fusion/packages/core/src/workflow-settings-resolver.ts

/**
 * Per-task EFFECTIVE workflow-settings resolution (U3, R3, KTD-3).
 *
 * Sibling of `workflow-ir-resolver.ts`. Composes three steps into the flat,
 * `Partial<ProjectSettings>`-shaped value map the engine reads at executor entry:
 *
 *   1. resolve the workflow IR (built-in or custom) → its `settings` declarations;
 *   2. read the raw stored `(workflowId, projectId)` value map;
 *   3. {@link resolveEffectiveSettingValues} → declaration default ?? stored value,
 *      dropping orphaned/invalid stored entries (KTD-6).
 *
 * The moved keys are all current `ProjectSettings` fields, so the returned map is a
 * structurally-compatible `Partial<ProjectSettings>` today. The engine MERGES this
 * over the project/global settings object so the ~20 flat `settings.<key>` read
 * sites keep their exact expressions (KTD-3).
 *
 * NEVER-THROW contract (mirrors the IR resolver): a missing/corrupt workflow
 * degrades to the built-in coding declarations; any store error degrades to an
 * empty stored map, so the result falls back to declaration defaults. The caller
 * always receives a usable map.
 *
 * IMPORTANT (parity): for built-in workflows with no stored values the effective
 * map carries the declaration defaults, which are byte-equal to the legacy
 * `DEFAULT_PROJECT_SETTINGS` literals — so merging it over project settings is a
 * no-op when nothing is customized. Keys whose declaration omits a default (the
 * per-phase model lanes) are ABSENT from the map (never `undefined`), so the merge
 * never clobbers a real project value with `undefined`.
 */

import {
  resolveWorkflowIrById,
  resolveWorkflowIrForTask,
  type WorkflowIrResolverStore,
} from "./workflow-ir-resolver.js";
import { resolveEffectiveSettingValues, findOrphanedSettingValues } from "./workflow-settings.js";
import { BUILTIN_WORKFLOW_SETTINGS } from "./builtin-workflow-settings.js";
import type { WorkflowSettingDefinition, WorkflowIr } from "./workflow-ir-types.js";

/**
 * The effective map PLUS the subset of keys whose value came from an EXPLICIT
 * STORED workflow value (not a declaration default). The engine entry merge uses
 * `storedKeys` to decide override-vs-fill semantics:
 *
 *  - a STORED key ALWAYS overrides the project/global base (the workflow tuned it);
 *  - a default-only key (in `effective` but NOT in `storedKeys`) only FILLS the
 *    base when the base lacks the key.
 *
 * This is what makes U3 behavior-identical pre-migration: a customized project
 * setting (still present in the base before the U4 hard-move) is NOT clobbered by a
 * declaration default; only a real stored workflow value overrides it. Post-
 * migration the base lacks the moved key, so the declaration default fills it.
 */
export interface EffectiveSettingsResult {
  effective: Record<string, unknown>;
  storedKeys: Set<string>;
}

/** Minimal store surface the effective-settings resolver needs (public APIs). */
export interface WorkflowSettingsResolverStore extends WorkflowIrResolverStore {
  /** Raw stored `(workflowId, projectId)` value map; `{}` when no row exists. */
  getWorkflowSettingValues(workflowId: string, projectId: string): Record<string, unknown>;
  /** The stable project id this store scopes `workflow_settings` rows by. A store
   *  instance is bound to one project, so the resolver derives the project key from
   *  the store rather than from the task (Task carries no projectId field). */
  getWorkflowSettingsProjectId(): string;
}

/** The declarations carried by a resolved IR, with the built-in catalog as the
 *  defensive belt for built-in graphs that predate the embedded `settings` (the
 *  linear `BUILTIN_WORKFLOWS` carry them now, but keep the belt cheap). */
function declarationsFromIr(
  ir: WorkflowIr,
  workflowId: string | undefined,
): WorkflowSettingDefinition[] | undefined {
  const declared = ir.version === "v2" ? ir.settings : undefined;
  if (declared && declared.length > 0) return declared;
  // Built-in workflows declare the full moved-key catalog (the migration parity
  // anchor); fall back to it only when the resolved IR didn't embed it.
  if (workflowId && workflowId.startsWith("builtin:")) return BUILTIN_WORKFLOW_SETTINGS;
  return declared;
}

/** Compose declarations + raw stored values → effective flat map + the set of keys
 *  whose value came from an explicit stored workflow value (never throws). */
function effectiveFrom(
  store: WorkflowSettingsResolverStore,
  ir: WorkflowIr,
  workflowId: string | undefined,
  projectId: string,
): EffectiveSettingsResult {
  const declarations = declarationsFromIr(ir, workflowId);
  let stored: Record<string, unknown> = {};
  if (workflowId) {
    try {
      stored = store.getWorkflowSettingValues(workflowId, projectId) ?? {};
    } catch {
      stored = {};
    }
  }
  const effective = resolveEffectiveSettingValues(declarations, stored);
  // A key is "stored" iff it appears in the effective map AND the stored row holds
  // a value for it that did NOT orphan (i.e. it was not dropped). Orphaned stored
  // entries fall to the declaration default, so they count as default-only.
  const orphanedIds = new Set(findOrphanedSettingValues(declarations, stored).map((o) => o.id));
  const storedKeys = new Set<string>();
  for (const id of Object.keys(effective)) {
    if (Object.prototype.hasOwnProperty.call(stored, id) && !orphanedIds.has(id)) {
      const raw = stored[id];
      if (raw !== null && raw !== undefined) storedKeys.add(id);
    }
  }
  return { effective, storedKeys };
}

/**
 * Resolve the effective workflow settings for an explicit `(workflowId,
 * projectId)`. Used by the migration/export/agent-tool paths that name a
 * workflow directly. Never throws.
 */
export async function resolveEffectiveSettingsById(
  store: WorkflowSettingsResolverStore,
  workflowId: string,
  projectId: string,
  irCache?: Map<string, WorkflowIr>,
): Promise<Record<string, unknown>> {
  const ir = await resolveWorkflowIrById(store, workflowId, irCache);
  return effectiveFrom(store, ir, workflowId, projectId).effective;
}

/** The minimal task identity the per-task resolver reads. Task carries no
 *  projectId field — the project key comes from the store. */
export interface EffectiveSettingsTaskRef {
  id: string;
}

/**
 * Resolve the effective workflow settings for a TASK (the engine's primary entry).
 * Reads the task's workflow selection, resolves its IR, and composes the effective
 * value map for `(resolvedWorkflowId, task.projectId)`.
 *
 * An absent/falsy selection degrades to `builtin:coding` (matching the IR
 * resolver), so a selection-less task reads the built-in declaration defaults —
 * byte-equal to legacy project-settings defaults. Never throws.
 */
export async function resolveEffectiveSettings(
  store: WorkflowSettingsResolverStore,
  task: EffectiveSettingsTaskRef,
  irCache?: Map<string, WorkflowIr>,
): Promise<Record<string, unknown>> {
  return (await resolveEffectiveSettingsDetailed(store, task, irCache)).effective;
}

/**
 * Like {@link resolveEffectiveSettings}, but also returns `storedKeys` (the keys
 * whose value came from an explicit stored workflow value vs. a declaration
 * default). The engine entry merge uses this to override the base only for stored
 * keys and fill-only for default-only keys. Never throws.
 */
export async function resolveEffectiveSettingsDetailed(
  store: WorkflowSettingsResolverStore,
  task: EffectiveSettingsTaskRef,
  irCache?: Map<string, WorkflowIr>,
): Promise<EffectiveSettingsResult> {
  let workflowId: string | undefined;
  try {
    workflowId = store.getTaskWorkflowSelection(task.id)?.workflowId;
  } catch {
    workflowId = undefined;
  }
  const effectiveWorkflowId = workflowId || "builtin:coding";
  const ir = await resolveWorkflowIrForTask(store, task.id, irCache);
  let projectId: string;
  try {
    projectId = store.getWorkflowSettingsProjectId();
  } catch {
    // Degrade to declaration defaults (empty stored map) on identity failure.
    // Keep the resolved workflowId so builtin graphs still pick up the catalog fallback.
    return effectiveFrom(store, ir, effectiveWorkflowId, "");
  }
  return effectiveFrom(store, ir, effectiveWorkflowId, projectId);
}