using System;
using System.Diagnostics;
using Neo.Afx.ComponentModel;

namespace Neo.Afx.Diagnostics
{
    /// <summary>
    /// A logging utility.
    /// <remarks>
    /// The <see cref="AfxLogSource"/> must be created once off before this utility is first used.
    /// Use the <code>Neo.Afx.Utils.EventSourceGenerator</code> to do this.
    /// </remarks>
    /// </summary>
    public static class LogUtility
    {
        /// <summary>
        /// The log source which is "neo AFX" in the Application event log.
        /// </summary>
        public const string AfxLogSource = "neo AFX";

        #region WriteApplicationEventLog - AfxLogSource

        /// <summary>
        /// A helper function that writes exception detail to the <see cref="AfxLogSource"/>.
        /// </summary>
        /// <param name="e">The exception to be logged.</param>
        public static void WriteApplicationEventLog(Exception e)
        {
            WriteApplicationEventLog(e, 0);
        }

        /// <summary>
        /// A helper function that writes exception detail to the <see cref="AfxLogSource"/>.
        /// </summary>
        /// <param name="e">The exception to be logged.</param>
        /// <param name="eventID">The application-specific identifier for the event.</param>
        public static void WriteApplicationEventLog(Exception e, int eventID)
        {
            WriteApplicationEventLog(EventLogEntryType.Error, eventID, e.ToStringComplete());
        }

        /// <summary>
        /// A helper function that writes a message to the <see cref="AfxLogSource"/>.
        /// </summary>
        /// <param name="entryType">The type of event log entry.</param>
        /// <param name="eventID">The application-specific identifier for the event.</param>
        /// <param name="format">The format string.</param>
        /// <param name="args">The arguments to the <paramref name="format"/>.</param>
        public static void WriteApplicationEventLog(EventLogEntryType entryType, int eventID, string format, params object[] args)
        {
            EventLog.WriteEntry(AfxLogSource, string.Format(format, args), entryType, eventID);
        }

        #endregion

        #region WriteApplicationEventLog

        /// <summary>
        /// A helper function that writes exception detail to the <paramref name="logSource"/>.
        /// </summary>
        /// <param name="logSource">The log source for the event.</param>
        /// <param name="e">The exception to be logged.</param>
        public static void WriteApplicationEventLog(string logSource, Exception e)
        {
            WriteApplicationEventLog(logSource, e, 0);
        }

        /// <summary>
        /// A helper function that writes exception detail to the <paramref name="logSource"/>.
        /// </summary>
        /// <param name="logSource">The log source for the event.</param>
        /// <param name="e">The exception to be logged.</param>
        /// <param name="eventID">The application-specific identifier for the event.</param>
        public static void WriteApplicationEventLog(string logSource, Exception e, int eventID)
        {
            EventLog.WriteEntry(logSource, e.ToStringComplete(), EventLogEntryType.Error, eventID);
        }

        /// <summary>
        /// A helper function that writes a message to the <paramref name="logSource"/>.
        /// </summary>
        /// <param name="logSource">The log source for the event.</param>
        /// <param name="entryType">The type of event log entry.</param>
        /// <param name="format">The format string.</param>
        /// <param name="args">The arguments to the <paramref name="format"/>.</param>
        public static void WriteApplicationEventLog(string logSource, EventLogEntryType entryType, string format, params object[] args)
        {
            WriteApplicationEventLog(logSource, entryType, 0, format, args);
        }

        /// <summary>
        /// A helper function that writes a message to the <paramref name="logSource"/>.
        /// </summary>
        /// <param name="logSource">The log source for the event.</param>
        /// <param name="entryType">The type of event log entry.</param>
        /// <param name="eventID">The application-specific identifier for the event.</param>
        /// <param name="format">The format string.</param>
        /// <param name="args">The arguments to the <paramref name="format"/>.</param>
        public static void WriteApplicationEventLog(string logSource, EventLogEntryType entryType, int eventID, string format, params object[] args)
        {
            EventLog.WriteEntry(logSource, string.Format(format, args), entryType, eventID);
        }

        #endregion

        #region WriteTrace

        /// <summary>
        /// Writes a time-stamped to the trace file.
        /// </summary>
        /// <param name="source">The source of the trace.</param>
        /// <param name="message">The message to be written.</param>        
        public static void WriteTrace(string source, string message)
        {
            Trace.WriteLine(
                String.Format("{0} {1} - {2}", DateTime.Now.ToString("yyyy.MM.dd HH:mm:ss"), source, message));
        }

        #endregion

    }
}