using System.Diagnostics;
using YLErp.Commons;
using YLErp.Events;

namespace YLErp.Forms
{
    public partial class FormTraceLog : Form
    {
        readonly InnerTraceListener _traceListener;

        public FormTraceLog()
        {
            InitializeComponent();

            _traceListener = new InnerTraceListener(richTextBox1);
            EventBus.Subscribe<TraceEvent>(_traceListener.HandleTraceEvent);
            Trace.Listeners.Clear();
            Trace.Listeners.Add(_traceListener);
        }

        private void FormTraceLog_Load(object sender, EventArgs e)
        {

        }

        private void FormLog_FormClosing(object sender, FormClosingEventArgs e)
        {
            if (e.CloseReason == CloseReason.UserClosing)
            {
                e.Cancel = true;
                Hide();
            }
        }

        private void menuClearLog_Click(object sender, EventArgs e)
        {
            _traceListener.Reset();
        }
    }

    class InnerTraceListener : TraceListener
    {
        const int MaxDataCount = 3000;
        const int MaxDataDiscardCount = 2000;
        const string UrlPrefix = "http://trace/";

        readonly List<object> _datalist;
        readonly RichTextBox _richTextBox;

        int _loopSeq;
        readonly Action<string> _appendTextAction;

        public InnerTraceListener(RichTextBox richTextBox)
        {
            _richTextBox = richTextBox;
            _richTextBox.DetectUrls = true;
            _richTextBox.LinkClicked += richTextBox_LinkClicked;

            _datalist = new List<object>(MaxDataCount + 100);

            _appendTextAction = text => _richTextBox.Text += text;
        }

        private void AppendTextInvoke(string text)
        {
            _richTextBox.BeginInvoke(_appendTextAction, text);
        }

        public void Reset()
        {
            lock (_datalist)
            {
                _loopSeq = 0;
                _datalist.Clear();
                _richTextBox.Clear();
            }
        }

        private void richTextBox_LinkClicked(object sender, LinkClickedEventArgs e)
        {
            if (!e.LinkText.StartsWith(UrlPrefix)) return;

            var text = e.LinkText.Substring(13);
            var index = text.IndexOf('/');
            if (index < 0) return;

            var index2 = text.IndexOf('#', index + 1);

            var left = text.Substring(0, index);
            var right = text.Substring(index + 1, index2 - index - 1);

            lock (_datalist)
            {
                index = (int.Parse(left) - _loopSeq) * 2000 + int.Parse(right);

                if (index >= 0)
                {
                    var json = JsonHelper.Serialize(_datalist[index]);
                    var form = new FormJsonView();
                    form.SetJson(json);
                    form.ShowDialog();
                }
            }
        }

        public override void Write(string message)
        {
            AppendTextInvoke(message);
        }

        public override void WriteLine(string message)
        {
            AppendTextInvoke($"{DateTime.Now:G} [--]{message}{Environment.NewLine}");
        }

        public override void WriteLine(string message, string category)
        {
            AppendTextInvoke($"{DateTime.Now:G} [{category}] {message}{Environment.NewLine}");
        }

        public override void WriteLine(object obj, string category)
        {
            var wrap = obj as TraceDataWrap;
            if (wrap != null)
            {
                obj = wrap.Data;
            }

            if (obj is null)
            {
                AppendTextInvoke($"{DateTime.Now:G} [{category}] {UrlPrefix}null#{wrap?.DataDesc}{Environment.NewLine}");

                return;
            }

            int curSeq = AddData(wrap?.Data ?? obj);

            AppendTextInvoke($"{DateTime.Now:G} [{category}] {UrlPrefix}{_loopSeq}/{curSeq}#{wrap?.DataDesc}{Environment.NewLine}");
        }

        public void HandleTraceEvent(TraceEvent trace)
        {
            if (trace == null) return;

            if (trace.Data != null)
            {
                int curSeq = AddData(trace.Data);
                AppendTextInvoke($"{DateTime.Now:G} [{trace.Category}] {trace.Message} {UrlPrefix}{_loopSeq}/{curSeq}#{trace.DataDesc}{Environment.NewLine}");
            }
            else
            {
                AppendTextInvoke($"{DateTime.Now:G} [{trace.Category}] {trace.Message}{Environment.NewLine}");
            }
        }

        private int AddData(object data)
        {
            if (_datalist.Count > MaxDataCount)
            {
                _loopSeq++;
                _datalist.RemoveRange(0, MaxDataDiscardCount);
            }
            var count = _datalist.Count;
            _datalist.Add(data);
            return count;
        }
    }
}