import datetime
import math
import numpy as np
import pandas as pd
import matplotlib.pyplot as plt
from pandas_datareader import data as pdr
import backtrader as bt

stockList = ["VOO"]
total_days_in_market = 365 * 10
month_sum = 500  # usd
period_months = 1
reserve = 5  # usd for comms etc
period_sum = month_sum * period_months


# import data
def get_data(stocks, start, end):
    stockData = pdr.get_data_yahoo(stocks, start, end)
    return stockData


endDate = datetime.datetime.now()
startDate = endDate - datetime.timedelta(days=total_days_in_market)
stockData = get_data(stockList[0], startDate, endDate)

actualStart: datetime.datetime = stockData.index[0]
print(actualStart)

data = bt.feeds.PandasData(dataname=stockData)


class LSI(bt.Strategy):
    def start(self):
        self.val_start = self.broker.get_cash()

    def nextstart(self):
        size = math.floor((self.broker.get_cash() - 10) / self.data[0])
        self.buy(size=size)

    def stop(self):
        # calculate actual returns
        self.roi = (self.broker.get_value() / self.val_start) - 1
        print("Starting Value:  ${:,.2f}".format(self.val_start))
        print("ROI:              {:.2f}%".format(self.roi * 100.0))
        print(
            "Annualised:       {:.2f}%".format(
                100 * ((1 + self.roi) ** (365 / (endDate - actualStart).days) - 1)
            )
        )
        print(
            "Gross Return:    ${:,.2f}".format(self.broker.get_value() - self.val_start)
        )


class PercentageCommisionScheme(bt.CommInfoBase):
    paras = (
        ("commission", 0.004),
        ("stocklike", True),
        ("commtype", bt.CommInfoBase.COMM_PERC),
    )

    def _getcommission(self, size, price, pseudoexec):
        return self.p.commission


class FormulaInvesting(bt.Strategy):
    params = dict(monthly_cash=month_sum, monthly_range=[5, 20])

    def __init__(self):
        self.order = None
        self.totalcost = 0
        self.comms = 0
        self.units = 0
        self.times = 0
        self.periods = 0

    def log(self, txt, dt=None):
        dt = dt or self.datas[0].datetime.date(0)
        # print("%s, %s" % (dt.isoformat(), txt))

    def start(self):
        self.broker.set_fundmode(fundmode=True, fundstartval=100.0)

        self.cash_start = self.broker.get_cash()
        self.val_start = 100.0

        # ADD A TIMER
        self.add_timer(
            when=bt.timer.SESSION_START,
            monthdays=[i for i in self.p.monthly_range],
            monthcarry=True
            # timername='buytimer',
        )

    def notify_order(self, order):
        if order.status in [order.Submitted, order.Accepted]:
            return

        if order.status in [order.Completed]:
            if order.isbuy():
                self.log(
                    "BUY EXECUTED, Price %.2f, Cost %.2f, Comm %.2f, Size %.0f"
                    % (
                        order.executed.price,
                        order.executed.value,
                        order.executed.comm,
                        order.executed.size,
                    )
                )

                self.units += order.executed.size
                self.totalcost += order.executed.value + order.executed.comm
                self.comms += order.executed.comm

            elif order.issell():
                self.log(
                    "SELL EXECUTED, Price %.2f, Cost %.2f, Comm %.2f, Size %.0f"
                    % (
                        order.executed.price,
                        order.executed.value,
                        order.executed.comm,
                        order.executed.size,
                    )
                )
                self.units -= order.executed.size
                # self.totalcost += order.executed.value
                self.totalcost += order.executed.comm
                self.comms -= order.executed.value

            self.times += 1

        elif order.status in [order.Canceled, order.Margin, order.Rejected]:
            self.log("Order Canceled/Margin/Rejected")
            print(order.status, [order.Canceled, order.Margin, order.Rejected])

        self.order = None

    def stop(self):
        # calculate actual returns
        self.roi = (self.broker.get_value() / self.cash_start) - 1
        self.froi = self.broker.get_fundvalue() - self.val_start
        value = self.datas[0].close * self.units + self.broker.get_cash()
        print("Time in Market: {:.1f} years".format((endDate - actualStart).days / 365))
        print("#Times:         {:.0f}".format(self.times))
        print("#Units:         {:.0f}".format(self.units))
        print("Value:         ${:,.2f}".format(value))
        print("Commissions:   ${:.2f}".format(self.froi))
        print("Cost:          ${:,.2f}".format(self.totalcost))
        print("Gross Return:  ${:,.2f}".format(value - self.totalcost))
        print("Gross %:        {:.2f}%".format((value / self.totalcost - 1) * 100))
        print("ROI:            {:.2f}%".format(100.0 * self.roi))
        print("Fund Value:     {:.2f}%".format(self.froi))
        print(
            "Annualised:     {:.2f}%".format(
                100
                * ((1 + self.froi / 100) ** (365 / (endDate - actualStart).days) - 1)
            )
        )

    def notify_timer(self, timer, when, *args):
        self.periods += 1
        self.broker.add_cash(self.p.monthly_cash)
        self.formula()


class VA(FormulaInvesting):
    def formula(self):
        target_value = (self.periods) * self.p.monthly_cash - reserve
        self.order_target_value(target=target_value)


class DCA(FormulaInvesting):
    def formula(self):
        target_value = self.broker.get_value() - reserve
        self.order_target_value(target=target_value)


def run(strategy, data):
    cerebro = bt.Cerebro(stdstats=False)

    cerebro.addobserver(bt.observers.Broker)
    cerebro.addobserver(bt.observers.BuySell)

    cerebro.adddata(data)
    cerebro.addstrategy(strategy)
    print("-" * 50)
    print(strategy.__name__)

    # Broker Information
    broker_args = dict(coc=True)
    cerebro.broker = bt.brokers.BackBroker(**broker_args)
    comminfo = PercentageCommisionScheme()
    cerebro.broker.addcommissioninfo(comminfo)

    cerebro.broker.set_cash(period_sum)
    cerebro.run()
    cerebro.plot(iplot=False, style="candlestick")


if __name__ == "__main__":
    # run(LSI, 100000, data)
    run(DCA, data)
    run(VA, data)