import { isEnvironment } from '../cli';

/**
 * Replicates the outputHeaderToPrefix logic from generate/client.ts for testing.
 */
function outputHeaderToPrefix(header: unknown): string {
  if (header == null || typeof header === 'function') return '';
  const lines =
    typeof header === 'string'
      ? header.split(/\r?\n/)
      : (header as string[]).flatMap((line) => line.split(/\r?\n/));
  const content = lines.join('\n');
  return content ? `${content}\n\n` : '';
}

describe('outputHeaderToPrefix logic', () => {
  it('returns default comment for string header', () => {
    const result = outputHeaderToPrefix('// This file is auto-generated by @hey-api/openapi-ts');
    expect(result).toBe('// This file is auto-generated by @hey-api/openapi-ts\n\n');
  });

  it('returns joined lines for array header', () => {
    const result = outputHeaderToPrefix([
      '// This file is auto-generated by @hey-api/openapi-ts',
      '// @ts-nocheck',
    ]);
    expect(result).toBe(
      '// This file is auto-generated by @hey-api/openapi-ts\n// @ts-nocheck\n\n',
    );
  });

  it('returns empty string for null header', () => {
    expect(outputHeaderToPrefix(null)).toBe('');
  });

  it('returns empty string for undefined header', () => {
    expect(outputHeaderToPrefix(undefined)).toBe('');
  });

  it('returns empty string for function header', () => {
    expect(outputHeaderToPrefix(() => '// dynamic')).toBe('');
  });

  it('handles string with embedded newlines', () => {
    const result = outputHeaderToPrefix('// line1\n// line2');
    expect(result).toBe('// line1\n// line2\n\n');
  });
});

describe('isEnvironment', () => {
  const originalEnv = process.env;

  beforeEach(() => {
    process.env = { ...originalEnv };
    delete process.env.HEYAPI_CODEGEN_ENV;
  });

  afterAll(() => {
    process.env = originalEnv;
  });

  it('returns false when env var is not set', () => {
    expect(isEnvironment('development')).toBe(false);
  });

  it('returns true when env var is set to "development"', () => {
    process.env.HEYAPI_CODEGEN_ENV = 'development';
    expect(isEnvironment('development')).toBe(true);
  });

  it('returns false when env var is set to other values', () => {
    process.env.HEYAPI_CODEGEN_ENV = '0';
    expect(isEnvironment('development')).toBe(false);

    process.env.HEYAPI_CODEGEN_ENV = 'false';
    expect(isEnvironment('development')).toBe(false);

    process.env.HEYAPI_CODEGEN_ENV = 'anything';
    expect(isEnvironment('development')).toBe(false);
  });
});