using Sarand.Net.Standard.Base.App;
using System;
using System.Text.RegularExpressions;

namespace Sarand.Net.Standard.Base.Utils
{
	//=======================================================================
	public static class FtpUtil
	{
		//-------------------------------------------------------------------
		/// <summary>Cleanse the folder name - delimit with '/', remove duplicate, leading and trailing delimiters. </summary>
		public static String CleansePath (String path)
		{
			return path.ReplaceAll("\\", "/").ReplaceAll("//", "/").TrimStart('/').TrimEnd('/');
		}

		//-------------------------------------------------------------------
		/// <summary>Retrieve parent folder for folder. Parent for top level folder is blank. </summary>
		public static String GetParentFolder (String folder)
		{
			String parentFolder = "";
			String[] folders = CleansePath(folder).Split('/');
			if (folders.Length > 0)
				parentFolder = String.Join("/", folders, 0, folders.Length - 1);
			return parentFolder;
		}

		//-------------------------------------------------------------------
		/// <summary>Retrieve bottom level item name from path. Parent for top level folder is blank. </summary>
		public static String GetItemName (String folder)
		{
			String[] folders = CleansePath(folder).Split('/');
			if (folders.Length >= 0)
				return folders[folders.Length - 1];
			return "";
		}

		//-------------------------------------------------------------------
		public class FtpDirectoryItem
		{
			public String Attr { get; set; } = "";
			public bool IsDirectory { get; set; }
			public String Owner { get; set; } = "";
			public String Group { get; set; } = "";
			public int Links { get; set; }
			public long Size { get; set; }
			public int Day { get; set; }
			public int Month { get; set; }
			public String MonthName { get; set; } = "";
			public int Year { get; set; }
			public String Time { get; set; } = "";
			public DateTime Modified { get; set; }
			public String Name { get; set; } = "";
		}
		// YangMing (Unix?) format:
		//   08-03-18  10:10AM       <DIR>          SolentInboundTest
		//   08-03-18  10:10AM       <DIR>          SolentOutboundTest
		//   08-03-18  11:23AM              8507075 testDataWithRatherLongFilename.zip
		//   08-03-18  11:17AM                   22 test.txt
		public static readonly Regex DirectoryListPattern_Unix = new Regex(@"^"+
				// 1. Month.
				@"(\d{2})-"+
				// 2. Day of month.
				@"(\d{2})-"+
				// 3. Year.
				@"(\d{2})\s+"+
				// 4. Time.
				@"(\d{2}:\d{2})"+
				// 5. Time period.
				@"(\w{2})\s+"+
				// 6. Directory indicator or Filesize.
				@"(<DIR>|\d+)\s+"+
				// Name.
				@"([^\s]+)$",
				RegexOptions.IgnoreCase);
		// Windows/DOS format:
		//   drwx------   3 user group            0 Apr 10 07:47 test
		//   -rw - r--r-- 1 ftp ftp        5592560 Feb 26 18:53 DamonJenkinsA_84_C_CTS.dds
		// Update date format:
		//    MMM dd HH:mm  if the file was modified in the last six months
		//    MMM dd yyyy     otherwise.
		public static readonly Regex DirectoryListPattern_Windows = new Regex(@"^"+
				// 1. Attributes.
				// 1st Character: '-' file. 'b' Block special file. 'c' Character special file. 'd' directory. 'l' link. 'n' Network file. 'p' FIFO. 's' Socket.
				// Attributes: r Permission to read file. w Permission to write to file. x Permission to execute file. a Archive bit is on (file has not been backed up).
				//             c Compressed file. s System file. h Hidden file. t Temporary file.
				@"([abcdhlnprstwx-]{10})\s+" +
				// 2. Number of links to ths file.
				@"(\d+)\s+"+
				// 3. Owner.
				@"([^\s]+)\s+"+
				// 4. Group.
				@"([^\s]+)\s+"+
				// 5. Size.
				@"(\d+)\s+"+
				// 6. Month.
				@"(\w{3})\s+"+
				// 7. Day of month.
				@"(\d{1,2})\s+"+
				// 8. Time or Year.
				@"(\d{4}|\d\d:\d\d)\s+"+
				// Name.
				@"(.+)$",
				RegexOptions.IgnoreCase);
		/// <summary>Extract details from Directory detail list item.</summary>
		public static FtpDirectoryItem GetDirectoryItem (String directoryItemData)
		{
			if (StringUtil.IsEmpty(StringUtil.EmptyOnNull(directoryItemData).Trim())) return null;

			// Check for Unix directory listing pattern.
			Match match = DirectoryListPattern_Unix.Match(directoryItemData);
			if (match.Success && match.Groups.Count == 8)
			{
				FtpDirectoryItem directoryItem = new FtpDirectoryItem();
				directoryItem.Month = StringUtil.ToInt(match.Groups[1].Value);
				directoryItem.Day = StringUtil.ToInt(match.Groups[2].Value);
				directoryItem.Year = StringUtil.ToInt(match.Groups[3].Value);
				String directoryOrFileSize = match.Groups[6].Value;
				if (directoryOrFileSize.EqualsCI("<DIR>"))
					directoryItem.IsDirectory = true;
				else
					directoryItem.Size = StringUtil.ToLong(directoryOrFileSize);
				directoryItem.Name = match.Groups[7].Value;
				return directoryItem;
			}

			// Check for Windows directory listing pattern.
			match = DirectoryListPattern_Windows.Match(directoryItemData);
			if (match.Success && match.Groups.Count == 10)
			{
				FtpDirectoryItem directoryItem = new FtpDirectoryItem();
				directoryItem.Attr = match.Groups[1].Value;
				directoryItem.IsDirectory = StringUtil.Left(directoryItem.Attr, 1).EqualsCI("d");
				directoryItem.Links = StringUtil.ToInt(match.Groups[2].Value);
				directoryItem.Owner = match.Groups[3].Value;
				directoryItem.Group = match.Groups[4].Value;
				directoryItem.Size = StringUtil.ToInt(match.Groups[5].Value);
				directoryItem.MonthName = match.Groups[6].Value;
				directoryItem.Day = StringUtil.ToInt(match.Groups[7].Value);
				String timeYear = match.Groups[8].Value;
				if (StringUtil.IsNumeric(timeYear))
					directoryItem.Year = StringUtil.ToInt(timeYear);
				directoryItem.Name = match.Groups[9].Value;
				return directoryItem;
			}

			// Log failure.
			SaLogger.Warn("FtpUtils.GetDirectoryItem Parse Failed: '" + directoryItemData + "'", true);
			return null;
		}

		//-------------------------------------------------------------------
	}
	//=======================================================================
}