'use strict';

var rlp = require('rlp');

var Contract = require('./contract.js');
var SigningKey = require('./signing-key.js');

var utils = require('./utils.js');


var transactionFields = [
    {name: 'nonce',    maxLength: 32, },
    {name: 'gasPrice', maxLength: 32, },
    {name: 'gasLimit', maxLength: 32, },
    {name: 'to',          length: 20, },
    {name: 'value',    maxLength: 32, },
    {name: 'data'},
];

function Wallet(privateKey) {
    if (!(this instanceof Wallet)) { throw new Error('missing new'); }

    // Make sure we have a valid signing key
    var signingKey = privateKey;
    if (!(privateKey instanceof SigningKey)) {
        signingKey = new SigningKey(privateKey);
    }
    utils.defineProperty(this, 'privateKey', signingKey.privateKey);

    utils.defineProperty(this, 'address', signingKey.address);

    utils.defineProperty(this, 'sign', function(transaction) {
        var raw = [];
        transactionFields.forEach(function(fieldInfo) {
            var value = transaction[fieldInfo.name] || (new Buffer(0));
            value = utils.hexOrBuffer(utils.hexlify(value), fieldInfo.name);

            // Fixed-width field
            if (fieldInfo.length && value.length !== fieldInfo.length) {
                var error = new Error('invalid ' + fieldInfo.name);
                error.reason = 'wrong length';
                error.value = value;
                throw error;
            }

            // Variable-width (with a maximum)
            if (fieldInfo.maxLength) {
                value = utils.stripZeros(value);
                if (value.length > fieldInfo.maxLength) {
                    var error = new Error('invalid ' + fieldInfo.name);
                    error.reason = 'too long';
                    error.value = value;
                    throw error;
                }
            }

            raw.push(value);
        });

        var digest = utils.sha3(rlp.encode(raw));

        var signature = signingKey.signDigest(digest);
        var s = signature.s;
        var v = signature.recoveryParam;

        raw.push(new Buffer([27 + v]));
        raw.push(utils.bnToBuffer(signature.r));
        raw.push(utils.bnToBuffer(s));

        return ('0x' + rlp.encode(raw).toString('hex'));
    });
}

utils.defineProperty(Wallet, 'getAddress', SigningKey.getAddress);
utils.defineProperty(Wallet, 'getIcapAddress', SigningKey.getIcapAddress);

utils.defineProperty(Wallet, '_Contract', Contract);


utils.defineProperty(Wallet.prototype, 'getContract', function(address, abi, web3) {
    return new Contract(web3, this, address, new Contract.Interface(abi));
});

module.exports = Wallet;