import { randomUUID } from "node:crypto";
import { eq } from "drizzle-orm";
import { afterAll, afterEach, beforeAll, describe, expect, it } from "vitest";
import {
  companies,
  createDb,
  documentAnnotationAnchorSnapshots,
  documentAnnotationComments,
  documentAnnotationThreads,
  documentRevisions,
  documents,
  issueDocuments,
  issues,
} from "@paperclipai/db";
import {
  getEmbeddedPostgresTestSupport,
  startEmbeddedPostgresTestDatabase,
} from "./helpers/embedded-postgres.js";
import { documentAnnotationService } from "../services/document-annotations.js";
import { documentService } from "../services/documents.js";

const embeddedPostgresSupport = await getEmbeddedPostgresTestSupport();
const describeEmbeddedPostgres = embeddedPostgresSupport.supported ? describe : describe.skip;

if (!embeddedPostgresSupport.supported) {
  console.warn(
    `Skipping embedded Postgres document annotation service tests on this host: ${embeddedPostgresSupport.reason ?? "unsupported environment"}`,
  );
}

function deferred<T>() {
  let resolve!: (value: T | PromiseLike<T>) => void;
  let reject!: (reason?: unknown) => void;
  const promise = new Promise<T>((promiseResolve, promiseReject) => {
    resolve = promiseResolve;
    reject = promiseReject;
  });
  return { promise, resolve, reject };
}

describeEmbeddedPostgres("documentAnnotationService", () => {
  let db!: ReturnType<typeof createDb>;
  let annotations!: ReturnType<typeof documentAnnotationService>;
  let docs!: ReturnType<typeof documentService>;
  let tempDb: Awaited<ReturnType<typeof startEmbeddedPostgresTestDatabase>> | null = null;

  beforeAll(async () => {
    tempDb = await startEmbeddedPostgresTestDatabase("paperclip-document-annotations-");
    db = createDb(tempDb.connectionString);
    annotations = documentAnnotationService(db);
    docs = documentService(db);
  }, 20_000);

  afterEach(async () => {
    await db.delete(documentAnnotationAnchorSnapshots);
    await db.delete(documentAnnotationComments);
    await db.delete(documentAnnotationThreads);
    await db.delete(documentRevisions);
    await db.delete(issueDocuments);
    await db.delete(documents);
    await db.delete(issues);
    await db.delete(companies);
  });

  afterAll(async () => {
    await tempDb?.cleanup();
  });

  async function createIssueWithDocument() {
    const companyId = randomUUID();
    const issueId = randomUUID();

    await db.insert(companies).values({
      id: companyId,
      name: "Paperclip",
      issuePrefix: `T${companyId.replace(/-/g, "").slice(0, 6).toUpperCase()}`,
      requireBoardApprovalForNewAgents: false,
    });

    await db.insert(issues).values({
      id: issueId,
      companyId,
      identifier: "PAP-9442",
      title: "Annotation race",
      description: "Validate annotation revision guards",
      status: "in_progress",
      priority: "high",
    });

    const created = await docs.upsertIssueDocument({
      issueId,
      key: "plan",
      title: "Plan",
      format: "markdown",
      body: "Alpha selected text omega",
    });

    return { companyId, issueId, document: created.document };
  }

  it("fails closed when a concurrent document update wins before annotation thread creation commits", async () => {
    const { companyId, issueId, document } = await createIssueWithDocument();
    const concurrentUpdateCanCommit = deferred<void>();
    const concurrentUpdateHasWritten = deferred<void>();

    const concurrentUpdate = db.transaction(async (tx) => {
      const now = new Date();
      const [revision] = await tx
        .insert(documentRevisions)
        .values({
          companyId,
          documentId: document.id,
          revisionNumber: document.latestRevisionNumber + 1,
          title: "Plan",
          format: "markdown",
          body: "Alpha changed text omega",
          changeSummary: "Concurrent edit",
          createdAt: now,
        })
        .returning();

      await tx
        .update(documents)
        .set({
          latestBody: "Alpha changed text omega",
          latestRevisionId: revision.id,
          latestRevisionNumber: document.latestRevisionNumber + 1,
          updatedAt: now,
        })
        .where(eq(documents.id, document.id));

      concurrentUpdateHasWritten.resolve();
      await concurrentUpdateCanCommit.promise;
    });

    await concurrentUpdateHasWritten.promise;

    let annotationSettled = false;
    const annotationResult = annotations
      .createThread(
        issueId,
        "plan",
        {
          baseRevisionId: document.latestRevisionId!,
          baseRevisionNumber: document.latestRevisionNumber,
          selector: {
            quote: { exact: "selected text", prefix: "Alpha ", suffix: " omega" },
            position: { normalizedStart: 6, normalizedEnd: 19, markdownStart: 6, markdownEnd: 19 },
          },
          body: "Please review this text",
        },
        { actorType: "user", actorId: "board-user", userId: "board-user" },
      )
      .then(
        () => ({ status: "fulfilled" as const }),
        (error: unknown) => ({ status: "rejected" as const, error }),
      )
      .finally(() => {
        annotationSettled = true;
      });

    await new Promise((resolve) => setTimeout(resolve, 50));
    expect(annotationSettled).toBe(false);

    concurrentUpdateCanCommit.resolve();
    await concurrentUpdate;

    const result = await annotationResult;
    expect(result.status).toBe("rejected");
    if (result.status === "rejected") {
      expect(result.error).toMatchObject({
        status: 409,
        message: "Annotation anchor requires the current document revision",
        details: {
          currentRevisionNumber: 2,
        },
      });
    }

    const threads = await db.select().from(documentAnnotationThreads);
    expect(threads).toHaveLength(0);
  });
});