/**
 * Federation Configuration Tests
 *
 * Issue #338: Tests for DEFAULT_WORKSPACE_ID validation
 */

import { describe, it, expect, beforeEach, afterEach } from "vitest";
import {
  isValidUuidV4,
  getDefaultWorkspaceId,
  validateFederationConfig,
} from "./federation.config";

describe("federation.config", () => {
  const originalEnv = process.env.DEFAULT_WORKSPACE_ID;

  afterEach(() => {
    // Restore original environment
    if (originalEnv === undefined) {
      delete process.env.DEFAULT_WORKSPACE_ID;
    } else {
      process.env.DEFAULT_WORKSPACE_ID = originalEnv;
    }
  });

  describe("isValidUuidV4", () => {
    it("should return true for valid UUID v4", () => {
      const validUuids = [
        "123e4567-e89b-42d3-a456-426614174000",
        "550e8400-e29b-41d4-a716-446655440000",
        "6ba7b810-9dad-41d1-80b4-00c04fd430c8",
        "f47ac10b-58cc-4372-a567-0e02b2c3d479",
      ];

      for (const uuid of validUuids) {
        expect(isValidUuidV4(uuid)).toBe(true);
      }
    });

    it("should return true for uppercase UUID v4", () => {
      expect(isValidUuidV4("123E4567-E89B-42D3-A456-426614174000")).toBe(true);
    });

    it("should return false for non-v4 UUID (wrong version digit)", () => {
      // UUID v1 (version digit is 1)
      expect(isValidUuidV4("123e4567-e89b-12d3-a456-426614174000")).toBe(false);
      // UUID v3 (version digit is 3)
      expect(isValidUuidV4("123e4567-e89b-32d3-a456-426614174000")).toBe(false);
      // UUID v5 (version digit is 5)
      expect(isValidUuidV4("123e4567-e89b-52d3-a456-426614174000")).toBe(false);
    });

    it("should return false for invalid variant digit", () => {
      // Variant digit should be 8, 9, a, or b
      expect(isValidUuidV4("123e4567-e89b-42d3-0456-426614174000")).toBe(false);
      expect(isValidUuidV4("123e4567-e89b-42d3-7456-426614174000")).toBe(false);
      expect(isValidUuidV4("123e4567-e89b-42d3-c456-426614174000")).toBe(false);
    });

    it("should return false for non-UUID strings", () => {
      expect(isValidUuidV4("")).toBe(false);
      expect(isValidUuidV4("default")).toBe(false);
      expect(isValidUuidV4("not-a-uuid")).toBe(false);
      expect(isValidUuidV4("123e4567-e89b-12d3-a456")).toBe(false);
      expect(isValidUuidV4("123e4567e89b12d3a456426614174000")).toBe(false);
    });

    it("should return false for UUID with wrong length", () => {
      expect(isValidUuidV4("123e4567-e89b-42d3-a456-4266141740001")).toBe(false);
      expect(isValidUuidV4("123e4567-e89b-42d3-a456-42661417400")).toBe(false);
    });
  });

  describe("getDefaultWorkspaceId", () => {
    it("should return valid UUID when DEFAULT_WORKSPACE_ID is set correctly", () => {
      const validUuid = "123e4567-e89b-42d3-a456-426614174000";
      process.env.DEFAULT_WORKSPACE_ID = validUuid;

      expect(getDefaultWorkspaceId()).toBe(validUuid);
    });

    it("should trim whitespace from UUID", () => {
      const validUuid = "123e4567-e89b-42d3-a456-426614174000";
      process.env.DEFAULT_WORKSPACE_ID = `  ${validUuid}  `;

      expect(getDefaultWorkspaceId()).toBe(validUuid);
    });

    it("should throw error when DEFAULT_WORKSPACE_ID is not set", () => {
      delete process.env.DEFAULT_WORKSPACE_ID;

      expect(() => getDefaultWorkspaceId()).toThrow(
        "DEFAULT_WORKSPACE_ID environment variable is required for federation but is not set"
      );
    });

    it("should throw error when DEFAULT_WORKSPACE_ID is empty string", () => {
      process.env.DEFAULT_WORKSPACE_ID = "";

      expect(() => getDefaultWorkspaceId()).toThrow(
        "DEFAULT_WORKSPACE_ID environment variable is required for federation but is not set"
      );
    });

    it("should throw error when DEFAULT_WORKSPACE_ID is only whitespace", () => {
      process.env.DEFAULT_WORKSPACE_ID = "   ";

      expect(() => getDefaultWorkspaceId()).toThrow(
        "DEFAULT_WORKSPACE_ID environment variable is required for federation but is not set"
      );
    });

    it("should throw error when DEFAULT_WORKSPACE_ID is 'default' (not a valid UUID)", () => {
      process.env.DEFAULT_WORKSPACE_ID = "default";

      expect(() => getDefaultWorkspaceId()).toThrow("DEFAULT_WORKSPACE_ID must be a valid UUID v4");
      expect(() => getDefaultWorkspaceId()).toThrow('Current value "default" is not a valid UUID');
    });

    it("should throw error when DEFAULT_WORKSPACE_ID is invalid UUID format", () => {
      process.env.DEFAULT_WORKSPACE_ID = "not-a-valid-uuid";

      expect(() => getDefaultWorkspaceId()).toThrow("DEFAULT_WORKSPACE_ID must be a valid UUID v4");
    });

    it("should throw error for UUID v1 (wrong version)", () => {
      process.env.DEFAULT_WORKSPACE_ID = "123e4567-e89b-12d3-a456-426614174000";

      expect(() => getDefaultWorkspaceId()).toThrow("DEFAULT_WORKSPACE_ID must be a valid UUID v4");
    });

    it("should include helpful error message with expected format", () => {
      process.env.DEFAULT_WORKSPACE_ID = "invalid";

      expect(() => getDefaultWorkspaceId()).toThrow(
        "Expected format: xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx"
      );
    });
  });

  describe("validateFederationConfig", () => {
    it("should not throw when DEFAULT_WORKSPACE_ID is valid", () => {
      process.env.DEFAULT_WORKSPACE_ID = "123e4567-e89b-42d3-a456-426614174000";

      expect(() => validateFederationConfig()).not.toThrow();
    });

    it("should throw when DEFAULT_WORKSPACE_ID is missing", () => {
      delete process.env.DEFAULT_WORKSPACE_ID;

      expect(() => validateFederationConfig()).toThrow(
        "DEFAULT_WORKSPACE_ID environment variable is required for federation"
      );
    });

    it("should throw when DEFAULT_WORKSPACE_ID is invalid", () => {
      process.env.DEFAULT_WORKSPACE_ID = "invalid-uuid";

      expect(() => validateFederationConfig()).toThrow(
        "DEFAULT_WORKSPACE_ID must be a valid UUID v4"
      );
    });
  });
});