#pragma once
#include <iostream>
#include <map>
#include <vector>
#include <stdexcept>
#include <limits>

namespace ByteTrackEigen {
    // Enum class for defining the state of a track.
    enum class TrackState {
        New,      // Indicates a newly created track.
        Tracked,  // Indicates a track that is currently being tracked.
        Lost,     // Indicates a track that has been lost.
        Removed   // Indicates a track that has been removed.
    };

    /**
     * @brief The BaseTrack class serves as the foundational class for object tracking.
     *        It defines the essential attributes and methods for a track, such as ID, state, score, features, and history.
     *        The class provides mechanisms to handle the state of a track, including creating, updating, and maintaining its lifecycle.
     *        Designed to be extended, it allows for specific tracking functionalities to be implemented in derived classes.
     */
    class BaseTrack {
    private:
        static int _count; // Static counter used to assign unique IDs to each track.

    protected:
        int track_id; // Unique identifier for the track.
        bool is_activated; // Flag to indicate if the track is active.
        TrackState state; // Current state of the track.
        std::map<int, int> history; // History of track updates, typically storing frame ID and associated data.
        std::vector<int> features; // Features associated with the track.
        int curr_feature; // Current feature of the track.
        float score; // Score associated with the track, indicating the confidence of tracking.
        int start_frame; // Frame at which the track was started.
        int frame_id; // Current frame ID of the track.
        int time_since_update; // Time elapsed since the last update.
        std::pair<double, double> location; // Current location of the track.

    public:
        // Default constructor.
        BaseTrack();

        // Constructor with score initialization.
        BaseTrack(float score);

        // Returns the end frame of the track.
        int end_frame() const;

        // Generates the next unique track ID.
        static int next_id();

        // Activates the track. This method is intended to be overridden in derived classes.
        virtual void activate();

        // Predicts the next state of the track. This method is intended to be overridden in derived classes.
        virtual void predict();

        // Updates the track with new data. This method is intended to be overridden in derived classes.
        virtual void update();

        // Marks the track as lost.
        void mark_lost();

        // Marks the track as removed.
        void mark_removed();

        // Resets the static track ID counter. Useful for unit testing or reinitializing the tracking system.
        static void reset_count();

        // Getter for is_activated.
        bool get_is_activated() const;

        // Getter for state.
        TrackState get_state() const;

        // Getter for score.
        float get_score() const;

        // Getter for start_frame.
        int get_start_frame() const;

        // Getter for frame_id.
        int get_frame_id() const;

        // Getter for track_id.
        int get_track_id() const;
    };

}