#!/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/words/brain 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

Transactions with either mmgen or non-mmgen input addresses may be signed.
For non-mmgen inputs, the bitcoind wallet.dat is used as the key source.
For mmgen inputs, key data is generated from your seed as with the
mmgen-addrgen and mmgen-keygen utilities.

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.

In cases of transactions with mixed mmgen and non-mmgen inputs, non-mmgen
keys must be supplied in a separate file (WIF format, one key per line)
using the '--keys-from-file' option.  Alternatively, one may import the
required mmgen keys into the bitcoind wallet.dat and use the
'--force-wallet-dat' option.

Seed data supplied in files must have the following extensions:
   wallet:      '.{}'
   seed:        '.{}'
   mnemonic:    '.{}'
   brainwallet: '.{}'
""".format(seed_ext,wallet_ext,seed_ext,mn_ext,brain_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) > 0:
	for i in cmd_args: check_infile(i)
else: usage(help_data)

# Begin execution

c = connect_to_bitcoind()

tx_file = cmd_args.pop(0)
tx_data = get_lines_from_file(tx_file,"transaction data")

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

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

if not 'quiet' 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)

# Are inputs mmgen addresses?
mmgen_addrs,other_addrs,keys = [],[],[]

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

if mmgen_addrs and not 'force_wallet_dat' in opts:
	# Check that all the seed IDs are the same:
	seed_ids = list(set([i['account'][:8] for i in mmgen_addrs]))
	while seed_ids:
		infile = False
		if cmd_args:
			infile = cmd_args.pop()
			ext = infile.split(".")[-1]
			found = False
			for e,o in (
				(wallet_ext, {}),
				(mn_ext,     {"from_mnemonic":True}),
				(seed_ext,   {"from_seed":    True}),
				(brain_ext,  {})
			):
				if e == ext:
					found = True
					if e == brain_ext:
						if "from_brain" in opts: o = opts
						else:
							msg("'--from-brain' option must be specified for brainwallet file")
							sys.exit(2)
					silent = False
					while True:
						seed = get_seed(infile,o,silent=silent)
						silent = True
						if seed: break

			if not found:
				msg("%s: invalid file extension" % ext)
				sys.exit(2)

		elif "from_brain" in opts or "from_mnemonic" in opts or "from_seed" in opts:
			msg("Need data for seed ID %s" % seed_ids[0])
			silent = False
			while True:
				seed = get_seed("",opts,silent=silent)
				silent = True
				if seed: break
		else:
			msg("One of '-b', '-m' or '-s' must be specified for seed IDs: %s" %
					" ".join(seed_ids))
			sys.exit(2)

		seed_id = make_chksum_8(seed)
		if seed_id in seed_ids:
			seed_ids.remove(seed_id)
			seed_id_addrs = []
			for i in mmgen_addrs:
				if i['account'][:8] == seed_id:
					seed_id_addrs.append(int(i['account'].split()[0][9:]))

			from mmgen.addr import generate_addrs
			o = {'no_addresses': True, 'gen_what': "keys"}
			keys += [i['wif'] for i in generate_addrs(seed, seed_id_addrs, o)]
		else:
			msg("Supplied seed ID (%s) is incorrect" % seed_id)
			if infile:
				msg("Invalid input file: %s" % infile)
				sys.exit(2)

	if other_addrs:
		if 'keys_from_file' in opts:
			keys += get_lines_from_file(opts['keys_from_file'],
					"additional key data")
		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)

	sig_tx = sign_transaction(c,tx_hex,sig_data,keys)

elif 'keys_from_file' in opts:
	keys = get_lines_from_file(opts['keys_from_file'],"key data")

	sig_tx = sign_transaction(c,tx_hex,sig_data,keys)
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")

	sig_tx = sign_transaction(c,tx_hex,sig_data)

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

if sig_tx['complete']:
	msg("Signing completed")
else:
	msg("Some keys were missing.  Transaction could not be signed.")
	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)