import os
import sys
import re
import gradio as gr
import json
import tempfile
import base64
import io
from typing import List, Dict, Any, Optional, Tuple, Union
import logging
import pandas as pd
import plotly.express as px
import plotly.graph_objects as go
from plotly.subplots import make_subplots

try:
    # Intentar importar dependencias opcionales
    from langchain_community.agent_toolkits import create_sql_agent
    from langchain_community.agent_toolkits.sql.toolkit import SQLDatabaseToolkit
    from langchain_community.utilities import SQLDatabase
    from langchain_google_genai import ChatGoogleGenerativeAI
    from langchain.agents.agent_types import AgentType
    from langchain.memory import ConversationBufferWindowMemory
    from langchain_core.messages import AIMessage, HumanMessage, SystemMessage
    import pymysql
    from dotenv import load_dotenv
    
    DEPENDENCIES_AVAILABLE = True
except ImportError as e:
    logger.warning(f"Some dependencies are not available: {e}")
    DEPENDENCIES_AVAILABLE = False

# Configuración de logging
logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)

# Configure logging
logging.basicConfig(level=logging.INFO)

def generate_chart(data: Union[Dict, List[Dict], pd.DataFrame], 
                 chart_type: str, 
                 x: str, 
                 y: str = None, 
                 title: str = "", 
                 x_label: str = None, 
                 y_label: str = None) -> str:
    """
    Generate a chart from data and return it as a base64 encoded image.
    
    Args:
        data: The data to plot (can be a list of dicts or a pandas DataFrame)
        chart_type: Type of chart to generate (bar, line, pie, scatter, histogram)
        x: Column name for x-axis
        y: Column name for y-axis (not needed for pie charts)
        title: Chart title
        x_label: Label for x-axis
        y_label: Label for y-axis
        
    Returns:
        Markdown string with embedded image
    """
    try:
        # Convert data to DataFrame if it's a list of dicts
        if isinstance(data, list):
            df = pd.DataFrame(data)
        elif isinstance(data, dict):
            df = pd.DataFrame([data])
        else:
            df = data
            
        if not isinstance(df, pd.DataFrame):
            return "Error: Data must be a dictionary, list of dictionaries, or pandas DataFrame"
            
        # Generate the appropriate chart type
        fig = None
        if chart_type == 'bar':
            fig = px.bar(df, x=x, y=y, title=title)
        elif chart_type == 'line':
            fig = px.line(df, x=x, y=y, title=title)
        elif chart_type == 'pie':
            fig = px.pie(df, names=x, values=y, title=title)
        elif chart_type == 'scatter':
            fig = px.scatter(df, x=x, y=y, title=title)
        elif chart_type == 'histogram':
            fig = px.histogram(df, x=x, title=title)
        else:
            return "Error: Unsupported chart type. Use 'bar', 'line', 'pie', 'scatter', or 'histogram'"
        
        # Update layout
        fig.update_layout(
            xaxis_title=x_label or x,
            yaxis_title=y_label or (y if y != x else ''),
            title=title or f"{chart_type.capitalize()} Chart of {x} vs {y}" if y else f"{chart_type.capitalize()} Chart of {x}",
            template="plotly_white",
            margin=dict(l=20, r=20, t=40, b=20),
            height=400
        )
        
        # Save the figure to a temporary file
        temp_file = tempfile.NamedTemporaryFile(delete=False, suffix='.png')
        fig.write_image(temp_file.name, format='png', engine='kaleido')
        
        # Read the image file and encode as base64
        with open(temp_file.name, 'rb') as img_file:
            img_base64 = base64.b64encode(img_file.read()).decode('utf-8')
        
        # Clean up the temporary file
        os.unlink(temp_file.name)
        
        # Return as markdown image
        return f'<img src="data:image/png;base64,{img_base64}" style="max-width:100%;"/>'
        
    except Exception as e:
        error_msg = f"Error generating chart: {str(e)}"
        logger.error(error_msg, exc_info=True)
        return f"<div style='color: red;'>{error_msg}</div>"
logger = logging.getLogger(__name__)

def check_environment():
    """Verifica si el entorno está configurado correctamente."""
    if not DEPENDENCIES_AVAILABLE:
        return False, "Missing required Python packages. Please install them with: pip install -r requirements.txt"
    
    # Verificar si estamos en un entorno con variables de entorno
    required_vars = ["DB_USER", "DB_PASSWORD", "DB_HOST", "DB_NAME", "GOOGLE_API_KEY"]
    missing_vars = [var for var in required_vars if not os.getenv(var)]
    
    if missing_vars:
        return False, f"Missing required environment variables: {', '.join(missing_vars)}"
    
    return True, "Environment is properly configured"

def setup_database_connection():
    """Intenta establecer una conexión a la base de datos."""
    if not DEPENDENCIES_AVAILABLE:
        return None, "Dependencies not available"
        
    try:
        load_dotenv(override=True)
        
        # Debug: Log all environment variables (without sensitive values)
        logger.info("Environment variables:")
        for key, value in os.environ.items():
            if any(s in key.lower() for s in ['pass', 'key', 'secret']):
                logger.info(f"  {key}: {'*' * 8} (hidden for security)")
            else:
                logger.info(f"  {key}: {value}")
        
        db_user = os.getenv("DB_USER")
        db_password = os.getenv("DB_PASSWORD")
        db_host = os.getenv("DB_HOST")
        db_name = os.getenv("DB_NAME")
        
        # Debug: Log database connection info (without password)
        logger.info(f"Database connection attempt - Host: {db_host}, User: {db_user}, DB: {db_name}")
        if not all([db_user, db_password, db_host, db_name]):
            missing = [var for var, val in [
                ("DB_USER", db_user),
                ("DB_PASSWORD", "*" if db_password else ""),
                ("DB_HOST", db_host),
                ("DB_NAME", db_name)
            ] if not val]
            logger.error(f"Missing required database configuration: {', '.join(missing)}")
            return None, f"Missing database configuration: {', '.join(missing)}"
        
        if not all([db_user, db_password, db_host, db_name]):
            return None, "Missing database configuration"
            
        logger.info(f"Connecting to database: {db_user}@{db_host}/{db_name}")
        
        # Probar conexión
        connection = pymysql.connect(
            host=db_host,
            user=db_user,
            password=db_password,
            database=db_name,
            connect_timeout=5,
            cursorclass=pymysql.cursors.DictCursor
        )
        connection.close()
        
        # Si la conexión es exitosa, crear motor SQLAlchemy
        db_uri = f"mysql+pymysql://{db_user}:{db_password}@{db_host}/{db_name}"
        logger.info("Database connection successful")
        return SQLDatabase.from_uri(db_uri), ""
        
    except Exception as e:
        error_msg = f"Error connecting to database: {str(e)}"
        logger.error(error_msg)
        return None, error_msg

def initialize_llm():
    """Inicializa el modelo de lenguaje."""
    if not DEPENDENCIES_AVAILABLE:
        error_msg = "Dependencies not available. Make sure all required packages are installed."
        logger.error(error_msg)
        return None, error_msg
        
    google_api_key = os.getenv("GOOGLE_API_KEY")
    logger.info(f"GOOGLE_API_KEY found: {'Yes' if google_api_key else 'No'}")
    
    if not google_api_key:
        error_msg = "GOOGLE_API_KEY not found in environment variables. Please check your Hugging Face Space secrets."
        logger.error(error_msg)
        return None, error_msg
        
    try:
        logger.info("Initializing Google Generative AI...")
        llm = ChatGoogleGenerativeAI(
            model="gemini-2.0-flash",
            temperature=0,
            google_api_key=google_api_key,
            convert_system_message_to_human=True  # Convert system messages to human messages
        )
        
        # Test the model with a simple prompt
        test_prompt = "Hello, this is a test."
        logger.info(f"Testing model with prompt: {test_prompt}")
        test_response = llm.invoke(test_prompt)
        logger.info(f"Model test response: {str(test_response)[:100]}...")  # Log first 100 chars
        
        logger.info("Google Generative AI initialized successfully")
        return llm, ""
        
    except Exception as e:
        error_msg = f"Error initializing Google Generative AI: {str(e)}"
        logger.error(error_msg, exc_info=True)  # Include full stack trace
        return None, error_msg

def create_agent():
    """Crea el agente SQL si es posible."""
    if not DEPENDENCIES_AVAILABLE:
        error_msg = "Dependencies not available. Please check if all required packages are installed."
        logger.error(error_msg)
        return None, error_msg
    
    logger.info("Starting agent creation process...")
    
def create_agent(llm, db_connection):
    """Create and return a SQL database agent with conversation memory."""
    if not llm:
        error_msg = "Cannot create agent: LLM is not available"
        logger.error(error_msg)
        return None, error_msg
    
    if not db_connection:
        error_msg = "Cannot create agent: Database connection is not available"
        logger.error(error_msg)
        return None, error_msg
        
    try:
        logger.info("Creating SQL agent with memory...")
        
        # Create conversation memory
        memory = ConversationBufferWindowMemory(
            memory_key="chat_history",
            k=5,  # Keep last 5 message exchanges in memory
            return_messages=True,
            output_key="output"
        )
        
        # Create the database toolkit with additional configuration
        toolkit = SQLDatabaseToolkit(
            db=db_connection,
            llm=llm
        )
        
        # Create the agent with memory and more detailed configuration
        agent = create_sql_agent(
            llm=llm,
            toolkit=toolkit,
            agent_type=AgentType.OPENAI_FUNCTIONS,
            verbose=True,
            handle_parsing_errors=True,  # Better error handling for parsing
            max_iterations=10,  # Limit the number of iterations
            early_stopping_method="generate",  # Stop early if the agent is stuck
            memory=memory,  # Add memory to the agent
            return_intermediate_steps=True  # Important for memory to work properly
        )
        
        # Test the agent with a simple query
        logger.info("Testing agent with a simple query...")
        try:
            test_query = "SELECT 1"
            test_result = agent.run(test_query)
            logger.info(f"Agent test query successful: {str(test_result)[:200]}...")
        except Exception as e:
            logger.warning(f"Agent test query failed (this might be expected): {str(e)}")
            # Continue even if test fails, as it might be due to model limitations
        
        logger.info("SQL agent created successfully")
        return agent, ""
        
    except Exception as e:
        error_msg = f"Error creating SQL agent: {str(e)}"
        logger.error(error_msg, exc_info=True)
        return None, error_msg

# Inicializar el agente
logger.info("="*50)
logger.info("Starting application initialization...")
logger.info(f"Python version: {sys.version}")
logger.info(f"Current working directory: {os.getcwd()}")
logger.info(f"Files in working directory: {os.listdir()}")

# Verificar las variables de entorno
logger.info("Checking environment variables...")
for var in ["DB_USER", "DB_PASSWORD", "DB_HOST", "DB_NAME", "GOOGLE_API_KEY"]:
    logger.info(f"{var}: {'*' * 8 if os.getenv(var) else 'NOT SET'}")

# Initialize components
logger.info("Initializing database connection...")
db_connection, db_error = setup_database_connection()
if db_error:
    logger.error(f"Failed to initialize database: {db_error}")

logger.info("Initializing language model...")
llm, llm_error = initialize_llm()
if llm_error:
    logger.error(f"Failed to initialize language model: {llm_error}")

logger.info("Initializing agent...")
agent, agent_error = create_agent(llm, db_connection)
db_connected = agent is not None

if agent:
    logger.info("Agent initialized successfully")
else:
    logger.error(f"Failed to initialize agent: {agent_error}")

logger.info("="*50)

def extract_sql_query(text):
    """Extrae consultas SQL del texto usando expresiones regulares."""
    if not text:
        return None
    
    # Buscar código SQL entre backticks
    sql_match = re.search(r'```(?:sql)?\s*(.*?)```', text, re.DOTALL)
    if sql_match:
        return sql_match.group(1).strip()
    
    # Si no hay backticks, buscar una consulta SQL simple
    sql_match = re.search(r'(SELECT|INSERT|UPDATE|DELETE|CREATE|ALTER|DROP|TRUNCATE).*?;', text, re.IGNORECASE | re.DOTALL)
    if sql_match:
        return sql_match.group(0).strip()
    
    return None

def execute_sql_query(query, db_connection):
    """Ejecuta una consulta SQL y devuelve los resultados como una cadena."""
    if not db_connection:
        return "Error: No hay conexión a la base de datos"
        
    try:
        with db_connection._engine.connect() as connection:
            result = connection.execute(query)
            rows = result.fetchall()
            
            # Convertir los resultados a un formato legible
            if not rows:
                return "La consulta no devolvió resultados"
                
            # Si es un solo resultado, devolverlo directamente
            if len(rows) == 1 and len(rows[0]) == 1:
                return str(rows[0][0])
                
            # Si hay múltiples filas, formatear como tabla
            try:
                import pandas as pd
                df = pd.DataFrame(rows)
                return df.to_markdown(index=False)
            except ImportError:
                # Si pandas no está disponible, usar formato simple
                return "\n".join([str(row) for row in rows])
                
    except Exception as e:
        return f"Error ejecutando la consulta: {str(e)}"

def generate_plot(data, x_col, y_col, title, x_label, y_label):
    """Generate a plot from data and return the file path."""
    plt.figure(figsize=(10, 6))
    plt.bar(data[x_col], data[y_col])
    plt.title(title)
    plt.xlabel(x_label)
    plt.ylabel(y_label)
    plt.xticks(rotation=45)
    plt.tight_layout()
    
    # Save to a temporary file
    temp_dir = tempfile.mkdtemp()
    plot_path = os.path.join(temp_dir, "plot.png")
    plt.savefig(plot_path)
    plt.close()
    
    return plot_path

def convert_to_messages_format(chat_history):
    """Convert chat history to the format expected by Gradio 5.x"""
    if not chat_history:
        return []
        
    messages = []
    
    # If the first element is a list, assume it's in the old format
    if isinstance(chat_history[0], list):
        for msg in chat_history:
            if isinstance(msg, list) and len(msg) == 2:
                # Format: [user_msg, bot_msg]
                user_msg, bot_msg = msg
                if user_msg:
                    messages.append({"role": "user", "content": user_msg})
                if bot_msg:
                    messages.append({"role": "assistant", "content": bot_msg})
    else:
        # Assume it's already in the correct format or can be used as is
        for msg in chat_history:
            if isinstance(msg, dict) and "role" in msg and "content" in msg:
                messages.append(msg)
            elif isinstance(msg, str):
                # If it's a string, assume it's a user message
                messages.append({"role": "user", "content": msg})
    
    return messages

async def stream_agent_response(question: str, chat_history: List) -> List[Dict]:
    """Procesa la pregunta del usuario y devuelve la respuesta del agente con memoria de conversación."""
    global agent  # Make sure we can modify the agent's memory
    
    # Initialize response
    response_text = ""
    messages = []
    
    # Add previous chat history in the correct format for the agent
    if chat_history:
        # Convert chat history to the format expected by the agent's memory
        for msg in chat_history:
            if msg["role"] == "user":
                messages.append(HumanMessage(content=msg["content"]))
            elif msg["role"] == "assistant":
                messages.append(AIMessage(content=msg["content"]))
    
    # Add current user's question
    user_message = HumanMessage(content=question)
    messages.append(user_message)
    
    if not agent:
        error_msg = (
            "## ⚠️ Error: Agente no inicializado\n\n"
            "No se pudo inicializar el agente de base de datos. Por favor, verifica que:\n"
            "1. Todas las variables de entorno estén configuradas correctamente\n"
            "2. La base de datos esté accesible\n"
            f"3. El modelo de lenguaje esté disponible\n\n"
            f"Error: {agent_error}"
        )
        assistant_message = {"role": "assistant", "content": error_msg}
        return [assistant_message]
        
    # Update the agent's memory with the full conversation history
    try:
        # Clear existing memory
        if hasattr(agent, 'memory') and agent.memory is not None:
            agent.memory.clear()
            
        # Add all messages to memory
        for i in range(0, len(messages)-1, 2):  # Process in pairs (user, assistant)
            if i+1 < len(messages):
                agent.memory.save_context(
                    {"input": messages[i].content},
                    {"output": messages[i+1].content}
                )
    except Exception as e:
        logger.error(f"Error updating agent memory: {str(e)}", exc_info=True)
    
    try:
        # Add empty assistant message that will be updated
        assistant_message = {"role": "assistant", "content": ""}
        messages.append(assistant_message)
        
        # Execute the agent with proper error handling
        try:
            response = await agent.ainvoke({"input": question, "chat_history": chat_history})
            logger.info(f"Agent response type: {type(response)}")
            logger.info(f"Agent response content: {str(response)[:500]}...")
            
            # Handle different response formats
            if hasattr(response, 'output') and response.output:
                response_text = response.output
            elif isinstance(response, str):
                response_text = response
            elif hasattr(response, 'get') and callable(response.get) and 'output' in response:
                response_text = response['output']
            else:
                response_text = str(response)
            
            logger.info(f"Extracted response text: {response_text[:200]}...")
            
            # Check if the response contains an SQL query
            sql_query = extract_sql_query(response_text)
            if sql_query:
                logger.info(f"Detected SQL query: {sql_query}")
                # Execute the query and update the response
                db_connection, _ = setup_database_connection()
                if db_connection:
                    query_result = execute_sql_query(sql_query, db_connection)
                    
                    # Add the query and its result to the response
                    response_text += f"\n\n### 🔍 Resultado de la consulta:\n```sql\n{sql_query}\n```\n\n{query_result}"
                    
                    # Try to generate a chart if the result is tabular
                    try:
                        if isinstance(query_result, str) and '|' in query_result and '---' in query_result:
                            # Convert markdown table to DataFrame
                            from io import StringIO
                            import re
                            
                            # Clean up the markdown table
                            lines = [line.strip() for line in query_result.split('\n') 
                                    if line.strip() and '---' not in line and '|' in line]
                            if len(lines) > 1:  # At least header + 1 data row
                                # Get column names from the first line
                                columns = [col.strip() for col in lines[0].split('|')[1:-1]]
                                # Get data rows
                                data = []
                                for line in lines[1:]:
                                    values = [val.strip() for val in line.split('|')[1:-1]]
                                    if len(values) == len(columns):
                                        data.append(dict(zip(columns, values)))
                                
                                if data and len(columns) >= 2:
                                    # Generate a chart based on the data
                                    chart_type = 'bar'  # Default chart type
                                    if len(columns) == 2:
                                        # Simple bar chart for two columns
                                        chart_html = generate_chart(
                                            data=data,
                                            chart_type=chart_type,
                                            x=columns[0],
                                            y=columns[1],
                                            title=f"{columns[1]} por {columns[0]}",
                                            x_label=columns[0],
                                            y_label=columns[1]
                                        )
                                        response_text += f"\n\n### 📊 Visualización:\n{chart_html}"
                                    elif len(columns) > 2:
                                        # For multiple columns, create a line chart
                                        chart_html = generate_chart(
                                            data=data,
                                            chart_type='line',
                                            x=columns[0],
                                            y=columns[1],
                                            title=f"{', '.join(columns[1:])} por {columns[0]}",
                                            x_label=columns[0],
                                            y_label=", ".join(columns[1:])
                                        )
                                        response_text += f"\n\n### 📊 Visualización:\n{chart_html}"
                    except Exception as e:
                        logger.error(f"Error generating chart: {str(e)}", exc_info=True)
                        # Don't fail the whole request if chart generation fails
                        response_text += "\n\n⚠️ No se pudo generar la visualización de los datos."
                else:
                    response_text += "\n\n⚠️ No se pudo conectar a la base de datos para ejecutar la consulta."
            
            # Update the assistant's message with the response
            assistant_message["content"] = response_text
            
        except Exception as e:
            error_msg = f"Error al ejecutar el agente: {str(e)}"
            logger.error(error_msg, exc_info=True)
            assistant_message["content"] = f"## ❌ Error\n\n{error_msg}"
        
        # Return the message in the correct format for Gradio Chatbot
        # Format: [(user_message, assistant_message)]
        return [(None, assistant_message["content"])]
        
    except Exception as e:
        error_msg = f"## ❌ Error\n\nOcurrió un error al procesar tu solicitud:\n\n```\n{str(e)}\n```"
        if "assistant_message" in locals():
            assistant_message["content"] = error_msg
        else:
            assistant_message = {"role": "assistant", "content": error_msg}
        
        logger.error(f"Error in stream_agent_response: {str(e)}", exc_info=True)
        return [assistant_message]

# Custom CSS for the app
custom_css = """
.gradio-container {
    max-width: 1200px !important;
    margin: 0 auto !important;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
}

#chatbot {
    min-height: 500px;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    margin-bottom: 20px;
    padding: 20px;
    background-color: #f9f9f9;
}

.user-message, .bot-message {
    padding: 12px 16px;
    border-radius: 18px;
    margin: 8px 0;
    max-width: 80%;
    line-height: 1.5;
}

.user-message {
    background-color: #007bff;
    color: white;
    margin-left: auto;
    border-bottom-right-radius: 4px;
}

.bot-message {
    background-color: #f1f1f1;
    color: #333;
    margin-right: auto;
    border-bottom-left-radius: 4px;
}

#question-input textarea {
    min-height: 50px !important;
    border-radius: 8px !important;
    padding: 12px !important;
    font-size: 16px !important;
}

#send-button {
    height: 100%;
    background-color: #007bff !important;
    color: white !important;
    border: none !important;
    border-radius: 8px !important;
    font-weight: 500 !important;
    transition: background-color 0.2s !important;
}

#send-button:hover {
    background-color: #0056b3 !important;
}

.status-message {
    text-align: center;
    color: #666;
    font-style: italic;
    margin: 10px 0;
}
"""

def create_ui():
    """Crea y devuelve los componentes de la interfaz de usuario de Gradio."""
    # Verificar el estado del entorno
    env_ok, env_message = check_environment()
    
    # Crear el tema personalizado
    theme = gr.themes.Soft(
        primary_hue="blue",
        secondary_hue="indigo",
        neutral_hue="slate"
    )
    
    with gr.Blocks(
        css=custom_css,
        title="Asistente de Base de Datos SQL",
        theme=theme
    ) as demo:
        # Encabezado
        gr.Markdown("""
        # 🤖 Asistente de Base de Datos SQL
        
        Haz preguntas en lenguaje natural sobre tu base de datos y obtén resultados de consultas SQL.
        """)
        
        # Mensaje de estado
        if not env_ok:
            gr.Warning("⚠️ " + env_message)
        
        # Create the chat interface
        with gr.Row():
            chatbot = gr.Chatbot(
                [],
                elem_id="chatbot",
                bubble_full_width=False,
                avatar_images=(
                    None,
                    (os.path.join(os.path.dirname(__file__), "logo.png")),
                ),
                height=600,
                render_markdown=True,  # Enable markdown rendering
                show_label=False,
                show_share_button=False
            )
        
        # Input area
        with gr.Row():
            question_input = gr.Textbox(
                label="",
                placeholder="Escribe tu pregunta aquí...",
                container=False,
                scale=5,
                min_width=300,
                max_lines=3,
                autofocus=True,
                elem_id="question-input"
            )
            submit_button = gr.Button(
                "Enviar",
                variant="primary",
                min_width=100,
                scale=1,
                elem_id="send-button"
            )
        
        # System status
        with gr.Accordion("ℹ️ Estado del sistema", open=not env_ok):
            if not DEPENDENCIES_AVAILABLE:
                gr.Markdown("""
                ## ❌ Dependencias faltantes
                
                Para ejecutar esta aplicación localmente, necesitas instalar las dependencias:
                
                ```bash
                pip install -r requirements.txt
                ```
                """)
            else:
                if not agent:
                    gr.Markdown(f"""
                    ## ⚠️ Configuración incompleta
                    
                    No se pudo inicializar el agente de base de datos. Por favor, verifica que:
                    
                    1. Todas las variables de entorno estén configuradas correctamente
                    2. La base de datos esté accesible
                    3. La API de Google Gemini esté configurada
                    
                    **Error:** {agent_error if agent_error else 'No se pudo determinar el error'}
                    
                    ### Configuración local
                    
                    Crea un archivo `.env` en la raíz del proyecto con las siguientes variables:
                    
                    ```
                    DB_USER=tu_usuario
                    DB_PASSWORD=tu_contraseña
                    DB_HOST=tu_servidor
                    DB_NAME=tu_base_de_datos
                    GOOGLE_API_KEY=tu_api_key_de_google
                    ```
                    """)
                else:
                    if os.getenv('SPACE_ID'):
                        # Modo demo en Hugging Face Spaces
                        gr.Markdown("""
                        ## 🚀 Modo Demo
                        
                        Esta es una demostración del asistente de base de datos SQL. Para usar la versión completa con conexión a base de datos:
                        
                        1. Clona este espacio en tu cuenta de Hugging Face
                        2. Configura las variables de entorno en la configuración del espacio:
                           - `DB_USER`: Tu usuario de base de datos
                           - `DB_PASSWORD`: Tu contraseña de base de datos
                           - `DB_HOST`: La dirección del servidor de base de datos
                           - `DB_NAME`: El nombre de la base de datos
                           - `GOOGLE_API_KEY`: Tu clave de API de Google Gemini
                        
                        **Nota:** Actualmente estás en modo de solo demostración.
                        """)
                    else:
                        gr.Markdown("""
                        ## ✅ Sistema listo
                        
                        El asistente está listo para responder tus preguntas sobre la base de datos.
                        """)
        
        # Hidden component for streaming output
        streaming_output_display = gr.Textbox(visible=False)
        
        return demo, chatbot, question_input, submit_button, streaming_output_display

def create_application():
    """Create and configure the Gradio application."""
    # Create the UI components
    demo, chatbot, question_input, submit_button, streaming_output_display = create_ui()
    
    def user_message(user_input: str, chat_history: List[Dict]) -> Tuple[str, List[Dict]]:
        """Add user message to chat history and clear input."""
        if not user_input.strip():
            return "", chat_history
            
        logger.info(f"User message: {user_input}")
        
        # Initialize chat history if needed
        if chat_history is None:
            chat_history = []
        
        # Add user message
        chat_history.append({"role": "user", "content": user_input})
        
        # Add empty assistant response
        chat_history.append({"role": "assistant", "content": ""})
        
        # Clear the input
        return "", chat_history
    
    async def bot_response(chat_history: List[Dict]) -> List[Dict]:
        """Get bot response and update chat history."""
        if not chat_history or chat_history[-1]["role"] != "assistant":
            return chat_history
        
        try:
            # Get the user's question (second to last message)
            if len(chat_history) < 2:
                return chat_history
                
            question = chat_history[-2]["content"]
            logger.info(f"Processing question: {question}")
            
            # Call the agent and get the response
            response = await stream_agent_response(question, chat_history[:-2])
            
            if isinstance(response, list):
                for msg in response:
                    if msg["role"] == "assistant":
                        # Update the assistant's response
                        chat_history[-1] = msg
            
            logger.info("Response generation complete")
            return chat_history
            
        except Exception as e:
            error_msg = f"Error al procesar la solicitud: {str(e)}"
            logger.error(error_msg, exc_info=True)
            chat_history[-1]["content"] = error_msg
            return chat_history
    
    # Event handlers
    with demo:
        # Handle form submission
        msg_submit = question_input.submit(
            fn=user_message,
            inputs=[question_input, chatbot],
            outputs=[question_input, chatbot],
            queue=True
        ).then(
            fn=bot_response,
            inputs=[chatbot],
            outputs=[chatbot],
            api_name="ask"
        )
        
        # Handle button click
        btn_click = submit_button.click(
            fn=user_message,
            inputs=[question_input, chatbot],
            outputs=[question_input, chatbot],
            queue=True
        ).then(
            fn=bot_response,
            inputs=[chatbot],
            outputs=[chatbot]
        )
    
    return demo

# Create the application
demo = create_application()

# Configuración para Hugging Face Spaces
def get_app():
    """Obtiene la instancia de la aplicación Gradio para Hugging Face Spaces."""
    # Verificar si estamos en un entorno de Hugging Face Spaces
    if os.getenv('SPACE_ID'):
        # Configuración específica para Spaces
        demo.title = "🤖 Asistente de Base de Datos SQL (Demo)"
        demo.description = """
        Este es un demo del asistente de base de datos SQL. 
        Para usar la versión completa con conexión a base de datos, clona este espacio y configura las variables de entorno.
        """
    
    return demo

# Para desarrollo local
if __name__ == "__main__":
    # Configuración para desarrollo local - versión simplificada para Gradio 5.x
    demo.launch(
        server_name="0.0.0.0",
        server_port=7860,
        debug=True,
        share=False
    )