package com.it_jaros.networkScanner;

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.ReentrantLock;

public class ProgressBar {

    private ScheduledExecutorService ui = Executors.newSingleThreadScheduledExecutor();
    private List<Progress> hosts;
    private ReentrantLock lock = new ReentrantLock();

    public void start() {
        System.out.println("Progress:");
        this.hosts = new ArrayList<>();
        // move cursor down depending on how many hosts have to be scanned
        System.out.print("\n");
        ui.scheduleAtFixedRate(() -> {
            lock.lock();
            drawProgress(false);
            lock.unlock();
        }, 1, 200, TimeUnit.MILLISECONDS);
    }

    private void drawProgress(boolean last) {
        // Make space for drawing of progress bars
        //System.out.print("\u001b[" + hosts.size() + "B");

        // paint a bar per host
        for (Progress progress : hosts) {
            drawBar(progress);
        }

        // move cursor up again
        if (!last)
            System.out.print("\u001b[" + hosts.size() + "A");
    }

    public void submit(Progress progress) {
        lock.lock();
        hosts.add(progress);
        lock.unlock();
    }

    private void drawBar(Progress progress) {
        System.out.print("\u001b[2K\r");
        System.out.println(createBar(
                progress.host(),
                progress.open().get(),
                progress.done().get(),
                progress.total()));
    }

    public String createBar(String label, int open, int done, int total) {
        int width = 30;
        double pct = total == 0 ? 1.0 : (done / (double) total);
        int filled = (int) (pct * width);

        String brackets = "[" + "#".repeat(filled) + "-".repeat(width - filled) + "]";
        int percent = (int) (pct * 100);

        return String.format("%-40s open=%s %s %3d%% (%d/%d)", label, open, brackets, percent, done, total);
    }

    public void stop() {
        ui.shutdown();
        try {
            ui.awaitTermination(10, TimeUnit.SECONDS);
            // we need to draw one last time for the 100% to appear
            drawProgress(true);
        } catch (InterruptedException ignored) {
        }
    }

    void onPortFinished(Progress progress) {
        progress.done().incrementAndGet();
    }

    public void onPortOpen(Progress progress) {
        progress.open().incrementAndGet();
    }
}