cs-lab34/svg.cpp

#include <iostream>
#include <vector>
#include <string>
#include "svg.h"
using namespace std;

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;

double ask_width(size_t numbers_count, std::istream& input) {
    while (true) {
        double width;
        cerr << "Write width ";
        input >> width;
        if (width < 70) {
            cout << "Try again. It's too low.\n";
        } else if (width > 800) {
            cout << "Try again. It's too high.\n";
        } else if (width < numbers_count * BLOCK_WIDTH / 3) {
            cout << "Try again.\n";
        } else {
            return width;
        }
    }
}

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>\n";
}

void svg_rect(double x, double y, double width, double height, string stroke = "black", string fill = "aaaaaa") {
    cout << "<rect x='" << x << "' y='" << y << "' width='" << width << "' height='" << height << "' stroke='" << stroke << "' fill='" << fill << "' />\n";
}

void show_histogram_svg(const vector<size_t>& bins) {
    const auto IMAGE_WIDTH = ask_width(bins.size(), cin);
    const auto MAX_WIDTH = IMAGE_WIDTH - TEXT_WIDTH;
    size_t max_count = 0;
    for (size_t count : bins) {
        if (count > max_count) {
            max_count = count;
        }
    }
    if (max_count == 0) {
        max_count = 1;
    }
    auto scale_factor = static_cast<double>(MAX_WIDTH) / (max_count * BLOCK_WIDTH);
    if (scale_factor > 1) {
        scale_factor = 1;
    }

    svg_begin(IMAGE_WIDTH, IMAGE_HEIGHT);
    double top = 0;
    for (size_t bin : bins) {
        double bin_width = BLOCK_WIDTH * bin * scale_factor;
        svg_text(TEXT_LEFT, top + TEXT_BASELINE, to_string(bin));
        svg_rect(TEXT_WIDTH, top, bin_width, BIN_HEIGHT);
        top += BIN_HEIGHT;
    }
    svg_end();
}