import pandas as pd
from datetime import datetime
import numpy as np
import ujson
import asyncio
import sqlite3
import os
from tqdm import tqdm

async def save_json(symbol, data):
    os.makedirs("json/var", exist_ok=True)  # Ensure directory exists
    with open(f"json/var/{symbol}.json", 'w') as file:
        ujson.dump(data, file)

# Define risk rating scale
def assign_risk_rating(var):
    if var >= 25: 
        return 1
    elif var >= 20:
        return 2
    elif var >= 15:
        return 3
    elif var >= 10:
        return 4
    elif var >= 8:
        return 5
    elif var >= 6:
        return 6
    elif var >= 4:
        return 7
    elif var >= 2:
        return 8
    elif var >= 1:
        return 9
    else:
        return 10

def compute_var(df):
    # Calculate daily returns
    df['Returns'] = df['close'].pct_change()
    df = df.dropna()
    # Calculate VaR at 95% confidence level
    confidence_level = 0.95
    var = np.percentile(df['Returns'], 100 * (1 - confidence_level))
    var_N_days = round(var * np.sqrt(len(df)) * 100, 2)  # N days: the length of df represents the N days

    if var_N_days <= -100:
        var_N_days = -99

    return var_N_days  # Positive value represents a loss

async def run():
    start_date = "2015-01-01"
    end_date = datetime.today().strftime("%Y-%m-%d")

    con = sqlite3.connect('stocks.db')
    etf_con = sqlite3.connect('etf.db')
    crypto_con = sqlite3.connect('crypto.db')

    cursor = con.cursor()
    cursor.execute("PRAGMA journal_mode = wal")
    cursor.execute("SELECT DISTINCT symbol FROM stocks")
    stocks_symbols = [row[0] for row in cursor.fetchall()]

    etf_cursor = etf_con.cursor()
    etf_cursor.execute("PRAGMA journal_mode = wal")
    etf_cursor.execute("SELECT DISTINCT symbol FROM etfs")
    etf_symbols = [row[0] for row in etf_cursor.fetchall()]

    crypto_cursor = crypto_con.cursor()
    crypto_cursor.execute("PRAGMA journal_mode = wal")
    crypto_cursor.execute("SELECT DISTINCT symbol FROM cryptos")
    crypto_symbols = [row[0] for row in crypto_cursor.fetchall()]

    total_symbols = stocks_symbols + etf_symbols + crypto_symbols

    for symbol in tqdm(total_symbols):
        try:
            if symbol in etf_symbols:  
                query_con = etf_con
            elif symbol in crypto_symbols:  
                query_con = crypto_con
            elif symbol in stocks_symbols:  
                query_con = con
            else:
                continue

            query_template = """
                    SELECT
                        date, open, high, low, close, volume
                    FROM
                        "{symbol}"
                    WHERE
                        date BETWEEN ? AND ?
                """
            query = query_template.format(symbol=symbol)
            df = pd.read_sql_query(query, query_con, params=(start_date, end_date))

            # Convert date to datetime
            df['date'] = pd.to_datetime(df['date'])

            # Group by year and month
            monthly_groups = df.groupby(df['date'].dt.to_period('M'))
            history = []

            for period, group in monthly_groups:
                if len(group) >=19:  # Check if the month has at least 19 data points
                    var_data = compute_var(group)
                    history.append({'date': str(period), 'var': var_data})

            risk_rating = assign_risk_rating(abs(history[-1]['var']))
            outlook = 'Neutral'
            if risk_rating < 5:
                outlook = 'Risky'
            elif risk_rating > 5:
                outlook = 'Minimum Risk'
            res = {'rating': risk_rating, 'history': history, 'outlook': outlook}

            await save_json(symbol, res)

        except Exception as e:
            print(f"Error processing {symbol}: {e}")

    con.close()
    etf_con.close()
    crypto_con.close()

try:
    asyncio.run(run())
except Exception as e:
    print(e)