refactor(#276): Phase 4 — parameter, export, document, saved-query, schema-graph, preferences services

CHANGELOG.md

@@ -10,6 +10,23 @@ auto-generated per-PR notes; this file is the curated, human-readable history.
 ## [Unreleased]
 
 ### Changed
+- **Phase 4 of the app.ts → services refactor complete** (#276): five more
+  focused modules under `src/application/`, all constructible without
+  `App`/`AppState`/DOM, behavior byte-identical. `WorkbenchParameterSession`
+  (`app.params`) owns the `{name:Type}` prepare/gate/hardening/recents
+  policy (the var strip stays a DOM view calling it); `ExportService`
+  (`app.exports`) owns direct + script export behind an injectable
+  `ExportSink`, consolidating the last duplicated cancellation-state copies
+  (its 40 test scenarios moved to an in-memory-sink spec);
+  `QueryDocumentSession` (`app.queryDoc`) owns the Spec evaluation/document
+  lifecycle and `SavedQueryService` (`app.saved`) the create/commit/history/
+  share persistence (typed results; the shell keeps the exact messages and
+  post-commit repaint cascade); `SchemaGraphSession` (`app.graph`) owns the
+  lineage operation lifecycle with its stale-request guards, the abort state
+  now session-private; `AppPreferences` (`app.prefs`) is the typed
+  preference-persistence surface (`save` + `toggleTheme` — deliberately no
+  speculative per-key setters). `app.ts` is down to 1,761 lines of shell
+  wiring from the original 2,964.
 - **Server metadata and reference lifecycle extracted into
   `SchemaCatalogService`** (#276 Phase 4A). Version probe, schema tree
   loading, lazy column loading, SQL reference/completions assembly, and the

src/application/app-preferences.ts

@@ -0,0 +1,77 @@
+// #276 Phase 4D's AppPreferences — the true browser-preference keys (as
+// opposed to the domain records — saved queries, history, query variables —
+// which keep their own dedicated `save*` methods on `App`, untouched here),
+// extracted from app.ts's `savePref`/`toggleTheme` (issue #276 §10).
+// Constructible without App/AppState/DOM. No imports from `src/ui/**` or
+// `src/editor/**` (a pretest check enforces this).
+//
+// Narrow scope (plan review): this service owns ONLY the persist half of
+// each preference. Every write site except `toggleTheme` already mutates its
+// own state field itself (splitters.ts sets `ctx.state.sidebarPx` before
+// calling `ctx.save(...)`; dashboard.ts sets `state.dashLayout`/`dashCols`
+// before `app.savePref(...)`; app.ts's `setResultRowLimit` sets
+// `state.resultRowLimit` first) — so `save(name, value)` is a pure typed
+// persist call, no state slice needed. `toggleTheme` is the one exception
+// (issue ruling): the state flip AND the persist happen together here: the
+// DOM half (the `data-theme` attribute + header icon swap) stays in app.ts's
+// own `toggleTheme`, which composes this service's `toggleTheme()` with that
+// DOM update. `createState` (state.ts) still owns every key's READ/seed at
+// startup — this service is write-only, never called during bootstrap.
+
+import type { SaveStr } from '../state.js';
+import { KEYS } from '../state.js';
+
+/** The true-preference subset of state.ts's own `KEYS` map — every OTHER key
+ *  there (saved/history/libraryName/varValues/filterActive/filterCurated/
+ *  varRecent/varRecentDisabled) is a domain record with its own dedicated
+ *  `save*` method on `App` (`saveJSON`/`saveVarValues`/`saveFilterActive`/…),
+ *  untouched by this service. */
+export type PreferenceKey =
+  | 'theme' | 'sidebarPx' | 'editorPct' | 'sideSplitPct' | 'cellDrawerPx'
+  | 'sidePanel' | 'resultRowLimit' | 'dashLayout' | 'dashCols';
+
+/** The one state field this service reads/writes (`toggleTheme` only) — a
+ *  plain settable property, not a signal (matches `AppState.theme`). */
+export interface AppPreferencesStateSlice {
+  theme: string;
+}
+
+export interface AppPreferencesDeps {
+  saveStr: SaveStr;
+  state: AppPreferencesStateSlice;
+}
+
+export interface AppPreferences {
+  /** Generic persist-only setter — the exact `(name, value)` shape app.ts's
+   *  public `savePref` has always exposed (dashboard.ts/saved-history.ts/
+   *  splitters.ts call it through that unchanged delegate). This IS the
+   *  service's write API: per-key typed setters were considered and dropped
+   *  (review) — every real call site already holds a validated
+   *  `{name, value}` pair, so a per-key surface would ship with zero
+   *  callers (CLAUDE.md rule 5: no speculative primitives). */
+  save(name: PreferenceKey, value: unknown): void;
+  /** Flips `state.theme` light↔dark AND persists it in one call (issue
+   *  ruling — the one preference whose state mutation moves here, not just
+   *  its persist half); returns the new value so the DOM-half caller
+   *  (app.ts's own `toggleTheme`) doesn't need to re-read `state.theme`. */
+  toggleTheme(): string;
+}
+
+/** Build an `AppPreferences` bound to `deps`. Trivial constructor — no
+ *  validation, no defaulting; the caller supplies every field of `deps`
+ *  exactly as it wants it used. */
+export function createAppPreferences(deps: AppPreferencesDeps): AppPreferences {
+  const { state } = deps;
+
+  function save(name: PreferenceKey, value: unknown): void {
+    deps.saveStr(KEYS[name], String(value));
+  }
+
+  function toggleTheme(): string {
+    state.theme = state.theme === 'dark' ? 'light' : 'dark';
+    save('theme', state.theme);
+    return state.theme;
+  }
+
+  return { save, toggleTheme };
+}