#pragma once

#include <opencv2/core.hpp>
#include <opencv2/imgproc.hpp>
#include "../vp_node.h"

namespace vp_nodes {
    // on screen display(short as osd) node.
    // another version for vp_frame_face_target display, including displaying similarity between faces.
    class vp_face_osd_node_v2: public vp_node
    {
    private:
        // leave a gap at the bottom of osd frame
        int gap_height = 112;
        int padding = 5;

        // cache for display
        cv::Mat the_baseline_face;                       // the first face detected in frames
        std::vector<float> the_baseline_face_feature;    // the feature of first face in frames
        std::vector<cv::Mat> faces_list;                 // faces detected except the first one
        std::vector<std::vector<float>> face_features;   // face features except the first one
        std::vector<float> cosine_distances;             // cosine distance between face and the first one
        std::vector<float> l2_distances;                 // l2 distance between face and the first one

        double cosine_similar_thresh = 0.363;  // higher value means higher similarity, max 1.0
        double l2norm_similar_thresh = 1.128;  // lower value means higher similarity, min 0.0

        // calculate distance
        // 0 cosine distance 
        // 1 l2 distance
        double match(std::vector<float>& feature1, std::vector<float>& feature2, int dis_type);
        
    protected:
        virtual std::shared_ptr<vp_objects::vp_meta> handle_frame_meta(std::shared_ptr<vp_objects::vp_frame_meta> meta) override;
    public:
        vp_face_osd_node_v2(std::string node_name);
        ~vp_face_osd_node_v2();
    };
}