//	Spludlow Software
//	Copyright © Samuel P. Ludlow 2020 All Rights Reserved
//	Distributed under the terms of the GNU General Public License version 3
//	Distributed WITHOUT ANY WARRANTY; without implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE
//	https://www.spludlow.co.uk/LICENCE.TXT
//	The Spludlow logo is a registered trademark of Samuel P. Ludlow and may not be used without permission
//	v1.14

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

using System.IO;

namespace Spludlow.Io
{
	public class FileStore
	{
		//	Int64
		//	ROOT\1234\5678\9012\1234567890123456.dat
		//	ROOT\1234\5678\9012\1234567890123456

		//	ROOT\0000\0000\0000\000000000000FFFF.dat

		//	4 = 65,535  

		//	Int32
		//	ROOT\1234\12345678.dat

		//	ROOT\0000\0000FFFF.dat


		public static string TempName(string rootPath)
		{
			return TempName(rootPath, ".tmp");
		}

		public static string TempName(string rootPath, string extention)
		{
			string tempRoot = rootPath + @"\TEMP";
			
			if (Directory.Exists(tempRoot) == false)
				Directory.CreateDirectory(tempRoot);

			Guid guid = Guid.NewGuid();

			string tempName = tempRoot + @"\" + DateTime.Now.ToString("yyyy-MM-dd-HH-mm-ss-") + guid.ToString() + extention;

			return tempName;
		}

		public static string FilePath(Int32 id, string rootPath, string extension, bool write)
		{
			return MakePath((UInt32)id, rootPath, extension, write, '\\');
		}
		public static string FilePath(UInt32 id, string rootPath, string extension, bool write)
		{
			return MakePath(id, rootPath, extension, write, '\\');
		}

		public static string WebPath(Int32 id, string rootPath, string extension, bool write)
		{
			return MakePath((UInt32)id, rootPath, extension, write, '/');
		}
		public static string WebPath(UInt32 id, string rootPath, string extension, bool write)
		{
			return MakePath(id, rootPath, extension, write, '/');
		}

		public static string FilePath(Int64 id, string rootPath, string extension, bool write)
		{
			return MakePath((UInt64)id, rootPath, extension, write, '\\');
		}
		public static string FilePath(UInt64 id, string rootPath, string extension, bool write)
		{
			return MakePath(id, rootPath, extension, write, '\\');
		}

		public static string WebPath(Int64 id, string rootPath, string extension, bool write)
		{
			return MakePath((UInt64)id, rootPath, extension, write, '/');
		}
		public static string WebPath(UInt64 id, string rootPath, string extension, bool write)
		{
			return MakePath(id, rootPath, extension, write, '/');
		}

		public static string MakePath(UInt32 id, string rootPath, string extension, bool write, char delimeter)
		{
			StringBuilder path = new StringBuilder();
			path.Append(rootPath);

			if (path[path.Length - 1] != delimeter)
				path.Append(delimeter);

			string dir = ((id & 0xFFFF0000) >> 16).ToString("X04");
			path.Append(dir);

			if (write == true)
			{
				string dirPath = path.ToString();
				if (Directory.Exists(dirPath) == false)
					Directory.CreateDirectory(dirPath);
			}

			path.Append(delimeter);
			path.Append(id.ToString("X08"));

			return MakePath(path, extension, write);
		}

		public static string MakePath(UInt64 id, string rootPath, string extension, bool write, char delimeter)
		{
			StringBuilder path = new StringBuilder();
			path.Append(rootPath);

			string[] dirs = new string[]
			{
				((id & 0xFFFF000000000000) >> 48).ToString("X04"),
				((id & 0x0000FFFF00000000) >> 32).ToString("X04"),
				((id & 0x00000000FFFF0000) >> 16).ToString("X04"),
			};

			foreach (string dir in dirs)
			{
				if (path[path.Length - 1] != delimeter)
					path.Append(delimeter);

				path.Append(dir);

				if (write == true)
				{
					string dirPath = path.ToString();
					if (Directory.Exists(dirPath) == false)
						Directory.CreateDirectory(dirPath);
				}
			}

			path.Append(delimeter);
			path.Append(id.ToString("X016"));

			return MakePath(path, extension, write);
		}

		public static string MakePath(StringBuilder path, string extension, bool write)
		{
			if (extension == null && write == false)
			{
				string partPath = path.ToString();

				string[] filenames = Directory.GetFiles(Path.GetDirectoryName(partPath), Path.GetFileName(partPath) + "*");

				if (filenames.Length != 1)
					throw new ApplicationException("Did not find 1 file:\t" + filenames.Length + ", " + partPath);

				return filenames[0];
			}

			if (extension != null && extension.Length > 0)
				path.Append(extension);

			return path.ToString();
		}

		public static void CleanStore(uint[] currentIds, string rootPath, string extention)
		{
			int reportFreq = 1024;

			List<uint> currentIdList = new List<uint>(currentIds);
			currentIdList.Sort();

			uint lastId = currentIdList[currentIdList.Count - 1];

			uint deleteCount = 0;

			for (uint id = 0; id <= lastId; ++id)
			{
				if ((id % reportFreq) == 0)
					Spludlow.Log.Info("Clean Store; Progress " + id + "/" + lastId);

				if (currentIdList.Contains(id) == true)
					continue;

				string filename = FilePath(id, rootPath, extention, false);

				if (File.Exists(filename) == false)
					continue;

				File.Delete(filename);

				++deleteCount;
			}

			Spludlow.Log.Finish("Clean Store; Finished, delete count: " + deleteCount);
		}


	}
}