ -109,3 +109,38 @@ export function filterValidIndexEvents(events: Set<NDKEvent>): Set<NDKEvent> {
   console.debug(`Filtered index events: ${events.size} events remaining.`);
   return events;
 }
+
+/**
+ * Async version of Array.findIndex() that runs sequentially.
+ * Returns the index of the first element that satisfies the provided testing function.
+ * @param array The array to search
+ * @param predicate The async testing function
+ * @returns A promise that resolves to the index of the first matching element, or -1 if none found
+ */
+export async function findIndexAsync<T>(
+  array: T[],
+  predicate: (element: T, index: number, array: T[]) => Promise<boolean>
+): Promise<number> {
+  for (let i = 0; i < array.length; i++) {
+    if (await predicate(array[i], i, array)) {
+      return i;
+    }
+  }
+  return -1;
+}
+
+// Extend Array prototype with findIndexAsync
+declare global {
+  interface Array<T> {
+    findIndexAsync(
+      predicate: (element: T, index: number, array: T[]) => Promise<boolean>
+    ): Promise<number>;
+  }
+}
+
+Array.prototype.findIndexAsync = function<T>(
+  this: T[],
+  predicate: (element: T, index: number, array: T[]) => Promise<boolean>
+): Promise<number> {
+  return findIndexAsync(this, predicate);
+};

src/routes/publication/+page.ts

@@ -1,11 +1,11 @@
 import { error } from '@sveltejs/kit';
-import { NDKRelay, NDKRelaySet, type NDKEvent } from '@nostr-dev-kit/ndk';
+import type { NDKEvent } from '@nostr-dev-kit/ndk';
 import type { PageLoad } from './$types';
-import { get } from 'svelte/store';
-import { getActiveRelays, inboxRelays, ndkInstance } from '$lib/ndk';
-import { standardRelays } from '$lib/consts';
+import { getActiveRelays } from '$lib/ndk.ts';
+import { setContext } from 'svelte';
+import { PublicationTree } from '$lib/data_structures/publication_tree.ts';
 
-export const load: PageLoad = async ({ url, parent }) => {
+export const load: PageLoad = async ({ url, parent }: { url: URL; parent: () => Promise<any> }) => {
   const id = url.searchParams.get('id');
   const dTag = url.searchParams.get('d');
 
@@ -41,6 +41,8 @@ export const load: PageLoad = async ({ url, parent }) => {
   const publicationType = indexEvent?.getMatchingTags('type')[0]?.[1];
   const fetchPromise = parser.fetch(indexEvent);
 
+  setContext('publicationTree', new PublicationTree(indexEvent, ndk));
+
   return {
     waitable: fetchPromise,
     publicationType,

tsconfig.json

@@ -8,7 +8,8 @@
     "resolveJsonModule": true,
     "skipLibCheck": true,
     "sourceMap": true,
-    "strict": true
+    "strict": true,
+    "allowImportingTsExtensions": true
   }
   // Path aliases are handled by https://kit.svelte.dev/docs/configuration#alias
   //

vite.config.ts

@@ -3,6 +3,12 @@ import { defineConfig } from "vite";
 
 export default defineConfig({
   plugins: [sveltekit()],
+  resolve: {
+    alias: {
+      $lib: './src/lib',
+      $components: './src/components'
+    }
+  },
   test: {
     include: ['./tests/unit/**/*.unit-test.js']
   }