"""
Data fetching interfaces for DeltaFQ.
"""

import pandas as pd
from typing import List, Optional
from ..core.base import BaseComponent
from ..core.exceptions import DataError


class DataFetcher(BaseComponent):
    """Data fetcher for various sources."""
    
    def __init__(self, source: str = "yahoo", **kwargs):
        """Initialize data fetcher."""
        super().__init__(**kwargs)
        self.source = source
    
    def initialize(self) -> bool:
        """Initialize the data fetcher."""
        self.logger.info(f"Initializing data fetcher with source: {self.source}")
        return True
    
    def fetch_stock_data(self, symbol: str, start_date: str, end_date: str = None) -> pd.DataFrame:
        """Fetch stock data for given symbol."""
        try:
            # Placeholder implementation
            self.logger.info(f"Fetching data for {symbol} from {start_date} to {end_date}")
            
            # This would be replaced with actual data fetching logic
            dates = pd.date_range(start=start_date, end=end_date or "2024-01-01", freq='D')
            data = pd.DataFrame({
                'date': dates,
                'open': 100.0,
                'high': 105.0,
                'low': 95.0,
                'close': 102.0,
                'volume': 1000000
            })
            
            return data
        except Exception as e:
            raise DataError(f"Failed to fetch data for {symbol}: {str(e)}")
    
    def fetch_multiple_symbols(self, symbols: List[str], start_date: str, end_date: str = None) -> dict:
        """Fetch data for multiple symbols."""
        data_dict = {}
        for symbol in symbols:
            data_dict[symbol] = self.fetch_stock_data(symbol, start_date, end_date)
        return data_dict


