/**
 * Cloud Instances API Tester
 *
 * Comprehensive test suite for API endpoints with colorful console output.
 * Tests all endpoints with various parameter combinations and validates responses.
 *
 * Requirements:
 *   API_KEY environment variable must be set
 *
 * Usage:
 *   export API_KEY=your-api-key-here
 *   npx tsx scripts/api-tester.ts
 *   npx tsx scripts/api-tester.ts --endpoint /health
 *   npx tsx scripts/api-tester.ts --verbose
 *
 * Or use npm scripts:
 *   npm run test:api
 *   npm run test:api:verbose
 */

// ============================================================
// Configuration
// ============================================================

const API_URL = process.env.API_URL || 'https://cloud-instances-api.kappa-d8e.workers.dev';
const API_KEY = process.env.API_KEY;

if (!API_KEY) {
  console.error('\n❌ ERROR: API_KEY environment variable is required');
  console.error('Please set API_KEY before running the tests:');
  console.error('  export API_KEY=your-api-key-here');
  console.error('  npm run test:api');
  console.error('\nOr create a .env file (see .env.example for reference)');
  process.exit(1);
}

if (API_KEY.length < 16) {
  console.error('\n❌ ERROR: API_KEY must be at least 16 characters');
  console.error('The provided API key is too short to be valid.');
  console.error('Please check your API_KEY environment variable.');
  process.exit(1);
}

// CLI flags
const args = process.argv.slice(2);
const VERBOSE = args.includes('--verbose');
const TARGET_ENDPOINT = args.find(arg => arg.startsWith('--endpoint='))?.split('=')[1];

// ============================================================
// Color Utilities
// ============================================================

const colors = {
  reset: '\x1b[0m',
  bold: '\x1b[1m',
  dim: '\x1b[2m',
  red: '\x1b[31m',
  green: '\x1b[32m',
  yellow: '\x1b[33m',
  blue: '\x1b[34m',
  magenta: '\x1b[35m',
  cyan: '\x1b[36m',
  white: '\x1b[37m',
  gray: '\x1b[90m',
};

function color(text: string, colorCode: string): string {
  return `${colorCode}${text}${colors.reset}`;
}

function bold(text: string): string {
  return `${colors.bold}${text}${colors.reset}`;
}

// ============================================================
// Test Result Types
// ============================================================

interface TestResult {
  name: string;
  endpoint: string;
  method: string;
  passed: boolean;
  duration: number;
  statusCode?: number;
  error?: string;
  details?: string;
}

interface TestReport {
  total: number;
  passed: number;
  failed: number;
  duration: number;
  results: TestResult[];
}

// ============================================================
// API Test Helper
// ============================================================

// Delay utility to avoid rate limiting (100 req/min = 600ms minimum between requests)
async function delay(ms: number): Promise<void> {
  return new Promise(resolve => setTimeout(resolve, ms));
}

// Helper to add delay between tests (delay BEFORE request to ensure rate limit compliance)
async function testWithDelay(
  name: string,
  endpoint: string,
  options: Parameters<typeof testRequest>[2] = {}
): Promise<TestResult> {
  await delay(800); // 800ms delay BEFORE request to avoid rate limiting (100 req/min)
  const result = await testRequest(name, endpoint, options);
  return result;
}

async function testRequest(
  name: string,
  endpoint: string,
  options: {
    method?: string;
    headers?: Record<string, string>;
    body?: unknown;
    expectStatus?: number | number[];
    validateResponse?: (data: unknown) => boolean | string;
  } = {}
): Promise<TestResult> {
  const {
    method = 'GET',
    headers = {},
    body,
    expectStatus = 200,
    validateResponse,
  } = options;

  // Convert expectStatus to array for easier checking
  const expectedStatuses = Array.isArray(expectStatus) ? expectStatus : [expectStatus];

  const startTime = Date.now();
  const url = `${API_URL}${endpoint}`;

  try {
    const requestHeaders: Record<string, string> = {
      'Content-Type': 'application/json',
      ...headers,
    };

    const response = await fetch(url, {
      method,
      headers: requestHeaders,
      body: body ? JSON.stringify(body) : undefined,
    });

    const duration = Date.now() - startTime;
    const data = await response.json();

    // Check status code (supports multiple expected statuses)
    if (!expectedStatuses.includes(response.status)) {
      return {
        name,
        endpoint,
        method,
        passed: false,
        duration,
        statusCode: response.status,
        error: `Expected status ${expectedStatuses.join(' or ')}, got ${response.status}`,
        details: JSON.stringify(data, null, 2),
      };
    }

    // Validate response structure
    if (validateResponse) {
      const validationResult = validateResponse(data);
      if (validationResult !== true) {
        return {
          name,
          endpoint,
          method,
          passed: false,
          duration,
          statusCode: response.status,
          error: typeof validationResult === 'string' ? validationResult : 'Response validation failed',
          details: JSON.stringify(data, null, 2),
        };
      }
    }

    return {
      name,
      endpoint,
      method,
      passed: true,
      duration,
      statusCode: response.status,
      details: VERBOSE ? JSON.stringify(data, null, 2) : undefined,
    };
  } catch (error) {
    const duration = Date.now() - startTime;
    return {
      name,
      endpoint,
      method,
      passed: false,
      duration,
      error: error instanceof Error ? error.message : String(error),
    };
  }
}

// ============================================================
// Response Validators
// ============================================================

function validateHealthResponse(data: unknown): boolean | string {
  if (typeof data !== 'object' || data === null) {
    return 'Response is not an object';
  }

  const response = data as Record<string, unknown>;

  if (!response.status || typeof response.status !== 'string') {
    return 'Missing or invalid status field';
  }

  // Accept both 'healthy' and 'degraded' status
  if (response.status !== 'healthy' && response.status !== 'degraded') {
    return `Invalid status value: ${response.status}`;
  }

  if (!response.timestamp || typeof response.timestamp !== 'string') {
    return 'Missing or invalid timestamp field';
  }

  return true;
}

function validateInstancesResponse(data: unknown): boolean | string {
  if (typeof data !== 'object' || data === null) {
    return 'Response is not an object';
  }

  const response = data as Record<string, unknown>;

  if (!response.success) {
    return 'Response success field is false or missing';
  }

  if (!response.data || typeof response.data !== 'object') {
    return 'Missing or invalid data field';
  }

  const responseData = response.data as Record<string, unknown>;

  if (!Array.isArray(responseData.instances)) {
    return 'Missing or invalid instances array';
  }

  if (!responseData.pagination || typeof responseData.pagination !== 'object') {
    return 'Missing or invalid pagination field';
  }

  return true;
}

function validateSyncResponse(data: unknown): boolean | string {
  if (typeof data !== 'object' || data === null) {
    return 'Response is not an object';
  }

  const response = data as Record<string, unknown>;

  if (typeof response.success !== 'boolean') {
    return 'Missing or invalid success field';
  }

  if (response.success && (!response.data || typeof response.data !== 'object')) {
    return 'Missing or invalid data field for successful sync';
  }

  return true;
}

// ============================================================
// Test Suites
// ============================================================

async function testHealthEndpoint(): Promise<TestResult[]> {
  console.log(color('\n📍 Testing /health', colors.cyan));

  const tests: TestResult[] = [];

  // Test without authentication (200 or 503 for degraded status)
  tests.push(
    await testWithDelay('GET /health (no auth)', '/health', {
      expectStatus: [200, 503], // 503 is valid when system is degraded
      validateResponse: validateHealthResponse,
    })
  );

  // Test with authentication (200 or 503 for degraded status)
  tests.push(
    await testWithDelay('GET /health (with auth)', '/health', {
      headers: { 'X-API-Key': API_KEY },
      expectStatus: [200, 503], // 503 is valid when system is degraded
      validateResponse: validateHealthResponse,
    })
  );

  return tests;
}

async function testInstancesEndpoint(): Promise<TestResult[]> {
  console.log(color('\n📍 Testing /instances', colors.cyan));

  const tests: TestResult[] = [];

  // Test basic query
  tests.push(
    await testWithDelay('GET /instances (basic)', '/instances', {
      headers: { 'X-API-Key': API_KEY },
      expectStatus: 200,
      validateResponse: validateInstancesResponse,
    })
  );

  // Test provider filter
  tests.push(
    await testWithDelay('GET /instances?provider=linode', '/instances?provider=linode', {
      headers: { 'X-API-Key': API_KEY },
      expectStatus: 200,
      validateResponse: validateInstancesResponse,
    })
  );

  // Test memory filter
  tests.push(
    await testWithDelay('GET /instances?min_memory_gb=4', '/instances?min_memory_gb=4', {
      headers: { 'X-API-Key': API_KEY },
      expectStatus: 200,
      validateResponse: validateInstancesResponse,
    })
  );

  // Test vCPU filter
  tests.push(
    await testWithDelay('GET /instances?min_vcpu=2&max_vcpu=8', '/instances?min_vcpu=2&max_vcpu=8', {
      headers: { 'X-API-Key': API_KEY },
      expectStatus: 200,
      validateResponse: validateInstancesResponse,
    })
  );

  // Test price filter
  tests.push(
    await testWithDelay('GET /instances?max_price=50', '/instances?max_price=50', {
      headers: { 'X-API-Key': API_KEY },
      expectStatus: 200,
      validateResponse: validateInstancesResponse,
    })
  );

  // Test GPU filter
  tests.push(
    await testWithDelay('GET /instances?has_gpu=true', '/instances?has_gpu=true', {
      headers: { 'X-API-Key': API_KEY },
      expectStatus: 200,
      validateResponse: validateInstancesResponse,
    })
  );

  // Test sorting
  tests.push(
    await testWithDelay('GET /instances?sort_by=price&order=asc', '/instances?sort_by=price&order=asc', {
      headers: { 'X-API-Key': API_KEY },
      expectStatus: 200,
      validateResponse: validateInstancesResponse,
    })
  );

  // Test pagination
  tests.push(
    await testWithDelay('GET /instances?limit=10&offset=0', '/instances?limit=10&offset=0', {
      headers: { 'X-API-Key': API_KEY },
      expectStatus: 200,
      validateResponse: validateInstancesResponse,
    })
  );

  // Test combined filters
  tests.push(
    await testWithDelay('GET /instances (combined)', '/instances?provider=linode&min_vcpu=2&max_price=100&sort_by=price&order=asc', {
      headers: { 'X-API-Key': API_KEY },
      expectStatus: 200,
      validateResponse: validateInstancesResponse,
    })
  );

  // Test invalid provider (should fail)
  tests.push(
    await testWithDelay('GET /instances?provider=invalid (error)', '/instances?provider=invalid', {
      headers: { 'X-API-Key': API_KEY },
      expectStatus: 400,
    })
  );

  // Test without auth (should fail)
  tests.push(
    await testWithDelay('GET /instances (no auth - error)', '/instances', {
      expectStatus: 401,
    })
  );

  return tests;
}

async function testSyncEndpoint(): Promise<TestResult[]> {
  console.log(color('\n📍 Testing /sync', colors.cyan));

  const tests: TestResult[] = [];

  // Test Linode sync
  tests.push(
    await testWithDelay('POST /sync (linode)', '/sync', {
      method: 'POST',
      headers: { 'X-API-Key': API_KEY },
      body: { providers: ['linode'] },
      expectStatus: 200,
      validateResponse: validateSyncResponse,
    })
  );

  // Test without auth (should fail)
  tests.push(
    await testWithDelay('POST /sync (no auth - error)', '/sync', {
      method: 'POST',
      body: { providers: ['linode'] },
      expectStatus: 401,
    })
  );

  // Test invalid provider (should fail)
  tests.push(
    await testWithDelay('POST /sync (invalid provider - error)', '/sync', {
      method: 'POST',
      headers: { 'X-API-Key': API_KEY },
      body: { providers: ['invalid'] },
      expectStatus: 400,
    })
  );

  return tests;
}

// ============================================================
// Test Runner
// ============================================================

function printTestResult(result: TestResult): void {
  const icon = result.passed ? color('✅', colors.green) : color('❌', colors.red);
  const statusColor = result.passed ? colors.green : colors.red;
  const statusText = result.statusCode ? `${result.statusCode}` : 'ERROR';

  let output = `  ${icon} ${result.name} - ${color(statusText, statusColor)}`;

  if (result.passed) {
    output += ` ${color(`(${result.duration}ms)`, colors.gray)}`;
    if (result.details && VERBOSE) {
      output += `\n${color('    Response:', colors.gray)}\n${result.details.split('\n').map(line => `    ${line}`).join('\n')}`;
    }
  } else {
    output += ` ${color(`(${result.duration}ms)`, colors.gray)}`;
    if (result.error) {
      output += `\n    ${color('Error:', colors.red)} ${result.error}`;
    }
    if (result.details && VERBOSE) {
      output += `\n${color('    Response:', colors.gray)}\n${result.details.split('\n').map(line => `    ${line}`).join('\n')}`;
    }
  }

  console.log(output);
}

async function runTests(): Promise<TestReport> {
  const startTime = Date.now();
  const allResults: TestResult[] = [];

  console.log(bold(color('\n🧪 Cloud Instances API Tester', colors.cyan)));
  console.log(color('================================', colors.cyan));
  console.log(`${color('Target:', colors.white)} ${API_URL}`);
  const maskedKey = API_KEY.length > 4
    ? `${API_KEY.substring(0, 4)}${'*'.repeat(8)}`
    : '****';
  console.log(`${color('API Key:', colors.white)} ${maskedKey}`);
  if (VERBOSE) {
    console.log(color('Mode: VERBOSE', colors.yellow));
  }
  if (TARGET_ENDPOINT) {
    console.log(color(`Filter: ${TARGET_ENDPOINT}`, colors.yellow));
  }

  // Run test suites
  if (!TARGET_ENDPOINT || TARGET_ENDPOINT === '/health') {
    const healthResults = await testHealthEndpoint();
    healthResults.forEach(printTestResult);
    allResults.push(...healthResults);
  }

  if (!TARGET_ENDPOINT || TARGET_ENDPOINT === '/instances') {
    const instancesResults = await testInstancesEndpoint();
    instancesResults.forEach(printTestResult);
    allResults.push(...instancesResults);
  }

  if (!TARGET_ENDPOINT || TARGET_ENDPOINT === '/sync') {
    const syncResults = await testSyncEndpoint();
    syncResults.forEach(printTestResult);
    allResults.push(...syncResults);
  }

  const duration = Date.now() - startTime;
  const passed = allResults.filter(r => r.passed).length;
  const failed = allResults.filter(r => !r.passed).length;

  return {
    total: allResults.length,
    passed,
    failed,
    duration,
    results: allResults,
  };
}

function printReport(report: TestReport): void {
  console.log(color('\n================================', colors.cyan));
  console.log(bold(color('📊 Test Report', colors.cyan)));
  console.log(`  ${color('Total:', colors.white)} ${report.total} tests`);
  console.log(`  ${color('Passed:', colors.green)} ${report.passed} ${color('✅', colors.green)}`);
  console.log(`  ${color('Failed:', colors.red)} ${report.failed} ${color('❌', colors.red)}`);
  console.log(`  ${color('Duration:', colors.white)} ${(report.duration / 1000).toFixed(2)}s`);

  if (report.failed > 0) {
    console.log(color('\n⚠️  Failed Tests:', colors.yellow));
    report.results
      .filter(r => !r.passed)
      .forEach(r => {
        console.log(`  ${color('•', colors.red)} ${r.name}`);
        if (r.error) {
          console.log(`    ${color(r.error, colors.red)}`);
        }
      });
  }

  console.log('');
}

// ============================================================
// Main
// ============================================================

async function main(): Promise<void> {
  try {
    // Initial delay to ensure rate limit window is clear
    console.log(color('\n⏳ Waiting for rate limit window...', colors.gray));
    await delay(2000);

    const report = await runTests();
    printReport(report);

    // Exit with error code if any tests failed
    process.exit(report.failed > 0 ? 1 : 0);
  } catch (error) {
    console.error(color('\n❌ Fatal error:', colors.red), error);
    process.exit(1);
  }
}

main();