"""
Service for chatbot functionality without database dependency.
"""

from typing import List, Dict, Any, Optional

class ChatbotService:
    """Service for chatbot functionality."""
    
    def __init__(self):
        """Initialize the chatbot service."""
        # In-memory storage for chat history
        self.chat_history = {}
        self.current_chat_id = 0
    
    def create_chat(self, user_id: str) -> int:
        """
        Create a new chat session.
        
        Args:
            user_id: ID of the user creating the chat.
            
        Returns:
            ID of the created chat.
        """
        self.current_chat_id += 1
        chat_id = self.current_chat_id
        
        self.chat_history[chat_id] = {
            'user_id': user_id,
            'messages': []
        }
        
        return chat_id
    
    def add_message(self, chat_id: int, content: str, is_user: bool = True) -> Dict[str, Any]:
        """
        Add a message to a chat.
        
        Args:
            chat_id: ID of the chat.
            content: Message content.
            is_user: Whether this is a user message (vs. bot message).
            
        Returns:
            Added message.
        """
        if chat_id not in self.chat_history:
            raise ValueError(f"Chat with ID {chat_id} not found")
        
        message = {
            'content': content,
            'is_user': is_user,
            'timestamp': self._get_timestamp()
        }
        
        self.chat_history[chat_id]['messages'].append(message)
        
        return message
    
    def get_chat_messages(self, chat_id: int) -> List[Dict[str, Any]]:
        """
        Get all messages for a chat.
        
        Args:
            chat_id: ID of the chat.
            
        Returns:
            List of messages.
        """
        if chat_id not in self.chat_history:
            raise ValueError(f"Chat with ID {chat_id} not found")
        
        return self.chat_history[chat_id]['messages']
    
    def get_response(self, chat_id: int, message: str) -> str:
        """
        Get a response from the chatbot.
        
        Args:
            chat_id: ID of the chat.
            message: User message.
            
        Returns:
            Bot response.
        """
        # Add user message to chat history
        self.add_message(chat_id, message, is_user=True)
        
        # Simple echo response for now
        response = f"You said: {message}"
        
        # Add bot response to chat history
        self.add_message(chat_id, response, is_user=False)
        
        return response
    
    def _get_timestamp(self) -> str:
        """Get current timestamp."""
        from datetime import datetime
        return datetime.utcnow().isoformat()


# Create a singleton instance
chatbot_service = ChatbotService()