using log4net;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Web;
using System.Xml;

public class DebugInfo
{
    private static string basePath;

    private static bool isInit;
    private static object obj = new object();

    public static string DebugString { get; private set; }
    public static string BranchName { get; private set; }
    public const string TemplateName = "change.log";
    public const string DataName = "changelog.xml";
    public const string ResultName = "changelog.txt";


    public static void Init()
    {

        if (isInit) return;

        lock (obj)
        {
            if (isInit) return;

            try
            {
                basePath = HttpContext.Current.Server.MapPath("~/");
                DebugString = GetStaticDebugString();
                isInit = true;
            }
            catch (Exception)
            {

            }
        }
    }

    public static string GetStaticDebugString()
    {
        var ChangeLogFilePath = Path.Combine(basePath, DataName);
        var ResultNameFilePath = Path.Combine(basePath, ResultName);

        if (File.Exists(ResultNameFilePath))
        {
            if (File.ReadAllText(ResultNameFilePath, Encoding.Default) != "")
            {
                return File.ReadAllText(ResultNameFilePath);
            }
        }

        if (!File.Exists(ChangeLogFilePath)) {
            return "changelog.xml doesn't exist";
        }

        var ChangeLogPatternFilePath = Path.Combine(basePath, TemplateName);

        var xmlLog = new XmlDocument();
        xmlLog.Load(ChangeLogFilePath);

        var logs = xmlLog.SelectNodes("//lastBuiltRevision");
        if (logs == null) return "";
        var nodes = logs.Cast<XmlNode>().ToList();

        try
        {
            var fileContent = File.ReadAllText(ChangeLogPatternFilePath, Encoding.Default);

            var lastCommitIDNode = nodes.LastOrDefault();
            var branchNameNode = lastCommitIDNode;

            if (lastCommitIDNode != null)
            {
                var lastCommitID = lastCommitIDNode.SelectSingleNode("SHA1");
                if (lastCommitID != null)
                {
                    fileContent = fileContent.Replace("{RevisionLast}", lastCommitID.InnerText);
                }
            }
            else
            {
                fileContent = fileContent.Replace("{RevisionLast}", "");
            }
            if (branchNameNode != null)
            {
                var branchName = branchNameNode.SelectSingleNode(".//name");
                if (branchName != null)
                {
                    fileContent = fileContent.Replace("{BranchName}", branchName.InnerText);
                }
            }
            else
            {
                fileContent = fileContent.Replace("{BranchName}", "");
            }

            File.WriteAllText(ResultNameFilePath, fileContent);

            return fileContent;
        }
        catch (Exception e)
        {
            LogManager.GetLogger("ASC.DebugInfo").Error("DebugInfo", e);
            return "e.Message: " + e.Message;
        }
        return "";
    }

    private static bool IsServiceLogItem(string log)
    {
        return Regex.IsMatch(log, "(^Merged)|(^Sql)", RegexOptions.IgnoreCase);
    }
}