'use strict';

//var crypto = require('crypto');
var forge = require('node-forge');

function binstrToB64(binstr) {
  return new Buffer(binstr, 'binary').toString('base64');
}
function b64ToBinstr(b64) {
  return new Buffer(b64, 'b64').toString('binary');
}

/*
  importPemPrivateKey: function(pem) {
    var key = forge.pki.privateKeyFromPem(pem);
    return {
      privateKey: exportPrivateKey(key),
      publicKey: exportPublicKey(key)
    };
  },

  importPemCertificate: function(pem) {
    return forge.pki.certificateFromPem(pem);
  },

  privateKeyToPem: function(privateKey) {
    var priv = importPrivateKey(privateKey);
    return forge.pki.privateKeyToPem(priv);
  },

  certificateToPem: function(certificate) {
    var derCert = base64ToBytes(certificate);
    var cert = forge.pki.certificateFromAsn1(forge.asn1.fromDer(derCert));
    return forge.pki.certificateToPem(cert);
  },
*/

var extrac = module.exports = {
  //
  // internals
  //
  _forgeToPrivateJwk: function (keypair) {
    var k = keypair._forge;

    return {
      kty: "RSA"
    , n: binstrToB64(k.n.toByteArray())
    , e: binstrToB64(k.e.toByteArray())
    , d: binstrToB64(k.d.toByteArray())
    , p: binstrToB64(k.p.toByteArray())
    , q: binstrToB64(k.q.toByteArray())
    , dp: binstrToB64(k.dP.toByteArray())
    , dq: binstrToB64(k.dQ.toByteArray())
    , qi: binstrToB64(k.qInv.toByteArray())
    };
  }
, _forgeToPublicJwk: function (keypair) {
    var k = keypair._forge || keypair._forgePublic;
    return {
      kty: "RSA"
    , n: binstrToB64(k.n.toByteArray())
    , e: binstrToB64(k.e.toByteArray())
    };
  }



  //
  // Import Forge
  //
, _forgeImportJwk: require('./rsa-forge')._forgeImportJwk
, _forgeImportPublicJwk: require('./rsa-forge')._forgeImportPublicJwk
, _forgeImportPem: function (keypair) {
    keypair._forge = keypair._forge || forge.pki.privateKeyFromPem(keypair.privateKeyPem);
  }
, _forgeImportPublicPem: function (keypair) {
    keypair._forgePublic = keypair._forgePublic || forge.pki.publicKeyFromPem(keypair.publicKeyPem);
  }
, importForge: function (keypair) {
    extrac._forgeImportJwk(keypair);
    if (keypair.privateKeyPem) {
      extrac._forgeImportPem(keypair);
    }
    if (keypair.publicKeyPem) {
      extrac._forgeImportPublicPem(keypair);
    }
    return keypair;
  }



  //
  // Export JWK
  //
, exportPrivateJwk: function (keypair) {
    var hasUrsaPrivate = keypair._ursa && true;
    var hasPrivatePem = keypair.privateKeyPem && true;
    var hasForgePrivate = keypair._forge && keypair._forge && true;

    if (keypair.privateKeyJwk) {
      return keypair.privateKeyJwk;
    }

    if (!hasForgePrivate) {
      if (hasUrsaPrivate && !hasPrivatePem) {
        keypair.privateKeyPem = keypair._ursa.toPrivatePem().toString('ascii');
      }

      if (keypair.privateKeyPem) {
        extrac._forgeImportPem(keypair);
      }
    }

    if (keypair._forge && keypair._forge) {
      return extrac._forgeToPrivateJwk(keypair);
    }

    throw new Error("None of privateKeyPem, _ursa, _forge, or privateKeyJwk found. No way to export private key Jwk");
  }
, exportPublicJwk: function (keypair) {
    var hasUrsaPublic = (keypair._ursa || keypair._ursaPublic) && true;
    var hasPublicPem = (keypair.privateKeyPem || keypair.publicKeyPem) && true;
    var hasForgePublic = keypair._forge && true;

    if (keypair.publicKeyJwk) {
      return keypair.publicKeyJwk;
    }

    if (keypair.privateKeyJwk) {
      return {
        kty: 'RSA'
      , n: keypair.privateKeyJwk.n
      , e: keypair.privateKeyJwk.e
      };
    }

    if (!hasForgePublic) {
      if (hasUrsaPublic && !hasPublicPem) {
        keypair.publicKeyPem = (keypair._ursa || keypair._ursaPublic).toPublicPem().toString('ascii');
      }

      if (keypair.publicKeyPem) {
        extrac._forgeImportPublicPem(keypair);
      }
    }

    if (keypair._forge && keypair._forge) {
      return extrac._forgeToPublicJwk(keypair);
    }

    throw new Error("None of publicKeyPem privateKeyPem, _ursa, _forge, publicKeyJwk, or privateKeyJwk found. No way to export private key Jwk");
  }



};