import {
  authenticate,
  createSeatHandover,
  revokeSeatHandover,
  claimSeatHandover,
  recoverSeat,
  SeatControlError,
  setRecoveryKey,
} from '@/db/rooms';
import { RuleError } from '@/game/engine';
const noStore = { 'Cache-Control': 'no-store' };
export async function POST(req: Request) {
  try {
    const url = new URL(req.url);
    if (req.headers.get('origin') && req.headers.get('origin') !== url.origin)
      throw new SeatControlError(
        'Invalid request origin.',
        'INVALID_ORIGIN',
        403,
      );
    const code = url.pathname.split('/').at(-2)!.toUpperCase();
    if (!/^[A-Z2-9]{8}$/.test(code))
      throw new SeatControlError(
        'Enter the eight-character room code.',
        'INVALID_CONTROL_REQUEST',
        400,
      );
    const raw = await req.text();
    if (raw.length > 4000)
      throw new SeatControlError(
        'Request too large.',
        'REQUEST_TOO_LARGE',
        413,
      );
    const body: unknown = JSON.parse(raw);
    if (!body || typeof body !== 'object' || Array.isArray(body))
      throw new SeatControlError(
        'Choose a recovery operation.',
        'INVALID_CONTROL_REQUEST',
        400,
      );
    const input = body as Record<string, unknown>;
    const token =
      req.headers
        .get('cookie')
        ?.split(';')
        .map((part) => part.trim())
        .find((part) => part.startsWith(`dune_${code}=`))
        ?.split('=')[1] ?? '';
    if (
      input.type === 'setRecoveryKey' ||
      input.type === 'createSeatHandover' ||
      input.type === 'revokeSeatHandover'
    ) {
      const auth = await authenticate(code, token);
      if (input.type === 'createSeatHandover')
        return Response.json(
          await createSeatHandover(code, auth, input.version, {
            offerId: input.offerId,
            handoverSecret: input.handoverSecret,
          }),
          { headers: noStore },
        );
      if (input.type === 'revokeSeatHandover')
        return Response.json(
          await revokeSeatHandover(code, auth, input.version, input.offerId),
          { headers: noStore },
        );
      return Response.json(
        await setRecoveryKey(code, auth, input.version, input.recoverySecret),
        { headers: noStore },
      );
    }
    if (input.type !== 'recoverSeat' && input.type !== 'claimSeatHandover')
      throw new SeatControlError(
        'Choose a recovery operation.',
        'INVALID_CONTROL_REQUEST',
        400,
      );
    if (input.type === 'claimSeatHandover' && token) {
      let existing;
      try {
        existing = await authenticate(code, token);
      } catch (error) {
        if (!(error instanceof RuleError)) throw error;
      }
      if (existing && existing.playerId !== input.playerId)
        throw new SeatControlError(
          'This browser already controls another seat in this room. Use a separate browser profile to accept the handover.',
          'ALREADY_SEATED',
          409,
        );
    }
    const result =
      input.type === 'claimSeatHandover'
        ? await claimSeatHandover(code, {
            playerId: input.playerId,
            offerId: input.offerId,
            handoverSecret: input.handoverSecret,
            operationId: input.operationId,
            newSessionToken: input.newSessionToken,
          })
        : await recoverSeat(code, {
            playerId: input.playerId,
            recoverySecret: input.recoverySecret,
            operationId: input.operationId,
            newSessionToken: input.newSessionToken,
          });
    return Response.json(
      {
        view: result.view,
        ...('transferred' in result
          ? { transferred: result.transferred }
          : { recovered: result.recovered }),
        replayed: result.replayed,
      },
      {
        headers: {
          ...noStore,
          'Set-Cookie': `dune_${code}=${result.token}; HttpOnly; SameSite=Strict; Path=/api/rooms/${code}; Max-Age=2592000${url.protocol === 'https:' ? '; Secure' : ''}`,
        },
      },
    );
  } catch (error) {
    return Response.json(
      {
        error:
          error instanceof RuleError
            ? error.message
            : error instanceof SyntaxError
              ? 'Invalid JSON.'
              : 'The server could not complete this seat request.',
        code:
          error instanceof SeatControlError
            ? error.code
            : error instanceof RuleError
              ? 'INVALID_SESSION'
              : error instanceof SyntaxError
                ? 'INVALID_CONTROL_REQUEST'
                : 'SERVER_ERROR',
      },
      {
        status:
          error instanceof SeatControlError
            ? error.status
            : error instanceof RuleError
              ? 409
              : error instanceof SyntaxError
                ? 400
                : 500,
        headers: noStore,
      },
    );
  }
}