import datetime
import csv
from binance.enums import HistoricalKlinesType


class Candles:
    def __init__(self, config, exchange):
        # Keep a reference to the exchange object.
        self.exchange = exchange

        # The maximum amount of data to load into memory at one time.
        self.max_data_loaded = config.max_data_loaded

        # A reference to the interface configuration
        self.config = config

        # The entire loaded candle history
        self.candlesticks = []

        # List of dictionaries of timestamped high, low, and closing values
        self.latest_high_values = []
        self.latest_low_values = []
        self.latest_close_values = []

        # Values of the last candle received
        self.last_candle = None

        # List of dictionaries of timestamped volume values
        self.latest_vol = []

        # Set the instance variable of candlesticks, latest_close_values, high, low, closing, volume, and last_candle
        self.set_candle_history(symbol=config.trading_pair, interval=config.chart_interval)

    def set_new_candle(self, cdata):
        #  TODO: this is not updating self.candlesticks[]. I think it is because it is
        #  todo: not in the raw format received earlier. check that the format is the same.
        #  todo: candlesticks is accessed by get_candle_history() while init the charts
        self.last_candle = cdata
        self.latest_close_values.append({'time': cdata['time'], 'close': cdata['close']})
        self.latest_high_values.append({'time': cdata['time'], 'high': cdata['high']})
        self.latest_low_values.append({'time': cdata['time'], 'low': cdata['low']})
        self.latest_vol.append({'time': cdata['time'], 'value': cdata['vol']})
        return True

    def load_candle_history(self, symbol, interval):
        """ Retrieve candlestick history from a file and append it with
            more recent exchange data while updating the file record.
            This method only get called if the <symbol> data is requested.
            This is to avoid maintaining irrelevant data files."""

        start_datetime = datetime.datetime(2017, 1, 1)
        # Create a filename from the function parameters.
        # Format is symbol_interval_start_date: example - 'BTCUSDT_15m_2017-01-01'
        file_name = 'data' + '/' + f'{symbol}_{interval}_{start_datetime.date()}'

        # List of price data. <Open_time>,<Open>,<High>,<Low>,<Close>,
        #                     <Ignore><Close_time><Ignore>
        #                     <Number_of_bisic_data>,<Ignore,Ignore,Ignore>
        candlesticks = []

        try:
            # Populate <candlesticks> from <file_name> if it exists.
            print(f'Attempting to open: {file_name}')
            with open(file_name, 'r') as file:
                reader = csv.reader(file, delimiter=',')
                # Load the data here
                for row in reader:
                    candlesticks.append(row)
            print('File loaded')
            # Open <file_name> for appending
            file = open(file_name, 'a', newline='')
            candlestick_writer = csv.writer(file, delimiter=',')

        except IOError:
            # If the file doesn't exist it must be created.
            print(f'{file_name} not found: Creating the file')
            # Open <file_name> for writing
            file = open(file_name, 'w', newline='')
            candlestick_writer = csv.writer(file, delimiter=',')

        # If no candlesticks were loaded from file. Set a date to start loading from in the
        # variable <last_candle_stamp> with a default value stored in <start_datetime>.
        if not candlesticks:
            last_candle_stamp = start_datetime.timestamp() * 1000
        else:
            # Set <last_candle_stamp> with the timestamp of the last candles on file
            last_candle_stamp = candlesticks[-1][0]
        # Request any missing candlestick data from the exchange
        recent_candlesticks = self.exchange.client.get_historical_klines(symbol,
                                                                         interval,
                                                                         start_str=int(last_candle_stamp),
                                                                         klines_type=HistoricalKlinesType.FUTURES)
        # Discard the first row of candlestick data as it will be a duplicate***DOUBLE CHECK THIS
        recent_candlesticks.pop(0)
        # Append the candlestick list and the file
        for candlestick in recent_candlesticks:
            candlesticks.append(candlestick)
            candlestick_writer.writerow(candlestick)
        # Close the file and return the entire candlestick history
        file.close()
        return candlesticks

    def set_candle_history(self, symbol=None, interval=None, max_data_loaded=None):
        if not max_data_loaded:
            max_data_loaded = self.max_data_loaded
        if not symbol:
            symbol = self.config.trading_pair
            print(f'set_candle_history(): No symbol provided. Using{symbol}')
        if not interval:
            interval = self.config.chart_interval
            print(f'set_candle_history(): No interval provided. Using{interval}')
        if self.candlesticks:
            print(f'set_candle_history(): Reloading {interval} candles.')
        else:
            print(f'set_candle_history(): Loading {interval} candles.')
        # Load candles from file
        cdata = self.load_candle_history(symbol, interval)
        # Trim the beginning of the returned list to size of max_data_loaded of less
        if len(cdata) < max_data_loaded:
            max_data_loaded = len(cdata)
        self.candlesticks = cdata[-max_data_loaded:]
        # Set an instance dictionary of timestamped high, low, closing values
        self.set_latest_values('high')
        self.set_latest_values('low')
        self.set_latest_values('close')
        # Extract the volume data from self.candlesticks and store it in self.latest_vol
        self.set_latest_vol()

        # Set an instance reference of the last candle
        self.last_candle = self.convert_candle(self.candlesticks[-1])
        print('set_candle_history(): Candle data Loaded')
        return

    def set_latest_vol(self):
        # Extracts a list of volume values from all the loaded candlestick
        # data and store it in a dictionary keyed to timestamp of measurement.
        latest_vol = []
        last_clp = 0
        for data in self.candlesticks:
            clp = int(float(data[4]))
            if clp < last_clp:
                color = 'rgba(255,82,82, 0.8)'  # red
            else:
                color = 'rgba(0, 150, 136, 0.8)'  # green

            vol_data = {
                "time": int(data[0]) / 1000,
                "value": int(float(data[5])),
                "color": color
            }
            last_clp = clp
            latest_vol.append(vol_data)
        self.latest_vol = latest_vol
        return

    def get_latest_vol(self, num_record=500):
        # Returns the latest volume values
        if self.latest_vol:
            if len(self.latest_vol) < num_record:
                print('Warning: get_latest_vol() - Requested too more records then available')
                num_record = len(self.latest_vol)
            return self.latest_vol[-num_record:]
        else:
            raise ValueError('Warning: get_latest_vol(): Values are not set')

    def set_latest_values(self, value_name):
        # Extracts a list of values from all the loaded candlestick data
        # and store it in a dictionary keyed to timestamp of measurement.
        index = {'high': 2, 'low': 3, 'close': 4}
        latest_values = []
        for data in self.candlesticks:
            data = {
                "time": int(data[0]) / 1000,
                value_name: data[index[value_name]]
            }
            latest_values.append(data)
        if value_name == 'high':
            self.latest_high_values = latest_values
        if value_name == 'low':
            self.latest_low_values = latest_values
        if value_name == 'close':
            self.latest_close_values = latest_values
        return

    def get_latest_values(self, value_name, num_record=1):
        # Returns the latest values
        values = None
        if value_name == 'high':
            values = self.latest_high_values
        if value_name == 'low':
            values = self.latest_low_values
        if value_name == 'close':
            values = self.latest_close_values
        if values is None:
            raise ValueError(f'Warning: latest_values(): "{value_name}" values are not set.')
        if len(values) < num_record:
            print('Warning: get_latest_values() - Requested more records then available')
            num_record = len(values)
        return values[-num_record:]

    @staticmethod
    def convert_candle(candle):
        # Converts the binance candle format to what lightweight charts expects.
        candlestick = {
            "time": int(candle[0]) / 1000,
            "open": candle[1],
            "high": candle[2],
            "low": candle[3],
            "close": candle[4]
        }
        return candlestick

    def get_candle_history(self, symbol, interval, num_records):
        # Returns a specified number of candle records from memory in the lightweight
        # charts format.
        if len(self.candlesticks) < num_records:
            print('Warning: get_candle_history() Requested more records then available')
            num_records = len(self.candlesticks)

        # Drop everything but the requested number of records
        candlesticks = self.candlesticks[-num_records:]

        # Reformat relevant candlestick data into a list of python dictionary objects.
        # Binance stores timestamps in milliseconds but lightweight charts doesn't,
        # so it gets divided by 1000
        processed_candlesticks = []
        for candle in candlesticks:
            candlestick = self.convert_candle(candle)
            processed_candlesticks.append(candlestick)
        # Return a list of candlestick objects
        return processed_candlesticks