// Copyright (c) 2011-2013 The Bitcoin developers
// Distributed under the MIT/X11 software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#include "walletmodel.h"

#include "addresstablemodel.h"
#include "guiconstants.h"
#include "transactiontablemodel.h"

#include "base58.h"
#include "db.h"
#include "keystore.h"
#include "main.h"
#include "sync.h"
#include "ui_interface.h"
#include "wallet.h"
#include "walletdb.h" // for BackupWallet

#include <stdint.h>

#include <QDebug>
#include <QSet>
#include <QTimer>

WalletModel::WalletModel(CWallet *wallet, OptionsModel *optionsModel, QObject *parent) :
    QObject(parent), wallet(wallet), optionsModel(optionsModel), addressTableModel(0),
    transactionTableModel(0),
    cachedBalance(0), cachedUnconfirmedBalance(0), cachedImmatureBalance(0),
    cachedNumTransactions(0),
    cachedEncryptionStatus(Unencrypted),
    cachedNumBlocks(0)
{
    addressTableModel = new AddressTableModel(wallet, this);
    transactionTableModel = new TransactionTableModel(wallet, this);

    // This timer will be fired repeatedly to update the balance
    pollTimer = new QTimer(this);
    connect(pollTimer, SIGNAL(timeout()), this, SLOT(pollBalanceChanged()));
    pollTimer->start(MODEL_UPDATE_DELAY);

    subscribeToCoreSignals();
}

WalletModel::~WalletModel()
{
    unsubscribeFromCoreSignals();
}

qint64 WalletModel::getBalance() const
{
    return wallet->GetBalance();
}

qint64 WalletModel::getUnconfirmedBalance() const
{
    return wallet->GetUnconfirmedBalance();
}

qint64 WalletModel::getImmatureBalance() const
{
    return wallet->GetImmatureBalance();
}

int WalletModel::getNumTransactions() const
{
    int numTransactions = 0;
    {
        LOCK(wallet->cs_wallet);
        // the size of mapWallet contains the number of unique transaction IDs
        // (e.g. payments to yourself generate 2 transactions, but both share the same transaction ID)
        numTransactions = wallet->mapWallet.size();
    }
    return numTransactions;
}

void WalletModel::updateStatus()
{
    EncryptionStatus newEncryptionStatus = getEncryptionStatus();

    if(cachedEncryptionStatus != newEncryptionStatus)
        emit encryptionStatusChanged(newEncryptionStatus);
}

void WalletModel::pollBalanceChanged()
{
    if(chainActive.Height() != cachedNumBlocks)
    {
        // Balance and number of transactions might have changed
        cachedNumBlocks = chainActive.Height();
        checkBalanceChanged();
    }
}

void WalletModel::checkBalanceChanged()
{
    qint64 newBalance = getBalance();
    qint64 newUnconfirmedBalance = getUnconfirmedBalance();
    qint64 newImmatureBalance = getImmatureBalance();

    if(cachedBalance != newBalance || cachedUnconfirmedBalance != newUnconfirmedBalance || cachedImmatureBalance != newImmatureBalance)
    {
        cachedBalance = newBalance;
        cachedUnconfirmedBalance = newUnconfirmedBalance;
        cachedImmatureBalance = newImmatureBalance;
        emit balanceChanged(newBalance, newUnconfirmedBalance, newImmatureBalance);
    }
}

void WalletModel::updateTransaction(const QString &hash, int status)
{
    if(transactionTableModel)
        transactionTableModel->updateTransaction(hash, status);

    // Balance and number of transactions might have changed
    checkBalanceChanged();

    int newNumTransactions = getNumTransactions();
    if(cachedNumTransactions != newNumTransactions)
    {
        cachedNumTransactions = newNumTransactions;
        emit numTransactionsChanged(newNumTransactions);
    }
}

void WalletModel::updateAddressBook(const QString &address, const QString &label,
        bool isMine, const QString &purpose, int status)
{
    if(addressTableModel)
        addressTableModel->updateEntry(address, label, isMine, purpose, status);
}

bool WalletModel::validateAddress(const QString &address)
{
    CBitcoinAddress addressParsed(address.toStdString());
    return addressParsed.IsValid();
}

WalletModel::SendCoinsReturn WalletModel::prepareTransaction(WalletModelTransaction &transaction)
{
    qint64 total = 0;
    QList<SendCoinsRecipient> recipients = transaction.getRecipients();
    std::vector<std::pair<CScript, int64_t> > vecSend;

    if(recipients.empty())
    {
        return OK;
    }

    QSet<QString> setAddress; // Used to detect duplicates
    int nAddresses = 0;

    // Pre-check input data for validity
    foreach(const SendCoinsRecipient &rcp, recipients)
    {
        if (rcp.paymentRequest.IsInitialized())
        {   // PaymentRequest...
            int64_t subtotal = 0;
            const payments::PaymentDetails& details = rcp.paymentRequest.getDetails();
            for (int i = 0; i < details.outputs_size(); i++)
            {
                const payments::Output& out = details.outputs(i);
                if (out.amount() <= 0) continue;
                subtotal += out.amount();
                const unsigned char* scriptStr = (const unsigned char*)out.script().data();
                CScript scriptPubKey(scriptStr, scriptStr+out.script().size());
                vecSend.push_back(std::pair<CScript, int64_t>(scriptPubKey, out.amount()));
            }
            if (subtotal <= 0)
            {
                return InvalidAmount;
            }
            total += subtotal;
        }
        else
        {   // User-entered bitcoin address / amount:
            if(!validateAddress(rcp.address))
            {
                return InvalidAddress;
            }
            if(rcp.amount <= 0)
            {
                return InvalidAmount;
            }
            setAddress.insert(rcp.address);
            ++nAddresses;

            CScript scriptPubKey;
            scriptPubKey.SetDestination(CBitcoinAddress(rcp.address.toStdString()).Get());
            vecSend.push_back(std::pair<CScript, int64_t>(scriptPubKey, rcp.amount));

            total += rcp.amount;
        }
    }
    if(setAddress.size() != nAddresses)
    {
        return DuplicateAddress;
    }

    if(total > getBalance())
    {
        return AmountExceedsBalance;
    }

    if((total + nTransactionFee) > getBalance())
    {
        transaction.setTransactionFee(nTransactionFee);
        return SendCoinsReturn(AmountWithFeeExceedsBalance);
    }

    {
        LOCK2(cs_main, wallet->cs_wallet);

        transaction.newPossibleKeyChange(wallet);
        int64_t nFeeRequired = 0;
        std::string strFailReason;

        CWalletTx *newTx = transaction.getTransaction();
        CReserveKey *keyChange = transaction.getPossibleKeyChange();
        bool fCreated = wallet->CreateTransaction(vecSend, *newTx, *keyChange, nFeeRequired, strFailReason);
        transaction.setTransactionFee(nFeeRequired);

        if(!fCreated)
        {
            if((total + nFeeRequired) > wallet->GetBalance())
            {
                return SendCoinsReturn(AmountWithFeeExceedsBalance);
            }
            emit message(tr("Send Coins"), QString::fromStdString(strFailReason),
                         CClientUIInterface::MSG_ERROR);
            return TransactionCreationFailed;
        }
    }

    return SendCoinsReturn(OK);
}

WalletModel::SendCoinsReturn WalletModel::sendCoins(WalletModelTransaction &transaction)
{
    QByteArray transaction_array; /* store serialized transaction */

    {
        LOCK2(cs_main, wallet->cs_wallet);
        CWalletTx *newTx = transaction.getTransaction();

        // Store PaymentRequests in wtx.vOrderForm in wallet.
        foreach(const SendCoinsRecipient &rcp, transaction.getRecipients())
        {
            if (rcp.paymentRequest.IsInitialized())
            {
                std::string key("PaymentRequest");
                std::string value;
                rcp.paymentRequest.SerializeToString(&value);
                newTx->vOrderForm.push_back(make_pair(key, value));
            }
        }

        CReserveKey *keyChange = transaction.getPossibleKeyChange();
        if(!wallet->CommitTransaction(*newTx, *keyChange))
            return TransactionCommitFailed;

        CTransaction* t = (CTransaction*)newTx;
        CDataStream ssTx(SER_NETWORK, PROTOCOL_VERSION);
        ssTx << *t;
        transaction_array.append(&(ssTx[0]), ssTx.size());
    }

    // Add addresses / update labels that we've sent to to the address book,
    // and emit coinsSent signal for each recipient
    foreach(const SendCoinsRecipient &rcp, transaction.getRecipients())
    {
        // Don't touch the address book when we have a payment request
        if (!rcp.paymentRequest.IsInitialized())
        {
            std::string strAddress = rcp.address.toStdString();
            CTxDestination dest = CBitcoinAddress(strAddress).Get();
            std::string strLabel = rcp.label.toStdString();
            {
                LOCK(wallet->cs_wallet);

                std::map<CTxDestination, CAddressBookData>::iterator mi = wallet->mapAddressBook.find(dest);

                // Check if we have a new address or an updated label
                if (mi == wallet->mapAddressBook.end())
                {
                    wallet->SetAddressBook(dest, strLabel, "send");
                }
                else if (mi->second.name != strLabel)
                {
                    wallet->SetAddressBook(dest, strLabel, ""); // "" means don't change purpose
                }
            }
        }
        emit coinsSent(wallet, rcp, transaction_array);
    }

    return SendCoinsReturn(OK);
}

OptionsModel *WalletModel::getOptionsModel()
{
    return optionsModel;
}

AddressTableModel *WalletModel::getAddressTableModel()
{
    return addressTableModel;
}

TransactionTableModel *WalletModel::getTransactionTableModel()
{
    return transactionTableModel;
}

WalletModel::EncryptionStatus WalletModel::getEncryptionStatus() const
{
    if(!wallet->IsCrypted())
    {
        return Unencrypted;
    }
    else if(wallet->IsLocked())
    {
        return Locked;
    }
    else
    {
        return Unlocked;
    }
}

bool WalletModel::setWalletEncrypted(bool encrypted, const SecureString &passphrase)
{
    if(encrypted)
    {
        // Encrypt
        return wallet->EncryptWallet(passphrase);
    }
    else
    {
        // Decrypt -- TODO; not supported yet
        return false;
    }
}

bool WalletModel::setWalletLocked(bool locked, const SecureString &passPhrase)
{
    if(locked)
    {
        // Lock
        return wallet->Lock();
    }
    else
    {
        // Unlock
        return wallet->Unlock(passPhrase);
    }
}

bool WalletModel::changePassphrase(const SecureString &oldPass, const SecureString &newPass)
{
    bool retval;
    {
        LOCK(wallet->cs_wallet);
        wallet->Lock(); // Make sure wallet is locked before attempting pass change
        retval = wallet->ChangeWalletPassphrase(oldPass, newPass);
    }
    return retval;
}

bool WalletModel::backupWallet(const QString &filename)
{
    return BackupWallet(*wallet, filename.toLocal8Bit().data());
}

// Handlers for core signals
static void NotifyKeyStoreStatusChanged(WalletModel *walletmodel, CCryptoKeyStore *wallet)
{
    qDebug() << "NotifyKeyStoreStatusChanged";
    QMetaObject::invokeMethod(walletmodel, "updateStatus", Qt::QueuedConnection);
}

static void NotifyAddressBookChanged(WalletModel *walletmodel, CWallet *wallet,
        const CTxDestination &address, const std::string &label, bool isMine,
        const std::string &purpose, ChangeType status)
{
    QString strAddress = QString::fromStdString(CBitcoinAddress(address).ToString());
    QString strLabel = QString::fromStdString(label);
    QString strPurpose = QString::fromStdString(purpose);

    qDebug() << "NotifyAddressBookChanged : " + strAddress + " " + strLabel + " isMine=" + QString::number(isMine) + " purpose=" + strPurpose + " status=" + QString::number(status);
    QMetaObject::invokeMethod(walletmodel, "updateAddressBook", Qt::QueuedConnection,
                              Q_ARG(QString, strAddress),
                              Q_ARG(QString, strLabel),
                              Q_ARG(bool, isMine),
                              Q_ARG(QString, strPurpose),
                              Q_ARG(int, status));
}

static void NotifyTransactionChanged(WalletModel *walletmodel, CWallet *wallet, const uint256 &hash, ChangeType status)
{
    QString strHash = QString::fromStdString(hash.GetHex());

    qDebug() << "NotifyTransactionChanged : " + strHash + " status= " + QString::number(status);
    QMetaObject::invokeMethod(walletmodel, "updateTransaction", Qt::QueuedConnection,
                              Q_ARG(QString, strHash),
                              Q_ARG(int, status));
}

void WalletModel::subscribeToCoreSignals()
{
    // Connect signals to wallet
    wallet->NotifyStatusChanged.connect(boost::bind(&NotifyKeyStoreStatusChanged, this, _1));
    wallet->NotifyAddressBookChanged.connect(boost::bind(NotifyAddressBookChanged, this, _1, _2, _3, _4, _5, _6));
    wallet->NotifyTransactionChanged.connect(boost::bind(NotifyTransactionChanged, this, _1, _2, _3));
}

void WalletModel::unsubscribeFromCoreSignals()
{
    // Disconnect signals from wallet
    wallet->NotifyStatusChanged.disconnect(boost::bind(&NotifyKeyStoreStatusChanged, this, _1));
    wallet->NotifyAddressBookChanged.disconnect(boost::bind(NotifyAddressBookChanged, this, _1, _2, _3, _4, _5, _6));
    wallet->NotifyTransactionChanged.disconnect(boost::bind(NotifyTransactionChanged, this, _1, _2, _3));
}

// WalletModel::UnlockContext implementation
WalletModel::UnlockContext WalletModel::requestUnlock()
{
    bool was_locked = getEncryptionStatus() == Locked;
    if(was_locked)
    {
        // Request UI to unlock wallet
        emit requireUnlock();
    }
    // If wallet is still locked, unlock was failed or cancelled, mark context as invalid
    bool valid = getEncryptionStatus() != Locked;

    return UnlockContext(this, valid, was_locked);
}

WalletModel::UnlockContext::UnlockContext(WalletModel *wallet, bool valid, bool relock):
        wallet(wallet),
        valid(valid),
        relock(relock)
{
}

WalletModel::UnlockContext::~UnlockContext()
{
    if(valid && relock)
    {
        wallet->setWalletLocked(true);
    }
}

void WalletModel::UnlockContext::CopyFrom(const UnlockContext& rhs)
{
    // Transfer context; old object no longer relocks wallet
    *this = rhs;
    rhs.relock = false;
}