using log4net.Appender;
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Windows.Forms;

namespace CVE.LogViewer
{
    class DataGridViewAppender : AppenderSkeleton
    {
        private DataGridView _dataGridView;
        public DataGridView AppenderControl
        {
            get
            {
                return _dataGridView;
            }
            set
            {
                _dataGridView = value;
            }
        }
        public string FormName { get; set; }
        public string ListViewName { get; set; }
        /// <summary>
        /// 查找控件
        /// </summary>
        /// <param name="root"></param>
        /// <param name="ListViewName"></param>
        /// <returns></returns>
        private Control FindControlRecursive(Control root, string ListViewName)
        {
            if (root.Name == ListViewName) return root;
            foreach (Control c in root.Controls)
            {
                Control t = FindControlRecursive(c, ListViewName);
                if (t != null) return t;
            }
            return null;
        }

        /// <summary>
        /// 显示日志
        /// </summary>
        /// <param name="loggingEvent"></param>
        protected override void Append(log4net.Core.LoggingEvent loggingEvent)
        {
            //验证控件是否存在
            if (_dataGridView == null)
            {
                if (String.IsNullOrEmpty(FormName) ||
                    String.IsNullOrEmpty(ListViewName))
                    return;

                Form form = Application.OpenForms[FormName];
                if (form == null)
                    return;

                _dataGridView = (DataGridView)FindControlRecursive(form, ListViewName);

                _dataGridView.Invoke(new Action(() =>
                {
                    _dataGridView.Rows.Clear();
                    DataGridViewTextBoxColumn logInfo = new DataGridViewTextBoxColumn();
                    logInfo.Name = "Log Info";
                    logInfo.DataPropertyName = "Log Info";
                    logInfo.HeaderText = "Log Info";
                    _dataGridView.Columns.Add(logInfo);
                    _dataGridView.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.Fill;
                    //设置自动换行
                    _dataGridView.DefaultCellStyle.WrapMode = DataGridViewTriState.True;
                    //设置自动调整高度
                    _dataGridView.AutoSizeRowsMode = DataGridViewAutoSizeRowsMode.AllCells;
                    _dataGridView.RowHeadersVisible = false;
                    _dataGridView.ColumnHeadersVisible = false;
                    _dataGridView.AllowDrop = false;
                    _dataGridView.AllowUserToAddRows = false;
                    _dataGridView.AllowUserToDeleteRows = false;
                    _dataGridView.AllowUserToOrderColumns = false;
                    _dataGridView.AllowUserToResizeColumns = false;
                    _dataGridView.AllowUserToResizeRows = false;
                    _dataGridView.MultiSelect = false;
                    _dataGridView.ReadOnly = true;
                    _dataGridView.CellBorderStyle = DataGridViewCellBorderStyle.None;
                    if (_dataGridView == null)
                        return;

                    form.FormClosing += (s, e) => _dataGridView = null;
                }));                
            }
            if (!_dataGridView.IsHandleCreated)
            {
                return;
            }

            if (_dataGridView.IsDisposed)
            {
                return;
            }

            //显示日志
            string str = String.Format("{0} {1}", loggingEvent.TimeStamp.ToString("yyyy/MM/dd HH:mm:ss.fff"), RenderLoggingEvent(loggingEvent));
            string level = loggingEvent.Level.ToString();

            _dataGridView.BeginInvoke((MethodInvoker)delegate
            {
                //日志行数控制
                if (_dataGridView.Rows.Count > 500)
                {
                    //大于200行清空显示
                    _dataGridView.Rows.Clear();
                }
                DataGridViewRow row = new DataGridViewRow();
             
                DataGridViewTextBoxCell cell = new DataGridViewTextBoxCell();
                cell.Value = str;
                //根据等级控制显示颜色
                switch (level)
                {
                    case "DEBUG":
                        cell.Style.ForeColor = Color.Blue; //DarkBlue;
                        break;
                    case "INFO":
                        cell.Style.ForeColor = Color.Black; //ForestGreen;
                        break;
                    case "WARN":
                        cell.Style.ForeColor = Color.Orange;
                        break;
                    case "ERROR":
                        cell.Style.ForeColor = Color.MediumVioletRed;
                        break;
                    case "FATAL":
                        cell.Style.ForeColor = Color.Red;
                        break;
                }
                row.Cells.Add(cell);
                //控制每次显示最新行
                _dataGridView.Rows.Add(row);
                _dataGridView.FirstDisplayedScrollingRowIndex = _dataGridView.Rows.Count - 1;
                _dataGridView.ClearSelection();
            });
        }
    }
}