import { cookies } from 'next/headers';
import { randomUUID } from 'crypto';
import type { AuthenticatedUserDTO } from '../../application/dto/AuthenticatedUserDTO';
import type { AuthSessionDTO } from '../../application/dto/AuthSessionDTO';
import type { IdentitySessionPort } from '../../application/ports/IdentitySessionPort';

const SESSION_COOKIE = 'gp_demo_session';

function parseCookieValue(raw: string | undefined): AuthSessionDTO | null {
  if (!raw) return null;
  try {
    const parsed = JSON.parse(raw) as AuthSessionDTO;
    if (!parsed.expiresAt || Date.now() > parsed.expiresAt) {
      return null;
    }
    return parsed;
  } catch {
    return null;
  }
}

function serializeSession(session: AuthSessionDTO): string {
  return JSON.stringify(session);
}

export class CookieIdentitySessionAdapter implements IdentitySessionPort {
  async getCurrentSession(): Promise<AuthSessionDTO | null> {
    const store = await cookies();
    const raw = store.get(SESSION_COOKIE)?.value;
    return parseCookieValue(raw);
  }

  async createSession(user: AuthenticatedUserDTO): Promise<AuthSessionDTO> {
    const now = Date.now();
    const expiresAt = now + 24 * 60 * 60 * 1000;

    const session: AuthSessionDTO = {
      user,
      issuedAt: now,
      expiresAt,
      token: randomUUID(),
    };

    const store = await cookies();
    store.set(SESSION_COOKIE, serializeSession(session), {
      httpOnly: true,
      sameSite: 'lax',
      path: '/',
      secure: process.env.NODE_ENV === 'production',
    });

    return session;
  }

  async clearSession(): Promise<void> {
    const store = await cookies();
    store.delete(SESSION_COOKIE);
  }
}