#!/usr/bin/env python
# -*- coding: utf-8; py-indent-offset:4 -*-
###############################################################################
#
# Copyright (C) 2015, 2016, 2017 Daniel Rodriguez
#
# 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/>.
#
###############################################################################
from __future__ import (absolute_import, division, print_function,
                        unicode_literals)

import datetime
import struct
import os.path

from .. import feed
from .. import TimeFrame
from ..utils import date2num


class VChartData(feed.DataBase):
    '''
    Support for `Visual Chart <www.visualchart.com>`_ binary on-disk files for
    both daily and intradaily formats.

    Note:

      - ``dataname``: to file or open file-like object

        If a file-like object is passed, the ``timeframe`` parameter will be
        used to determine which is the actual timeframe.

        Else the file extension (``.fd`` for daily and ``.min`` for intraday)
        will be used.
    '''

    def start(self):
        super(VChartData, self).start()

        # Not yet known if a extension is needed
        self.ext = ''

        if not hasattr(self.p.dataname, 'read'):
            # assume is a string because it has no write method

            if self.p.dataname.endswith('.fd'):
                self.p.timeframe = TimeFrame.Days
            elif self.p.dataname.endswith('.min'):
                self.p.timeframe = TimeFrame.Minutes
            else:
                # Neither fd nor min ... just the code, assign extension
                if self.p.timeframe == TimeFrame.Days:
                    self.ext = '.fd'
                else:
                    self.ext = '.min'

        if self.p.timeframe >= TimeFrame.Days:
            self.barsize = 28
            self.dtsize = 1
            self.barfmt = 'IffffII'
        else:
            self.dtsize = 2
            self.barsize = 32
            self.barfmt = 'IIffffII'

        self.f = None
        if hasattr(self.p.dataname, 'read'):
            # A file has been passed in (ex: from a GUI)
            self.f = self.p.dataname
        else:
            dataname = self.p.dataname + self.ext
            # Let an exception propagate
            self.f = open(dataname, 'rb')

    def stop(self):
        if self.f is not None:
            self.f.close()
            self.f = None

    def _load(self):
        if self.f is None:
            return False

        # Let an exception propagate to let the caller know
        bardata = self.f.read(self.barsize)
        if not bardata:
            return False

        bdata = struct.unpack(self.barfmt, bardata)

        # Years are stored as if they had 500 days
        y, md = divmod(bdata[0], 500)
        # Months are stored as if they had 32 days
        m, d = divmod(md, 32)
        dt = datetime.datetime(y, m, d)

        if self.dtsize > 1:  # Minute Bars
            # Daily Time is stored in seconds
            hhmm, ss = divmod(bdata[1], 60)
            hh, mm = divmod(hhmm, 60)
            dt = dt.replace(hour=hh, minute=mm, second=ss)

        self.lines.datetime[0] = date2num(dt)

        o, h, l, c, v, oi = bdata[self.dtsize:]
        self.lines.open[0] = o
        self.lines.high[0] = h
        self.lines.low[0] = l
        self.lines.close[0] = c
        self.lines.volume[0] = v
        self.lines.openinterest[0] = oi

        return True


class VChartFeed(feed.FeedBase):
    DataCls = VChartData

    params = (('basepath', ''),) + DataCls.params._gettuple()

    def _getdata(self, dataname, **kwargs):
        maincode = dataname[0:2]
        subcode = dataname[2:6]

        datapath = os.path.join(self.p.basepath,
                                'RealServer', 'Data',
                                maincode, subcode,  # 01 00XX
                                dataname)

        newkwargs = self.p._getkwargs()
        newkwargs.update(kwargs)
        kwargs['dataname'] = datapath
        return self.DataCls(**kwargs)
