'use strict';

const createError = require('http-errors');
const { issueVHL } = require('../services/vhlIssue');

/**
 * POST /vhl/:patientId
 *
 * Issues a Verifiable Health Link (VHL) for a patient.
 * Corresponds to Fase 1 (Emisión) in obtener_qr_vhl.mmd:
 *   MiArgentina → BusNación: solicita generación de VHL para [PacienteID]
 *   BusNación   → MiArgentina: retorna VHL firmado (CWT)
 *
 * Path parameter:
 *   :patientId  — FHIR Patient logical ID in the local HAPI FHIR server.
 *
 * Body (optional, application/json):
 *   { "pin": "1234" }   ← citizen-configured PIN; protects the manifest.
 *
 * Response 201:
 *   { "cwt": "<base64url COSE_Sign1>" }
 *
 * MiArgentina then:
 *   - Decodes the base64url to get the CWT bytes.
 *   - Compresses with ZLIB and encodes as Base45 to produce the QR payload.
 *   - Displays the QR code to the citizen.
 */
async function issueVHLController(req, res, next) {
    try {
        const { patientId } = req.params;
        if (!patientId) {
            throw createError(400, 'Missing path parameter: patientId');
        }

        const pin = req.body && typeof req.body.pin === 'string'
            ? req.body.pin.trim() || undefined
            : undefined;

        const result = await issueVHL({ patientId, pin });
        res.status(201).json(result);
    } catch (err) {
        next(err);
    }
}

module.exports = { issueVHLController };