import { randomUUID } from "node:crypto";
import { and, eq } from "drizzle-orm";
import { afterAll, beforeAll, describe, expect, it } from "vitest";
import { agents, companies, createDb, heartbeatRuns, issueRelations, issues } from "@paperclipai/db";
import {
  getEmbeddedPostgresTestSupport,
  startEmbeddedPostgresTestDatabase,
} from "./helpers/embedded-postgres.js";
import { issueService } from "../services/issues.ts";
import { planIssueParentChange, resolveNewTaskParent } from "../services/issue-hierarchy.ts";
import { resolveIssueCreationSource } from "../services/issue-creation-source.ts";

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

describeEmbeddedPostgres("agent task hierarchy depth", () => {
  let tempDb: Awaited<ReturnType<typeof startEmbeddedPostgresTestDatabase>> | null = null;
  let db: ReturnType<typeof createDb>;

  beforeAll(async () => {
    tempDb = await startEmbeddedPostgresTestDatabase("paperclip-agent-task-depth-");
    db = createDb(tempDb.connectionString);
  });

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

  async function seedCompany() {
    const companyId = randomUUID();
    await db.insert(companies).values({
      id: companyId,
      name: "Paperclip",
      issuePrefix: `D${companyId.replace(/-/g, "").slice(0, 5).toUpperCase()}`,
      requireBoardApprovalForNewAgents: false,
    });
    const agentId = randomUUID();
    await db.insert(agents).values({
      id: agentId,
      companyId,
      name: "Coder",
      role: "engineer",
      status: "active",
      adapterType: "codex_local",
      adapterConfig: {},
      runtimeConfig: {},
      permissions: {},
    });
    return { companyId, agentId };
  }

  async function seedIssue(
    companyId: string,
    values: Partial<typeof issues.$inferInsert> = {},
  ) {
    const id = randomUUID();
    await db.insert(issues).values({
      id,
      companyId,
      title: `Task ${id.slice(0, 6)}`,
      status: "todo",
      priority: "medium",
      ...values,
    });
    return id;
  }

  async function seedTree(companyId: string) {
    const suffix = randomUUID().slice(0, 8);
    const rootIdentifier = `ROOT-${suffix}`;
    const childIdentifier = `CHILD-${suffix}`;
    const rootId = await seedIssue(companyId, { identifier: rootIdentifier });
    const childId = await seedIssue(companyId, { parentId: rootId, identifier: childIdentifier });
    return { rootId, childId, rootIdentifier, childIdentifier };
  }

  it("places an agent's child-of-a-child beside the requester and keeps it as the origin", async () => {
    const { companyId } = await seedCompany();
    const { rootId, childId, rootIdentifier, childIdentifier } = await seedTree(companyId);

    // expectedParentId: the route authorized the placed ancestor.
    const created = await issueService(db).create(companyId, {
      title: "Follow-up from the child",
      parentId: childId,
      expectedParentId: rootId,
    });

    expect(created.parentId).toBe(rootId);
    expect(created.originIssueId).toBe(childId);
    expect(created.privacyParentIssueId).toBe(childId);
    expect(created.parentAdjusted).toEqual({
      reason: "max_agent_depth",
      applied: true,
      requestedParent: { id: childId, identifier: childIdentifier },
      effectiveParent: { id: rootId, identifier: rootIdentifier },
    });
  });

  it("lets board users create grandchildren", async () => {
    const { companyId } = await seedCompany();
    const { childId } = await seedTree(companyId);

    const created = await issueService(db).create(companyId, {
      title: "Board grandchild",
      parentId: childId,
      parentDepthPolicy: "allow_nested",
    });

    expect(created.parentId).toBe(childId);
    expect(created.originIssueId).toBe(childId);
    expect(created.parentAdjusted).toBeUndefined();
  });

  it("creates direct children of a top-level task unchanged", async () => {
    const { companyId } = await seedCompany();
    const { rootId } = await seedTree(companyId);

    const created = await issueService(db).create(companyId, { title: "Second child", parentId: rootId });

    expect(created.parentId).toBe(rootId);
    expect(created.originIssueId).toBe(rootId);
    expect(created.parentAdjusted).toBeUndefined();
  });

  it("records the creating run's task as the origin of a top-level task", async () => {
    const { companyId, agentId } = await seedCompany();
    const sourceId = await seedIssue(companyId);
    const runId = randomUUID();
    await db.insert(heartbeatRuns).values({ id: runId, companyId, agentId, status: "running", issueId: sourceId });

    const created = await issueService(db).create(companyId, {
      title: "Standalone follow-up",
      parentId: null,
      createdByAgentId: agentId,
      actorRunId: runId,
    });

    expect(created.parentId).toBeNull();
    expect(created.originIssueId).toBe(sourceId);
    expect(created.originRunId).toBe(runId);
  });

  it("flattens legacy deep trees to their root", async () => {
    const { companyId } = await seedCompany();
    const { rootId, childId } = await seedTree(companyId);
    const grandchildId = await seedIssue(companyId, { parentId: childId });

    const created = await issueService(db).create(companyId, { title: "Under legacy grandchild", parentId: grandchildId, expectedParentId: rootId });

    expect(created.parentId).toBe(rootId);
    expect(created.originIssueId).toBe(grandchildId);
    expect(created.parentAdjusted?.requestedParent?.id).toBe(grandchildId);
  });

  it("blocks the requester, not the root, when a flattened child should block its parent", async () => {
    const { companyId } = await seedCompany();
    const { rootId, childId } = await seedTree(companyId);

    const { issue, parentBlockerAdded } = await issueService(db).createChild(childId, {
      title: "Blocking follow-up",
      blockParentUntilDone: true,
      expectedParentId: rootId,
    });

    expect(issue.parentId).toBe(rootId);
    expect(issue.originIssueId).toBe(childId);
    expect(issue.parentAdjusted?.reason).toBe("max_agent_depth");
    expect(parentBlockerAdded).toBe(true);
    const blockers = await db
      .select({ relatedIssueId: issueRelations.relatedIssueId })
      .from(issueRelations)
      .where(and(eq(issueRelations.issueId, issue.id), eq(issueRelations.type, "blocks")));
    expect(blockers.map((row) => row.relatedIssueId)).toEqual([childId]);
  });

  it("reuses a flattened child for the same idempotency key", async () => {
    const { companyId } = await seedCompany();
    const { childId } = await seedTree(companyId);
    const idempotencyKey = `flatten-${randomUUID()}`;

    const first = await issueService(db).createChild(childId, { title: "Once", idempotencyKey });
    const second = await issueService(db).createChild(childId, { title: "Once", idempotencyKey });

    expect(second.issue.id).toBe(first.issue.id);
  });

  it("places under the real root of a legacy tree deeper than 64 levels", async () => {
    const { companyId } = await seedCompany();
    const rootId = await seedIssue(companyId);
    let deepestId = rootId;
    for (let level = 1; level < 70; level += 1) deepestId = await seedIssue(companyId, { parentId: deepestId });

    const created = await issueService(db).create(companyId, { title: "From the 70th level", parentId: deepestId, expectedParentId: rootId });

    expect(created.parentId).toBe(rootId);
    expect(created.originIssueId).toBe(deepestId);
  });

  it("does not move a task above a low-trust boundary root", async () => {
    const { companyId } = await seedCompany();
    const rootId = await seedIssue(companyId);
    const boundaryId = randomUUID();
    await seedIssue(companyId, {
      id: boundaryId,
      parentId: rootId,
      executionPolicy: {
        authorizationPolicy: {
          trustBoundary: { mode: "low_trust_review", companyId, rootIssueId: boundaryId },
        },
      },
    });

    const placement = await resolveNewTaskParent(db, companyId, boundaryId, "flatten");

    expect(placement).toEqual({ effectiveParentId: boundaryId, adjustment: null });
  });

  it("falls back to top level when a legacy tree is rooted at a conversation", async () => {
    const { companyId, agentId } = await seedCompany();
    const conversationId = await seedIssue(companyId, { conversationAgentId: agentId, conversationUserId: "user-1", conversationState: "active", assigneeAgentId: agentId,
    });
    const legacyChildId = await seedIssue(companyId, { parentId: conversationId });

    const created = await issueService(db).create(companyId, { title: "From legacy chat child", parentId: legacyChildId });

    expect(created.parentId).toBeNull();
    expect(created.originIssueId).toBe(legacyChildId);
    expect(created.parentAdjusted).toMatchObject({ reason: "max_agent_depth", effectiveParent: null });
  });

  it("rejects a create whose locked placement differs from the authorized one", async () => {
    const { companyId } = await seedCompany();
    const { rootId, childId } = await seedTree(companyId);
    const otherRootId = await seedIssue(companyId);
    // The route authorized placement under rootId; the child then moved.
    await db.update(issues).set({ parentId: otherRootId }).where(eq(issues.id, childId));

    await expect(issueService(db).create(companyId, {
      title: "Stale placement",
      parentId: childId,
      expectedParentId: rootId,
    })).rejects.toMatchObject({ status: 409 });
  });

  it("dedupes recent titles per requester, not across siblings placed under the same root", async () => {
    const { companyId } = await seedCompany();
    const { rootId, childId } = await seedTree(companyId);
    const otherChildId = await seedIssue(companyId, { parentId: rootId });

    const first = await issueService(db).create(companyId, { title: "Write tests", parentId: childId, allowDuplicate: false });
    const second = await issueService(db).create(companyId, { title: "Write tests", parentId: otherChildId, allowDuplicate: false });
    const repeat = await issueService(db).create(companyId, { title: "Write tests", parentId: childId, allowDuplicate: false });

    expect(second.id).not.toBe(first.id);
    expect(second.originIssueId).toBe(otherChildId);
    expect(repeat.id).toBe(first.id);
  });

  it("ignores caller-supplied originIssueId", async () => {
    const { companyId } = await seedCompany();
    const { childId } = await seedTree(companyId);
    const forgedId = await seedIssue(companyId);

    const created = await issueService(db).create(companyId, {
      title: "Provenance is server-derived",
      parentId: childId,
      ...({ originIssueId: forgedId } as Record<string, unknown>),
    });

    expect(created.originIssueId).toBe(childId);
  });

  it("rejects a parent from another company on create and move", async () => {
    const { companyId } = await seedCompany();
    const { companyId: otherCompanyId } = await seedCompany();
    const foreignParentId = await seedIssue(otherCompanyId);

    await expect(issueService(db).create(companyId, { title: "Foreign parent", parentId: foreignParentId }))
      .rejects.toMatchObject({ status: 404 });
    await expect(issueService(db).create(companyId, {
      title: "Foreign parent, board", parentId: foreignParentId, parentDepthPolicy: "allow_nested",
    })).rejects.toMatchObject({ status: 404 });

    const movingId = await seedIssue(companyId);
    await expect(issueService(db).update(movingId, { parentId: foreignParentId, parentDepthPolicy: "allow_nested" }))
      .rejects.toMatchObject({ status: 404 });
  });

  it("originates from the creating run's task, not the named parent, in detail and lists", async () => {
    const { companyId, agentId } = await seedCompany();
    const { childId } = await seedTree(companyId);
    const runTaskId = await seedIssue(companyId);
    const runId = randomUUID();
    await db.insert(heartbeatRuns).values({ id: runId, companyId, agentId, status: "running", issueId: runTaskId });

    const created = await issueService(db).create(companyId, {
      title: "Named parent from another run", parentId: childId, createdByAgentId: agentId, actorRunId: runId,
    });
    // A run working on runTask filed this under childId: it originates from runTask.
    expect(created.originIssueId).toBe(runTaskId);
    expect(created.privacyParentIssueId).toBe(childId);

    const fromRunTask = await issueService(db).list(companyId, { createdFromIssueId: runTaskId });
    const fromChild = await issueService(db).list(companyId, { createdFromIssueId: childId });
    expect(fromRunTask.map((row) => row.id)).toContain(created.id);
    expect(fromChild.map((row) => row.id)).not.toContain(created.id);
    expect((await resolveIssueCreationSource(db, created))?.sourceIssue.id).toBe(runTaskId);
  });

  it("originates from a legacy run bound only by a task identifier", async () => {
    const { companyId, agentId } = await seedCompany();
    const { childId } = await seedTree(companyId);
    const identifier = `LEG-${randomUUID().slice(0, 6)}`;
    const runTaskId = await seedIssue(companyId, { identifier });
    const runId = randomUUID();
    await db.insert(heartbeatRuns).values({ id: runId, companyId, agentId, status: "running", contextSnapshot: { taskKey: identifier } });

    const created = await issueService(db).create(companyId, {
      title: "From a legacy-bound run", parentId: childId, createdByAgentId: agentId, actorRunId: runId,
    });

    expect(created.originIssueId).toBe(runTaskId);
  });

  it("makes unconfirmed placements standalone instead of writing under an unchecked ancestor", async () => {
    const { companyId } = await seedCompany();
    const { childId } = await seedTree(companyId);

    // Internal callers authorize only the parent they request.
    const created = await issueService(db).create(companyId, { title: "Internal follow-up", parentId: childId });
    expect(created.parentId).toBeNull();
    expect(created.privacyParentIssueId).toBe(childId);
    expect(created.originIssueId).toBe(childId);
    expect(created.parentAdjusted).toMatchObject({ reason: "max_agent_depth", applied: true, effectiveParent: null });

    const { issue } = await issueService(db).createChild(childId, { title: "Internal child helper" });
    expect(issue.parentId).toBeNull();

    const movingId = await seedIssue(companyId);
    const moved = await issueService(db).update(movingId, { parentId: childId, title: "Renamed anyway" });
    expect(moved?.parentId).toBeNull();
    expect(moved?.title).toBe("Renamed anyway");
    expect(moved?.parentAdjusted).toMatchObject({ reason: "max_agent_depth", applied: false, effectiveParent: null });

    // An already-parented task keeps its parent, and the notice names it.
    const otherRootId = await seedIssue(companyId, { identifier: `KEEP-${randomUUID().slice(0, 6)}` });
    const parentedId = await seedIssue(companyId, { parentId: otherRootId });
    const kept = await issueService(db).update(parentedId, { parentId: childId });
    expect(kept?.parentId).toBe(otherRootId);
    expect(kept?.parentAdjusted).toMatchObject({ applied: false, effectiveParent: { id: otherRootId } });
  });

  it("does not expose a private origin on a task its readers may see", async () => {
    const { companyId, agentId } = await seedCompany();
    const openParentId = await seedIssue(companyId);
    const privateTaskId = randomUUID();
    await seedIssue(companyId, { id: privateTaskId, visibility: "private", privacyRootIssueId: privateTaskId });
    const runId = randomUUID();
    await db.insert(heartbeatRuns).values({ id: runId, companyId, agentId, status: "running", issueId: privateTaskId });

    const created = await issueService(db).create(companyId, {
      title: "Open work filed from a private task", parentId: openParentId, createdByAgentId: agentId, actorRunId: runId,
    });

    expect(created.visibility).toBe("open");
    expect(created.originIssueId).toBeNull();
    // The audit link stays server-side through the run, checked for access on read.
    expect(created.originRunId).toBe(runId);
    expect((await resolveIssueCreationSource(db, created))?.sourceIssue.id).toBe(privateTaskId);
  });

  it("does not expose a hidden origin or a private sibling's id", async () => {
    const { companyId, agentId } = await seedCompany();
    const runOn = async (taskId: string) => {
      const runId = randomUUID();
      await db.insert(heartbeatRuns).values({ id: runId, companyId, agentId, status: "running", issueId: taskId });
      return runId;
    };

    const openParentId = await seedIssue(companyId);
    const hiddenTaskId = await seedIssue(companyId, { hiddenAt: new Date() });
    const fromHidden = await issueService(db).create(companyId, {
      title: "From a hidden task", parentId: openParentId, createdByAgentId: agentId, actorRunId: await runOn(hiddenTaskId),
    });
    expect(fromHidden.originIssueId).toBeNull();

    const rootId = randomUUID();
    await seedIssue(companyId, { id: rootId, visibility: "private", privacyRootIssueId: rootId });
    const siblingA = await seedIssue(companyId, { parentId: rootId, visibility: "private", privacyRootIssueId: rootId });
    const siblingB = await seedIssue(companyId, { parentId: rootId, visibility: "private", privacyRootIssueId: rootId });
    const fromSibling = await issueService(db).create(companyId, {
      title: "Filed under a private sibling", parentId: siblingB, createdByAgentId: agentId,
      actorRunId: await runOn(siblingA), expectedParentId: rootId,
    });
    expect(fromSibling.privacyParentIssueId).toBe(siblingB);
    expect(fromSibling.originIssueId).toBeNull();
    expect((await resolveIssueCreationSource(db, fromSibling))?.sourceIssue.id).toBe(siblingA);
  });

  describe("moves", () => {
    it("keeps the requested private parent as the privacy source of a placed move", async () => {
      const { companyId } = await seedCompany();
      const rootId = await seedIssue(companyId);
      const privateChildId = randomUUID();
      await seedIssue(companyId, { id: privateChildId, parentId: rootId, visibility: "private", privacyRootIssueId: privateChildId });
      const movingId = await seedIssue(companyId);

      const updated = await issueService(db).update(movingId, { parentId: privateChildId, expectedParentId: rootId });

      expect(updated?.parentId).toBe(rootId);
      expect(updated?.privacyParentIssueId).toBe(privateChildId);
      expect(updated?.visibility).toBe("private");
      expect(updated?.privacyRootIssueId).toBe(privateChildId);
    });

    it("rejects a move whose placement differs from the authorized one", async () => {
      const { companyId } = await seedCompany();
      const { childId } = await seedTree(companyId);
      const movingId = await seedIssue(companyId);

      await expect(issueService(db).update(movingId, { parentId: childId, expectedParentId: childId }))
        .rejects.toMatchObject({ status: 409 });
    });

    it("places an agent move into a child beside it", async () => {
      const { companyId } = await seedCompany();
      const { rootId, childId } = await seedTree(companyId);
      const movingId = await seedIssue(companyId);

      const updated = await issueService(db).update(movingId, { parentId: childId, expectedParentId: rootId });

      expect(updated?.parentId).toBe(rootId);
      expect(updated?.parentAdjusted).toMatchObject({ reason: "max_agent_depth", applied: true });
    });

    it("skips only the parent change when the moved task has children", async () => {
      const { companyId } = await seedCompany();
      const { rootId } = await seedTree(companyId);
      const movingId = await seedIssue(companyId);
      await seedIssue(companyId, { parentId: movingId });

      const updated = await issueService(db).update(movingId, { parentId: rootId, title: "Renamed" });

      expect(updated?.parentId).toBeNull();
      expect(updated?.title).toBe("Renamed");
      expect(updated?.parentAdjusted).toMatchObject({
        reason: "has_children",
        applied: false,
        requestedParent: { id: rootId },
        effectiveParent: null,
      });
    });

    it("lets board users move to any depth", async () => {
      const { companyId } = await seedCompany();
      const { childId } = await seedTree(companyId);
      const movingId = await seedIssue(companyId);
      await seedIssue(companyId, { parentId: movingId });

      const plan = await planIssueParentChange(
        db,
        { id: movingId, companyId, parentId: null },
        childId,
        "allow_nested",
      );
      expect(plan).toEqual({ parentId: childId, adjustment: null });

      const updated = await issueService(db).update(movingId, { parentId: childId, parentDepthPolicy: "allow_nested" });
      expect(updated?.parentId).toBe(childId);
      expect(updated?.parentAdjusted).toBeUndefined();
    });
  });

  it("resolves creation provenance from the recorded origin task", async () => {
    const { companyId } = await seedCompany();
    const { childId } = await seedTree(companyId);
    const created = await issueService(db).create(companyId, { title: "Flattened", parentId: childId });

    const source = await resolveIssueCreationSource(db, created);

    expect(source?.sourceIssue.id).toBe(childId);
    expect(source?.run).toBeNull();
  });
});