from PyQt4.Qt import QMessageBox, QDialog, QVBoxLayout, QLabel
from binascii import unhexlify
from struct import pack
from sys import stderr

from gui.qt.password_dialog import make_password_dialog, run_password_dialog
from gui.qt.util import ok_cancel_buttons
from lib.account import BIP32_Account
from lib.bitcoin import EncodeBase58Check
from lib.i18n import _
from lib.plugins import BasePlugin
from lib.transaction import deserialize
from lib.wallet import NewWallet


try:
    import cmdtr
    from trezorlib.client import types
    from trezorlib.client import proto, BaseClient, ProtocolMixin
    from trezorlib.pinmatrix import PinMatrixWidget
    from trezorlib.transport import ConnectionError
    TREZOR = True
except: TREZOR = False

def log(msg):
    stderr.write("%s\n" % msg)
    stderr.flush()


class Plugin(BasePlugin):

    def fullname(self): return 'Trezor Wallet'

    def description(self): return 'Provides support for Trezor hardware wallet\n\nRequires github.com/trezor/python-trezor'

    def __init__(self, gui, name):
        BasePlugin.__init__(self, gui, name)
        self._is_available = self._init()

    def _init(self):
        return TREZOR

    def is_available(self):
        return self._is_available

    def enable(self):
        return BasePlugin.enable(self)

    def add_wallet_types(self, wallet_types):
        wallet_types.append(('trezor', _("Trezor wallet"), TrezorWallet))

    def installwizard_restore(self, wizard, storage):
        wallet = TrezorWallet(storage)
        wallet.create_accounts(None)
        return wallet

    def send_tx(self, tx, wallet):
        try:
            wallet.sign_transaction(tx, None, None)
        except Exception as e:
            tx.error = str(e)


class TrezorWallet(NewWallet):

    def __init__(self, storage):
        self.transport = None
        self.client = None

        NewWallet.__init__(self, storage)

        self.seed = 'trezor'
        
        self.storage.put('gap_limit', 20, False)    #obey BIP44 gap limit of 20

        self.use_encryption = False

        self.storage.put('seed', self.seed, False)
        self.storage.put('seed_version', self.seed_version, False)
        self.storage.put('use_encryption', self.use_encryption, False)

        self.device_checked = False

    def get_action(self):
        if not self.accounts:
            return 'create_accounts'

    def can_create_accounts(self):
        return True

    def is_watching_only(self):
        return False

    def default_account(self):
        return "44'/0'/0'"

    def get_client(self):
        if not TREZOR:
            raise Exception('please install github.com/trezor/python-trezor')

        if not self.client or self.client.bad:
            self.transport = cmdtr.get_transport('usb', '')
            self.client = QtGuiTrezorClient(self.transport)
            self.client.set_tx_api(self)
            #self.client.clear_session()# TODO Doesn't work with firmware 1.1, returns proto.Failure
            self.client.bad = False
            self.device_checked = False
            self.proper_device = False
        return self.client

    def account_id(self, i):
        return "44'/0'/%d'"%i

    def address_id(self, address):
        account_id, (change, address_index) = self.get_address_index(address)
        return "%s/%d/%d" % (account_id, change, address_index)

    def create_accounts(self, password):
        self.create_account('Main account', '') #name, empty password

    def make_account(self, account_id, password):
        xpub = self.get_public_key(account_id)
        self.add_master_public_key(account_id, xpub)
        account = BIP32_Account({'xpub':xpub})
        return account

    def get_public_key(self, bip32_path):
        address_n = self.get_client().expand_path(bip32_path)
        res = self.get_client().get_public_node(address_n)
        xpub = "0488B21E".decode('hex') + chr(res.depth) + self.i4b(res.fingerprint) + self.i4b(res.child_num) + res.chain_code + res.public_key
        return EncodeBase58Check(xpub)

    def get_master_public_key(self):
        if not self.mpk:
            self.mpk = self.get_public_key("44'/0'")
        return self.mpk

    def i4b(self, x):
        return pack('I', x)

    def add_keypairs(self, tx, keypairs, password):
        #do nothing - no priv keys available
        pass

    def sign_transaction(self, tx, keypairs, password):
        if tx.error or tx.is_complete():
            return

        if not self.check_proper_device():
            raise Exception('Wrong device or password')

        inputs = self.tx_inputs(tx)
        outputs = self.tx_outputs(tx)
        signed_tx = self.get_client().sign_tx('Bitcoin', inputs, outputs)[1]
        raw = signed_tx.encode('hex')
        tx.update(raw)

    def tx_inputs(self, tx):
        inputs = []

        for txinput in tx.inputs:
            txinputtype = types.TxInputType()
            address = txinput['address']
            try:
                address_path = self.address_id(address)
                address_n = self.get_client().expand_path(address_path)
                txinputtype.address_n.extend(address_n)
            except: pass

            if ('is_coinbase' in txinput and txinput['is_coinbase']):
                prev_hash = "\0"*32
                prev_index = 0xffffffff # signed int -1               
            else:        
                prev_hash = unhexlify(txinput['prevout_hash'])
                prev_index = txinput['prevout_n']

            txinputtype.prev_hash = prev_hash
            txinputtype.prev_index = prev_index

            if 'scriptSig' in txinput:
                script_sig = txinput['scriptSig']
                txinputtype.script_sig = script_sig

            if 'sequence' in txinput:
                sequence = txinput['sequence']
                txinputtype.sequence = sequence

            inputs.append(txinputtype)
            #TODO P2SH
        return inputs

    def tx_outputs(self, tx):
        outputs = []

        for type, address, amount in tx.outputs:
            txoutputtype = types.TxOutputType()

            if self.is_change(address):
                address_path = self.address_id(address)
                address_n = self.get_client().expand_path(address_path)
                txoutputtype.address_n.extend(address_n)
            else:
                txoutputtype.address = address

            txoutputtype.amount = amount

            txoutputtype.script_type = types.PAYTOADDRESS
            #TODO
            #if output['is_p2sh']:
            #    txoutputtype.script_type = types.PAYTOSCRIPTHASH

            outputs.append(txoutputtype)
        return outputs

    def electrum_tx_to_txtype(self, tx):
        t = types.TransactionType()
        d = deserialize(tx.raw)
        t.version = d['version']
        t.lock_time = d['lockTime']

        inputs = self.tx_inputs(tx)
        t.inputs.extend(inputs)

        for vout in d['outputs']:
            o = t.bin_outputs.add()
            o.amount = vout['value']
            o.script_pubkey = vout['scriptPubKey'].decode('hex')

        return t

    def get_tx(self, tx_hash):
        tx = self.transactions[tx_hash]
        return self.electrum_tx_to_txtype(tx)

    def check_proper_device(self):
        self.get_client().ping('t')
        if not self.device_checked:
            address = self.addresses(False, False)[0]
            address_id = self.address_id(address)
            n = self.get_client().expand_path(address_id)
            device_address = self.get_client().get_address('Bitcoin', n)
            self.device_checked = True

            if device_address != address:
                self.proper_device = False
            else:
                self.proper_device = True

        return self.proper_device


class TrezorQtGuiMixin(object):

    def __init__(self, *args, **kwargs):
        super(TrezorQtGuiMixin, self).__init__(*args, **kwargs)

    def callback_ButtonRequest(self, msg):
        i = QMessageBox.question(None, _('Trezor'), _("Please check request on Trezor's screen"), _('OK'), _('Cancel'))
        if i == 0:
            return proto.ButtonAck()
        return proto.Cancel()    

    def callback_PinMatrixRequest(self, msg):
        if msg.type == 1:
            desc = 'old PIN'
        elif msg.type == 2:
            desc = 'new PIN'
        elif msg.type == 3:
            desc = 'new PIN again'
        else:
            desc = 'PIN'

        pin = self.pin_dialog(msg="Please enter Trezor %s" % desc)
        if not pin:
            return proto.Cancel()
        return proto.PinMatrixAck(pin=pin)

    def callback_PassphraseRequest(self, msg):
        confirmed, p, passphrase = self.password_dialog()
        if not confirmed:
            QMessageBox.critical(None, _('Error'), _("Password request canceled"), _('OK'))
            return proto.Cancel()
        if passphrase is None:
            passphrase='' # Even blank string is valid Trezor passphrase
        return proto.PassphraseAck(passphrase=passphrase)

    def callback_WordRequest(self, msg):
        #TODO
        log("Enter one word of mnemonic: ")
        word = raw_input()
        return proto.WordAck(word=word)

    def password_dialog(self, msg=None):
        if not msg:
            msg = _("Please enter your Trezor password")

        d = QDialog()
        d.setModal(1)
        d.setLayout( make_password_dialog(d, None, msg, False) )
        return run_password_dialog(d, None, None)

    def pin_dialog(self, msg):
        d = QDialog(None)
        d.setModal(1)
        d.setWindowTitle(_("Enter PIN"))
        matrix = PinMatrixWidget()

        vbox = QVBoxLayout()
        vbox.addWidget(QLabel(msg))
        vbox.addWidget(matrix)
        vbox.addLayout(ok_cancel_buttons(d))
        d.setLayout(vbox)

        if not d.exec_(): return
        return str(matrix.get_value())

if TREZOR:
    class QtGuiTrezorClient(ProtocolMixin, TrezorQtGuiMixin, BaseClient):
        def call_raw(self, msg):
            try:
                resp = BaseClient.call_raw(self, msg)
            except ConnectionError:
                self.bad = True
                raise
    
            return resp