using System;
using System.Diagnostics;
using System.Text;

internal sealed class StatusReporter
{
    private int _dotCounter = 0;
    private string _lastMessage = string.Empty;
    private DateTime _lastWriteTime = DateTime.MinValue;

    public void Show(string message, bool withDots = false)
    {
        if (withDots)
        {
            _dotCounter++;
            message = $"{message}{Dots()}";
        }
        Write(message, newline: false);
    }

    public string Dots()
    {
        var dots = (_dotCounter % 3) + 1;
        return new string('.', dots);
    }

    public void ShowLine(string message)
    {
        Write(message, newline: true);
    }

    public void ShowProgress(string message, TimeSpan levelElapsed, TimeSpan totalElapsed)
    {
        _dotCounter++;
        var progress = $"{message}{Dots()}({FormatDuration(levelElapsed)} / {FormatDuration(totalElapsed)})";
        Write(progress, newline: false);
    }

    private void Write(string message, bool newline)
    {
        if (_lastMessage == message && !newline) return;
        var now = DateTime.UtcNow;
        // 너무 자주 찍으면 콘솔이 쓸데없이 지저분해지므로,
        // 진행 중 상태는 최소 1초 간격으로만 업데이트한다.
        if (!newline && (now - _lastWriteTime).TotalMilliseconds < 1000)
        {
            return;
        }
        _lastWriteTime = now;
        var pad = string.Empty;
        _lastMessage = message;
        var output = $"\r\u001b[K{message}{pad}";
        if (newline)
        {
            Console.Error.WriteLine(output);
            _lastMessage = string.Empty;
        }
        else
        {
            Console.Error.Write(output);
        }
    }

    public static string FormatDuration(TimeSpan elapsed)
    {
        if (elapsed.TotalHours >= 1)
        {
            return $"{(int)elapsed.TotalHours}h{elapsed.Minutes}m{elapsed.Seconds}s";
        }
        if (elapsed.TotalMinutes >= 1)
        {
            return $"{(int)elapsed.TotalMinutes}m{elapsed.Seconds}s";
        }
        return $"{elapsed.Seconds}s";
    }
}