import { beforeEach, describe, expect, it, vi } from "vitest";
import type { Mock } from "vitest";
import type { Session } from "next-auth";
import {
  createLicense,
  listLicenses,
  validateCreateLicenseInput,
} from "@/lib/licenses";
import { prisma } from "@/lib/prisma";

// Note: this file has two layers of coverage, mirroring tests/assets.test.ts:
// - lib-level tests below exercise src/lib/licenses.ts directly (validation,
//   seatsUsed always 0, list ordering).
// - route-level tests (further down) exercise src/app/api/licenses/route.ts
//   over HTTP, including the auth() gate — mirrors tests/assets.test.ts's
//   @/auth mocking pattern.
vi.mock("@/auth", () => ({ auth: vi.fn() }));

import { GET, POST } from "@/app/api/licenses/route";
import { auth } from "@/auth";

const mockedAuth = auth as unknown as Mock<() => Promise<Session | null>>;

const testSession: Session = {
  user: { id: "test-user-id" },
  expires: new Date(Date.now() + 60 * 60 * 1000).toISOString(),
};

function postRequest(body: unknown): Request {
  return new Request("http://localhost/api/licenses", {
    method: "POST",
    headers: { "content-type": "application/json" },
    body: JSON.stringify(body),
  });
}

// License.vendorId is a real FK to Vendor (see schema.prisma /
// src/lib/licenses.ts) — tests that need a valid vendorId create a real
// Vendor row first and use its id, rather than an arbitrary string. Mirrors
// tests/requests.test.ts's createTestEmployee() helper.
function createTestVendor(overrides: { name?: string } = {}) {
  return prisma.vendor.create({
    data: {
      name: overrides.name ?? "Test Vendor",
      contactEmail: "sales@testvendor.example",
      contactPhone: "0281234567",
      address: "123 Test Street",
    },
  });
}

beforeEach(async () => {
  // Each test starts from empty tables so listing/order assertions are
  // deterministic. licenses must be cleared before vendors since
  // licenses.vendor_id has an FK (ON DELETE RESTRICT) to vendors.
  await prisma.license.deleteMany();
  await prisma.vendor.deleteMany();
  // Default to a logged-in session — the lib-level tests below don't go
  // through the route at all (so this is a no-op for them), and the
  // route-level tests exercise business logic, not auth gating (that's
  // covered by the "auth gating" describe block further down).
  mockedAuth.mockResolvedValue(testSession);
});

describe("validateCreateLicenseInput", () => {
  it("accepts valid input with an expiryDate", () => {
    const result = validateCreateLicenseInput({
      name: "Adobe Creative Cloud",
      vendorId: "11111111-1111-1111-1111-111111111111",
      seatsTotal: 10,
      expiryDate: "2027-01-15",
      licenseType: "subscription",
    });

    expect(result.ok).toBe(true);
    if (result.ok) {
      expect(result.value).toMatchObject({
        name: "Adobe Creative Cloud",
        vendorId: "11111111-1111-1111-1111-111111111111",
        seatsTotal: 10,
        licenseType: "subscription",
      });
      expect(result.value.expiryDate).toBeInstanceOf(Date);
    }
  });

  it("accepts valid input with no expiryDate (perpetual license)", () => {
    const result = validateCreateLicenseInput({
      name: "Windows Server 2022",
      vendorId: "11111111-1111-1111-1111-111111111111",
      seatsTotal: 5,
      licenseType: "perpetual",
    });

    expect(result.ok).toBe(true);
    if (result.ok) {
      expect(result.value.expiryDate).toBeUndefined();
    }
  });

  it("rejects an empty name", () => {
    const result = validateCreateLicenseInput({
      name: "",
      vendorId: "11111111-1111-1111-1111-111111111111",
      seatsTotal: 10,
      licenseType: "subscription",
    });

    expect(result.ok).toBe(false);
    if (!result.ok) {
      expect(result.error).toMatch(/name/i);
    }
  });

  it("rejects a vendorId that is not a valid UUID", () => {
    const result = validateCreateLicenseInput({
      name: "Adobe Creative Cloud",
      vendorId: "not-a-uuid",
      seatsTotal: 10,
      licenseType: "subscription",
    });

    expect(result.ok).toBe(false);
    if (!result.ok) {
      expect(result.error).toMatch(/vendorId/i);
    }
  });

  it("rejects a missing vendorId", () => {
    const result = validateCreateLicenseInput({
      name: "Adobe Creative Cloud",
      seatsTotal: 10,
      licenseType: "subscription",
    });

    expect(result.ok).toBe(false);
    if (!result.ok) {
      expect(result.error).toMatch(/vendorId/i);
    }
  });

  it("rejects a zero seatsTotal", () => {
    const result = validateCreateLicenseInput({
      name: "Adobe Creative Cloud",
      vendorId: "11111111-1111-1111-1111-111111111111",
      seatsTotal: 0,
      licenseType: "subscription",
    });

    expect(result.ok).toBe(false);
    if (!result.ok) {
      expect(result.error).toMatch(/seatsTotal/i);
    }
  });

  it("rejects a negative seatsTotal", () => {
    const result = validateCreateLicenseInput({
      name: "Adobe Creative Cloud",
      vendorId: "11111111-1111-1111-1111-111111111111",
      seatsTotal: -5,
      licenseType: "subscription",
    });

    expect(result.ok).toBe(false);
    if (!result.ok) {
      expect(result.error).toMatch(/seatsTotal/i);
    }
  });

  it("rejects a non-integer seatsTotal", () => {
    const result = validateCreateLicenseInput({
      name: "Adobe Creative Cloud",
      vendorId: "11111111-1111-1111-1111-111111111111",
      seatsTotal: 3.5,
      licenseType: "subscription",
    });

    expect(result.ok).toBe(false);
    if (!result.ok) {
      expect(result.error).toMatch(/seatsTotal/i);
    }
  });

  it("rejects an invalid expiryDate", () => {
    const result = validateCreateLicenseInput({
      name: "Adobe Creative Cloud",
      vendorId: "11111111-1111-1111-1111-111111111111",
      seatsTotal: 10,
      expiryDate: "not-a-date",
      licenseType: "subscription",
    });

    expect(result.ok).toBe(false);
    if (!result.ok) {
      expect(result.error).toMatch(/expiryDate/i);
    }
  });

  it("rejects an invalid licenseType", () => {
    const result = validateCreateLicenseInput({
      name: "Adobe Creative Cloud",
      vendorId: "11111111-1111-1111-1111-111111111111",
      seatsTotal: 10,
      licenseType: "trial",
    });

    expect(result.ok).toBe(false);
    if (!result.ok) {
      expect(result.error).toMatch(/licenseType/i);
    }
  });

  it("rejects a missing licenseType", () => {
    const result = validateCreateLicenseInput({
      name: "Adobe Creative Cloud",
      vendorId: "11111111-1111-1111-1111-111111111111",
      seatsTotal: 10,
    });

    expect(result.ok).toBe(false);
    if (!result.ok) {
      expect(result.error).toMatch(/licenseType/i);
    }
  });
});

describe("createLicense", () => {
  it("creates a license with seatsUsed always 0, regardless of client input", async () => {
    const vendor = await createTestVendor();
    const result = validateCreateLicenseInput({
      name: "Adobe Creative Cloud",
      vendorId: vendor.id,
      seatsTotal: 10,
      // @ts-expect-error -- seatsUsed is intentionally not part of
      // CreateLicenseInput; this simulates a client trying to sneak it in.
      seatsUsed: 999,
      expiryDate: "2027-01-15",
      licenseType: "subscription",
    });
    expect(result.ok).toBe(true);
    if (!result.ok) return;

    const created = await createLicense(result.value);
    expect(created.ok).toBe(true);
    if (!created.ok) return;
    const record = created.value;

    expect(record.seats_used).toBe(0);
    expect(record).toMatchObject({
      name: "Adobe Creative Cloud",
      vendor_id: vendor.id,
      seats_total: 10,
      license_type: "subscription",
    });
    expect(typeof record.id).toBe("string");
    expect(record.id.length).toBeGreaterThan(0);
    expect(Number.isNaN(Date.parse(record.expiry_date as string))).toBe(false);
    expect(Number.isNaN(Date.parse(record.created_at))).toBe(false);
  });

  it("creates a perpetual license with no expiryDate", async () => {
    const vendor = await createTestVendor();
    const result = validateCreateLicenseInput({
      name: "Windows Server 2022",
      vendorId: vendor.id,
      seatsTotal: 5,
      licenseType: "perpetual",
    });
    expect(result.ok).toBe(true);
    if (!result.ok) return;

    const created = await createLicense(result.value);
    expect(created.ok).toBe(true);
    if (!created.ok) return;
    const record = created.value;

    expect(record.expiry_date).toBeNull();
    expect(record.seats_used).toBe(0);
    expect(record.license_type).toBe("perpetual");
  });

  it("returns a clean error when vendorId doesn't reference an existing vendor", async () => {
    const result = validateCreateLicenseInput({
      name: "Adobe Creative Cloud",
      vendorId: "00000000-0000-0000-0000-000000000000",
      seatsTotal: 10,
      licenseType: "subscription",
    });
    expect(result.ok).toBe(true);
    if (!result.ok) return;

    const created = await createLicense(result.value);
    expect(created.ok).toBe(false);
    if (created.ok) return;
    expect(created.error).toMatch(/vendorId/i);
    expect(created.error).toMatch(/does not reference an existing vendor/i);

    const remaining = await prisma.license.findMany();
    expect(remaining).toHaveLength(0);
  });
});

describe("listLicenses", () => {
  it("lists created licenses, newest first", async () => {
    const vendor1 = await createTestVendor({ name: "Microsoft VN" });
    const vendor2 = await createTestVendor({ name: "Adobe VN" });

    const first = validateCreateLicenseInput({
      name: "Windows Server 2022",
      vendorId: vendor1.id,
      seatsTotal: 5,
      licenseType: "perpetual",
    });
    expect(first.ok).toBe(true);
    if (first.ok) await createLicense(first.value);

    // Ensure a distinct created_at ordering even on fast filesystems/clocks.
    await new Promise((resolve) => setTimeout(resolve, 5));

    const second = validateCreateLicenseInput({
      name: "Adobe Creative Cloud",
      vendorId: vendor2.id,
      seatsTotal: 10,
      licenseType: "subscription",
    });
    expect(second.ok).toBe(true);
    if (second.ok) await createLicense(second.value);

    const records = await listLicenses();

    expect(records).toHaveLength(2);
    // newest first
    expect(records[0]).toMatchObject({ name: "Adobe Creative Cloud", vendor_id: vendor2.id });
    expect(records[1]).toMatchObject({ name: "Windows Server 2022", vendor_id: vendor1.id });
  });

  it("returns an empty list when there are no licenses", async () => {
    const records = await listLicenses();
    expect(records).toEqual([]);
  });
});

describe("POST /api/licenses", () => {
  it("creates a license with seatsUsed always 0 on valid input", async () => {
    const vendor = await createTestVendor();
    const res = await POST(
      postRequest({
        name: "Adobe Creative Cloud",
        vendorId: vendor.id,
        seatsTotal: 10,
        expiryDate: "2027-01-15",
        licenseType: "subscription",
      })
    );

    expect(res.status).toBe(201);
    const body = await res.json();

    expect(body).toMatchObject({
      name: "Adobe Creative Cloud",
      vendor_id: vendor.id,
      seats_total: 10,
      seats_used: 0,
      license_type: "subscription",
    });
    expect(typeof body.id).toBe("string");
    expect(body.id.length).toBeGreaterThan(0);
    expect(Number.isNaN(Date.parse(body.expiry_date))).toBe(false);
    expect(Number.isNaN(Date.parse(body.created_at))).toBe(false);
  });

  it("creates a perpetual license with no expiryDate", async () => {
    const vendor = await createTestVendor();
    const res = await POST(
      postRequest({
        name: "Windows Server 2022",
        vendorId: vendor.id,
        seatsTotal: 5,
        licenseType: "perpetual",
      })
    );

    expect(res.status).toBe(201);
    const body = await res.json();
    expect(body.expiry_date).toBeNull();
    expect(body.seats_used).toBe(0);
  });

  it("rejects an empty name", async () => {
    const vendor = await createTestVendor();
    const res = await POST(
      postRequest({ name: "", vendorId: vendor.id, seatsTotal: 10, licenseType: "subscription" })
    );

    expect(res.status).toBe(400);
    const body = await res.json();
    expect(body.error).toMatch(/name/i);
  });

  it("rejects a vendorId that is not a valid UUID", async () => {
    const res = await POST(
      postRequest({
        name: "Adobe Creative Cloud",
        vendorId: "not-a-uuid",
        seatsTotal: 10,
        licenseType: "subscription",
      })
    );

    expect(res.status).toBe(400);
    const body = await res.json();
    expect(body.error).toMatch(/vendorId/i);
  });

  it("rejects a vendorId that is a well-formed UUID but doesn't reference an existing vendor", async () => {
    const res = await POST(
      postRequest({
        name: "Adobe Creative Cloud",
        vendorId: "00000000-0000-0000-0000-000000000000",
        seatsTotal: 10,
        licenseType: "subscription",
      })
    );

    expect(res.status).toBe(400);
    const body = await res.json();
    expect(body.error).toMatch(/vendorId/i);
    expect(body.error).toMatch(/does not reference an existing vendor/i);

    // And it must not have created anything.
    const remaining = await prisma.license.findMany();
    expect(remaining).toHaveLength(0);
  });

  it("rejects a zero seatsTotal", async () => {
    const vendor = await createTestVendor();
    const res = await POST(
      postRequest({ name: "Adobe Creative Cloud", vendorId: vendor.id, seatsTotal: 0, licenseType: "subscription" })
    );

    expect(res.status).toBe(400);
    const body = await res.json();
    expect(body.error).toMatch(/seatsTotal/i);
  });

  it("rejects an invalid expiryDate", async () => {
    const vendor = await createTestVendor();
    const res = await POST(
      postRequest({
        name: "Adobe Creative Cloud",
        vendorId: vendor.id,
        seatsTotal: 10,
        expiryDate: "not-a-date",
        licenseType: "subscription",
      })
    );

    expect(res.status).toBe(400);
    const body = await res.json();
    expect(body.error).toMatch(/expiryDate/i);
  });

  it("rejects an invalid licenseType", async () => {
    const vendor = await createTestVendor();
    const res = await POST(
      postRequest({ name: "Adobe Creative Cloud", vendorId: vendor.id, seatsTotal: 10, licenseType: "trial" })
    );

    expect(res.status).toBe(400);
    const body = await res.json();
    expect(body.error).toMatch(/licenseType/i);
  });

  it("rejects an invalid JSON body", async () => {
    const req = new Request("http://localhost/api/licenses", {
      method: "POST",
      headers: { "content-type": "application/json" },
      body: "not json",
    });

    const res = await POST(req);
    expect(res.status).toBe(400);
    const body = await res.json();
    expect(body.error).toMatch(/JSON/i);
  });

  it("rejects a non-object JSON body", async () => {
    // Note: arrays are `typeof "object"` in JS, so they pass the route's
    // object check (same behavior as /api/assets) — use a JSON string
    // primitive here to actually exercise the "not an object" branch.
    const res = await POST(postRequest("not an object"));

    expect(res.status).toBe(400);
    const body = await res.json();
    expect(body.error).toMatch(/JSON object/i);
  });
});

describe("GET /api/licenses", () => {
  it("lists created licenses, newest first", async () => {
    const vendor1 = await createTestVendor({ name: "Microsoft VN" });
    const vendor2 = await createTestVendor({ name: "Adobe VN" });

    await POST(
      postRequest({ name: "Windows Server 2022", vendorId: vendor1.id, seatsTotal: 5, licenseType: "perpetual" })
    );
    // Ensure a distinct created_at ordering even on fast filesystems/clocks.
    await new Promise((resolve) => setTimeout(resolve, 5));
    await POST(
      postRequest({ name: "Adobe Creative Cloud", vendorId: vendor2.id, seatsTotal: 10, licenseType: "subscription" })
    );

    const res = await GET();
    expect(res.status).toBe(200);

    const body = await res.json();
    expect(Array.isArray(body)).toBe(true);
    expect(body).toHaveLength(2);

    // newest first
    expect(body[0]).toMatchObject({ name: "Adobe Creative Cloud", vendor_id: vendor2.id });
    expect(body[1]).toMatchObject({ name: "Windows Server 2022", vendor_id: vendor1.id });
  });

  it("returns an empty list when there are no licenses", async () => {
    const res = await GET();
    expect(res.status).toBe(200);
    const body = await res.json();
    expect(body).toEqual([]);
  });
});

describe("auth gating on /api/licenses", () => {
  // Mirrors tests/assets.test.ts's "auth gating" block — only checks
  // session presence, per the flat permission model (no role/permission
  // logic).
  it("POST /api/licenses returns 401 without a session", async () => {
    const vendor = await createTestVendor();
    mockedAuth.mockResolvedValue(null);

    const res = await POST(
      postRequest({ name: "Adobe Creative Cloud", vendorId: vendor.id, seatsTotal: 10, licenseType: "subscription" })
    );

    expect(res.status).toBe(401);
    const body = await res.json();
    expect(body).toEqual({ error: "Unauthorized" });

    // And it must not have created anything.
    const remaining = await prisma.license.findMany();
    expect(remaining).toHaveLength(0);
  });

  it("GET /api/licenses returns 401 without a session", async () => {
    mockedAuth.mockResolvedValue(null);

    const res = await GET();

    expect(res.status).toBe(401);
    const body = await res.json();
    expect(body).toEqual({ error: "Unauthorized" });
  });
});