"""
Feature Flag Service for managing application features
"""
import os
from typing import Dict, List, Any
from app.core.config import settings


class FeatureFlagService:
    """Service for managing feature flags"""
    
    def __init__(self):
        """Initialize feature flags from environment variables"""
        self._flags = self._load_flags_from_env()
    
    def _load_flags_from_env(self) -> Dict[str, Any]:
        """Load feature flags from environment variables"""
        # Get the FEATURE_FLAGS environment variable (comma-separated list)
        feature_flags_env = os.getenv("FEATURE_FLAGS", "")
        
        # Default feature flags - these can be overridden by environment
        default_flags = {
            "CASH_PAYMENT_ENABLED": True,
            "EMAIL_NOTIFICATIONS_ENABLED": True,
            "EVENT_MANAGEMENT_ENABLED": True,
            "AUTO_RENEWAL_ENABLED": False,
            "MEMBERSHIP_TRANSFERS_ENABLED": False,
            "BULK_OPERATIONS_ENABLED": False,
            "ADVANCED_REPORTING_ENABLED": False,
            "API_RATE_LIMITING_ENABLED": True,
        }
        
        # Parse environment variable
        flags = default_flags.copy()
        
        if feature_flags_env:
            # Parse comma-separated key=value pairs
            for flag_pair in feature_flags_env.split(","):
                flag_pair = flag_pair.strip()
                if "=" in flag_pair:
                    key, value = flag_pair.split("=", 1)
                    key = key.strip().upper()
                    value = value.strip().lower()
                    
                    # Convert string to boolean
                    if value in ("true", "1", "yes", "on"):
                        flags[key] = True
                    elif value in ("false", "0", "no", "off"):
                        flags[key] = False
                    else:
                        # For non-boolean values, keep as string
                        flags[key] = value
        
        return flags
    
    def is_enabled(self, flag_name: str) -> bool:
        """Check if a feature flag is enabled"""
        flag_name = flag_name.upper()
        return bool(self._flags.get(flag_name, False))
    
    def get_flag_value(self, flag_name: str, default: Any = None) -> Any:
        """Get the value of a feature flag"""
        flag_name = flag_name.upper()
        return self._flags.get(flag_name, default)
    
    def get_all_flags(self) -> Dict[str, Any]:
        """Get all feature flags"""
        return self._flags.copy()
    
    def get_enabled_flags(self) -> List[str]:
        """Get list of enabled feature flag names"""
        return [name for name, value in self._flags.items() if value is True]
    
    def reload_flags(self) -> None:
        """Reload feature flags from environment (useful for runtime updates)"""
        self._flags = self._load_flags_from_env()


# Global instance
feature_flags = FeatureFlagService()