export interface ContactEmailData {
  formData?: Record<string, string>;
  message?: string;
  email?: string;
}

function createMessage(data: ContactEmailData): string {
  if (data.message && data.message.trim()) {
    return data.message.trim();
  }

  if (data.formData && Object.keys(data.formData).length > 0) {
    if (data.formData.message && data.formData.message.trim()) {
      return data.formData.message.trim();
    }

    const lines: string[] = [];
    Object.entries(data.formData).forEach(([key, value]) => {
      if (value && value.trim()) {
        const fieldName = key.charAt(0).toUpperCase() + key.slice(1).replace(/([A-Z])/g, ' $1');
        lines.push(`${fieldName}: ${value.trim()}`);
      }
    });

    if (lines.length > 0) {
      return lines.join('\n\n');
    }
  }

  return 'A new contact form submission has been received.';
}

export async function sendContactEmail(data: ContactEmailData): Promise<Response> {
  const message = createMessage(data);
  const fromEmail = data.formData?.email || data.email || 'noreply@example.com';

  const apiUrl = process.env.NEXT_PUBLIC_API_URL;
  const projectId = process.env.NEXT_PUBLIC_PROJECT_ID;

  if (!apiUrl || !projectId) {
    throw new Error('NEXT_PUBLIC_API_URL and NEXT_PUBLIC_PROJECT_ID must be set');
  }

  const response = await fetch(`${apiUrl}/emails/projects/${projectId}/sendMail`, {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
    },
    body: JSON.stringify({
      message,
      fromEmail,
      formData: data.formData,
    }),
  });

  if (!response.ok) {
    const error = await response.json().catch(() => ({ error: 'Failed to send email' }));
    throw new Error(error.error || 'Failed to send email');
  }

  return response;
}