using System;
using System.Collections.ObjectModel;
using System.Reactive.Disposables;
using System.Reactive.Subjects;
using System.Text;
using System.Windows.Data;
using DynamicData;
using DynamicData.Binding;
using Microsoft.Extensions.Logging;
using NLog;
using NLog.Targets;
using LogLevel = NLog.LogLevel;

namespace Wabbajack.Models;

public class LogStream : TargetWithLayout
{

    private readonly SourceCache<ILogMessage, long> _messageLog = new(x => x.MessageId);
    private readonly Subject<ILogMessage> _messages = new();
    
    public readonly ReadOnlyObservableCollection<ILogMessage> _messagesFiltered;
    private readonly CompositeDisposable _disposables;
    public ReadOnlyObservableCollection<ILogMessage> MessageLog => _messagesFiltered;
    public IObservable<ILogMessage> Messages => _messages;
    

    public LogStream()
    {
        _disposables = new CompositeDisposable();
        _messageLog.Connect()
            .Bind(out _messagesFiltered)
            .Subscribe()
            .DisposeWith(_disposables);
        
        Messages
            .ObserveOnGuiThread()
            .Subscribe(m => _messageLog.AddOrUpdate(m))
            .DisposeWith(_disposables);

        _messages.DisposeWith(_disposables);
    }

    protected override void Dispose(bool disposing)
    {
        if (disposing)
            _disposables.Dispose();
    }

    protected override void Write(LogEventInfo logEvent)
    {
        _messages.OnNext(new LogMessage(logEvent));
    }
    public interface ILogMessage
    {
        long MessageId { get; }

        string ShortMessage { get; }
        DateTime TimeStamp { get; }
        string LongMessage { get; }
    }

    private record LogMessage(LogEventInfo info) : ILogMessage
    {
        public long MessageId => info.SequenceID;
        public string ShortMessage => info.FormattedMessage;
        public DateTime TimeStamp => info.TimeStamp;
        public string LongMessage => info.FormattedMessage;
    }
    
}