/**
 * read-document.test.ts - the internal single-document read (`src/surface/read-document.ts`).
 *
 * This file was `read-model.test.ts` until `1.0.0-dev.8`, when the published `readUnion`
 * went. Three of its cases tested the BATCH POLICY rather than the read, and a batch no
 * longer exists, so each was re-pointed at the property that replaced it rather than
 * dropped:
 *
 *   - "a doc that fails to read is SKIPPED, not aborting the batch" -> a read that fails
 *     THROWS. With no other document to carry on for, swallowing a failure would leave
 *     "it failed" and "it is empty" as the same answer, which is the family of defect
 *     this package has closed repeatedly.
 *   - "returns [] for an empty doc SET (no query)" -> a document that holds nothing is
 *     read, answers, and returns `[]`. That is the surviving distinction: an empty ANSWER.
 *   - "the same subject IRI in two documents stays two entries, told apart by `graph`" ->
 *     two reads, each reporting its own document. Nothing can merge across documents any
 *     more, because nothing shares a call; `graph` went with the batch, since the caller
 *     names exactly one document and already holds its reference.
 *
 * One BEHAVIOUR CHANGE is pinned below rather than left to be discovered: a document the
 * holder has no capability for used to be dropped silently from the batch, and now makes
 * the read THROW - the refusal belongs to `docs.sparqlQuery`, which is the published door
 * this read goes through and which has always refused out loud.
 */

import { getCaps } from "../src/shared-wallet/bootstrap";
import { test, expect, mock, afterAll } from "bun:test";
import { readDocumentSubjects } from "../src/surface/read-document";
import type { Nuri } from "../src/model/types";
import { configure } from "../src/index";
import { configureStoreRegistry, setCurrentUser } from "../src/shared-wallet/bootstrap";
import { resetCaps } from "../src/shared-wallet/bootstrap";
import { resetOpenedRepos } from "../src/emulated-verifier/open-repo";
import { resetPublicStoreFetches } from "../src/emulated-verifier/public-store";

// The cap registry is process-wide, so each inject() starts from an empty one:
// once ANY cap exists the possession gate is in force for every reader, and a
// suite that never declares caps must not inherit another suite's.
afterAll(() => {
  resetCaps();
  resetOpenedRepos();
  resetPublicStoreFetches();
  setCurrentUser(null);
});

// A fake `ng` whose sparql_query answers the ANCHORED per-doc query (SELECT ?s ?p ?o
// WHERE { ?s ?p ?o }, anchor = the doc NURI) with ONLY that doc's triples. There is
// NO anchorless union scan: a document is read by its own anchor. Each entity subject
// IRI IS its own document NURI (writeEntity convention), so the fixture keys triples by
// the doc NURI and returns them for the matching anchor.
function fakeNgWith(triplesByDoc: Record<string, Array<[string, string]>>) {
  return {
    doc_create: mock(async () => "did:ng:o:new"),
    sparql_update: mock(async () => undefined),
    sparql_query: mock(async (_sid: string, _query: string, _base: unknown, anchor: unknown) => {
      // Every read is ANCHORED to one doc NURI — never anchorless.
      if (anchor === undefined) {
        throw new Error("read-document must NEVER run an anchorless (union) query");
      }
      const doc = anchor as string;
      const triples = triplesByDoc[doc];
      if (!triples) return { results: { bindings: [] } };
      const bindings = triples.map(([p, o]) => ({
        s: { value: doc },
        p: { value: p },
        o: { value: o },
      }));
      return { results: { bindings } };
    }),
  };
}

function inject(triplesByDoc: Record<string, Array<[string, string]>>) {
  const ng = fakeNgWith(triplesByDoc);
  resetCaps();
  resetOpenedRepos();
  resetPublicStoreFetches();
  setCurrentUser(null);
  configure({ ng: ng as any, useShape: (() => {}) as any });
  configureStoreRegistry({
    getSession: async () => ({ sessionId: "sid-rd", privateStoreId: "priv" }),
    normalizeId: (u: string) => u,
  });
  return ng;
}

const TYPE = "http://www.w3.org/1999/02/22-rdf-syntax-ns#type";
const FP = "http://festipod.org/";

test("reads the document with its OWN anchored query (never anchorless)", async () => {
  const ng = inject({
    "did:ng:o:a": [[TYPE, `${FP}Event`], [`${FP}title`, "A"]],
    "did:ng:o:b": [[TYPE, `${FP}Event`], [`${FP}title`, "B"]],
  });
  const a = await readDocumentSubjects("did:ng:o:a");
  const b = await readDocumentSubjects("did:ng:o:b");

  // One anchored query per read = 2 sparql_query calls, each anchored (c[3] set).
  expect(ng.sparql_query).toHaveBeenCalledTimes(2);
  const anchored = ng.sparql_query.mock.calls.filter((c: unknown[]) => c[3] !== undefined);
  expect(anchored.length).toBe(2);
  // The anchors are exactly the documents that were named.
  expect(anchored.map((c: unknown[]) => c[3])).toEqual(["did:ng:o:a", "did:ng:o:b"]);

  expect(a.map((s) => s.subject)).toEqual(["did:ng:o:a"]);
  expect(a[0]!.props[`${FP}title`]).toEqual(["A"]);
  expect(b[0]!.props[`${FP}title`]).toEqual(["B"]);
});

test("groups predicates per subject", async () => {
  inject({
    "did:ng:o:p": [
      [TYPE, `${FP}Participation`],
      [`${FP}event`, "did:ng:o:e"],
      [`${FP}user`, "urn:festipod:user:x"],
    ],
  });
  const s = (await readDocumentSubjects("did:ng:o:p"))[0]!;
  expect(s.subject).toBe("did:ng:o:p");
  expect(s.props[`${FP}event`]).toEqual(["did:ng:o:e"]);
  expect(s.props[`${FP}user`]).toEqual(["urn:festipod:user:x"]);
});

test("a document that holds nothing is READ, answers, and returns []", async () => {
  // The surviving half of the old "empty doc set" case, and the one that matters: an
  // empty ANSWER is not a failure, and the query really was issued to obtain it. A caller
  // deciding "absent versus unreadable" depends on exactly that difference.
  const ng = inject({});
  expect(await readDocumentSubjects("did:ng:o:empty")).toEqual([]);
  expect(ng.sparql_query).toHaveBeenCalledTimes(1);
});

test("a read that FAILS throws, rather than reading as an empty document", async () => {
  const ng = fakeNgWith({ "did:ng:o:ok": [[TYPE, `${FP}Event`], [`${FP}title`, "ok"]] });
  const orig = ng.sparql_query;
  // Make the anchored read throw for the bad doc only.
  ng.sparql_query = mock(async (sid: string, query: string, base: unknown, anchor: unknown) => {
    if (anchor === "did:ng:o:bad") throw new Error("RepoNotFound");
    return orig(sid, query, base, anchor);
  }) as any;
  resetCaps();
  resetOpenedRepos();
  resetPublicStoreFetches();
  setCurrentUser(null);
  configure({ ng: ng as any, useShape: (() => {}) as any });
  configureStoreRegistry({
    getSession: async () => ({ sessionId: "sid-rd", privateStoreId: "priv" }),
    normalizeId: (u: string) => u,
  });

  // The batch used to swallow this one and carry on with the good document. There is no
  // "carry on" left, so the failure reaches the caller as a failure — which is the ONLY
  // thing that keeps it distinguishable from a document that is genuinely empty.
  await expect(readDocumentSubjects("did:ng:o:bad")).rejects.toThrow(/RepoNotFound/);
  // The neighbour is unaffected: nothing is shared between two reads.
  expect((await readDocumentSubjects("did:ng:o:ok")).map((s) => s.subject)).toEqual([
    "did:ng:o:ok",
  ]);
});

// The possession gate: once ANY cap exists, a document whose cap is not in what the
// current holder holds is REFUSED — however well its NURI resolves. Before the first cap
// the gate is inert (no regression).
test("a document whose cap the holder does not hold is refused, out loud", async () => {
  inject({
    "did:ng:o:mine": [[TYPE, `${FP}Event`], [`${FP}title`, "mine"]],
    "did:ng:o:theirs": [[TYPE, `${FP}Event`], [`${FP}title`, "theirs"]],
  });
  const mine = "did:ng:o:mine" as Nuri;
  const theirs = "did:ng:o:theirs" as Nuri;

  // Inert: no cap issued yet → everything flows through.
  expect((await readDocumentSubjects(mine)).map((s) => s.subject)).toEqual([mine]);
  expect((await readDocumentSubjects(theirs)).map((s) => s.subject)).toEqual([theirs]);

  // One cap issued → possession is now the rule for every document. BEHAVIOUR CHANGE:
  // the batch dropped the unheld document silently and answered with the rest; a single
  // read has no rest, so `docs.sparqlQuery` refuses it the way it always has — loudly.
  setCurrentUser("alice");
  getCaps().mint(mine);
  expect((await readDocumentSubjects(mine)).map((s) => s.subject)).toEqual([mine]);
  await expect(readDocumentSubjects(theirs)).rejects.toThrow(/does not hold this document/i);

  // …and for every holder: bob holds nothing, so bob reads nothing.
  setCurrentUser("bob");
  await expect(readDocumentSubjects(mine)).rejects.toThrow(/does not hold this document/i);
});

test("a malformed reference is refused, loudly", async () => {
  // A non-reference is a caller mistake worth a loud error, never an empty read: swallowing
  // it is how a mistake becomes an absence nobody can explain. The list tolerance this
  // used to sit beside went with the batch — there is no list to carry a hole any more.
  inject({});
  await expect(readDocumentSubjects("not-a-nuri" as Nuri)).rejects.toThrow(
    /not a NextGraph reference/i,
  );
});

// ── several subjects inside one document ───────────────────────────────────
//
// The fixture above pins every row's subject to the doc NURI, which is what an
// application writing one entity per document produces — the recommended placement,
// and the only case it can exercise. A document may nevertheless carry SEVERAL
// subjects, and upstream that is the provided case, not an accident: the ORM carries
// `@id` and `@graph` as two distinct read-only properties and fabricates an `@id`
// when the writer leaves it empty, precisely so objects sharing a `@graph` stay
// distinguishable. This fixture lets the subject vary so that case can be tested.
function injectTriples(triplesByDoc: Record<string, Array<[string, string, string]>>) {
  const ng = {
    doc_create: mock(async () => "did:ng:o:new"),
    sparql_update: mock(async () => undefined),
    sparql_query: mock(async (_sid: string, _query: string, _base: unknown, anchor: unknown) => {
      if (anchor === undefined) {
        throw new Error("read-document must NEVER run an anchorless (union) query");
      }
      const triples = triplesByDoc[anchor as string];
      if (!triples) return { results: { bindings: [] } };
      return {
        results: {
          bindings: triples.map(([s, p, o]) => ({
            s: { value: s },
            p: { value: p },
            o: { value: o },
          })),
        },
      };
    }),
  };
  resetCaps();
  resetOpenedRepos();
  resetPublicStoreFetches();
  setCurrentUser(null);
  configure({ ng, useShape: () => undefined });
  configureStoreRegistry({
    getSession: async () => ({ sessionId: "sid-rd", privateStoreId: "priv" }),
    normalizeId: (u: string) => u,
  });
  return ng;
}

test("two subjects in ONE document come back as two entries, unmixed", async () => {
  // The document holds two entities under two IRIs of the consumer's choosing.
  injectTriples({
    "did:ng:o:d": [
      ["urn:app:alice", TYPE, `${FP}Person`],
      ["urn:app:alice", `${FP}title`, "A"],
      ["urn:app:bob", TYPE, `${FP}Person`],
      ["urn:app:bob", `${FP}title`, "B"],
    ],
  });

  const subjects = await readDocumentSubjects("did:ng:o:d");

  // Under the old per-document fold this was ONE entry subject'd `did:ng:o:d`,
  // whose `${FP}title` carried BOTH ["A","B"] — two entities conflated into one bag,
  // and both re-labelled with the document's own NURI.
  expect(subjects.length).toBe(2);
  expect(subjects.map((s) => s.subject).sort()).toEqual(["urn:app:alice", "urn:app:bob"]);

  const alice = subjects.find((s) => s.subject === "urn:app:alice")!;
  const bob = subjects.find((s) => s.subject === "urn:app:bob")!;
  expect(alice.props[`${FP}title`]).toEqual(["A"]);
  expect(bob.props[`${FP}title`]).toEqual(["B"]);
});

test("a subject written under an IRI of its own is NOT re-labelled with the doc NURI", async () => {
  injectTriples({
    "did:ng:o:d": [["urn:app:thing", `${FP}title`, "T"]],
  });
  const [only] = await readDocumentSubjects("did:ng:o:d");
  // The old fold reported `did:ng:o:d` here, a subject the document never carried.
  expect(only!.subject).toBe("urn:app:thing");
});

test("the SAME subject IRI in two documents is never merged - two reads, two answers", async () => {
  injectTriples({
    "did:ng:o:a": [["urn:app:shared", `${FP}title`, "in-a"]],
    "did:ng:o:b": [["urn:app:shared", `${FP}title`, "in-b"]],
  });
  const a = await readDocumentSubjects("did:ng:o:a");
  const b = await readDocumentSubjects("did:ng:o:b");
  // Two documents carrying one subject IRI are two objects. The batch had to say so with
  // a `graph` field on every entry; a read that names ONE document says it structurally,
  // because nothing of one read's answer can reach the other's.
  expect(a.map((s) => s.subject)).toEqual(["urn:app:shared"]);
  expect(b.map((s) => s.subject)).toEqual(["urn:app:shared"]);
  expect(a[0]!.props[`${FP}title`]).toEqual(["in-a"]);
  expect(b[0]!.props[`${FP}title`]).toEqual(["in-b"]);
});

test("machinery is dropped per subject, and the real subjects beside it survive", async () => {
  injectTriples({
    "did:ng:o:d": [
      ["urn:ng-eventually:shim:headerBranch", "urn:ng-eventually:p:inboxAddress", "did:ng:o:inbox"],
      ["urn:app:entity", `${FP}title`, "kept"],
    ],
  });
  const subjects = await readDocumentSubjects("did:ng:o:d");
  expect(subjects.map((s) => s.subject)).toEqual(["urn:app:entity"]);
  expect(subjects[0]!.props[`${FP}title`]).toEqual(["kept"]);
});

test("a document holding ONLY machinery yields no entry at all", async () => {
  injectTriples({
    "did:ng:o:d": [
      ["urn:ng-eventually:shim:headerBranch", "urn:ng-eventually:p:inboxAddress", "did:ng:o:inbox"],
    ],
  });
  expect(await readDocumentSubjects("did:ng:o:d")).toEqual([]);
});