1 files changed, 63 insertions, 0 deletions
diff --git a/src/features/workspaces/logic/route.ts b/src/features/workspaces/logic/route.ts
new file mode 100644
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+++ b/src/features/workspaces/logic/route.ts
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+/**
+ * Pure routing logic for the workspaces feature — zero DOM, zero effects, zero Svelte.
+ *
+ * The app is URL-driven: the root path `/` is the workspaces HOME (lists all
+ * workspaces); a single path segment `/<id>` opens the workspace with that id
+ * (the slug). This module holds the pure mapping from a pathname to a `Route`,
+ * plus the slug-validation rules mirrored from the backend's `PUT /workspaces/:id`.
+ */
+
+/**
+ * The workspace slug regex (mirrors the backend's `PUT /workspaces/:id`
+ * validation): 1–40 chars, lowercase alphanumeric with internal hyphens only
+ * (no leading/trailing hyphen). `"default"` matches and is a valid (but
+ * non-deletable) id.
+ */
+export const WORKSPACE_SLUG_RE = /^[a-z0-9](?:[a-z0-9-]{0,38}[a-z0-9])?$/;
+
+/** A route derived from the URL path. */
+export type Route = { readonly kind: "home" } | { readonly kind: "workspace"; readonly id: string };
+
+/** The reserved id of the always-present fallback workspace. */
+export const DEFAULT_WORKSPACE_ID = "default";
+
+/**
+ * Parse a pathname into a `Route`. `/` (or empty) → home; a leading segment →
+ * the workspace with that id (URL-decoded, surrounding slashes trimmed). Deeper
+ * paths take their FIRST segment (nested routes are not used in v1). Pure:
+ * pathname in, route out. Does NOT validate the slug — an invalid id still
+ * produces a `workspace` route; the backend's ensure call rejects it (the FE
+ * surfaces the error).
+ */
+export function parsePath(pathname: string): Route {
+  const trimmed = pathname.replace(/^\/+|\/+$/g, "");
+  if (trimmed === "") return { kind: "home" };
+  const first = trimmed.split("/")[0] ?? "";
+  const id = safeDecode(first);
+  if (id === "") return { kind: "home" };
+  return { kind: "workspace", id };
+}
+
+/**
+ * Whether a slug is valid for a NEW workspace (the form the backend accepts).
+ * Used by the home view's "new workspace" input before navigating.
+ */
+export function isValidSlug(slug: string): boolean {
+  return WORKSPACE_SLUG_RE.test(slug);
+}
+
+/**
+ * Build the URL path for a workspace id. Used when navigating to / linking a
+ * workspace. Pure: id in, path string out.
+ */
+export function workspacePath(id: string): string {
+  return `/${id}`;
+}
+
+function safeDecode(segment: string): string {
+  try {
+    return decodeURIComponent(segment);
+  } catch {
+    return segment;
+  }
+}