#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
    Blockstack
    ~~~~~
    copyright: (c) 2014-2015 by Halfmoon Labs, Inc.
    copyright: (c) 2016 by Blockstack.org

    This file is part of Blockstack

    Blockstack 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.

    Blockstack 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 Blockstack. If not, see <http://www.gnu.org/licenses/>.
"""

from utilitybelt import is_hex, is_valid_int
from binascii import hexlify, unhexlify
from virtualchain import BitcoinPrivateKey, BitcoinPublicKey
from pybitcoin import script_to_hex, make_pay_to_address_script
from pybitcoin.transactions.outputs import calculate_change_amount

import virtualchain
log = virtualchain.get_logger("blockstack-server")

import bitcoin
import json

try:
    from .config import *
    from .b40 import *
except:
    # hack around relative paths
    import sys 
    import os
    sys.path.append(os.path.dirname(__file__))
    from config import *
    from b40 import *


def is_name_valid( fqn ):
    """
    Is a fully-qualified name acceptable?
    Return True if so
    Return False if not

    TODO: DRY up; use client
    """

    if fqn.count( "." ) != 1:
        return False

    name, namespace_id = fqn.split(".")

    if len(name) == 0 or len(namespace_id) == 0:
        return False 

    if not is_b40( name ) or "+" in name or "." in name:
        return False 

    if not is_b40( namespace_id ) or "+" in namespace_id or "." in namespace_id:
        return False
    
    name_hex = hexlify(name)
    if len(name_hex) > LENGTHS['blockchain_id_name'] * 2:
       # too long
       return False 

    return True


def is_namespace_valid( namespace_id ):
    """
    Is a namespace ID valid?

    TODO: DRY up; use client
    """
    if not is_b40( namespace_id ) or "+" in namespace_id or namespace_id.count(".") > 0:
        return False

    if len(namespace_id) == 0 or len(namespace_id) > LENGTHS['blockchain_id_namespace_id']:
        return False

    return True