import matplotlib matplotlib.use('Agg') import matplotlib.pyplot as plt import matplotlib.dates as mdates from datetime import datetime from typing import Dict, List, Optional import logging import io logger = logging.getLogger(__name__) class ChartGenerator: """Generates stock price charts using matplotlib.""" @staticmethod def create_price_chart( ticker: str, candle_data: Dict[str, List], company_name: Optional[str] = None ) -> Optional[io.BytesIO]: """ Create a price chart from candle data. Args: ticker: Stock ticker symbol candle_data: Dictionary with timestamps, open, high, low, close, volume company_name: Optional company name for title Returns: BytesIO buffer containing the chart image, or None if error """ try: # Convert timestamps to datetime objects dates = [datetime.fromtimestamp(ts) for ts in candle_data['timestamps']] closes = candle_data['close'] # Create figure and axis fig, ax = plt.subplots(figsize=(12, 6), facecolor='#1e1e1e') ax.set_facecolor('#2d2d2d') # Plot closing prices ax.plot(dates, closes, color='#00d4ff', linewidth=2) # Fill area under the line ax.fill_between(dates, closes, alpha=0.3, color='#00d4ff') # Format x-axis ax.xaxis.set_major_formatter(mdates.DateFormatter('%m/%d')) ax.xaxis.set_major_locator(mdates.AutoDateLocator()) plt.xticks(rotation=45, ha='right') # Grid styling ax.grid(True, alpha=0.2, color='#ffffff', linestyle='-', linewidth=0.5) # Labels and title title = f"{company_name} ({ticker})" if company_name else ticker ax.set_title(title, color='#ffffff', fontsize=14, fontweight='bold', pad=20) ax.set_xlabel('Date', color='#ffffff', fontsize=10) ax.set_ylabel('Price ($)', color='#ffffff', fontsize=10) # Tick colors ax.tick_params(colors='#ffffff', which='both') # Spine colors for spine in ax.spines.values(): spine.set_color('#444444') # Tight layout plt.tight_layout() # Save to buffer buffer = io.BytesIO() plt.savefig(buffer, format='png', facecolor='#1e1e1e', dpi=100) buffer.seek(0) plt.close(fig) return buffer except Exception as e: logger.error(f"Error generating chart for {ticker}: {e}") return None @staticmethod def create_candlestick_chart( ticker: str, candle_data: Dict[str, List], company_name: Optional[str] = None ) -> Optional[io.BytesIO]: """ Create a candlestick chart from candle data. Args: ticker: Stock ticker symbol candle_data: Dictionary with timestamps, open, high, low, close, volume company_name: Optional company name for title Returns: BytesIO buffer containing the chart image, or None if error """ try: # Convert timestamps to datetime objects dates = [datetime.fromtimestamp(ts) for ts in candle_data['timestamps']] opens = candle_data['open'] highs = candle_data['high'] lows = candle_data['low'] closes = candle_data['close'] # Create figure and axis fig, ax = plt.subplots(figsize=(12, 6), facecolor='#1e1e1e') ax.set_facecolor('#2d2d2d') # Calculate bar width width = 0.6 # Plot candlesticks for i in range(len(dates)): color = '#00ff88' if closes[i] >= opens[i] else '#ff4444' # High-low line ax.plot([dates[i], dates[i]], [lows[i], highs[i]], color=color, linewidth=1) # Open-close rectangle height = abs(closes[i] - opens[i]) bottom = min(opens[i], closes[i]) ax.bar(dates[i], height, width, bottom=bottom, color=color, alpha=0.8) # Format x-axis ax.xaxis.set_major_formatter(mdates.DateFormatter('%m/%d')) ax.xaxis.set_major_locator(mdates.AutoDateLocator()) plt.xticks(rotation=45, ha='right') # Grid styling ax.grid(True, alpha=0.2, color='#ffffff', linestyle='-', linewidth=0.5) # Labels and title title = f"{company_name} ({ticker})" if company_name else ticker ax.set_title(title, color='#ffffff', fontsize=14, fontweight='bold', pad=20) ax.set_xlabel('Date', color='#ffffff', fontsize=10) ax.set_ylabel('Price ($)', color='#ffffff', fontsize=10) # Tick colors ax.tick_params(colors='#ffffff', which='both') # Spine colors for spine in ax.spines.values(): spine.set_color('#444444') # Tight layout plt.tight_layout() # Save to buffer buffer = io.BytesIO() plt.savefig(buffer, format='png', facecolor='#1e1e1e', dpi=100) buffer.seek(0) plt.close(fig) return buffer except Exception as e: logger.error(f"Error generating candlestick chart for {ticker}: {e}") return None