from smolagents.tools import tool
import requests
import os
import re
from typing import Optional

@tool
def get_weather(location: str) -> str:
    """Get the current weather for a specified location.
    Args:
        location: A string representing a city (e.g., 'New York', 'Paris').
    Returns:
        str: A json blob containing the current weather information for that city.
    """
    # Validate that location contains only allowed characters: letters, digits, spaces, and hyphens
    if not re.fullmatch(r'[A-Za-z0-9\s-]+', location):
        return "Error: Location contains invalid characters. Only letters, digits, spaces, and hyphens are allowed."
    try:
        # Get the API key from environment variables
        api_key = os.getenv('OPENWEATHERMAP_API_KEY')
        if not api_key:
            return "Error: OPENWEATHERMAP_API_KEY not set in environment variables."

        # First, geocode the location to get latitude and longitude
        geo_url = f"http://api.openweathermap.org/geo/1.0/direct?q={location}&limit=1&appid={api_key}"
        geo_response = requests.get(geo_url)
        geo_data = geo_response.json()
        if not geo_data:
            return f"Error: Could not geocode location '{location}'."
        lat = geo_data[0].get('lat')
        lon = geo_data[0].get('lon')
        if lat is None or lon is None:
            return f"Error: Latitude or longitude not found for location '{location}'."

        # Call the OpenWeatherMap weather API 2.5 endpoint
        weather_url = f"https://api.openweathermap.org/data/2.5/weather?lat={lat}&lon={lon}&appid={api_key}&units=imperial"
        weather_response = requests.get(weather_url)
        weather_data = weather_response.json()

        if weather_response.status_code == 200:
            temp = weather_data.get('main', {}).get('temp', 'N/A')
            weather_desc = weather_data.get('weather', [{}])[0].get('description', 'N/A')
            humidity = weather_data.get('main', {}).get('humidity', 'N/A')
            wind_speed = weather_data.get('wind', {}).get('speed', 'N/A')
            return f"The current weather in {location} is {temp}°F with {weather_desc}. Humidity: {humidity}%, Wind speed: {wind_speed} mph."
        else:
            return f"Error fetching weather for {location}: {weather_data.get('message', 'Unknown error')}"
    except Exception as e:
        return f"Error fetching weather for {location}: {str(e)}"