#!/usr/bin/env python
#
# mmgen = Multi-Mode GENerator, command-line Bitcoin cold storage solution
# Copyright (C) 2013 by philemon <mmgen-py@yandex.com>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
"""
mmgen-txsign: Sign a Bitcoin transaction generated by mmgen-txcreate
"""

import sys
#from hashlib import sha256

from mmgen.Opts import *
from mmgen.license import *
from mmgen.config import *
from mmgen.tx import *
from mmgen.utils import *

help_data = {
	'prog_name': sys.argv[0].split("/")[-1],
	'desc':    "Sign a Bitcoin transaction generated by mmgen-txcreate",
	'usage':   "[opts] <transaction file> [mmgen wallet/seed/mnemonic file]",
	'options': """
-h, --help               Print this help message
-d, --outdir          d  Specify an alternate directory 'd' for output
-e, --echo-passphrase    Print passphrase to screen when typing it
-f, --force-wallet-dat   Force the use of wallet.dat as a key source
-i, --info               Display information about the transaction and exit
-k, --keys-from-file  k  Provide additional key data from file 'k'
-q, --quiet              Suppress warnings; overwrite files without asking

-b, --from-brain     l,p Generate keys from a user-created password,
                         i.e. a "brainwallet", using seed length 'l' and
                         hash preset 'p' (comma-separated)
-m, --from-mnemonic      Generate keys from an electrum-like mnemonic
-s, --from-seed          Generate keys from a seed in .{} format

Data for the --from-<what> options will be taken from a file if a second
file is specified on the command line.  Otherwise, the user will be
prompted to enter the data.
""".format(seed_ext)
}

short_opts = "hd:efik:qb:ms"
long_opts  = "help","outdir=","echo_passphrase","force_wallet_dat","info",\
		  "keys_from_file=","quiet","from_brain=","from_mnemonic","from_seed"

opts,cmd_args = process_opts(sys.argv,help_data,short_opts,long_opts)

# Exits on invalid input
check_opts(opts, ('outdir','from_brain'))
if 'keys_from_file' in opts: check_infile(opts['keys_from_file'])

if debug:
	print "Processed options:     %s" % repr(opts)
	print "Cmd args:              %s" % repr(cmd_args)

if len(cmd_args) in (1,2):
	tx_file = cmd_args[0]
	check_infile(tx_file)
else: usage(help_data)

# Begin execution

c = connect_to_bitcoind()

tx_data = get_lines_from_file(tx_file,"transaction data")

metadata,tx_hex,sig_data,inputs_data = parse_tx_data(tx_data,tx_file)

# Are inputs mmgen addresses?
infile,mmgen_addrs,other_addrs = "",[],[]
# Check that all the seed IDs are the same:

for i in inputs_data:
	if verify_mmgen_label(i['account']):
		mmgen_addrs.append(i)
	else:
		other_addrs.append(i)

if mmgen_addrs:
	a_ids = list(set([i['account'][:8] for i in mmgen_addrs]))
	if len(a_ids) != 1:
		msg("Addresses come from different seeds! (%s)" % " ".join(a_ids))
		sys.exit(3)

	if len(cmd_args) == 2:
		infile = cmd_args[1]
	else:
		if "from_brain" in opts \
			or "from_mnemonic" in opts \
				or "from_seed" in opts:
			infile = ""
		else:
			msg("Inputs contain mmgen addresses.  An MMGen wallet file must be specified on the command line (or use the '-b', '-m' or '-s' options).".strip())
			sys.exit(2)

	if other_addrs:
		if 'keys_from_file' in opts:
			add_keys = get_lines_from_file(opts['keys_from_file'])
		else:
			msg("""
A key file must be supplied (option '-f') for the following non-mmgen
address%s: %s""" % (
	"" if len(other_addrs) == 1 else "es",
	" ".join([i['address'] for i in other_addrs])
	  ))
			sys.exit(2)

if 'info' in opts:
	view_tx_data(c,inputs_data,tx_hex,metadata)
	sys.exit(0)

if not 'quiet' in opts and not 'info' in opts: do_license_msg()

msg("Successfully opened transaction file '%s'" % tx_file)

if user_confirm("View transaction data? ",default_yes=False):
	view_tx_data(c,inputs_data,tx_hex,metadata)

if mmgen_addrs:
	seed    = get_seed(infile,opts)
	seed_id = make_chksum_8(seed)

	if seed_id != a_ids[0]:
		msg("Seed ID of wallet (%s) doesn't match that of addresses (%s)"
				% (seed_id,a_ids[0]))
		sys.exit(3)
	addr_nums = [int(i['account'].split()[0][9:]) for i in mmgen_addrs]
	from mmgen.addr import generate_addrs
	o = {'no_addresses': True, 'gen_what': "keys"}
	keys = [i['wif'] for i in generate_addrs(seed, addr_nums, o)]
	if other_addrs: keys += add_keys
	try:
		sig_tx = c.signrawtransaction(tx_hex,sig_data,keys)
	except:
		msg("Failed to sign transaction")
		sys.exit(3)
else:
	prompt = "Enter passphrase for bitcoind wallet: "
	if 'echo_passphrase' in opts:
		password = my_raw_input(prompt)
	else:
		password = my_getpass(prompt)

	wallet_enc = True
	from mmgen.rpc import exceptions

	try:
		c.walletpassphrase(password, 9999)
	except exceptions.WalletWrongEncState:
		msg("Wallet is unencrypted")
		wallet_enc = False
	except exceptions.WalletPassphraseIncorrect:
		msg("Passphrase incorrect")
		sys.exit(3)
	except exceptions.WalletAlreadyUnlocked:
		msg("WARNING: Wallet already unlocked!")
	else:
		msg("Passphrase OK")

	try:
		sig_tx = c.signrawtransaction(tx_hex,sig_data)
	except:
		msg("Failed to sign transaction")
		if wallet_enc:
			c.walletlock()
			msg("Locking wallet")
		sys.exit(3)

	if wallet_enc:
		c.walletlock()
		msg("Locking wallet")

if sig_tx['complete']:
	msg("Signing completed")
else:
	msg("Signing failed: 'complete=%s'" % sig_tx['complete'])
	sys.exit(3)

prompt = "Save signed transaction?"
if user_confirm(prompt,default_yes=True):
	print_signed_tx_to_file(tx_hex,sig_tx['hex'],metadata,opts)