using System.ComponentModel;
using System.Runtime.CompilerServices;

namespace VideoDownloader.Browser;

/// <summary>T3-15: "파라미터 제거 복사" — 추적용 쿼리·프래그먼트를 뺀 URL 반환.</summary>
public static class UrlCleaner
{
    public static string? StripQuery(string? url)
    {
        if (url == null) return null;
        var q = url.IndexOf('?');
        if (q >= 0) url = url[..q];
        var f = url.IndexOf('#');
        if (f >= 0) url = url[..f];
        return url;
    }
}

/// <summary>T3-15: 주소창 진행 바 상태 — 진행 중 네비게이션 개수 집계(탭·리다이렉트 중복 안전).</summary>
public sealed class NavProgressTracker : INotifyPropertyChanged
{
    private int _count;

    public bool IsNavigating => Volatile.Read(ref _count) > 0;

    public event PropertyChangedEventHandler? PropertyChanged;

    public void Started() => Update(1);
    public void Completed() => Update(-1);

    private void Update(int delta)
    {
        var before = IsNavigating;
        var c = _count + delta;
        Volatile.Write(ref _count, Math.Max(0, c)); // 과잉 완료 방지
        if (before != IsNavigating)
            OnPropertyChanged(nameof(IsNavigating));
    }

    private void OnPropertyChanged([CallerMemberName] string? name = null) =>
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));
}