Add Nextcloud recipe display and controller

lib/nextcloud-public-share.js

@@ -0,0 +1,105 @@
+const { XMLParser } = require("fast-xml-parser");
+
+class NextcloudPublicShare {
+  constructor({ shareUrl, password = "", fetchImpl = global.fetch }) {
+    if (!shareUrl) throw new Error("Nextcloud Cookbook share URL is not configured");
+    if (typeof fetchImpl !== "function") throw new Error("A fetch implementation is required");
+
+    const parsed = new URL(shareUrl);
+    const tokenMatch = parsed.pathname.match(/\/s\/([^/]+)/);
+    if (!tokenMatch) throw new Error("Nextcloud public share URL must contain /s/<token>");
+
+    this.origin = parsed.origin;
+    this.token = decodeURIComponent(tokenMatch[1]);
+    this.password = password;
+    this.fetch = fetchImpl;
+    this.webdavUrl = new URL(`/public.php/dav/files/${encodeURIComponent(this.token)}/`, this.origin);
+    this.parser = new XMLParser({ ignoreAttributes: false, removeNSPrefix: true });
+  }
+
+  get headers() {
+    if (!this.password) return {};
+    return { Authorization: `Basic ${Buffer.from(`anonymous:${this.password}`).toString("base64")}` };
+  }
+
+  async listRecipes() {
+    const response = await this.fetch(this.webdavUrl, {
+      method: "PROPFIND",
+      headers: {
+        ...this.headers,
+        Depth: "infinity",
+        "X-Requested-With": "XMLHttpRequest",
+        "Content-Type": "application/xml; charset=utf-8"
+      },
+      body: "<?xml version=\"1.0\"?><d:propfind xmlns:d=\"DAV:\"><d:prop><d:resourcetype/></d:prop></d:propfind>"
+    });
+    if (!response.ok && response.status !== 207) {
+      throw new Error(`Nextcloud recipe listing failed with HTTP ${response.status}`);
+    }
+
+    const parsed = this.parser.parse(await response.text());
+    const responses = this.asArray(parsed.multistatus?.response);
+    const recipePaths = responses
+      .map((entry) => decodeURIComponent(entry.href || ""))
+      .filter((href) => href.toLowerCase().endsWith("/recipe.json"));
+
+    const recipes = await this.mapWithConcurrency(recipePaths, 6, async (path) => {
+      const recipe = await this.fetchJson(path);
+      return {
+        id: Buffer.from(path).toString("base64url"),
+        path,
+        name: recipe.name || this.folderName(path),
+        description: recipe.description || ""
+      };
+    });
+    return recipes.sort((left, right) => left.name.localeCompare(right.name));
+  }
+
+  async getRecipe(id) {
+    let path;
+    try {
+      path = Buffer.from(id, "base64url").toString("utf8");
+    } catch {
+      throw new Error("Invalid recipe identifier");
+    }
+    if (!path.startsWith(this.webdavUrl.pathname) || !path.toLowerCase().endsWith("/recipe.json")) {
+      throw new Error("Invalid recipe identifier");
+    }
+    return this.fetchJson(path);
+  }
+
+  async fetchJson(path) {
+    const response = await this.fetch(new URL(path, this.origin), {
+      headers: this.headers
+    });
+    if (!response.ok) {
+      throw new Error(`Nextcloud recipe fetch failed with HTTP ${response.status}`);
+    }
+    return response.json();
+  }
+
+  folderName(path) {
+    const parts = path.split("/").filter(Boolean);
+    return parts.length > 1 ? parts.at(-2) : "Untitled recipe";
+  }
+
+  asArray(value) {
+    if (!value) return [];
+    return Array.isArray(value) ? value : [value];
+  }
+
+  async mapWithConcurrency(items, limit, mapper) {
+    const results = new Array(items.length);
+    let next = 0;
+    const workers = Array.from({ length: Math.min(limit, items.length) }, async () => {
+      while (next < items.length) {
+        const index = next++;
+        results[index] = await mapper(items[index]);
+      }
+    });
+    await Promise.all(workers);
+    return results;
+  }
+}
+
+module.exports = NextcloudPublicShare;