import pandas as pd
from datetime import datetime, timezone, timedelta
import plotly.graph_objects as go

from database.operations import get_database_operations
from utils.logger import get_logger
from utils.timeframe_utils import load_timeframe_options

from .builder import ChartBuilder
from .utils import format_price, format_volume

logger = get_logger("charts_data")

def get_supported_symbols():
    """Get list of symbols that have data in the database."""
    builder = ChartBuilder()
    # Test query - consider optimizing or removing if not critical for initial check
    candles = builder.fetch_market_data("BTC-USDT", "1m", days_back=1)  
    if candles:
        try:
            db = get_database_operations(logger)
            with db.market_data.get_session() as session:
                from sqlalchemy import text
                result = session.execute(text("SELECT DISTINCT symbol FROM market_data ORDER BY symbol"))
                return [row[0] for row in result]
        except Exception as e:
            logger.error(f"Error fetching supported symbols from DB: {e}")
            pass
    
    return ['BTC-USDT', 'ETH-USDT']  # Fallback

def get_supported_timeframes():
    """Get list of timeframes that have data in the database."""
    builder = ChartBuilder()
    # Test query - consider optimizing or removing if not critical for initial check
    candles = builder.fetch_market_data("BTC-USDT", "1m", days_back=1)  
    if candles:
        try:
            db = get_database_operations(logger)
            with db.market_data.get_session() as session:
                from sqlalchemy import text
                result = session.execute(text("SELECT DISTINCT timeframe FROM market_data ORDER BY timeframe"))
                return [row[0] for row in result]
        except Exception as e:
            logger.error(f"Error fetching supported timeframes from DB: {e}")
            pass
    
    # Fallback uses values from timeframe_options.json for consistency
    return [item['value'] for item in load_timeframe_options() if item['value'] in ['5s', '1m', '15m', '1h']] 

def get_market_statistics(symbol: str, timeframe: str = "1h", days_back: int = 1): # Changed from days_back: Union[int, float] to int
    """Calculate market statistics from recent data over a specified period."""
    builder = ChartBuilder()
    candles = builder.fetch_market_data(symbol, timeframe, days_back=days_back)
    
    if not candles:
        return {'Price': 'N/A', f'Change ({days_back}d)': 'N/A', f'Volume ({days_back}d)': 'N/A', f'High ({days_back}d)': 'N/A', f'Low ({days_back}d)': 'N/A'}
    
    df = pd.DataFrame(candles)
    latest = df.iloc[-1]
    current_price = float(latest['close'])
    
    # Calculate change over the period
    if len(df) > 1:
        price_period_ago = float(df.iloc[0]['open'])
        change_percent = ((current_price - price_period_ago) / price_period_ago) * 100
    else:
        change_percent = 0
    
    # Determine label for period (e.g., "24h", "7d", "1h")
    # This part should be updated if `days_back` can be fractional again.
    if days_back == 1/24:
        period_label = "1h"
    elif days_back == 4/24:
        period_label = "4h"
    elif days_back == 6/24:
        period_label = "6h"
    elif days_back == 12/24:
        period_label = "12h"
    elif days_back < 1: # For other fractional days, show as hours
        period_label = f"{int(days_back * 24)}h"
    elif days_back == 1:
        period_label = "24h" # Keep 24h for 1 day for clarity
    else:
        period_label = f"{days_back}d"

    return {
        'Price': format_price(current_price, decimals=2),
        f'Change ({period_label})': f"{'+' if change_percent >= 0 else ''}{change_percent:.2f}%",
        f'Volume ({period_label})': format_volume(df['volume'].sum()),
        f'High ({period_label})': format_price(df['high'].max(), decimals=2),
        f'Low ({period_label})': format_price(df['low'].min(), decimals=2)
    }

def check_data_availability(symbol: str, timeframe: str):
    """Check data availability for a symbol and timeframe."""
    try:
        db = get_database_operations(logger)
        latest_candle = db.market_data.get_latest_candle(symbol, timeframe)
        
        if latest_candle:
            latest_time = latest_candle['timestamp']
            time_diff = datetime.now(timezone.utc) - latest_time.replace(tzinfo=timezone.utc)
            
            return {
                'has_data': True,
                'latest_timestamp': latest_time,
                'time_since_last': time_diff,
                'is_recent': time_diff < timedelta(hours=1),
                'message': f"Latest data: {latest_time.strftime('%Y-%m-%d %H:%M:%S UTC')}"
            }
        else:
            return {
                'has_data': False,
                'latest_timestamp': None, 
                'time_since_last': None,
                'is_recent': False,
                'message': f"No data available for {symbol} {timeframe}"
            }
    except Exception as e:
        return {
            'has_data': False,
            'latest_timestamp': None, 
            'time_since_last': None,
            'is_recent': False,
            'message': f"Error checking data: {str(e)}"
        }

def create_data_status_indicator(symbol: str, timeframe: str):
    """Create a data status indicator for the dashboard."""
    status = check_data_availability(symbol, timeframe)
    
    if status['has_data']:
        if status['is_recent']:
            icon, color, status_text = "🟢", "#27ae60", "Real-time Data"
        else:
            icon, color, status_text = "🟡", "#f39c12", "Delayed Data"
    else:
        icon, color, status_text = "🔴", "#e74c3c", "No Data"
    
    return f'<span style="color: {color}; font-weight: bold;">{icon} {status_text}</span><br><small>{status["message"]}</small>'