from __future__ import division

import struct

from minecraft.networking.types.basic import (
    Type, Byte, Short, Integer, Long, Float, Double,
    ShortPrefixedByteArray, Boolean, VarInt, TrailingByteArray,
    Position, String, UnsignedByte
)
from minecraft.networking.types.utility import Vector


class IntegerPrefixedByteArray(Type):
    @staticmethod
    def read(file_object):
        length = Integer.read(file_object)
        return struct.unpack(str(length) + "s", file_object.read(length))[0]

    @staticmethod
    def send(value, socket):
        Integer.send(len(value), socket)
        socket.send(value)


TAG_End = 0
TAG_Byte = 1
TAG_Short = 2
TAG_Int = 3
TAG_Long = 4
TAG_Float = 5
TAG_Double = 6
TAG_Byte_Array = 7
TAG_String = 8
TAG_List = 9
TAG_Compound = 10
TAG_Int_Array = 11
TAG_Long_Array = 12

class Nbt(Type):
    @staticmethod
    def read(file_object):
        type_id = Byte.read(file_object)
        if type_id != TAG_Compound:
            #raise Exception("Invalid NBT header")
            return None
        name = ShortPrefixedByteArray.read(file_object).decode('utf-8')
        a = Nbt.decode_tag(file_object, TAG_Compound)
        a['_name'] = name
        return a

    @staticmethod
    def decode_tag(file_object, type_id):
        if type_id == TAG_Byte:
            return Byte.read(file_object)
        elif type_id == TAG_Short:
            return Short.read(file_object)
        elif type_id == TAG_Int:
            return Integer.read(file_object)
        elif type_id == TAG_Long:
            return Long.read(file_object)
        elif type_id == TAG_Float:
            return Float.read(file_object)
        elif type_id == TAG_Double:
            return Double.read(file_object)
        elif type_id == TAG_Byte_Array:
            return IntegerPrefixedByteArray.read(file_object).decode('utf-8')
        elif type_id == TAG_String:
            return ShortPrefixedByteArray.read(file_object)
        elif type_id == TAG_List:
            list_type_id = Byte.read(file_object)
            size = Integer.read(file_object)
            a = []
            for i in range(size):
                a.append(Nbt.decode_tag(file_object, list_type_id))
            return a
        elif type_id == TAG_Compound:
            c = { }
            child_type_id = Byte.read(file_object)
            while child_type_id != TAG_End:
                child_name = ShortPrefixedByteArray.read(file_object).decode('utf-8')
                c[child_name] = Nbt.decode_tag(file_object, child_type_id)
                child_type_id = Byte.read(file_object)
            return c
        elif type_id == TAG_Int_Array:
            size = Integer.read(file_object)
            a = []
            for i in range(size):
                a.append(Integer.read(file_object))
            return a
        elif type_id == TAG_Long_Array:
            size = Integer.read(file_object)
            a = []
            for i in range(size):
                a.append(Long.read(file_object))
            return a
        else:
            raise Exception("Invalid NBT tag type")

    @staticmethod
    def send(value, socket):
        # TODO
        pass


class Slot(Type):
    def __init__(self, present, item_id, item_count, nbt):
        self.present = present
        self.item_id = item_id
        self.item_count = item_count
        self.nbt = nbt

    def __str__(self):
        return str(self.__dict__)
    def __repr__(self):
        return 'Slot(present={}, item_id={}, item_count={}, nbt={}'.format(
            self.present, self.item_id, self.item_count, self.nbt)

    @staticmethod
    def read(file_object):
        present = Boolean.read(file_object)
        if present:
            item_id = VarInt.read(file_object)
            item_count = Byte.read(file_object)
            nbt = Nbt.read(file_object)
        else:
            item_id = None
            item_count = None
            nbt = None
        return Slot(present, item_id, item_count, nbt)

    @staticmethod
    def send(value, socket):
        Boolean.send(value.present, socket)
        VarInt.send(value.item_id, socket)
        Byte.send(value.item_count, socket)
        Byte.send(0x00, socket)


class Entry(Type):
    types = {
        0: Byte,
        1: VarInt,
        2: Float,
        3: String,
        5: Boolean,
        6: Slot,
        7: Boolean,
        9: Position,
        18: VarInt,
    }

    def __init__(self, index, type, value):
        self.index = index
        self.type = type
        self.value = value

    def __str__(self):
        return str(self.__dict__)
    def __repr__(self):
        return 'Entry(index={}, type={}, value={})'.format(
            self.index, self.type, self.value)

    @staticmethod
    def read(file_object, context):
        index = UnsignedByte.read(file_object)
        if index == 0xff: return None
        type = VarInt.read(file_object)
        try:
            value = Entry.types[type].read(file_object)
        except TypeError:
            value = Entry.types[type].read_with_context(file_object, context)
        except KeyError:
            return None
        return Entry(index, type, value)


class Trade(Type):
    fields = (
        'input_item_1',
        'output_item',
        'has_second_item',
        'input_item_2',
        'trade_disabled',
        'num_uses',
        'max_num_uses',
        'xp',
        'special_price',
        'price_multiplier',
        'demand',
    )

    def __str__(self):
        return str(self.__dict__)
    def __repr__(self):
        inner_str = ', '.join('%s=%s' % (a, getattr(self, a, None)) for a in self.fields if hasattr(self, a))
        return 'Trade(%s)' % inner_str

    @staticmethod
    def read(file_object):
        trade = Trade()
        trade.input_item_1 = Slot.read(file_object)
        trade.output_item = Slot.read(file_object)
        trade.has_second_item = Boolean.read(file_object)
        if trade.has_second_item:
            trade.input_item_2 = Slot.read(file_object)
        trade.trade_disabled = Boolean.read(file_object)
        trade.num_uses = Integer.read(file_object)
        trade.max_num_uses = Integer.read(file_object)
        trade.xp = Integer.read(file_object)
        trade.special_price = Integer.read(file_object)
        trade.price_multiplier = Float.read(file_object)
        trade.demand = Integer.read(file_object)
        return trade