// #208 §7 — the declared-@unmanaged name set.
//
// An @unmanaged DB object is managed elsewhere (Flyway / a hand-migration owns its
// DDL). `meta migrate` must neither create, drop, nor drift-check it. It is already
// absent from the EXPECTED side (buildExpectedSchema Pass 1 skips an @unmanaged table;
// buildProjectionViews skips an @unmanaged view), so no create is proposed. This set is
// the ACT-side half: threaded into `diff`, it excludes these names from the introspected
// ACTUAL side so a declared-external object produces SILENCE, not a policy-gated drop.

import {
  isMetaSource,
  resolveTableSchema,
  TYPE_OBJECT,
  type MetaData,
} from "@metaobjectsdev/metadata";
import { qualifiedDbName } from "./qualified-name.js";

/**
 * The qualified physical names (`schema.name`, schema defaulting to Postgres `public`)
 * of every DB object declared `@unmanaged`. The format matches `tableIdentity` /
 * `viewIdentity` in the diff, so one set silences both drop-table and drop-view.
 *
 * Walks each object's OWN sources — the SAME own-source basis buildExpectedSchema Pass 1
 * uses to skip an `@unmanaged` table's descriptor, so the two halves of the diff agree
 * (an object skipped from `expected` is also excluded from `actual`): no split-brain
 * where a table is not created yet is still proposed for drop. `@unmanaged` is
 * per-source (ADR-0007 — physical concerns live on the source child), so a write-through
 * entity can mark only its read-view source `@unmanaged` while its table stays managed.
 * Own-source iteration also keeps `source.physicalName`'s owner-fallback resolving
 * against the declaring object rather than an `extends` super.
 */
export function collectUnmanagedNames(root: MetaData): string[] {
  const out: string[] = [];
  for (const obj of root.children()) {
    if (obj.type !== TYPE_OBJECT) continue;
    for (const src of obj.ownChildren()) {
      // isMetaSource, not `instanceof`: a split @metaobjectsdev/metadata tree would
      // make the class check false and silently un-silence a declared-@unmanaged
      // object, turning it back into a proposed drop.
      if (!isMetaSource(src) || !src.isUnmanaged) continue;
      out.push(qualifiedDbName({ name: src.physicalName, schema: resolveTableSchema(obj) }));
    }
  }
  return out;
}