from datetime import datetime, time

import pandas as pd
import plotly.graph_objects as go
import streamlit as st

from frontend.st_utils import get_backend_api_client, initialize_st_page

# Initialize Streamlit page
initialize_st_page(title="Download Candles", icon="💾")
backend_api_client = get_backend_api_client()

c1, c2, c3, c4 = st.columns([2, 2, 2, 0.5])
with c1:
    connector = st.selectbox("Exchange",
                             ["binance_perpetual", "binance", "gate_io", "gate_io_perpetual", "kucoin", "ascend_ex"],
                             index=0)
    trading_pair = st.text_input("Trading Pair", value="BTC-USDT")
with c2:
    interval = st.selectbox("Interval", options=["1m", "3m", "5m", "15m", "1h", "4h", "1d", "1s"])
with c3:
    start_date = st.date_input("Start Date", value=datetime(2023, 1, 1))
    end_date = st.date_input("End Date", value=datetime(2023, 1, 2))
with c4:
    get_data_button = st.button("Get Candles!")

if get_data_button:
    start_datetime = datetime.combine(start_date, time.min)
    end_datetime = datetime.combine(end_date, time.max)
    if end_datetime < start_datetime:
        st.error("End Date should be greater than Start Date.")
        st.stop()

    candles = backend_api_client.market_data.get_historical_candles(
        connector_name=connector,
        trading_pair=trading_pair,
        interval=interval,
        start_time=int(start_datetime.timestamp()),
        end_time=int(end_datetime.timestamp())
    )

    candles_df = pd.DataFrame(candles)
    candles_df.index = pd.to_datetime(candles_df["timestamp"], unit='s')

    # Plotting the candlestick chart
    fig = go.Figure(data=[go.Candlestick(
        x=candles_df.index,
        open=candles_df['open'],
        high=candles_df['high'],
        low=candles_df['low'],
        close=candles_df['close']
    )])
    fig.update_layout(
        height=1000,
        title="Candlesticks",
        xaxis_title="Time",
        yaxis_title="Price",
        template="plotly_dark",
        showlegend=False
    )
    fig.update_xaxes(rangeslider_visible=False)
    fig.update_yaxes(title_text="Price")
    st.plotly_chart(fig, use_container_width=True)

    # Generating CSV and download button
    csv = candles_df.to_csv(index=False)
    filename = f"{connector}_{trading_pair}_{start_date.strftime('%Y%m%d')}_{end_date.strftime('%Y%m%d')}.csv"
    st.download_button(
        label="Download Candles as CSV",
        data=csv,
        file_name=filename,
        mime='text/csv',
    )