import logging
import shutil
from copy import deepcopy
from datetime import datetime, timedelta, timezone
from pathlib import Path
from typing import Any, Dict, List, Optional

from pandas import DataFrame

from freqtrade.configuration import TimeRange
from freqtrade.exchange import timeframe_to_minutes
from freqtrade.loggers.set_log_levels import (reduce_verbosity_for_bias_tester,
                                              restore_verbosity_for_bias_tester)
from freqtrade.optimize.backtesting import Backtesting
from freqtrade.optimize.base_analysis import BaseAnalysis, VarHolder


logger = logging.getLogger(__name__)


class RecursiveAnalysis(BaseAnalysis):

    def __init__(self, config: Dict[str, Any], strategy_obj: Dict):

        self._startup_candle = config.get('startup_candle', [199, 399, 499, 999, 1999])

        super().__init__(config, strategy_obj)
        
        self.partial_varHolder_array: List[VarHolder] = []
        self.partial_varHolder_lookahead_array: List[VarHolder] = []

        
        self.dict_recursive: Dict[str, Any] = dict()

    # For recursive bias check
    # analyzes two data frames with processed indicators and shows differences between them.
    def analyze_indicators(self):

        pair_to_check = self.local_config['pairs'][0]
        logger.info("Start checking for recursive bias")

        # check and report signals
        base_last_row = self.full_varHolder.indicators[pair_to_check].iloc[-1]

        for part in self.partial_varHolder_array:
            part_last_row = part.indicators[pair_to_check].iloc[-1]

            compare_df = base_last_row.compare(part_last_row)
            if compare_df.shape[0] > 0:
                # print(compare_df)
                for col_name, values in compare_df.items():
                    # print(col_name)
                    if 'other' == col_name:
                        continue
                    indicators = values.index

                    for indicator in indicators:
                        if (indicator not in self.dict_recursive):
                            self.dict_recursive[indicator] = {}

                        values_diff = compare_df.loc[indicator]
                        values_diff_self = values_diff.loc['self']
                        values_diff_other = values_diff.loc['other']
                        diff = (values_diff_other - values_diff_self) / values_diff_self * 100

                        self.dict_recursive[indicator][part.startup_candle] = f"{diff:.3f}%"

            else:
                logger.info("No difference found. Stop the process.")
                break

    # For lookahead bias check
    # analyzes two data frames with processed indicators and shows differences between them.
    def analyze_indicators_lookahead(self):

        pair_to_check = self.local_config['pairs'][0]
        logger.info("Start checking for lookahead bias on indicators only")

        part = self.partial_varHolder_lookahead_array[0]
        part_last_row = part.indicators[pair_to_check].iloc[-1]
        date_to_check = part_last_row['date']
        index_to_get = (self.full_varHolder.indicators[pair_to_check]['date'] == date_to_check)
        base_row_check = self.full_varHolder.indicators[pair_to_check].loc[index_to_get].iloc[-1]

        check_time = part.to_dt.strftime('%Y-%m-%dT%H:%M:%S')

        logger.info(f"Check indicators at {check_time}")
        # logger.info(f"vs {part_timerange} with {part.startup_candle} startup candle")

        compare_df = base_row_check.compare(part_last_row)
        if compare_df.shape[0] > 0:
            # print(compare_df)
            for col_name, values in compare_df.items():
                # print(col_name)
                if 'other' == col_name:
                    continue
                indicators = values.index

                for indicator in indicators:
                    logger.info(f"=> found lookahead in indicator {indicator}")
                    # logger.info("base value {:.5f}".format(values_diff_self))
                    # logger.info("part value {:.5f}".format(values_diff_other))

        else:
            logger.info("No lookahead bias on indicators found. Stop the process.")

    def fill_partial_varholder(self, start_date, startup_candle):
        partial_varHolder = VarHolder()

        partial_varHolder.from_dt = start_date
        partial_varHolder.to_dt = self.full_varHolder.to_dt
        partial_varHolder.startup_candle = startup_candle

        self.local_config['startup_candle_count'] = startup_candle

        self.prepare_data(partial_varHolder, self.local_config['pairs'])

        self.partial_varHolder_array.append(partial_varHolder)

    def fill_partial_varholder_lookahead(self, end_date):
        partial_varHolder = VarHolder()

        partial_varHolder.from_dt = self.full_varHolder.from_dt
        partial_varHolder.to_dt = end_date

        self.prepare_data(partial_varHolder, self.local_config['pairs'])

        self.partial_varHolder_lookahead_array.append(partial_varHolder)

    def start(self) -> None:

        super().start()

        reduce_verbosity_for_bias_tester()
        start_date_full = self.full_varHolder.from_dt
        end_date_full = self.full_varHolder.to_dt

        timeframe_minutes = timeframe_to_minutes(self.full_varHolder.timeframe)

        end_date_partial = start_date_full + timedelta(minutes=int(timeframe_minutes * 10))

        self.fill_partial_varholder_lookahead(end_date_partial)

        # restore_verbosity_for_bias_tester()

        start_date_partial = end_date_full - timedelta(minutes=int(timeframe_minutes))

        for startup_candle in self._startup_candle:
            self.fill_partial_varholder(start_date_partial, int(startup_candle))

        # Restore verbosity, so it's not too quiet for the next strategy
        restore_verbosity_for_bias_tester()

        self.analyze_indicators()
        self.analyze_indicators_lookahead()