import { describe, it, expect, beforeEach, afterEach } from "vitest";
import { createMocks } from "node-mocks-http";
import { GET, POST } from "@/app/api/dashboard/users/route";
import { prisma } from "@/lib/prisma";

// Mock the database
const mockUser = {
  id: "admin-user-id",
  email: "admin@example.com",
  role: "ADMIN",
  companyId: "test-company-id",
};

const mockCompany = {
  id: "test-company-id",
  name: "Test Company",
};

const mockExistingUsers = [
  {
    id: "user-1",
    email: "existing@example.com",
    role: "USER",
    companyId: "test-company-id",
  },
  {
    id: "user-2",
    email: "admin@example.com",
    role: "ADMIN",
    companyId: "test-company-id",
  },
];

describe("User Invitation Integration Tests", () => {
  beforeEach(() => {
    // Mock Prisma methods
    prisma.user = {
      findMany: async () => mockExistingUsers,
      findUnique: async () => mockUser,
      create: async (data: any) => ({
        id: "new-user-id",
        email: data.data.email,
        role: data.data.role,
        companyId: data.data.companyId,
        createdAt: new Date(),
        updatedAt: new Date(),
        passwordHash: null,
        isActive: true,
        lastLoginAt: null,
      }),
    } as any;

    prisma.company = {
      findUnique: async () => mockCompany,
    } as any;
  });

  afterEach(() => {
    // Clean up any mocks
  });

  describe("GET /api/dashboard/users", () => {
    it("should return users for authenticated admin", async () => {
      const { req, res } = createMocks({
        method: "GET",
        headers: {
          "content-type": "application/json",
        },
      });

      // Mock authentication
      (req as any).auth = {
        user: mockUser,
      };

      await GET(req as any);

      expect(res._getStatusCode()).toBe(200);
      const data = JSON.parse(res._getData());
      expect(data.users).toHaveLength(2);
      expect(data.users[0].email).toBe("existing@example.com");
    });

    it("should deny access for non-admin users", async () => {
      const { req, res } = createMocks({
        method: "GET",
      });

      // Mock non-admin user
      (req as any).auth = {
        user: { ...mockUser, role: "USER" },
      };

      await GET(req as any);

      expect(res._getStatusCode()).toBe(403);
      const data = JSON.parse(res._getData());
      expect(data.error).toBe("Access denied. Admin role required.");
    });

    it("should deny access for unauthenticated requests", async () => {
      const { req, res } = createMocks({
        method: "GET",
      });

      await GET(req as any);

      expect(res._getStatusCode()).toBe(401);
      const data = JSON.parse(res._getData());
      expect(data.error).toBe("Unauthorized");
    });
  });

  describe("POST /api/dashboard/users", () => {
    it("should successfully invite a new user", async () => {
      const { req, res } = createMocks({
        method: "POST",
        body: {
          email: "newuser@example.com",
          role: "USER",
        },
        headers: {
          "content-type": "application/json",
        },
      });

      // Mock authentication
      (req as any).auth = {
        user: mockUser,
      };

      await POST(req as any);

      expect(res._getStatusCode()).toBe(201);
      const data = JSON.parse(res._getData());
      expect(data.message).toBe("User invited successfully");
      expect(data.user.email).toBe("newuser@example.com");
      expect(data.user.role).toBe("USER");
    });

    it("should prevent duplicate email invitations", async () => {
      const { req, res } = createMocks({
        method: "POST",
        body: {
          email: "existing@example.com",
          role: "USER",
        },
      });

      // Mock Prisma to simulate existing user
      prisma.user.findUnique = async () => mockExistingUsers[0] as any;

      (req as any).auth = {
        user: mockUser,
      };

      await POST(req as any);

      expect(res._getStatusCode()).toBe(400);
      const data = JSON.parse(res._getData());
      expect(data.error).toBe("User with this email already exists");
    });

    it("should validate email format", async () => {
      const { req, res } = createMocks({
        method: "POST",
        body: {
          email: "invalid-email",
          role: "USER",
        },
      });

      (req as any).auth = {
        user: mockUser,
      };

      await POST(req as any);

      expect(res._getStatusCode()).toBe(400);
      const data = JSON.parse(res._getData());
      expect(data.error).toContain("Invalid email format");
    });

    it("should validate role values", async () => {
      const { req, res } = createMocks({
        method: "POST",
        body: {
          email: "test@example.com",
          role: "INVALID_ROLE",
        },
      });

      (req as any).auth = {
        user: mockUser,
      };

      await POST(req as any);

      expect(res._getStatusCode()).toBe(400);
      const data = JSON.parse(res._getData());
      expect(data.error).toContain("Invalid role");
    });

    it("should require email field", async () => {
      const { req, res } = createMocks({
        method: "POST",
        body: {
          role: "USER",
        },
      });

      (req as any).auth = {
        user: mockUser,
      };

      await POST(req as any);

      expect(res._getStatusCode()).toBe(400);
      const data = JSON.parse(res._getData());
      expect(data.error).toContain("Email is required");
    });

    it("should require role field", async () => {
      const { req, res } = createMocks({
        method: "POST",
        body: {
          email: "test@example.com",
        },
      });

      (req as any).auth = {
        user: mockUser,
      };

      await POST(req as any);

      expect(res._getStatusCode()).toBe(400);
      const data = JSON.parse(res._getData());
      expect(data.error).toContain("Role is required");
    });

    it("should deny access for non-admin users", async () => {
      const { req, res } = createMocks({
        method: "POST",
        body: {
          email: "test@example.com",
          role: "USER",
        },
      });

      (req as any).auth = {
        user: { ...mockUser, role: "USER" },
      };

      await POST(req as any);

      expect(res._getStatusCode()).toBe(403);
      const data = JSON.parse(res._getData());
      expect(data.error).toBe("Access denied. Admin role required.");
    });

    it("should handle database errors gracefully", async () => {
      const { req, res } = createMocks({
        method: "POST",
        body: {
          email: "test@example.com",
          role: "USER",
        },
      });

      // Mock database error
      prisma.user.create = async () => {
        throw new Error("Database connection failed");
      };

      (req as any).auth = {
        user: mockUser,
      };

      await POST(req as any);

      expect(res._getStatusCode()).toBe(500);
      const data = JSON.parse(res._getData());
      expect(data.error).toBe("Internal server error");
    });

    it("should handle different role types correctly", async () => {
      const roles = ["USER", "ADMIN", "AUDITOR"];

      for (const role of roles) {
        const { req, res } = createMocks({
          method: "POST",
          body: {
            email: `${role.toLowerCase()}@example.com`,
            role: role,
          },
        });

        (req as any).auth = {
          user: mockUser,
        };

        await POST(req as any);

        expect(res._getStatusCode()).toBe(201);
        const data = JSON.parse(res._getData());
        expect(data.user.role).toBe(role);
      }
    });

    it("should associate user with correct company", async () => {
      const { req, res } = createMocks({
        method: "POST",
        body: {
          email: "newuser@example.com",
          role: "USER",
        },
      });

      (req as any).auth = {
        user: mockUser,
      };

      await POST(req as any);

      expect(res._getStatusCode()).toBe(201);
      const data = JSON.parse(res._getData());
      expect(data.user.companyId).toBe(mockUser.companyId);
    });
  });

  describe("Email Validation Edge Cases", () => {
    it("should handle very long email addresses", async () => {
      const longEmail = "a".repeat(250) + "@example.com";

      const { req, res } = createMocks({
        method: "POST",
        body: {
          email: longEmail,
          role: "USER",
        },
      });

      (req as any).auth = {
        user: mockUser,
      };

      await POST(req as any);

      expect(res._getStatusCode()).toBe(400);
      const data = JSON.parse(res._getData());
      expect(data.error).toContain("Email too long");
    });

    it("should handle special characters in email", async () => {
      const specialEmail = "test+tag@example-domain.co.uk";

      const { req, res } = createMocks({
        method: "POST",
        body: {
          email: specialEmail,
          role: "USER",
        },
      });

      (req as any).auth = {
        user: mockUser,
      };

      await POST(req as any);

      expect(res._getStatusCode()).toBe(201);
      const data = JSON.parse(res._getData());
      expect(data.user.email).toBe(specialEmail);
    });

    it("should normalize email case", async () => {
      const { req, res } = createMocks({
        method: "POST",
        body: {
          email: "TEST@EXAMPLE.COM",
          role: "USER",
        },
      });

      (req as any).auth = {
        user: mockUser,
      };

      await POST(req as any);

      expect(res._getStatusCode()).toBe(201);
      const data = JSON.parse(res._getData());
      expect(data.user.email).toBe("test@example.com");
    });
  });

  describe("Concurrent Request Handling", () => {
    it("should handle concurrent invitations for the same email", async () => {
      const email = "concurrent@example.com";

      // Create multiple requests for the same email
      const requests = Array.from({ length: 3 }, () => {
        const { req } = createMocks({
          method: "POST",
          body: { email, role: "USER" },
        });
        (req as any).auth = { user: mockUser };
        return req;
      });

      // Execute requests concurrently
      const results = await Promise.allSettled(
        requests.map(req => POST(req as any))
      );

      // Only one should succeed, others should fail with conflict
      const successful = results.filter(r => r.status === "fulfilled").length;
      expect(successful).toBe(1);
    });
  });

  describe("Rate Limiting", () => {
    it("should handle multiple rapid invitations", async () => {
      const emails = [
        "user1@example.com",
        "user2@example.com",
        "user3@example.com",
        "user4@example.com",
        "user5@example.com",
      ];

      const results = [];

      for (const email of emails) {
        const { req, res } = createMocks({
          method: "POST",
          body: { email, role: "USER" },
        });

        (req as any).auth = { user: mockUser };

        await POST(req as any);
        results.push({
          email,
          status: res._getStatusCode(),
          data: JSON.parse(res._getData()),
        });
      }

      // All should succeed (no rate limiting implemented yet)
      results.forEach(result => {
        expect(result.status).toBe(201);
        expect(result.data.user.email).toBe(result.email);
      });
    });
  });
});