init

lib/paths.js

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+/**
+ * Where this plugin keeps things on disk.
+ *
+ * Everything lives under `$DSH_HOME`, never inside the workspace. That is the
+ * whole point of the plugin's economics: the index holds a vector per code
+ * chunk, which for a 300k-line repository is tens of megabytes — several times
+ * the size of the source it describes. A multi-megabyte binary file appearing
+ * in a repository the user might commit, or that a `git status` might surface
+ * mid-task, is a worse outcome than the tokens it saves.
+ *
+ * The index is also disposable by construction. It is keyed by content hash, so
+ * deleting it costs one re-embed and nothing else — which is what makes it safe
+ * to treat as a cache rather than a document.
+ */
+
+import { createHash } from 'node:crypto'
+import { homedir } from 'node:os'
+import { basename, join, resolve } from 'node:path'
+
+/** Plugin name. Also the `$DSH_HOME/<name>` directory. */
+export const PLUGIN_NAME = 'dsh-recall'
+
+/** The dsh home directory: `$DSH_HOME`, else `~/.dsh`. */
+export function resolveDshHome(env = process.env) {
+  const configured = typeof env.DSH_HOME === 'string' ? env.DSH_HOME.trim() : ''
+  return configured === '' ? join(homedir(), '.dsh') : resolve(configured)
+}
+
+/**
+ * A stable, filesystem-safe key for one workspace.
+ *
+ * The basename is for a human reading the directory listing; the hash is what
+ * actually identifies it, so two checkouts both named `app` cannot collide and
+ * one checkout moved between parents does not silently inherit the other's
+ * index.
+ */
+export function workspaceKey(cwd) {
+  const absolute = resolve(cwd)
+  const name =
+    basename(absolute)
+      .replace(/[^A-Za-z0-9._-]+/g, '-')
+      .replace(/^[-.]+|-+$/g, '') || 'workspace'
+  const hash = createHash('sha256').update(absolute).digest('hex').slice(0, 8)
+  return `${name}-${hash}`
+}
+
+/** Root of this plugin's own data, independent of any workspace. */
+export function pluginDataDir(dshHome) {
+  return join(dshHome, PLUGIN_NAME)
+}
+
+/** Per-workspace state directory. */
+export function workspaceStateDir(dshHome, cwd) {
+  return join(pluginDataDir(dshHome), 'workspaces', workspaceKey(cwd))
+}
+
+/** The SQLite index for one workspace. */
+/**
+ * The SQLite index for one workspace, optionally narrowed to one focus.
+ *
+ * The workspace-wide index deliberately keeps its original path. Focus is
+ * additive: a deployment that never sets one must find the index it already
+ * built, not silently re-embed the repository into a new file.
+ *
+ * @param {string} dshHome harness home
+ * @param {string} cwd workspace root
+ * @param {string} [focus] focus key, `.` for the workspace itself
+ */
+export function indexFile(dshHome, cwd, focus = '.') {
+  const base = workspaceStateDir(dshHome, cwd)
+  return focus === '.' ? join(base, 'index.sqlite') : join(base, 'focus', focus, 'index.sqlite')
+}