app.py

import torch
import torch.nn as nn
import gradio as gr
import pandas as pd
import numpy as np
from sklearn.metrics import mean_absolute_error, mean_squared_error
import os
import logging
import joblib
from tqdm import tqdm
import tempfile
import json
from math import radians, cos, sin, asin, sqrt, atan2, degrees
import time
import functools

# ============================
# Configure Logging
# ============================

logging.basicConfig(level=logging.INFO, format='%(asctime)s - %(levelname)s - %(message)s')



def add_time_decimal_feature(df):
    """
    Add 'time_decimal' feature by combining 'hour' and 'minutes'.
    :param df: DataFrame with 'hour' and 'minutes' columns.
    :return: DataFrame with 'time_decimal' and without 'hour' and 'minutes'.
    """
    if 'time_decimal' in df.columns:
        logging.info("'time_decimal' feature already exists. Skipping creation.")
        return df
    elif 'hour' in df.columns and 'minutes' in df.columns:
        logging.info("Adding 'time_decimal' feature...")
        df['time_decimal'] = df['hour'] + df['minutes'] / 60.0
        df = df.drop(columns=['hour', 'minutes'])  # Drop 'hour' and 'minutes' after creation
        logging.info("'time_decimal' feature added.")
    else:
        logging.warning("Neither 'time_decimal' nor 'hour' and 'minutes' columns found. Cannot create 'time_decimal' feature.")
        raise ValueError("Input data must contain 'time_decimal' or both 'hour' and 'minutes' columns.")
    return df

def haversine(lon1, lat1, lon2, lat2):
    """
    Calculate the great-circle distance between two points on the Earth.
    :param lon1: Longitude of point 1 (in decimal degrees)
    :param lat1: Latitude of point 1 (in decimal degrees)
    :param lon2: Longitude of point 2 (in decimal degrees)
    :param lat2: Latitude of point 2 (in decimal degrees)
    :return: Distance in kilometers
    """
    # Convert decimal degrees to radians
    lon1_rad, lat1_rad, lon2_rad, lat2_rad = map(np.radians, [lon1, lat1, lon2, lat2])

    # Haversine formula
    dlon = lon2_rad - lon1_rad 
    dlat = lat2_rad - lat1_rad 
    a = np.sin(dlat/2)**2 + np.cos(lat1_rad) * np.cos(lat2_rad) * np.sin(dlon/2)**2
    c = 2 * np.arcsin(np.sqrt(a)) 
    r = 6371  # Radius of Earth in kilometers
    return c * r

def calculate_bearing(lon1, lat1, lon2, lat2):
    """
    Calculate the bearing between two points.
    :param lon1: Longitude of point 1 (in decimal degrees)
    :param lat1: Latitude of point 1 (in decimal degrees)
    :param lon2: Longitude of point 2 (in decimal degrees)
    :param lat2: Latitude of point 2 (in decimal degrees)
    :return: Bearing in degrees
    """
    # Convert decimal degrees to radians
    lon1_rad, lat1_rad, lon2_rad, lat2_rad = map(radians, [lon1, lat1, lon2, lat2])

    dlon = lon2_rad - lon1_rad
    x = sin(dlon) * cos(lat2_rad)
    y = cos(lat1_rad) * sin(lat2_rad) - (sin(lat1_rad) * cos(lat2_rad) * cos(dlon))

    initial_bearing = atan2(x, y)

    # Convert from radians to degrees and normalize
    initial_bearing = degrees(initial_bearing)
    compass_bearing = (initial_bearing + 360) % 360

    return compass_bearing

def angular_divergence(bearing1, bearing2):
    """
    Calculate the smallest angle difference between two bearings.
    :param bearing1: First bearing in degrees
    :param bearing2: Second bearing in degrees
    :return: Angular divergence in degrees
    """
    diff = abs(bearing1 - bearing2) % 360
    return min(diff, 360 - diff)

def denormalize(scaled_lat, scaled_lon, scaler, lat_idx, lon_idx):
    """
    Denormalize latitude and longitude using the scaler's parameters.
    :param scaled_lat: Scaled latitude values (numpy array).
    :param scaled_lon: Scaled longitude values (numpy array).
    :param scaler: The scaler object used for normalization.
    :param lat_idx: Index of 'latitude_degrees' in the scaler's feature list.
    :param lon_idx: Index of 'longitude_degrees' in the scaler's feature list.
    :return: Tuple of (denormalized_lat, denormalized_lon).
    """
    lat_min = scaler.data_min_[lat_idx]
    lat_max = scaler.data_max_[lat_idx]
    lon_min = scaler.data_min_[lon_idx]
    lon_max = scaler.data_max_[lon_idx]

    denorm_lat = scaled_lat * (lat_max - lat_min) + lat_min
    denorm_lon = scaled_lon * (lon_max - lon_min) + lon_min
    return denorm_lat, denorm_lon

def create_dataset_grouped_by_mmsi(df_scaled, seq_len, forecast_horizon, features_to_scale, future_features):
    """
    Create input and output sequences grouped by original MMSI.
    Returns scaled last known positions.
    """
    Xs, ys, mmsis = [], [], []
    last_known_positions_scaled = []

    grouped = df_scaled.groupby('original_mmsi')

    for mmsi, group in tqdm(grouped, desc="Creating sequences"):
        if len(group) >= seq_len + forecast_horizon:
            for i in range(len(group) - seq_len - forecast_horizon + 1):
                # Select scaled features for the sequence
                sequence = group.iloc[i:(i + seq_len)][features_to_scale].to_numpy()

                # Future positions to predict (scaled)
                future_positions = group[['latitude_degrees', 'longitude_degrees']].iloc[i + seq_len:i + seq_len + forecast_horizon].to_numpy()

                # Future features
                future_feature_values = group[future_features].iloc[i + seq_len].values
                future_feature_array = np.tile(future_feature_values, (seq_len, 1))

                # Combine sequence with future features
                sequence_with_future_features = np.hstack((sequence, future_feature_array))

                Xs.append(sequence_with_future_features)
                ys.append(future_positions)
                mmsis.append(mmsi)

                # Store last known positions (scaled)
                last_lat_scaled = group['latitude_degrees'].iloc[i + seq_len - 1]
                last_lon_scaled = group['longitude_degrees'].iloc[i + seq_len - 1]
                last_known_positions_scaled.append((last_lat_scaled, last_lon_scaled))

    return np.array(Xs, dtype=np.float32), np.array(ys, dtype=np.float32), np.array(mmsis), last_known_positions_scaled

# ============================
# Model Definitions
# ============================

class LSTMModelTeacher(nn.Module):
    def __init__(self, in_dim, hidden_dim, forecast_horizon, n_layers=7, dropout=0.2):
        """
        Teacher LSTM Model.
        :param in_dim: Number of input features.
        :param hidden_dim: Number of hidden units.
        :param forecast_horizon: Number of future steps to predict.
        :param n_layers: Number of LSTM layers.
        :param dropout: Dropout rate.
        """
        super(LSTMModelTeacher, self).__init__()
        self.forecast_horizon = forecast_horizon  # Store as an instance attribute
        self.embedding = nn.Linear(in_dim, hidden_dim)
        self.lstm = nn.LSTM(hidden_dim, hidden_dim, num_layers=n_layers, dropout=dropout, batch_first=True)
        self.fc = nn.Linear(hidden_dim, forecast_horizon * 2)

    def forward(self, x):
        x = self.embedding(x)
        x, _ = self.lstm(x)
        x = self.fc(x[:, -1, :])  # Use the last timestep for prediction
        x = x.view(-1, self.forecast_horizon, 2)  # Shape: (batch_size, forecast_horizon, 2)
        return x

class LSTMModelStudent(nn.Module):
    def __init__(self, in_dim, hidden_dim, forecast_horizon, n_layers=3, dropout=0.2):
        """
        Student LSTM Model.
        :param in_dim: Number of input features.
        :param hidden_dim: Number of hidden units.
        :param forecast_horizon: Number of future steps to predict.
        :param n_layers: Number of LSTM layers.
        :param dropout: Dropout rate.
        """
        super(LSTMModelStudent, self).__init__()
        self.forecast_horizon = forecast_horizon  # Store as an instance attribute
        self.embedding = nn.Linear(in_dim, hidden_dim)
        self.lstm = nn.LSTM(hidden_dim, hidden_dim, num_layers=n_layers, dropout=dropout, batch_first=True)
        self.fc = nn.Linear(hidden_dim, forecast_horizon * 2)

    def forward(self, x):
        x = self.embedding(x)
        x, _ = self.lstm(x)
        x = self.fc(x[:, -1, :])  # Use the last timestep for prediction
        x = x.view(-1, self.forecast_horizon, 2)  # Shape: (batch_size, forecast_horizon, 2)
        return x

# ============================
# Model Loading Functions
# ============================

def load_models(model_paths):
    """
    Load teacher, student, and cargo vessel models, including submodels for North, Mid, and South areas.
    :param model_paths: Dictionary containing paths to the models.
    :return: Dictionary of loaded models.
    """
    models = {}
    logging.info("Loading Teacher model...")
    # Teacher model input dimension
    teacher_in_dim = 15  # Features including 'future_hour_feature' (time_decimal)
    # Load Teacher Model (Global)
    teacher = LSTMModelTeacher(in_dim=teacher_in_dim, hidden_dim=200, forecast_horizon=1, n_layers=7, dropout=0.2)
    teacher.load_state_dict(torch.load(model_paths['teacher'], map_location=torch.device('cpu')))
    teacher.eval()
    models['Teacher'] = teacher
    logging.info("Teacher model loaded successfully.")

    logging.info("Loading Student North model...")
    # Student North model input dimension is the same as teacher
    student_north = LSTMModelStudent(in_dim=teacher_in_dim, hidden_dim=200, forecast_horizon=1, n_layers=3, dropout=0.2)
    student_north.load_state_dict(torch.load(model_paths['student_north'], map_location=torch.device('cpu')))
    student_north.eval()
    models['Student_North'] = student_north
    logging.info("Student North model loaded successfully.")

    logging.info("Loading Student Mid model...")
    student_mid = LSTMModelStudent(in_dim=teacher_in_dim, hidden_dim=200, forecast_horizon=1, n_layers=3, dropout=0.2)
    student_mid.load_state_dict(torch.load(model_paths['student_mid'], map_location=torch.device('cpu')))
    student_mid.eval()
    models['Student_Mid'] = student_mid
    logging.info("Student Mid model loaded successfully.")

    logging.info("Loading Student South model...")
    student_south = LSTMModelStudent(in_dim=teacher_in_dim, hidden_dim=200, forecast_horizon=1, n_layers=3, dropout=0.2)
    student_south.load_state_dict(torch.load(model_paths['student_south'], map_location=torch.device('cpu')))
    student_south.eval()
    models['Student_South'] = student_south
    logging.info("Student South model loaded successfully.")

    # Load Cargo Vessel model
    logging.info("Loading Cargo Vessel model...")
    # Cargo Vessel model input dimension
    cargo_in_dim = 6 + 3  # + 3 future features ('day', 'month', 'time_decimal')
    cargo_model = LSTMModelTeacher(in_dim=cargo_in_dim, hidden_dim=200, forecast_horizon=1, n_layers=10, dropout=0.2)
    cargo_model.load_state_dict(torch.load(model_paths['cargo_vessel'], map_location=torch.device('cpu')))
    cargo_model.eval()
    models['Cargo_Vessel'] = cargo_model
    logging.info("Cargo Vessel model loaded successfully.")

    return models

def load_scalers(scaler_paths):
    """
    Load scalers for each model.
    :param scaler_paths: Dictionary containing paths to the scaler files.
    :return: Dictionary of loaded scalers.
    """
    loaded_scalers = {}
    for model_name, scaler_path in scaler_paths.items():
        if os.path.exists(scaler_path):
            loaded_scalers[model_name] = joblib.load(scaler_path)
            logging.info(f"Loaded scaler for {model_name} from '{scaler_path}'.")
        else:
            logging.error(f"Scaler file for {model_name} not found at '{scaler_path}'.")
            raise FileNotFoundError(f"Scaler file for {model_name} not found at '{scaler_path}'. Please provide the correct path.")
    return loaded_scalers


def determine_subarea(df):
    """
    Determine the sub-area (North, Mid, South) based on latitude and longitude ranges.
    :param df: DataFrame containing 'latitude_degrees' and 'longitude_degrees'.
    :return: String indicating the sub-area.
    """
    # Define sub-area boundaries
    subareas = {
        'North': {'lat_min': 30, 'lat_max': 60, 'lon_min': -80, 'lon_max': -10},
        'Mid': {'lat_min': 0, 'lat_max': 30, 'lon_min': -80, 'lon_max': 10},
        'South': {'lat_min': -80, 'lat_max': 0, 'lon_min': -60, 'lon_max': 20}
    }

    # Count the number of data points in each sub-area
    counts = {}
    for area, bounds in subareas.items():
        count = df[
            (df['latitude_degrees'] >= bounds['lat_min']) & (df['latitude_degrees'] <= bounds['lat_max']) &
            (df['longitude_degrees'] >= bounds['lon_min']) & (df['longitude_degrees'] <= bounds['lon_max'])
        ].shape[0]
        counts[area] = count
        logging.info(f"Sub-area '{area}': {count} records.")

    # Determine the sub-area with the maximum count
    predominant_subarea = max(counts, key=counts.get)
    logging.info(f"Predominant sub-area determined: {predominant_subarea}")

    # If no data points fall into any sub-area, default to Teacher
    if counts[predominant_subarea] == 0:
        logging.warning("No data points found in any sub-area. Defaulting to Teacher model.")
        return 'Teacher'

    return predominant_subarea

def select_model(models, subarea, model_choice):
    """
    Select the appropriate model based on the sub-area and model choice.
    :param models: Dictionary of loaded models.
    :param subarea: String indicating the sub-area.
    :param model_choice: String indicating the selected model.
    :return: Tuple of (selected_model, selected_model_name).
    """
    if model_choice == "Auto-Select":
        if subarea in ['North', 'Mid', 'South']:
            selected_model = models.get(f'Student_{subarea}')
            selected_model_name = f'Student_{subarea}'
        else:
            selected_model = models.get('Teacher')
            selected_model_name = 'Teacher'
    else:
        selected_model = models.get(model_choice)
        selected_model_name = model_choice

    logging.info(f"Selected model: {selected_model_name}")
    return selected_model, selected_model_name

# ============================
# Evaluation Metrics Calculation
# ============================

def calculate_classic_metrics(y_true, y_pred):
    """
    Calculate MAE, MSE, and RMSE directly on latitude/longitude pairs.
    :param y_true: Ground truth positions (numpy array of shape (num_samples, 2)).
    :param y_pred: Predicted positions (numpy array of shape (num_samples, 2)).
    :return: Dictionary containing the classic metrics.
    """
    # Calculate MAE
    mae = mean_absolute_error(y_true, y_pred)

    # Calculate MSE
    mse = mean_squared_error(y_true, y_pred)

    # Calculate RMSE
    rmse = np.sqrt(mse)

    classic_metrics = {
        'MAE (degrees)': mae,
        'MSE (degrees^2)': mse,
        'RMSE (degrees)': rmse
    }

    logging.info(f"Calculated classic metrics: {classic_metrics}")
    
    return classic_metrics

def calculate_distance_metrics(y_true, y_pred):
    """
    Calculate metrics based on distance (in kilometers).
    :param y_true: Ground truth positions (numpy array of shape (num_samples, 2)).
    :param y_pred: Predicted positions (numpy array of shape (num_samples, 2)).
    :return: Dictionary containing the distance-based metrics.
    """
    # Calculate haversine distance between predicted and true positions
    distances = np.array([
        haversine(y_true[i, 1], y_true[i, 0], y_pred[i, 1], y_pred[i, 0]) 
        for i in range(len(y_true))
    ])  # Assuming columns are [latitude, longitude]

    # Calculate MAE
    mae = np.mean(np.abs(distances))

    # Calculate MSE
    mse = np.mean(np.square(distances))

    # Calculate RMSE
    rmse = np.sqrt(mse)

    # Calculate RSE (Relative Squared Error)
    variance = np.var(distances)
    rse = mse / variance if variance != 0 else float('inf')

    metrics = {
        'MAE (km)': mae,
        'MSE (km^2)': mse,
        'RMSE (km)': rmse,
        'RSE': rse
    }

    logging.info(f"Calculated distance metrics: {metrics}")
    
    return metrics

# ============================
# Classical Metrics Prediction
# ============================

def classical_prediction(file_path, model_choice, min_mmsi, max_mmsi, models, loaded_scalers):
    """
    Preprocess the input CSV and make predictions using the selected model.
    Calculate classical evaluation metrics and include inference time.
    """
    try:
        logging.info("Starting classical prediction...")

        # Load the uploaded CSV file and filter based on MMSI
        logging.info("Loading uploaded CSV file...")
        df = pd.read_csv(file_path, delimiter=',')
        logging.info(f"Uploaded CSV file loaded with {df.shape[0]} records.")
        
        df = df[(df['mmsi'] >= min_mmsi) & (df['mmsi'] <= max_mmsi)]
        if df.empty:
            error_message = "No data available after applying MMSI filters."
            logging.error(error_message)
            return {"error": error_message}, None, None, None

        # Select the appropriate model and scaler
        if model_choice == "Auto-Select":
            temp_df = df.copy()
            subarea = determine_subarea(temp_df)
            selected_model, selected_model_name = select_model(models, subarea, model_choice)
            scaler = loaded_scalers[selected_model_name]
        else:
            if model_choice in models:
                selected_model = models[model_choice]
                selected_model_name = model_choice
                scaler = loaded_scalers[selected_model_name]
            else:
                error_message = f"Selected model '{model_choice}' is not available."
                logging.error(error_message)
                return {"error": error_message}, None, None, None

        logging.info(f"Using scaler for model: {selected_model_name}")

        # Adjust features_to_scale based on the selected model
        if selected_model_name == 'Cargo_Vessel':
            features_to_scale = [
                "mmsi", "latitude_degrees", "longitude_degrees",
                "day", "month", "time_decimal"  # Removed 'ship_type'
            ]
            future_features = ['day', 'month', 'time_decimal']
        else:
            features_to_scale = [
                "mmsi", "sog_kt", "latitude_degrees", "longitude_degrees", "cog_degrees",
                "dimension_a_m", "dimension_b_m", "dimension_c_m", "dimension_d_m",
                "ship_type", "day", "month", "year", "time_decimal"
            ]
            future_features = ['time_decimal']

        # Check if the necessary columns exist
        expected_columns = features_to_scale
        if not all(col in df.columns for col in expected_columns):
            error_message = (
                f"Input data does not have the correct columns.\n"
                f"Expected columns for {selected_model_name}: {expected_columns}\n"
                f"Got columns: {list(df.columns)}"
            )
            logging.error(error_message)
            return {"error": error_message}, None, None, None

        logging.info("Input CSV has the correct columns.")

        
        if selected_model_name != 'Cargo_Vessel':
            df = add_time_decimal_feature(df)
        else:
            if 'time_decimal' not in df.columns:
                error_message = "Cargo model requires 'time_decimal' column."
                logging.error(error_message)
                return {"error": error_message}, None, None, None

        # Normalize the data
        logging.info("Normalizing the data...")
        X_new = df[features_to_scale]
        X_scaled = scaler.transform(X_new)
        df_scaled = pd.DataFrame(X_scaled, columns=features_to_scale, index=df.index)
        df_scaled['original_mmsi'] = df['mmsi']

        # Create sequences and get last known positions (scaled)
        seq_len = 24
        forecast_horizon = 1
        X, y, mmsi_seq, last_known_positions_scaled = create_dataset_grouped_by_mmsi(
            df_scaled, seq_len, forecast_horizon, features_to_scale, future_features
        )

        if X.size == 0:
            error_message = "Not enough data to create sequences."
            logging.error(error_message)
            return {"error": error_message}, None, None, None

        logging.info(f"Created {X.shape[0]} sequences.")

        # Inference
        logging.info("Starting model inference...")
        test_dataset = torch.utils.data.TensorDataset(torch.tensor(X, dtype=torch.float32), torch.tensor(y, dtype=torch.float32))
        test_loader = torch.utils.data.DataLoader(test_dataset, batch_size=32, shuffle=False)
        all_predictions = []
        all_y_true = []

        start_time = time.time()  # Start inference time tracking

        with torch.no_grad():
            for batch in test_loader:
                X_batch, y_batch = batch
                predictions = selected_model(X_batch).cpu().numpy()
                all_predictions.append(predictions)
                all_y_true.append(y_batch.numpy())

        inference_time = time.time() - start_time  # End inference time 

        all_predictions = np.concatenate(all_predictions, axis=0)
        y_true = np.concatenate(all_y_true, axis=0)
        y_pred = all_predictions

        logging.info(f"Inference completed in {inference_time:.2f} seconds.")

        # Denormalize predictions and real values
        lat_idx = features_to_scale.index("latitude_degrees")
        lon_idx = features_to_scale.index("longitude_degrees")
        pred_lat, pred_lon = denormalize(y_pred[:, :, 0], y_pred[:, :, 1], scaler, lat_idx, lon_idx)
        true_lat, true_lon = denormalize(y_true[:, :, 0], y_true[:, :, 1], scaler, lat_idx, lon_idx)

        # Denormalize last known positions
        last_lat_scaled = np.array([pos[0] for pos in last_known_positions_scaled])
        last_lon_scaled = np.array([pos[1] for pos in last_known_positions_scaled])

        last_lat_denorm, last_lon_denorm = denormalize(
            last_lat_scaled, last_lon_scaled, scaler, lat_idx, lon_idx
        )

        # Squeeze arrays to ensure they are 1-dimensional
        pred_lat = pred_lat.squeeze()
        pred_lon = pred_lon.squeeze()
        true_lat = true_lat.squeeze()
        true_lon = true_lon.squeeze()
        last_lat_denorm = last_lat_denorm.squeeze()
        last_lon_denorm = last_lon_denorm.squeeze()
        mmsi_seq = mmsi_seq.squeeze()

        # Calculate the classic evaluation metrics
        y_true_pairs = np.column_stack((true_lat, true_lon))
        y_pred_pairs = np.column_stack((pred_lat, pred_lon))
        classic_metrics = calculate_classic_metrics(y_true=y_true_pairs, y_pred=y_pred_pairs)
        classic_metrics['Inference Time (seconds)'] = inference_time  # Include inference time

        # Calculate error in Km for each prediction
        logging.info("Calculating error in kilometers for each prediction...")
        error_km = np.array([
            haversine(pred_lon[i], pred_lat[i], true_lon[i], true_lat[i])
            for i in range(len(pred_lat))
        ])

        # Prepare metrics and output CSV
        metrics_df = pd.DataFrame([classic_metrics])
        metrics_json = metrics_df.to_json(orient="records")
        metrics_json = json.loads(metrics_json)[0]

        # Prepare predicted and real positions DataFrame, including error in Km
        predicted_df = pd.DataFrame({
            'MMSI': mmsi_seq[:len(y_pred)],
            'Last Known Latitude': last_lat_denorm,
            'Last Known Longitude': last_lon_denorm,
            'Predicted Latitude': pred_lat,
            'Predicted Longitude': pred_lon,
            'Real Latitude': true_lat,
            'Real Longitude': true_lon,
            'Error (Km)': error_km
        })

        # Save predictions as CSV
        with tempfile.NamedTemporaryFile(delete=False, suffix='.csv', mode='w', newline='') as tmp_positions_file:
            predicted_df.to_csv(tmp_positions_file, index=False)
            positions_csv_path = tmp_positions_file.name

        logging.info("Classical prediction completed.")
        return metrics_json, positions_csv_path, inference_time, None
    except Exception as e:
        logging.error(f"An error occurred: {str(e)}")
        return None, None, None, str(e)


# ============================
# Abnormal Behavior Detection
# ============================

def abnormal_behavior_detection(prediction_file_path, alpha=0.5, threshold=10.0):
    """
    Detect abnormal behavior based on angular divergence and distance difference.
    Accepts a CSV file containing real and predicted positions.
    """
    try:
        logging.info("Starting abnormal behavior detection...")

        # Load the CSV file containing real and predicted positions
        logging.info("Loading prediction CSV file...")
        df = pd.read_csv(prediction_file_path)
        logging.info(f"Prediction CSV file loaded with {df.shape[0]} records.")

        # Check if necessary columns exist
        expected_columns = [
            'MMSI',
            'Last Known Latitude',
            'Last Known Longitude',
            'Predicted Latitude',
            'Predicted Longitude',
            'Real Latitude',
            'Real Longitude'
        ]

        if not all(col in df.columns for col in expected_columns):
            error_message = (
                f"Input data does not have the correct columns.\n"
                f"Expected columns: {expected_columns}\n"
                f"Got columns: {list(df.columns)}"
            )
            logging.error(error_message)
            return None, error_message

        # Extract necessary data
        mmsi_seq = df['MMSI'].values
        last_lat_flat = df['Last Known Latitude'].values
        last_lon_flat = df['Last Known Longitude'].values
        pred_lat_flat = df['Predicted Latitude'].values
        pred_lon_flat = df['Predicted Longitude'].values
        true_lat_flat = df['Real Latitude'].values
        true_lon_flat = df['Real Longitude'].values

        # Calculate bearings
        logging.info("Calculating bearings for predictions and real values...")
        bearings_pred = [
            calculate_bearing(last_lon_flat[i], last_lat_flat[i], pred_lon_flat[i], pred_lat_flat[i]) 
            for i in range(len(pred_lat_flat))
        ]
        bearings_true = [
            calculate_bearing(last_lon_flat[i], last_lat_flat[i], true_lon_flat[i], true_lat_flat[i]) 
            for i in range(len(true_lat_flat))
        ]

        # Calculate angular divergence Δθ
        logging.info("Calculating angular divergence (Δθ)...")
        delta_theta = [
            angular_divergence(bearings_pred[i], bearings_true[i]) 
            for i in range(len(bearings_pred))
        ]

        # Calculate distance difference Δd
        logging.info("Calculating distance difference (Δd)...")
        delta_d = [
            haversine(last_lon_flat[i], last_lat_flat[i], pred_lon_flat[i], pred_lat_flat[i]) - 
            haversine(last_lon_flat[i], last_lat_flat[i], true_lon_flat[i], true_lat_flat[i])
            for i in range(len(pred_lat_flat))
        ]

        # Compute the score
        logging.info("Computing the abnormal behavior score...")
        score = [alpha * abs(dd) + (1 - alpha) * dt for dd, dt in zip(delta_d, delta_theta)]

        # Determine abnormal behavior
        logging.info("Determining abnormal behavior based on the score...")
        abnormal_behavior = [1 if s >= threshold else 0 for s in score]  # 1: Abnormal, 0: Normal

        # Create DataFrame for saving
        abnormal_behavior_df = pd.DataFrame({
            'MMSI': mmsi_seq,
            'Last Known Latitude': last_lat_flat,
            'Last Known Longitude': last_lon_flat,
            'Predicted Latitude': pred_lat_flat,
            'Predicted Longitude': pred_lon_flat,
            'Real Latitude': true_lat_flat,
            'Real Longitude': true_lon_flat,
            'Distance Difference (Δd) [km]': delta_d,
            'Angular Divergence (Δθ) [degrees]': delta_theta,
            'Score (αΔd + (1-α)Δθ)': score,
            'Abnormal Behavior (1=Abnormal, 0=Normal)': abnormal_behavior
        })

        # Save abnormal behavior dataset as CSV
        with tempfile.NamedTemporaryFile(delete=False, suffix='.csv', mode='w', newline='') as tmp_abnormal_file:
            abnormal_behavior_df.to_csv(tmp_abnormal_file, index=False)
            abnormal_csv_path = tmp_abnormal_file.name

        logging.info("Abnormal behavior detection completed.")
        return abnormal_csv_path, None
    except Exception as e:
        logging.error(f"An error occurred: {str(e)}")
        return None, str(e)

# ============================
# Define Gradio Interface
# ============================

def main():


    model_paths = {
         'teacher': 'LSTM_whole_atlantic_horizon1_with_time_decimal_input_batch256/horizon_data_LSTM_whole_atlantic_horizon1_with_time_decimal_input_batch256_seq_24/run_1/best_model.pth',
        'student_north': 'LSTM_whole_atlantic_horizon1_with_time_decimal_input_batch256_KD_North/horizon1_data_LSTM_whole_atlantic_horizon1_with_time_decimal_input_batch256_KD_North_seq_24/run_1/best_model.pth',
        'student_mid': 'LSTM_whole_atlantic_horizon1_with_time_decimal_input_batch256_KD_Mid/horizon1_data_LSTM_whole_atlantic_horizon1_with_time_decimal_input_batch256_KD_Mid_seq_24/run_1/best_model.pth',
        'student_south': 'LSTM_whole_atlantic_horizon1_with_time_decimal_input_batch256_KD_South/horizon1_data_LSTM_whole_atlantic_horizon1_with_time_decimal_input_batch256_KD_South_seq_24/run_1/best_model.pth',
        'cargo_vessel': 'LSTMModel_cargo_horizon1_with_month_day_time_input_batch256_cleaned/horizon_data_LSTMModel_cargo_horizon1_with_month_day_time_input_batch256_cleaned_seq_24/run_1/best_model.pth' 
    }

    scaler_paths = {
        'Teacher': 'scaler_train_wholedata_up.joblib',
        'Student_North': 'scaler_train_North_up.joblib',
        'Student_Mid': 'scaler_train_Mid_up.joblib',
        'Student_South': 'scaler_train_South_up.joblib',
        'Cargo_Vessel': 'scaler_features_cargo_cleaned.joblib' 
    }


    logging.info("Loading models and scalers...")
    models = load_models(model_paths)
    loaded_scalers = load_scalers(scaler_paths)
    logging.info("All models and scalers loaded successfully.")

    # Define the Gradio components for classical prediction tab
    classical_tab = gr.Interface(
        fn=functools.partial(classical_prediction, models=models, loaded_scalers=loaded_scalers),
        inputs=[
            gr.File(label="Upload CSV File", type='filepath'),
            gr.Dropdown(
                choices=["Auto-Select", "Teacher", "Student_North", "Student_Mid", "Student_South", "Cargo_Vessel"],
                value="Auto-Select",
                label="Choose Model"
            ),
            gr.Number(label="Min MMSI", value=0),
            gr.Number(label="Max MMSI", value=999999999)
        ],
        outputs=[
            gr.JSON(label="Classical Metrics (Degrees)"),
            gr.File(label="Download Predicted & Real Positions CSV"),
            gr.Number(label="Inference Time (seconds)"),
            gr.Textbox(label="Error Message", lines=2, visible=False)
        ],
        title="Classical Prediction & Metrics",
        description=(
            "Upload a CSV file and select a model to get classical evaluation metrics such as MAE, MSE, RMSE. "
            "The inference time is also provided."
        )
    )

    # Define the Gradio components for abnormal behavior detection tab
    abnormal_tab = gr.Interface(
        fn=functools.partial(abnormal_behavior_detection),
        inputs=[
            gr.File(label="Upload Predicted Positions CSV", type='filepath'),
            gr.Slider(minimum=0, maximum=1, step=0.1, value=0.5, label="Alpha (α)"),
            gr.Number(label="Threshold", value=10.0)
        ],
        outputs=[
            gr.File(label="Download Abnormal Behavior CSV"),
            gr.Textbox(label="Error Message", lines=2, visible=False)
        ],
        title="Abnormal Behavior Detection",
        description=(
            "Upload the CSV file containing real and predicted positions from the Classical Prediction tab. "
            "Adjust the Alpha and Threshold parameters to compute abnormal behavior."
        )
    )


    # Combine the two tabs using Gradio Tabs component
    with gr.Blocks() as demo:
        gr.Markdown("# Vessel Trajectory Prediction and Abnormal Behavior Detection")
        with gr.Tabs():
            with gr.TabItem("Classical Prediction"):
                classical_tab.render()
            with gr.TabItem("Abnormal Behavior Detection"):
                abnormal_tab.render()

    # Launch the Gradio interface
    logging.info("Launching Gradio interface...")
    demo.launch()
    logging.info("Gradio interface launched successfully.")

# Run the app
if __name__ == "__main__":
    main()