#include "svg.h"

using namespace std;

void
svg_begin(double width, double height) {
    cout << "<?xml version='1.0' encoding='UTF-8'?>\n";
    cout << "<svg ";
    cout << "width='" << width << "' ";
    cout << "height='" << height << "' ";
    cout << "viewBox='0 0 " << width << " " << height << "' ";
    cout << "xmlns='http://www.w3.org/2000/svg'>\n";
}

void
svg_end() {
    cout << "</svg>\n";
}

void
svg_text(double left, double baseline, string text) {
    cout << "<text x='" << left << "' y='" << baseline << "'>" << text << "</text>";
}
void
svg_rect(double x, double y, double width, double height, string stroke, string fill){
    cout << "<rect x='" << x << "' y='" << y <<"' width='" << width << "' height='" << height << "' stroke='" << stroke << "' fill='" << fill << "'/>";
}
void
show_histogram_svg(const vector<size_t>& bins) {
    const auto IMAGE_WIDTH = 400;
    const auto IMAGE_HEIGHT = 300;
    const auto TEXT_LEFT = 20;
    const auto TEXT_BASELINE = 20;
    const auto TEXT_WIDTH = 50;
    const auto BIN_HEIGHT = 30;
    const auto BLOCK_WIDTH = 10;

    svg_begin(400, 300);
    double top = 0;

    size_t maxbin = 0;
    for (size_t bin : bins){
        if (bin > maxbin){
            maxbin = bin;
        }
    }
    if (maxbin * BLOCK_WIDTH <= IMAGE_WIDTH - TEXT_WIDTH){
        for (size_t bin : bins) {
            const double bin_width = BLOCK_WIDTH * bin;
            svg_text(TEXT_LEFT, top + TEXT_BASELINE, to_string(bin));
            svg_rect(TEXT_WIDTH, top, bin_width, BIN_HEIGHT);
            top += BIN_HEIGHT;
        }
        svg_end();
    }
    else{
        float kf = static_cast<double>(IMAGE_WIDTH - TEXT_WIDTH) / (maxbin * BLOCK_WIDTH);
        for (size_t bin : bins) {
            const double bin_width = BLOCK_WIDTH * bin * kf;
            svg_text(TEXT_LEFT, top + TEXT_BASELINE, to_string(bin));
            svg_rect(TEXT_WIDTH, top, bin_width, BIN_HEIGHT);
            top += BIN_HEIGHT;
        }
        svg_end();
    }
}