import streamlit as st
import json
import pandas as pd
import requests

def get_coordinates(address: str, api_key: str) -> list:
    """
    Get the coordinates (latitude and longitude) of an address using the OpenCage Data Geocoding API.

    Parameters:
    address (str): The address to geocode.
    api_key (str): Your OpenCage Data API key.

    Returns:
    list: A list containing the latitude and longitude of the address.
    """
    # Encode the address for the URL
    encoded_address = requests.utils.quote(address)
    
    # Construct the API URL
    url = f"https://api.opencagedata.com/geocode/v1/json?q={encoded_address}&key={api_key}"
    
    # Make the API request
    response = requests.get(url)
    
    if response.status_code == 200:
        # Parse the JSON response
        data = response.json()
        
        # Check if there are any results
        if data['results']:
            # Extract the latitude and longitude from the first result
            latitude = data['results'][0]['geometry']['lat']
            longitude = data['results'][0]['geometry']['lng']
            return [latitude, longitude]
        else:
            raise ValueError("No results found for the given address.")
    else:
        raise Exception(f"API request failed with status code {response.status_code}")

def haversine(lat1, lon1, lat2, lon2):
    R = 6371  # Earth radius in kilometers. Use 3956 for miles.
    dlat = math.radians(lat2 - lat1)
    dlon = math.radians(lon2 - lon1)
    a = math.sin(dlat / 2) ** 2 + math.cos(math.radians(lat1)) * math.cos(math.radians(lat2)) * math.sin(dlon / 2) ** 2
    c = 2 * math.atan2(math.sqrt(a), math.sqrt(1 - a))
    distance = R * c
    return distance

def validate_zipcode(zipcode):
    try:
        if len(zipcode) == 5 and zipcode.isdigit():
            return True
        else:
            return False
    except:
        return False

# Function to handle form submission
@st.experimental_dialog("Fill out the form")
def form_dialog():
    city = st.radio("City", ("San Fransisco", "Oakland", "Berkeley"))
    sex = st.radio("Sex", ("Male", "Female", "Other"))
    lgbtq = st.radio("Do you identify as LGBTQ+ (some shelters serve specifically this community", ("Yes", "No"))
    domestic_violence = st.radio("Are you experiencing domestic violence (some shelters serve these individuals specifically", ("Yes", "No"))
    
    zipcode = st.text_input("Zipcode (Optional)", value="")
    urgency = st.radio("How quickly do you need help?", ("Today", "In the next few days", "In a week or more"))
    duration = st.radio("How long do you need a place to stay?", ("Overnight", "A month of less", "A couple of months", "A year or more"))
    
    needs = st.text_area("Needs (Optional - tell us what you need and how we can help)", value="")

    if st.button("Submit"):
        if zipcode and not validate_zipcode(zipcode):
            st.error("Please enter a valid 5-digit zipcode.")
        else:
            data = {
                "City": city,
                "Sex": sex,
                "LGBTQ": lgbtq,
                "Domestic Violence": domestic_violence,
                
                "Zipcode": zipcode,
                "Urgency": urgency,
                "Duration": duration,
                "Needs": needs
            }

            with open('data.json', 'w') as f:
                json.dump(data, f)

            st.session_state.form_submitted = True
            st.session_state.data = data
            st.rerun()

# Initialize session state
if 'form_submitted' not in st.session_state:
    st.session_state.form_submitted = False

if 'shelter_index' not in st.session_state:
    st.session_state.shelter_index = 0

shelters_def = [
    {"title": "Shelter 1", "description": "This is the 1st shelter",},
    {"title": "Shelter 2", "description": "This is the 2nd shelter.",},
    {"title": "Shelter 3", "description": "This is the 3rd shelter.",}
]

# Page config
st.set_page_config(
    page_title="ShelterSearch",
    layout="wide",
)

st.title("ShelterSearch")

if not st.session_state.form_submitted:
    if st.button("Open Form"):
        form_dialog()
else:
    with open('data.json', 'r') as f:
        data = json.load(f)

    # Display
    st.json(data)

    shelters = pd.read_csv("database.csv")
    # filter sex
    shelters = shelters[(shelters['Sex'] == data['Sex']) | (shelters['Sex'] == 'All')]
    # filter city
    shelters = shelters[(shelters['City'] == data['City'])]
    # filter lgbtq
    if data['LGBTQ'] == 'No':
        shelters = shelters[(shelters['LGBTQ'] == "No")]
    # filter domestic violence
    if data['Domestic Violence'] == 'No':
        shelters = shelters[(shelters['Domestic Violence'] == "No")]

    # calculate distances between zipcodes
    api_key = os.environ['OpenCage_API_KEY']
    
    shelters_coordinates = shelters.apply(lambda row: get_coordinates(row['Zip Code'], api_key), axis=1).tolist()
    user_coordinates = get_coordinates(data['Zip Code'])

    distances = []
    for coordinates in shelters_coordinates:
        distances.append(haversine(coordinates[0], coordinates[1], user_coordinates[0], user_coordinates[1]))

    shelters['zipcode_score'] = distances

    # urgency

    # duration

    # services
        
    st.table(shelters)

    # Display the current shelter information
    shelter = shelters_def[st.session_state.shelter_index]
    st.write(shelter["description"])
    
    # Create two columns
    col1, col2 = st.columns([1,1])
    
    # Add buttons to each column
    with col1:
        if st.button("Previous"):
            if st.session_state.shelter_index > 0:
                st.session_state.shelter_index -= 1
                st.experimental_rerun()
    
    with col2:
        if st.button("Next"):
            if st.session_state.shelter_index < len(shelters_def) - 1:
                st.session_state.shelter_index += 1
                st.experimental_rerun()