#include "haader.h"

#include <time.h>
#include <math.h>

#include <iostream>
#include <sstream>
#include <fstream>
#include <iomanip>

using namespace std;


void print_usage(const char *argv_0) {
    cout << "Construct an HDR-image from a series of photographs\n";
    cout << "with different exposure times and then synthesize\n";
    cout << "new images from it.\n\n";
    cout << "Usage:\n";
    cout << argv_0 << " <image_path_1> <image_path_2> ...\n\n";
}

int main(int argc, char *argv[])
{
    if (argc >= 2) {
        haader::HdrImageStack stack;

        // read image files.
        bool ok = stack.read_from_files(argv + 1, argc - 1);

        if (ok) {
            clock_t start = clock();

            // construct and save average image
            {
                haader::Image img;
                stack.get_average_image(img);
                img.save_as_ppm_file("average.ppm");
            }

            // approximate inverse response function
            haader::InverseResponseFunction irf;
            bool irf_ok = stack.get_inverse_response_function(irf, 1000);

            {
                fstream s;
                s.open("irf.csv", std::ios::out);
                irf.to_csv_stream(s);
            }

            if (irf_ok) {
                haader::HdrImage hdr_img;
                hdr_img = stack.get_hdr_image(irf);

                // save logarithmic image of scene luminance values
                {
                    haader::Image x = hdr_img.get_log_image();
                    x.save_as_ppm_file("log_image.ppm");
                }

                // convert irf to response function
                haader::ResponseFunction rf;
                rf = irf.to_response_function(1024);

                {
                    fstream s;
                    s.open("rf.csv", std::ios::out);
                    rf.to_csv_stream(s);
                }

                {
                    haader::Image x = hdr_img.expose(0.001, rf, 1.0);
                    x.save_as_ppm_file("test_1000.ppm");
                }

                {
                    haader::Image x = hdr_img.expose(1.0 / 1024.0, rf, 1.0);
                    x.save_as_ppm_file("test_1024.ppm");
                }

                // create images by a simulated exposure of the HDR image with the response function
                cout << "Expose..." << endl;
                for (int i = 0; i < 20; i++) {
                    // exposure time
                    double t = pow(2.0, (double)i * (-12.0 / 20.0));

                    // create image
                    haader::Image x = hdr_img.expose(t, rf, 1.0);

                    // save image
                    stringstream ss;
                    ss << "expose_" << setw(5) << setfill('0') << i << ".ppm";
                    string path = ss.str();
                    x.save_as_ppm_file(path.c_str());

                    cout << "\nexposure time: " << t << " sec" << endl;
                    cout << "save as " << path << endl;
                }
            }

            clock_t end = clock();
            double seconds = (end - start) / (double)CLOCKS_PER_SEC;
            cout << "\nsecs: " << seconds << endl;
        }
    } else {
        print_usage(argv[0]);
    }

    return 0;
}