// Copyright (C) 2012  Davis E. King (davis@dlib.net)
// License: Boost Software License   See LICENSE.txt for the full license.
#ifndef DLIB_LOAD_IMAGE_DaTASET_H__
#define DLIB_LOAD_IMAGE_DaTASET_H__

#include "load_image_dataset_abstract.h"
#include "../misc_api.h"
#include "../dir_nav.h"
#include "../image_io.h"
#include "../array.h"
#include <vector>
#include "../geometry.h"
#include "image_dataset_metadata.h"
#include <string>
#include "../image_processing/full_object_detection.h"


namespace dlib
{

// ----------------------------------------------------------------------------------------

    template <
        typename image_type, 
        typename MM
        >
    void load_image_dataset (
        array<image_type,MM>& images,
        std::vector<std::vector<rectangle> >& object_locations,
        const std::string& filename,
        const std::string& label,
        bool skip_empty_images = false
    )
    {
        images.clear();
        object_locations.clear();
        const std::string old_working_dir = get_current_dir();

        // Set the current directory to be the one that contains the
        // metadata file. We do this because the file might contain
        // file paths which are relative to this folder.
        const std::string parent_dir = get_parent_directory(file(filename)).full_name();
        set_current_dir(parent_dir);


        using namespace dlib::image_dataset_metadata;

        dataset data;
        load_image_dataset_metadata(data, filename);

        image_type img;
        std::vector<rectangle> rects;
        for (unsigned long i = 0; i < data.images.size(); ++i)
        {
            rects.clear();
            for (unsigned long j = 0; j < data.images[i].boxes.size(); ++j)
            {
                if (label.size() == 0 || data.images[i].boxes[j].label == label)
                {
                    rects.push_back(data.images[i].boxes[j].rect);
                }
            }

            if (!skip_empty_images || rects.size() != 0)
            {
                object_locations.push_back(rects);
                load_image(img, data.images[i].filename);
                images.push_back(img);
            }
        }

        set_current_dir(old_working_dir);
    }

// ----------------------------------------------------------------------------------------

    template <
        typename image_type, 
        typename MM
        >
    void load_image_dataset (
        array<image_type,MM>& images,
        std::vector<std::vector<rectangle> >& object_locations,
        const std::string& filename
    )
    {
        load_image_dataset(images, object_locations, filename, "");
    }

// ----------------------------------------------------------------------------------------

    template <
        typename image_type, 
        typename MM
        >
    std::vector<std::string> load_image_dataset (
        array<image_type,MM>& images,
        std::vector<std::vector<full_object_detection> >& object_locations,
        const std::string& filename,
        const std::string& label,
        bool skip_empty_images = false
    )
    {
        images.clear();
        object_locations.clear();
        const std::string old_working_dir = get_current_dir();

        // Set the current directory to be the one that contains the
        // metadata file. We do this because the file might contain
        // file paths which are relative to this folder.
        const std::string parent_dir = get_parent_directory(file(filename)).full_name();
        set_current_dir(parent_dir);


        using namespace dlib::image_dataset_metadata;

        dataset data;
        load_image_dataset_metadata(data, filename);
        std::set<std::string> all_parts;

        // find out what parts are being used in the dataset.  Store results in all_parts.
        for (unsigned long i = 0; i < data.images.size(); ++i)
        {
            for (unsigned long j = 0; j < data.images[i].boxes.size(); ++j)
            {
                if (label.size() == 0 || data.images[i].boxes[j].label == label)
                {
                    const std::map<std::string,point>& parts = data.images[i].boxes[j].parts;
                    std::map<std::string,point>::const_iterator itr;

                    for (itr = parts.begin(); itr != parts.end(); ++itr)
                    {
                        all_parts.insert(itr->first);
                    }
                }
            }
        }

        // make a mapping between part names and the integers [0, all_parts.size())
        std::map<std::string,int> parts_idx;
        std::vector<std::string> ret_parts_list;
        for (std::set<std::string>::iterator i = all_parts.begin(); i != all_parts.end(); ++i)
        {
            parts_idx[*i] = ret_parts_list.size();
            ret_parts_list.push_back(*i);
        }

        image_type img;
        std::vector<full_object_detection> object_dets;
        for (unsigned long i = 0; i < data.images.size(); ++i)
        {
            object_dets.clear();
            for (unsigned long j = 0; j < data.images[i].boxes.size(); ++j)
            {
                if (label.size() == 0 || data.images[i].boxes[j].label == label)
                {
                    std::vector<point> partlist(parts_idx.size(), OBJECT_PART_NOT_PRESENT);

                    // populate partlist with all the parts present in this box.
                    const std::map<std::string,point>& parts = data.images[i].boxes[j].parts;
                    std::map<std::string,point>::const_iterator itr;
                    for (itr = parts.begin(); itr != parts.end(); ++itr)
                    {
                        partlist[parts_idx[itr->first]] = itr->second;
                    }

                    object_dets.push_back(full_object_detection(data.images[i].boxes[j].rect, partlist));
                }
            }

            if (!skip_empty_images || object_dets.size() != 0)
            {
                object_locations.push_back(object_dets);
                load_image(img, data.images[i].filename);
                images.push_back(img);
            }
        }

        set_current_dir(old_working_dir);

        return ret_parts_list;
    }

// ----------------------------------------------------------------------------------------

    template <
        typename image_type, 
        typename MM
        >
    std::vector<std::string> load_image_dataset (
        array<image_type,MM>& images,
        std::vector<std::vector<full_object_detection> >& object_locations,
        const std::string& filename
    )
    {
        return load_image_dataset(images, object_locations, filename, "");
    }

// ----------------------------------------------------------------------------------------

}

#endif // DLIB_LOAD_IMAGE_DaTASET_H__