'use strict';

const { getManifest, getDocument } = require('../services/vhlVerify');

/**
 * POST /vhl/manifest/:manifestId
 *
 * Returns the VHL manifest for a given manifest ID.
 * Corresponds to Fase 4 step 6 in validar_qr_vhl.mmd:
 *   NodoDominio → BusNación: POST [Manifest_URL] (envía PIN si el ciudadano lo configuró)
 *   BusNación   → NodoDominio: 200 OK (retorna Manifest con link al NodoDominio_B)
 *
 * Path parameter:
 *   :manifestId — ID portion of the manifest URL embedded in the CWT.
 *
 * Body (optional, application/json):
 *   { "pin": "1234" }  ← required only if the VHL was issued with a PIN.
 *
 * Response 200:
 *   {
 *     "files": [
 *       { "contentType": "application/fhir+json", "location": "https://..." }
 *     ]
 *   }
 */
async function getManifestController(req, res, next) {
    try {
        const { manifestId } = req.params;
        const pin = req.body && typeof req.body.pin === 'string'
            ? req.body.pin.trim() || undefined
            : undefined;

        const manifest = getManifest(manifestId, pin);
        res.status(200).json(manifest);
    } catch (err) {
        next(err);
    }
}

/**
 * GET /vhl/document/:documentId
 *
 * Returns the AES-256-GCM encrypted IPS document.
 * Corresponds to Fase 4 step 8 in validar_qr_vhl.mmd:
 *   NodoDominio → NodoDominio_B: GET [Document_URL] (descarga P2P directa del archivo)
 *   NodoDominio_B → NodoDominio: 200 OK (retorna IPS encriptado)
 *
 * The caller decrypts with the symmetric key extracted from the CWT:
 *   Wire format: [ 12 bytes IV ][ N bytes ciphertext ][ 16 bytes GCM tag ]
 *   Algorithm:   AES-256-GCM
 *
 * Response 200: application/octet-stream (binary encrypted payload)
 */
async function getDocumentController(req, res, next) {
    try {
        const { documentId } = req.params;
        const payload = getDocument(documentId);
        res
            .status(200)
            .set('Content-Type', 'application/octet-stream')
            .send(payload);
    } catch (err) {
        next(err);
    }
}

module.exports = { getManifestController, getDocumentController };