var nb = require("buffa");
var openpgp = require("openpgp");


function cleanpgpstring(astr) {
    var str = astr.trim();
    str = str.replace(/\r/g, "\n");
    str = str.replace(/\n\n/g, "\n");
    var a = str.split("\n");
    a = a.filter(function(aa) {
        return !(aa.indexOf("Version") > -1 || aa.indexOf("Comment") > -1)
    })
    str = a.join("\n");
    return str;
}

function makeloginstr(str) {

    return nb(cleanpgpstring(str)).toBase(54);
}



function create_identity(opt) {
    var options = Object.assign({
        "passphrase": "",
        "numBits": 1024,
        "userIds": {
            "name": "user",
            "email": ""
        }

    }, opt)



    var oper = openpgp.generateKey(options)
        .then(
            function(keya) {
                keya.publickey = makeloginstr(keya.publicKeyArmored)
                keya.sid = nb(keya.publickey).SHA1().toBase(36);
                var kkk = {
                    "secured": false,
                    "sid": keya.sid,
                    "publickey": keya.publickey,
                    privatekey: makeloginstr(keya.privateKeyArmored),
                    "options": options
                }
                if (keya.key.primaryKey.encrypted) {
                    kkk.secured = true;
                }
                kkk.key = keya.key;
                return kkk;
            })
    return oper;
}

function encrypt_object_to(keystr, obj, cb) {
    var keyen = openpgp.key.readArmored(nb(keystr, 54).toString());
    var key = keyen.keys[0];
    var options = {
        data: JSON.stringify(obj, true, 2), // input as String (or Uint8Array)
        publicKeys: key, // for encryption
    };
    openpgp.encrypt(options).then(function(ciphertext) {
        var encrypted = nb(cleanpgpstring(ciphertext.data)).toBase(59); // '-----BEGIN PGP MESSAGE ... END PGP MESSAGE-----'
        cb(encrypted);
    });
}

function decrypt_object_to(keystr, objstr, cb, passphrase) {
    var keyen = openpgp.key.readArmored(nb(keystr, 54).toString());
    var key = keyen.keys[0];
    if (passphrase) {
        key.decrypt(passphrase)
    } else {
        key.decrypt(prompt("passphrase"))
    }

    var options = {
        message: openpgp.message.readArmored(nb(objstr, 59).toString()), // parse armored message
        privateKey: key // for decryption
    };
    openpgp.decrypt(options).then(function(plaintext) {
        var decrypted = JSON.parse(plaintext.data)
        cb(decrypted);
    })

}


module.exports = {
    decrypt_object_to: decrypt_object_to,
    encrypt_object_to: encrypt_object_to,
    create_identity: create_identity,
    makeloginstr: makeloginstr,
    cleanpgpstring: cleanpgpstring,
    openpgp: openpgp
}