from flask import Flask, render_template, request, Response
import requests
import datetime
from twilio.rest import Client  # For Twilio integration
from geopy.geocoders import Photon
from geopy.exc import GeocoderTimedOut, GeocoderServiceError

app = Flask(__name__)

# Initialize Photon geocoder (no API key required)
photon_geolocator = Photon(user_agent="MyWeatherApp", timeout=10)

def parse_iso_datetime(timestr):
    """
    Parse an ISO8601 datetime string (removing any trailing 'Z').
    """
    if timestr.endswith("Z"):
        timestr = timestr[:-1]
    return datetime.datetime.fromisoformat(timestr)

def find_closest_hour_index(hour_times, current_time_str):
    """
    Find the index in hour_times that is closest to the current_time_str.
    """
    if not hour_times:
        return None
    dt_current = parse_iso_datetime(current_time_str)
    min_diff = None
    best_index = None
    for i, ht in enumerate(hour_times):
        dt_ht = parse_iso_datetime(ht)
        diff = abs((dt_ht - dt_current).total_seconds())
        if min_diff is None or diff < min_diff:
            min_diff = diff
            best_index = i
    return best_index

def get_weather_icon(code):
    """Map the Open-Meteo weathercode to an emoji icon."""
    if code == 0:
        return "☀️"  # Clear sky
    elif code in [1, 2, 3]:
        return "⛅"
    elif code in [45, 48]:
        return "🌫️"
    elif code in [51, 53, 55]:
        return "🌦️"
    elif code in [56, 57]:
        return "🌧️"
    elif code in [61, 63, 65]:
        return "🌧️"
    elif code in [66, 67]:
        return "🌧️"
    elif code in [71, 73, 75, 77]:
        return "❄️"
    elif code in [80, 81, 82]:
        return "🌦️"
    elif code in [85, 86]:
        return "❄️"
    elif code in [95, 96, 99]:
        return "⛈️"
    else:
        return "❓"

def get_weather_description(code):
    """Short textual description for the weathercode."""
    descriptions = {
        0: "Clear sky",
        1: "Mainly clear",
        2: "Partly cloudy",
        3: "Overcast",
        45: "Fog",
        48: "Depositing rime fog",
        51: "Light drizzle",
        53: "Moderate drizzle",
        55: "Dense drizzle",
        56: "Freezing drizzle",
        57: "Freezing drizzle",
        61: "Slight rain",
        63: "Moderate rain",
        65: "Heavy rain",
        66: "Freezing rain",
        67: "Freezing rain",
        71: "Slight snow fall",
        73: "Moderate snow fall",
        75: "Heavy snow fall",
        77: "Snow grains",
        80: "Slight rain showers",
        81: "Moderate rain showers",
        82: "Violent rain showers",
        85: "Slight snow showers",
        86: "Heavy snow showers",
        95: "Thunderstorm",
        96: "Thunderstorm w/ slight hail",
        99: "Thunderstorm w/ heavy hail"
    }
    return descriptions.get(code, "Unknown")

def reverse_geocode(lat, lon):
    """
    Use Photon (via geopy) to convert latitude and longitude into a human-readable address.
    If the geocoding fails, returns a fallback string with the coordinates.
    """
    try:
        location = photon_geolocator.reverse((lat, lon), exactly_one=True)
        if location:
            return location.address
    except (GeocoderTimedOut, GeocoderServiceError) as e:
        print("Photon reverse geocode error:", e)
    return f"Lat: {lat}, Lon: {lon}"

# -----------------------------
# Twilio WhatsApp Integration
# -----------------------------
def check_and_collect_alerts(forecast_list):
    """
    Check the forecast for hazardous weather conditions and collect alert messages.
    """
    alerts = []
    for day in forecast_list:
        if day.get("tmax") and day.get("tmax") > 40:
            alerts.append(f"{day['day_name']} ({day['date_str']}): Extreme heat. Please take necessary precautions.")
        elif day.get("desc") and any(keyword in day['desc'].lower() for keyword in ["rain", "drizzle", "overcast", "thunderstorm"]):
            alerts.append(f"{day['day_name']} ({day['date_str']}): {day['desc']}. Please take necessary precautions.")
    return alerts

def send_whatsapp_message(message, location, location_address):
    """
    Send a WhatsApp message using Twilio API.
    """
    google_maps_url = f"https://www.google.com/maps?q={location[0]},{location[1]}"
    message_content = (
        f"Weather Alerts for Your Farm :\n"
        f"{message}\n"
        f"Location (lat, lon): {location[0]}, {location[1]}\n"
        f"Location: {location_address}\n"
        f"Map: {google_maps_url}"
    )
    account_sid = 'AC490e071f8d01bf0df2f03d086c788d87'
    auth_token = '224b23b950ad5a4052aba15893fdf083'
    client = Client(account_sid, auth_token)
    msg = client.messages.create(
        from_='whatsapp:+14155238886',
        body=message_content,
        to='whatsapp:+917559355282'
    )
    print("Twilio Message SID:", msg.sid)

@app.route("/", methods=["GET", "POST"])
def index():
    # Default coordinates
    default_lat = 18.5196
    default_lon = 73.8553

    if request.method == "POST":
        try:
            lat = float(request.form.get("lat", default_lat))
            lon = float(request.form.get("lon", default_lon))
        except ValueError:
            lat, lon = default_lat, default_lon
    else:
        lat = float(request.args.get("lat", default_lat))
        lon = float(request.args.get("lon", default_lon))

    location_address = reverse_geocode(lat, lon)

    # Call Open-Meteo API for forecast data
    url = "https://api.open-meteo.com/v1/forecast"
    params = {
        "latitude": lat,
        "longitude": lon,
        "hourly": (
            "temperature_2m,relative_humidity_2m,precipitation,"
            "cloudcover,windspeed_10m,pressure_msl,soil_moisture_3_to_9cm,uv_index"
        ),
        "daily": (
            "weathercode,temperature_2m_max,temperature_2m_min,"
            "sunrise,sunset,uv_index_max"
        ),
        "current_weather": True,
        "forecast_days": 14,
        "timezone": "auto"
    }
    resp = requests.get(url, params=params)
    data = resp.json()

    timezone = data.get("timezone", "Local")
    current_weather = data.get("current_weather", {})
    current_temp = current_weather.get("temperature")
    current_time = current_weather.get("time")
    current_code = current_weather.get("weathercode")
    current_icon = get_weather_icon(current_code)
    current_desc = get_weather_description(current_code)
    current_wind_speed = current_weather.get("windspeed", 0.0)
    current_wind_dir = current_weather.get("winddirection", 0)

    if current_time:
        dt_current = parse_iso_datetime(current_time)
        current_time_formatted = dt_current.strftime("%A, %b %d, %Y %I:%M %p")
    else:
        current_time_formatted = ""

    hourly_data = data.get("hourly", {})
    hour_times = hourly_data.get("time", [])
    hour_temp = hourly_data.get("temperature_2m", [])
    hour_humidity = hourly_data.get("relative_humidity_2m", [])
    hour_precip = hourly_data.get("precipitation", [])
    hour_clouds = hourly_data.get("cloudcover", [])
    hour_wind = hourly_data.get("windspeed_10m", [])
    hour_pressure = hourly_data.get("pressure_msl", [])
    hour_soil = hourly_data.get("soil_moisture_3_to_9cm", [])
    hour_uv = hourly_data.get("uv_index", [])

    current_index = None
    if current_time:
        current_index = find_closest_hour_index(hour_times, current_time)

    feels_like = current_temp
    if current_index is not None and current_index < len(hour_humidity):
        h = hour_humidity[current_index]
        feels_like = round(current_temp - 0.2 * (100 - h) / 10, 1)

    today_highlights = {}
    if current_index is not None:
        today_highlights["humidity"] = hour_humidity[current_index] if current_index < len(hour_humidity) else None
        today_highlights["precipitation"] = hour_precip[current_index] if current_index < len(hour_precip) else None
        today_highlights["clouds"] = hour_clouds[current_index] if current_index < len(hour_clouds) else None
        today_highlights["windspeed"] = hour_wind[current_index] if current_index < len(hour_wind) else None
        today_highlights["pressure"] = hour_pressure[current_index] if current_index < len(hour_pressure) else None
        today_highlights["soil_moisture"] = hour_soil[current_index] if current_index < len(hour_soil) else None
        today_highlights["uv_index"] = hour_uv[current_index] if current_index < len(hour_uv) else None
    else:
        for k in ["humidity", "precipitation", "cloudcover", "windspeed", "pressure", "soil_moisture", "uv_index"]:
            today_highlights[k] = None

    daily_data = data.get("daily", {})
    daily_sunrise = daily_data.get("sunrise", [])
    daily_sunset = daily_data.get("sunset", [])
    if len(daily_sunrise) > 0:
        today_highlights["sunrise"] = daily_sunrise[0][11:16]
    else:
        today_highlights["sunrise"] = None
    if len(daily_sunset) > 0:
        today_highlights["sunset"] = daily_sunset[0][11:16]
    else:
        today_highlights["sunset"] = None

    daily_times = daily_data.get("time", [])
    daily_codes = daily_data.get("weathercode", [])
    daily_tmax = daily_data.get("temperature_2m_max", [])
    daily_tmin = daily_data.get("temperature_2m_min", [])
    forecast_list = []

    def get_hour_temp(date_str, hour_str):
        target = date_str + "T" + hour_str + ":00"
        best_idx = None
        best_diff = None
        dt_target = parse_iso_datetime(target)
        for i, ht in enumerate(hour_times):
            dt_ht = parse_iso_datetime(ht)
            diff = abs((dt_ht - dt_target).total_seconds())
            if best_diff is None or diff < best_diff:
                best_diff = diff
                best_idx = i
        if best_idx is not None and best_idx < len(hour_temp):
            return hour_temp[best_idx]
        return None

    for i in range(len(daily_times)):
        date_str = daily_times[i]
        dt_obj = parse_iso_datetime(date_str)
        day_name = dt_obj.strftime("%A")
        short_date = dt_obj.strftime("%b %d")

        code = daily_codes[i] if i < len(daily_codes) else None
        icon = get_weather_icon(code)
        desc = get_weather_description(code)

        tmax = daily_tmax[i] if i < len(daily_tmax) else None
        tmin = daily_tmin[i] if i < len(daily_tmin) else None
        avg_temp = round((tmax + tmin) / 2, 1) if tmax is not None and tmin is not None else None

        morning_temp = get_hour_temp(date_str, "09")
        evening_temp = get_hour_temp(date_str, "21")

        sr = daily_sunrise[i][11:16] if i < len(daily_sunrise) else None
        ss = daily_sunset[i][11:16] if i < len(daily_sunset) else None

        forecast_list.append({
            "day_name": day_name,
            "date_str": short_date,
            "icon": icon,
            "desc": desc,
            "avg_temp": avg_temp,
            "morning_temp": morning_temp,
            "evening_temp": evening_temp,
            "sunrise": sr,
            "sunset": ss,
            "tmax": tmax,
            "tmin": tmin
        })

    alerts = check_and_collect_alerts(forecast_list)
    if alerts:
        alert_message = "\n".join(alerts)
        send_whatsapp_message(alert_message, (lat, lon), location_address)
        alerts_sent = True
    else:
        alerts_sent = False

    return render_template(
        "index.html",
        lat=lat,
        lon=lon,
        location_address=location_address,
        current_temp=current_temp,
        current_icon=current_icon,
        current_desc=current_desc,
        current_time=current_time_formatted,
        current_wind_speed=current_wind_speed,
        current_wind_dir=current_wind_dir,
        feels_like=feels_like,
        today_highlights=today_highlights,
        forecast_list=forecast_list,
        timezone=timezone,
        alerts_sent=alerts_sent
    )

if __name__ == "__main__":
    app.run(debug=True)