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

using SabreTools.Library.Data;
using SabreTools.Library.DatItems;
using SabreTools.Library.Tools;

#if MONO
using System.IO;
#else
using Alphaleonis.Win32.Filesystem;

using FileStream = System.IO.FileStream;
using StreamWriter = System.IO.StreamWriter;
#endif
using NaturalSort;

namespace SabreTools.Library.DatFiles
{
	/// <summary>
	/// Represents parsing and writing of an SabreDat XML DAT
	/// </summary>
	/// TODO: Verify that all write for this DatFile type is correct
	internal class SabreDat : DatFile
	{
		/// <summary>
		/// Constructor designed for casting a base DatFile
		/// </summary>
		/// <param name="datFile">Parent DatFile to copy from</param>
		public SabreDat(DatFile datFile)
			: base(datFile, cloneHeader: false)
		{
		}

		/// <summary>
		/// Parse an SabreDat XML DAT and return all found directories and files within
		/// </summary>
		/// <param name="filename">Name of the file to be parsed</param>
		/// <param name="sysid">System ID for the DAT</param>
		/// <param name="srcid">Source ID for the DAT</param>
		/// <param name="keep">True if full pathnames are to be kept, false otherwise (default)</param>
		/// <param name="clean">True if game names are sanitized, false otherwise (default)</param>
		/// <param name="remUnicode">True if we should remove non-ASCII characters from output, false otherwise (default)</param>
		public override void ParseFile(
			// Standard Dat parsing
			string filename,
			int sysid,
			int srcid,

			// Miscellaneous
			bool keep,
			bool clean,
			bool remUnicode)
		{
			// Prepare all internal variables
			bool empty = true;
			string key = "";
			List<string> parent = new List<string>();

			Encoding enc = Utilities.GetEncoding(filename);
			XmlReader xtr = Utilities.GetXmlTextReader(filename);

			// If we got a null reader, just return
			if (xtr == null)
			{
				return;
			}

			// Otherwise, read the file to the end
			try
			{
				xtr.MoveToContent();
				while (!xtr.EOF)
				{
					// If we're ending a folder or game, take care of possibly empty games and removing from the parent
					if (xtr.NodeType == XmlNodeType.EndElement && (xtr.Name == "directory" || xtr.Name == "dir"))
					{
						// If we didn't find any items in the folder, make sure to add the blank rom
						if (empty)
						{
							string tempgame = String.Join("\\", parent);
							Rom rom = new Rom("null", tempgame, omitFromScan: Hash.DeepHashes); // TODO: All instances of Hash.DeepHashes should be made into 0x0 eventually

							// Now process and add the rom
							key = ParseAddHelper(rom, clean, remUnicode);
						}

						// Regardless, end the current folder
						int parentcount = parent.Count;
						if (parentcount == 0)
						{
							Globals.Logger.Verbose("Empty parent '{0}' found in '{1}'", String.Join("\\", parent), filename);
							empty = true;
						}

						// If we have an end folder element, remove one item from the parent, if possible
						if (parentcount > 0)
						{
							parent.RemoveAt(parent.Count - 1);
							if (keep && parentcount > 1)
							{
								Type = (String.IsNullOrWhiteSpace(Type) ? "SuperDAT" : Type);
							}
						}
					}

					// We only want elements
					if (xtr.NodeType != XmlNodeType.Element)
					{
						xtr.Read();
						continue;
					}

					switch (xtr.Name)
					{
						// We want to process the entire subtree of the header
						case "header":
							ReadHeader(xtr.ReadSubtree(), keep);

							// Skip the header node now that we've processed it
							xtr.Skip();
							break;
						case "dir":
						case "directory":
							empty = ReadDirectory(xtr.ReadSubtree(), parent, filename, sysid, srcid, keep, clean, remUnicode);

							// Skip the directory node now that we've processed it
							xtr.Read();
							break;
						default:
							xtr.Read();
							break;
					}
				}
			}
			catch (Exception ex)
			{
				Globals.Logger.Warning("Exception found while parsing '{0}': {1}", filename, ex);

				// For XML errors, just skip the affected node
				xtr?.Read();
			}

			xtr.Dispose();
		}

		/// <summary>
		/// Read header information
		/// </summary>
		/// <param name="reader">XmlReader to use to parse the header</param>
		/// <param name="keep">True if full pathnames are to be kept, false otherwise (default)</param>
		private void ReadHeader(XmlReader reader, bool keep)
		{
			bool superdat = false;

			// If there's no subtree to the header, skip it
			if (reader == null)
			{
				return;
			}

			// Otherwise, read what we can from the header
			while (!reader.EOF)
			{
				// We only want elements
				if (reader.NodeType != XmlNodeType.Element || reader.Name == "header")
				{
					reader.Read();
					continue;
				}

				// Get all header items (ONLY OVERWRITE IF THERE'S NO DATA)
				string content = "";
				switch (reader.Name)
				{
					case "name":
						content = reader.ReadElementContentAsString(); ;
						Name = (String.IsNullOrWhiteSpace(Name) ? content : Name);
						superdat = superdat || content.Contains(" - SuperDAT");
						if (keep && superdat)
						{
							Type = (String.IsNullOrWhiteSpace(Type) ? "SuperDAT" : Type);
						}
						break;
					case "description":
						content = reader.ReadElementContentAsString();
						Description = (String.IsNullOrWhiteSpace(Description) ? content : Description);
						break;
					case "rootdir":
						content = reader.ReadElementContentAsString();
						RootDir = (String.IsNullOrWhiteSpace(RootDir) ? content : RootDir);
						break;
					case "category":
						content = reader.ReadElementContentAsString();
						Category = (String.IsNullOrWhiteSpace(Category) ? content : Category);
						break;
					case "version":
						content = reader.ReadElementContentAsString();
						Version = (String.IsNullOrWhiteSpace(Version) ? content : Version);
						break;
					case "date":
						content = reader.ReadElementContentAsString();
						Date = (String.IsNullOrWhiteSpace(Date) ? content.Replace(".", "/") : Date);
						break;
					case "author":
						content = reader.ReadElementContentAsString();
						Author = (String.IsNullOrWhiteSpace(Author) ? content : Author);
						Email = (String.IsNullOrWhiteSpace(Email) ?	reader.GetAttribute("email") : Email);
						Homepage = (String.IsNullOrWhiteSpace(Homepage) ? reader.GetAttribute("homepage") : Homepage);
						Url = (String.IsNullOrWhiteSpace(Url) ? reader.GetAttribute("url") : Url);
						break;
					case "comment":
						content = reader.ReadElementContentAsString();
						Comment = (String.IsNullOrWhiteSpace(Comment) ? content : Comment);
						break;
					case "flags":
						ReadFlags(reader.ReadSubtree(), superdat);

						// Skip the flags node now that we've processed it
						reader.Skip();
						break;
					default:
						reader.Read();
						break;
				}
			}
		}

		/// <summary>
		/// Read directory information
		/// </summary>
		/// <param name="reader">XmlReader to use to parse the header</param>
		/// <param name="filename">Name of the file to be parsed</param>
		/// <param name="sysid">System ID for the DAT</param>
		/// <param name="srcid">Source ID for the DAT</param>
		/// <param name="keep">True if full pathnames are to be kept, false otherwise (default)</param>
		/// <param name="clean">True if game names are sanitized, false otherwise (default)</param>
		/// <param name="remUnicode">True if we should remove non-ASCII characters from output, false otherwise (default)</param>
		private bool ReadDirectory(XmlReader reader,
			List<string> parent,

			// Standard Dat parsing
			string filename,
			int sysid,
			int srcid,

			// Miscellaneous
			bool keep,
			bool clean,
			bool remUnicode)
		{
			// Prepare all internal variables
			XmlReader flagreader;
			bool empty = true;
			string key = "", date = "";
			long size = -1;
			ItemStatus its = ItemStatus.None;

			// If there's no subtree to the header, skip it
			if (reader == null)
			{
				return empty;
			}

			string foldername = (reader.GetAttribute("name") ?? "");
			if (!String.IsNullOrWhiteSpace(foldername))
			{
				parent.Add(foldername);
			}

			// Otherwise, read what we can from the directory
			while (!reader.EOF)
			{
				// If we're ending a folder or game, take care of possibly empty games and removing from the parent
				if (reader.NodeType == XmlNodeType.EndElement && (reader.Name == "directory" || reader.Name == "dir"))
				{
					// If we didn't find any items in the folder, make sure to add the blank rom
					if (empty)
					{
						string tempgame = String.Join("\\", parent);
						Rom rom = new Rom("null", tempgame, omitFromScan: Hash.DeepHashes); // TODO: All instances of Hash.DeepHashes should be made into 0x0 eventually

						// Now process and add the rom
						key = ParseAddHelper(rom, clean, remUnicode);
					}

					// Regardless, end the current folder
					int parentcount = parent.Count;
					if (parentcount == 0)
					{
						Globals.Logger.Verbose("Empty parent '{0}' found in '{1}'", String.Join("\\", parent), filename);
						empty = true;
					}

					// If we have an end folder element, remove one item from the parent, if possible
					if (parentcount > 0)
					{
						parent.RemoveAt(parent.Count - 1);
						if (keep && parentcount > 1)
						{
							Type = (String.IsNullOrWhiteSpace(Type) ? "SuperDAT" : Type);
						}
					}
				}

				// We only want elements
				if (reader.NodeType != XmlNodeType.Element)
				{
					reader.Read();
					continue;
				}

				// Get all directory items
				string content = "";
				switch (reader.Name)
				{
					// Directories can contain directories
					case "dir":
					case "directory":
						ReadDirectory(reader.ReadSubtree(), parent, filename, sysid, srcid, keep, clean, remUnicode);

						// Skip the directory node now that we've processed it
						reader.Read();
						break;
					case "file":
						empty = false;

						// If the rom is itemStatus, flag it
						its = ItemStatus.None;
						flagreader = reader.ReadSubtree();

						// If the subtree is empty, skip it
						if (flagreader == null)
						{
							reader.Skip();
							continue;
						}

						while (!flagreader.EOF)
						{
							// We only want elements
							if (flagreader.NodeType != XmlNodeType.Element || flagreader.Name == "flags")
							{
								flagreader.Read();
								continue;
							}

							switch (flagreader.Name)
							{
								case "flag":
									if (flagreader.GetAttribute("name") != null && flagreader.GetAttribute("value") != null)
									{
										content = flagreader.GetAttribute("value");
										its = Utilities.GetItemStatus(flagreader.GetAttribute("name"));
									}
									break;
							}

							flagreader.Read();
						}

						// If the rom has a Date attached, read it in and then sanitize it
						date = Utilities.GetDate(reader.GetAttribute("date"));

						// Take care of hex-sized files
						size = Utilities.GetSize(reader.GetAttribute("size"));

						Machine dir = new Machine();

						// Get the name of the game from the parent
						dir.Name = String.Join("\\", parent);
						dir.Description = dir.Name;

						DatItem datItem;
						switch (reader.GetAttribute("type").ToLowerInvariant())
						{
							case "archive":
								datItem = new Archive
								{
									Name = reader.GetAttribute("name"),

									SystemID = sysid,
									System = filename,
									SourceID = srcid,
								};
								break;
							case "biosset":
								datItem = new BiosSet
								{
									Name = reader.GetAttribute("name"),
									Description = reader.GetAttribute("description"),
									Default = Utilities.GetYesNo(reader.GetAttribute("default")),

									SystemID = sysid,
									System = filename,
									SourceID = srcid,
								};
								break;
							case "disk":
								datItem = new Disk
								{
									Name = reader.GetAttribute("name"),
									MD5 = Utilities.CleanHashData(reader.GetAttribute("md5"), Constants.MD5Length),
									SHA1 = Utilities.CleanHashData(reader.GetAttribute("sha1"), Constants.SHA1Length),
									SHA256 = Utilities.CleanHashData(reader.GetAttribute("sha256"), Constants.SHA256Length),
									SHA384 = Utilities.CleanHashData(reader.GetAttribute("sha384"), Constants.SHA384Length),
									SHA512 = Utilities.CleanHashData(reader.GetAttribute("sha512"), Constants.SHA512Length),
									ItemStatus = its,

									SystemID = sysid,
									System = filename,
									SourceID = srcid,
								};
								break;
							case "release":
								datItem = new Release
								{
									Name = reader.GetAttribute("name"),
									Region = reader.GetAttribute("region"),
									Language = reader.GetAttribute("language"),
									Date = reader.GetAttribute("date"),
									Default = Utilities.GetYesNo(reader.GetAttribute("default")),

									SystemID = sysid,
									System = filename,
									SourceID = srcid,
								};
								break;
							case "rom":
								datItem = new Rom
								{
									Name = reader.GetAttribute("name"),
									Size = size,
									CRC = Utilities.CleanHashData(reader.GetAttribute("crc"), Constants.CRCLength),
									MD5 = Utilities.CleanHashData(reader.GetAttribute("md5"), Constants.MD5Length),
									SHA1 = Utilities.CleanHashData(reader.GetAttribute("sha1"), Constants.SHA1Length),
									SHA256 = Utilities.CleanHashData(reader.GetAttribute("sha256"), Constants.SHA256Length),
									SHA384 = Utilities.CleanHashData(reader.GetAttribute("sha384"), Constants.SHA384Length),
									SHA512 = Utilities.CleanHashData(reader.GetAttribute("sha512"), Constants.SHA512Length),
									ItemStatus = its,
									Date = date,

									SystemID = sysid,
									System = filename,
									SourceID = srcid,
								};
								break;
							case "sample":
								datItem = new Sample
								{
									Name = reader.GetAttribute("name"),

									SystemID = sysid,
									System = filename,
									SourceID = srcid,
								};
								break;
							default:
								// By default, create a new Blank, just in case
								if (this.KeepEmptyGames)
								{
									datItem = new Blank();
								}
								else
								{
									datItem = null;
								}
								break;
						}

						datItem?.CopyMachineInformation(dir);

						// Now process and add the rom
						key = ParseAddHelper(datItem, clean, remUnicode);

						reader.Read();
						break;
				}
			}

			return empty;
		}

		/// <summary>
		/// Read flags information
		/// </summary>
		/// <param name="reader">XmlReader to use to parse the header</param>
		/// <param name="superdat">True if superdat has already been set externally, false otherwise</param>
		private void ReadFlags(XmlReader reader, bool superdat)
		{
			// Prepare all internal variables
			string content = "";

			// If we somehow have a null flag section, skip it
			if (reader == null)
			{
				return;
			}

			while (!reader.EOF)
			{
				// We only want elements
				if (reader.NodeType != XmlNodeType.Element || reader.Name == "flags")
				{
					reader.Read();
					continue;
				}

				switch (reader.Name)
				{
					case "flag":
						if (reader.GetAttribute("name") != null && reader.GetAttribute("value") != null)
						{
							content = reader.GetAttribute("value");
							switch (reader.GetAttribute("name").ToLowerInvariant())
							{
								case "type":
									Type = (String.IsNullOrWhiteSpace(Type) ? content : Type);
									superdat = superdat || content.Contains("SuperDAT");
									break;
								case "forcemerging":
									if (ForceMerging == ForceMerging.None)
									{
										ForceMerging = Utilities.GetForceMerging(content);
									}
									break;
								case "forcenodump":
									if (ForceNodump == ForceNodump.None)
									{
										ForceNodump = Utilities.GetForceNodump(content);
									}
									break;
								case "forcepacking":
									if (ForcePacking == ForcePacking.None)
									{
										ForcePacking = Utilities.GetForcePacking(content);
									}
									break;
							}
						}
						reader.Read();
						break;
					default:
						reader.Read();
						break;
				}
			}
		}

		/// <summary>
		/// Create and open an output file for writing direct from a dictionary
		/// </summary>
		/// <param name="outfile">Name of the file to write to</param>
		/// <param name="ignoreblanks">True if blank roms should be skipped on output, false otherwise (default)</param>
		/// <returns>True if the DAT was written correctly, false otherwise</returns>
		/// TODO: Fix writing out files that have a path in the name
		public override bool WriteToFile(string outfile, bool ignoreblanks = false)
		{
			try
			{
				Globals.Logger.User("Opening file for writing: {0}", outfile);
				FileStream fs = Utilities.TryCreate(outfile);

				// If we get back null for some reason, just log and return
				if (fs == null)
				{
					Globals.Logger.Warning("File '{0}' could not be created for writing! Please check to see if the file is writable", outfile);
					return false;
				}

				StreamWriter sw = new StreamWriter(fs, new UTF8Encoding(false));

				// Write out the header
				WriteHeader(sw);

				// Write out each of the machines and roms
				int depth = 2, last = -1;
				string lastgame = null;
				List<string> splitpath = new List<string>();

				// Get a properly sorted set of keys
				List<string> keys = Keys;
				keys.Sort(new NaturalComparer());

				foreach (string key in keys)
				{
					List<DatItem> roms = this[key];

					// Resolve the names in the block
					roms = DatItem.ResolveNames(roms);

					for (int index = 0; index < roms.Count; index++)
					{
						DatItem rom = roms[index];

						// There are apparently times when a null rom can skip by, skip them
						if (rom.Name == null || rom.MachineName == null)
						{
							Globals.Logger.Warning("Null rom found!");
							continue;
						}

						List<string> newsplit = rom.MachineName.Split('\\').ToList();

						// If we have a different game and we're not at the start of the list, output the end of last item
						if (lastgame != null && lastgame.ToLowerInvariant() != rom.MachineName.ToLowerInvariant())
						{
							depth = WriteEndGame(sw, splitpath, newsplit, depth, out last);
						}

						// If we have a new game, output the beginning of the new item
						if (lastgame == null || lastgame.ToLowerInvariant() != rom.MachineName.ToLowerInvariant())
						{
							depth = WriteStartGame(sw, rom, newsplit, lastgame, depth, last);
						}

						// If we have a "null" game (created by DATFromDir or something similar), log it to file
						if (rom.Type == ItemType.Rom
							&& ((Rom)rom).Size == -1
							&& ((Rom)rom).CRC == "null")
						{
							Globals.Logger.Verbose("Empty folder found: {0}", rom.MachineName);

							splitpath = newsplit;
							lastgame = rom.MachineName;
							continue;
						}

						// Now, output the rom data
						WriteDatItem(sw, rom, depth, ignoreblanks);

						// Set the new data to compare against
						splitpath = newsplit;
						lastgame = rom.MachineName;
					}
				}

				// Write the file footer out
				WriteFooter(sw, depth);

				Globals.Logger.Verbose("File written!" + Environment.NewLine);
				sw.Dispose();
				fs.Dispose();
			}
			catch (Exception ex)
			{
				Globals.Logger.Error(ex.ToString());
				return false;
			}

			return true;
		}

		/// <summary>
		/// Write out DAT header using the supplied StreamWriter
		/// </summary>
		/// <param name="sw">StreamWriter to output to</param>
		/// <returns>True if the data was written, false on error</returns>
		private bool WriteHeader(StreamWriter sw)
		{
			try
			{
				string header = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
							"<!DOCTYPE sabredat SYSTEM \"newdat.xsd\">\n\n" +
							"<datafile>\n" +
							"\t<header>\n" +
							"\t\t<name>" + HttpUtility.HtmlEncode(Name) + "</name>\n" +
							"\t\t<description>" + HttpUtility.HtmlEncode(Description) + "</description>\n" +
							(!String.IsNullOrWhiteSpace(RootDir) ? "\t\t<rootdir>" + HttpUtility.HtmlEncode(RootDir) + "</rootdir>\n" : "") +
							(!String.IsNullOrWhiteSpace(Category) ? "\t\t<category>" + HttpUtility.HtmlEncode(Category) + "</category>\n" : "") +
							"\t\t<version>" + HttpUtility.HtmlEncode(Version) + "</version>\n" +
							(!String.IsNullOrWhiteSpace(Date) ? "\t\t<date>" + HttpUtility.HtmlEncode(Date) + "</date>\n" : "") +
							"\t\t<author>" + HttpUtility.HtmlEncode(Author) + "</author>\n" +
							(!String.IsNullOrWhiteSpace(Comment) ? "\t\t<comment>" + HttpUtility.HtmlEncode(Comment) + "</comment>\n" : "") +
							(!String.IsNullOrWhiteSpace(Type) || ForcePacking != ForcePacking.None || ForceMerging != ForceMerging.None || ForceNodump != ForceNodump.None ?
								"\t\t<flags>\n" +
									(!String.IsNullOrWhiteSpace(Type) ? "\t\t\t<flag name=\"type\" value=\"" + HttpUtility.HtmlEncode(Type) + "\"/>\n" : "") +
									(ForcePacking == ForcePacking.Unzip ? "\t\t\t<flag name=\"forcepacking\" value=\"unzip\"/>\n" : "") +
									(ForcePacking == ForcePacking.Zip ? "\t\t\t<flag name=\"forcepacking\" value=\"zip\"/>\n" : "") +
									(ForceMerging == ForceMerging.Full ? "\t\t\t<flag name=\"forcemerging\" value=\"full\"/>\n" : "") +
									(ForceMerging == ForceMerging.Split ? "\t\t\t<flag name=\"forcemerging\" value=\"split\"/>\n" : "") +
									(ForceMerging == ForceMerging.Merged ? "\t\t\t<flag name=\"forcemerging\" value=\"merged\"/>\n" : "") +
									(ForceMerging == ForceMerging.NonMerged ? "\t\t\t<flag name=\"forcemerging\" value=\"nonmerged\"/>\n" : "") +
									(ForceNodump == ForceNodump.Ignore ? "\t\t\t<flag name=\"forcenodump\" value=\"ignore\"/>\n" : "") +
									(ForceNodump == ForceNodump.Obsolete ? "\t\t\t<flag name=\"forcenodump\" value=\"obsolete\"/>\n" : "") +
									(ForceNodump == ForceNodump.Required ? "\t\t\t<flag name=\"forcenodump\" value=\"required\"/>\n" : "") +
									"\t\t</flags>\n"
							: "") +
							"\t</header>\n" +
							"\t<data>\n";

				// Write the header out
				sw.Write(header);
				sw.Flush();
			}
			catch (Exception ex)
			{
				Globals.Logger.Error(ex.ToString());
				return false;
			}

			return true;
		}

		/// <summary>
		/// Write out Game start using the supplied StreamWriter
		/// </summary>
		/// <param name="sw">StreamWriter to output to</param>
		/// <param name="rom">DatItem object to be output</param>
		/// <param name="newsplit">Split path representing the parent game (SabreDAT only)</param>
		/// <param name="lastgame">The name of the last game to be output</param>
		/// <param name="depth">Current depth to output file at (SabreDAT only)</param>
		/// <param name="last">Last known depth to cycle back from (SabreDAT only)</param>
		/// <returns>The new depth of the tag</returns>
		private int WriteStartGame(StreamWriter sw, DatItem rom, List<string> newsplit, string lastgame, int depth, int last)
		{
			try
			{
				// No game should start with a path separator
				if (rom.MachineName.StartsWith(Path.DirectorySeparatorChar.ToString()))
				{
					rom.MachineName = rom.MachineName.Substring(1);
				}

				string state = "";
				for (int i = (last == -1 ? 0 : last); i < newsplit.Count; i++)
				{
					for (int j = 0; j < depth - last + i - (lastgame == null ? 1 : 0); j++)
					{
						state += "\t";
					}
					state += "<directory name=\"" + HttpUtility.HtmlEncode(newsplit[i]) + "\" description=\"" +
					HttpUtility.HtmlEncode(newsplit[i]) + "\">\n";
				}
				depth = depth - (last == -1 ? 0 : last) + newsplit.Count;

				sw.Write(state);
				sw.Flush();
			}
			catch (Exception ex)
			{
				Globals.Logger.Error(ex.ToString());
				return depth;
			}

			return depth;
		}

		/// <summary>
		/// Write out Game start using the supplied StreamWriter
		/// </summary>
		/// <param name="sw">StreamWriter to output to</param>
		/// <param name="splitpath">Split path representing last kwown parent game (SabreDAT only)</param>
		/// <param name="newsplit">Split path representing the parent game (SabreDAT only)</param>
		/// <param name="depth">Current depth to output file at (SabreDAT only)</param>
		/// <param name="last">Last known depth to cycle back from (SabreDAT only)</param>
		/// <returns>The new depth of the tag</returns>
		private int WriteEndGame(StreamWriter sw, List<string> splitpath, List<string> newsplit, int depth, out int last)
		{
			last = 0;

			try
			{
				string state = "";
				if (splitpath != null)
				{
					for (int i = 0; i < newsplit.Count && i < splitpath.Count; i++)
					{
						// Always keep track of the last seen item
						last = i;

						// If we find a difference, break
						if (newsplit[i] != splitpath[i])
						{
							break;
						}
					}

					// Now that we have the last known position, take down all open folders
					for (int i = depth - 1; i > last + 1; i--)
					{
						// Print out the number of tabs and the end folder
						for (int j = 0; j < i; j++)
						{
							state += "\t";
						}
						state += "</directory>\n";
					}

					// Reset the current depth
					depth = 2 + last;
				}

				sw.Write(state);
				sw.Flush();
			}
			catch (Exception ex)
			{
				Globals.Logger.Error(ex.ToString());
				return depth;
			}

			return depth;
		}

		/// <summary>
		/// Write out DatItem using the supplied StreamWriter
		/// </summary>
		/// <param name="sw">StreamWriter to output to</param>
		/// <param name="rom">DatItem object to be output</param>
		/// <param name="depth">Current depth to output file at (SabreDAT only)</param>
		/// <param name="ignoreblanks">True if blank roms should be skipped on output, false otherwise (default)</param>
		/// <returns>True if the data was written, false on error</returns>
		private bool WriteDatItem(StreamWriter sw, DatItem rom, int depth, bool ignoreblanks = false)
		{
			// If we are in ignore blanks mode AND we have a blank (0-size) rom, skip
			if (ignoreblanks
				&& (rom.Type == ItemType.Rom
				&& (((Rom)rom).Size == 0 || ((Rom)rom).Size == -1)))
			{
				return true;
			}

			try
			{
				string state = "", prefix = "";

				// Pre-process the item name
				ProcessItemName(rom, true);

				for (int i = 0; i < depth; i++)
				{
					prefix += "\t";
				}
				state += prefix;

				switch (rom.Type)
				{
					case ItemType.Archive:
						state += "<file type=\"archive\" name=\"" + HttpUtility.HtmlEncode(rom.Name) + "\""
							+ "/>\n";
						break;
					case ItemType.BiosSet:
						state += "<file type=\"biosset\" name\"" + HttpUtility.HtmlEncode(rom.Name) + "\""
							+ (!String.IsNullOrWhiteSpace(((BiosSet)rom).Description) ? " description=\"" + HttpUtility.HtmlEncode(((BiosSet)rom).Description) + "\"" : "")
							+ (((BiosSet)rom).Default != null
								? ((BiosSet)rom).Default.ToString().ToLowerInvariant()
								: "")
							+ "/>\n";
						break;
					case ItemType.Disk:
						state += "<file type=\"disk\" name=\"" + HttpUtility.HtmlEncode(rom.Name) + "\""
							+ (!String.IsNullOrWhiteSpace(((Disk)rom).MD5) ? " md5=\"" + ((Disk)rom).MD5.ToLowerInvariant() + "\"" : "")
							+ (!String.IsNullOrWhiteSpace(((Disk)rom).SHA1) ? " sha1=\"" + ((Disk)rom).SHA1.ToLowerInvariant() + "\"" : "")
							+ (!String.IsNullOrWhiteSpace(((Disk)rom).SHA256) ? " sha256=\"" + ((Disk)rom).SHA256.ToLowerInvariant() + "\"" : "")
							+ (!String.IsNullOrWhiteSpace(((Disk)rom).SHA384) ? " sha384=\"" + ((Disk)rom).SHA384.ToLowerInvariant() + "\"" : "")
							+ (!String.IsNullOrWhiteSpace(((Disk)rom).SHA512) ? " sha512=\"" + ((Disk)rom).SHA512.ToLowerInvariant() + "\"" : "")
							+ (((Disk)rom).ItemStatus != ItemStatus.None ? prefix + "/>\n" + prefix + "\t<flags>\n" +
								prefix + "\t\t<flag name=\"status\" value=\"" + ((Disk)rom).ItemStatus.ToString().ToLowerInvariant() + "\"/>\n" +
								prefix + "\t</flags>\n" +
								prefix + "</file>\n" : "/>\n");
						break;
					case ItemType.Release:
						state += "<file type=\"release\" name\"" + HttpUtility.HtmlEncode(rom.Name) + "\""
							+ (!String.IsNullOrWhiteSpace(((Release)rom).Region) ? " region=\"" + HttpUtility.HtmlEncode(((Release)rom).Region) + "\"" : "")
							+ (!String.IsNullOrWhiteSpace(((Release)rom).Language) ? " language=\"" + HttpUtility.HtmlEncode(((Release)rom).Language) + "\"" : "")
							+ (!String.IsNullOrWhiteSpace(((Release)rom).Date) ? " date=\"" + HttpUtility.HtmlEncode(((Release)rom).Date) + "\"" : "")
							+ (((Release)rom).Default != null
								? ((Release)rom).Default.ToString().ToLowerInvariant()
								: "")
							+ "/>\n";
						break;
					case ItemType.Rom:
						state += "<file type=\"rom\" name=\"" + HttpUtility.HtmlEncode(rom.Name) + "\""
							+ (((Rom)rom).Size != -1 ? " size=\"" + ((Rom)rom).Size + "\"" : "")
							+ (!String.IsNullOrWhiteSpace(((Rom)rom).CRC) ? " crc=\"" + ((Rom)rom).CRC.ToLowerInvariant() + "\"" : "")
							+ (!String.IsNullOrWhiteSpace(((Rom)rom).MD5) ? " md5=\"" + ((Rom)rom).MD5.ToLowerInvariant() + "\"" : "")
							+ (!String.IsNullOrWhiteSpace(((Rom)rom).SHA1) ? " sha1=\"" + ((Rom)rom).SHA1.ToLowerInvariant() + "\"" : "")
							+ (!String.IsNullOrWhiteSpace(((Rom)rom).SHA256) ? " sha256=\"" + ((Rom)rom).SHA256.ToLowerInvariant() + "\"" : "")
							+ (!String.IsNullOrWhiteSpace(((Rom)rom).SHA384) ? " sha384=\"" + ((Rom)rom).SHA384.ToLowerInvariant() + "\"" : "")
							+ (!String.IsNullOrWhiteSpace(((Rom)rom).SHA512) ? " sha512=\"" + ((Rom)rom).SHA512.ToLowerInvariant() + "\"" : "")
							+ (!String.IsNullOrWhiteSpace(((Rom)rom).Date) ? " date=\"" + ((Rom)rom).Date + "\"" : "")
							+ (((Rom)rom).ItemStatus != ItemStatus.None ? prefix + "/>\n" + prefix + "\t<flags>\n" +
								prefix + "\t\t<flag name=\"status\" value=\"" + ((Rom)rom).ItemStatus.ToString().ToLowerInvariant() + "\"/>\n" +
								prefix + "\t</flags>\n" +
								prefix + "</file>\n" : "/>\n");
						break;
					case ItemType.Sample:
						state += "<file type=\"sample\" name=\"" + HttpUtility.HtmlEncode(rom.Name) + "\""
							+ "/>\n";
						break;
				}

				sw.Write(state);
				sw.Flush();
			}
			catch (Exception ex)
			{
				Globals.Logger.Error(ex.ToString());
				return false;
			}

			return true;
		}

		/// <summary>
		/// Write out DAT footer using the supplied StreamWriter
		/// </summary>
		/// <param name="sw">StreamWriter to output to</param>
		/// <param name="depth">Current depth to output file at (SabreDAT only)</param>
		/// <returns>True if the data was written, false on error</returns>
		private bool WriteFooter(StreamWriter sw, int depth)
		{
			try
			{
				string footer = "";
				for (int i = depth - 1; i >= 2; i--)
				{
					// Print out the number of tabs and the end folder
					for (int j = 0; j < i; j++)
					{
						footer += "\t";
					}
					footer += "</directory>\n";
				}
				footer += "\t</data>\n</datafile>\n";

				// Write the footer out
				sw.Write(footer);
				sw.Flush();
			}
			catch (Exception ex)
			{
				Globals.Logger.Error(ex.ToString());
				return false;
			}

			return true;
		}
	}
}