# -*- coding: utf-8 -*-

import datetime
import json
import os
import sys

# for network
import socket
import fcntl
import struct
import array
import urllib


class Common:
    def load_config(self):
        self.settings_node = self.settings_node()
        self.settings_vm = self.settings_vm()

    def time(self):
        """
        используется для вывода времени на экран в консоли
        """
        return str(datetime.datetime.now())

    def error(self, code):
        """
        вывод ошибки по error.id
        """
        if code == 1:
            message = "Invalid JSON-RPC. Unknown RPC version"
            print self.time() + " - " + message
            return {"error": {"code": code, "message": message}}

    def settings_node(self):
        """
        конфигурация ноды
        """
        if os.path.isfile('/etc/gocloud/node/node.json'):
            with open('/etc/gocloud/node/node.json') as nodesettings_file:
                conf = json.load(nodesettings_file)
        else:
            print "[Errno 2] No such file or directory: '/etc/gocloud/node/node.json'"
            sys.exit(2)

        return conf

    def settings_vm(self):
        """
        конфигурационные параметры для виртуальных машин
        """
        if os.path.isfile('/etc/gocloud/node/vmsettings.json'):
            with open('/etc/gocloud/node/vmsettings.json') as vmsettings_file:
                conf = json.load(vmsettings_file)
        else:
            print "[Errno 2] No such file or directory: '/etc/gocloud/node/vmsettings.json'"
            sys.exit(2)

        return conf

    def linux_distribution(self):
        try:
            return platform.linux_distribution()
        except:
            return 0

    # network
    def all_interfaces(self):
        # arbitrary. raise if needed.
        max_possible = 128
        bytes = max_possible * 32
        s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        names = array.array('B', '\0' * bytes)
        outbytes = struct.unpack('iL', fcntl.ioctl(
            s.fileno(),
            0x8912,  # SIOCGIFCONF
            struct.pack('iL', bytes, names.buffer_info()[0])
        ))[0]
        namestr = names.tostring()
        lst = []
        for i in range(0, outbytes, 40):
            name = namestr[i:i+16].split('\0', 1)[0]
            ip   = namestr[i+20:i+24]
            lst.append((name, ip))
        return lst

    def format_ip(self, addr):
        return str(ord(addr[0])) + '.' + str(ord(addr[1])) + '.' + str(ord(addr[2])) + '.' + str(ord(addr[3]))

    def check_file_exists(self, filename):
        if os.path.isfile(filename):
            return True
        else:
            return False

    def server_request(self, server_url, request):
        params = {
            "request": json.dumps(request)
        }
        return urllib.urlopen(server_url, urllib.urlencode(params)).read()