Add DM attachment upload and preview flow

js/attachments/attachmentUtils.js

@@ -0,0 +1,162 @@
+import { devLogger } from "../utils/logger.js";
+
+export const ATTACHMENT_KIND = 15;
+
+const HEX_64_REGEX = /^[0-9a-f]{64}$/i;
+
+const TAG_NAMES = Object.freeze({
+  hash: "x",
+  url: "url",
+  name: "name",
+  type: "type",
+  size: "size",
+  key: "k",
+});
+
+function normalizeTagValue(value) {
+  if (typeof value !== "string") {
+    if (value === undefined || value === null) {
+      return "";
+    }
+    return String(value);
+  }
+  return value.trim();
+}
+
+function normalizeHash(value) {
+  const normalized = normalizeTagValue(value).toLowerCase();
+  if (!normalized) {
+    return "";
+  }
+  return HEX_64_REGEX.test(normalized) ? normalized : "";
+}
+
+function normalizeNumber(value) {
+  const numeric = Number(value);
+  if (!Number.isFinite(numeric) || numeric < 0) {
+    return null;
+  }
+  return Math.floor(numeric);
+}
+
+export function parseAttachmentTags(tags) {
+  if (!Array.isArray(tags)) {
+    return null;
+  }
+
+  const fields = {
+    x: "",
+    url: "",
+    name: "",
+    type: "",
+    size: null,
+    key: "",
+  };
+
+  tags.forEach((tag) => {
+    if (!Array.isArray(tag) || tag.length < 2) {
+      return;
+    }
+
+    const name = normalizeTagValue(tag[0]).toLowerCase();
+    const value = normalizeTagValue(tag[1]);
+
+    switch (name) {
+      case TAG_NAMES.hash:
+        fields.x = normalizeHash(value);
+        break;
+      case TAG_NAMES.url:
+        fields.url = value;
+        break;
+      case TAG_NAMES.name:
+        fields.name = value;
+        break;
+      case TAG_NAMES.type:
+        fields.type = value;
+        break;
+      case TAG_NAMES.size:
+        fields.size = normalizeNumber(value);
+        break;
+      case TAG_NAMES.key:
+        fields.key = value;
+        break;
+      default:
+        break;
+    }
+  });
+
+  if (!fields.x && !fields.url) {
+    return null;
+  }
+
+  return {
+    x: fields.x,
+    url: fields.url,
+    name: fields.name,
+    type: fields.type,
+    size: fields.size,
+    key: fields.key,
+    encrypted: Boolean(fields.key),
+  };
+}
+
+export function extractAttachmentsFromMessage(message) {
+  if (!message || typeof message !== "object") {
+    return [];
+  }
+
+  const event =
+    (message.message && typeof message.message === "object"
+      ? message.message
+      : null) ||
+    (message.event && typeof message.event === "object" ? message.event : null);
+
+  if (!event || Number(event.kind) !== ATTACHMENT_KIND) {
+    return [];
+  }
+
+  const attachment = parseAttachmentTags(event.tags);
+  if (!attachment) {
+    devLogger.warn("[attachments] Attachment event missing tags.");
+    return [];
+  }
+
+  return [attachment];
+}
+
+export function formatAttachmentSize(bytes) {
+  if (!Number.isFinite(bytes)) {
+    return "";
+  }
+
+  const units = ["B", "KB", "MB", "GB"];
+  let size = Math.max(bytes, 0);
+  let unitIndex = 0;
+
+  while (size >= 1024 && unitIndex < units.length - 1) {
+    size /= 1024;
+    unitIndex += 1;
+  }
+
+  const rounded = size >= 10 || unitIndex === 0 ? Math.round(size) : size.toFixed(1);
+  return `${rounded} ${units[unitIndex]}`;
+}
+
+export function describeAttachment(attachment) {
+  if (!attachment || typeof attachment !== "object") {
+    return "Attachment";
+  }
+
+  const name = typeof attachment.name === "string" ? attachment.name.trim() : "";
+  if (name) {
+    return `Attachment: ${name}`;
+  }
+
+  if (attachment.type) {
+    return `Attachment (${attachment.type})`;
+  }
+
+  return "Attachment";
+}
+
+export { TAG_NAMES as ATTACHMENT_TAG_NAMES };