using Apewer;
using System;
using System.Collections.Generic;
using System.Text;

namespace Apewer.Internals
{

    internal class StorageHelper
    {

        public static bool FileExists(string argPath)
        {
            if (string.IsNullOrEmpty(argPath)) return false;
            return System.IO.File.Exists(argPath);
        }

        public static bool DirectoryExists(string argPath)
        {
            if (string.IsNullOrEmpty(argPath)) return false;
            return System.IO.Directory.Exists(argPath);
        }

        public static bool PathExists(string argPath)
        {
            if (string.IsNullOrEmpty(argPath)) return false;
            if (System.IO.File.Exists(argPath)) return true;
            if (System.IO.Directory.Exists(argPath)) return true;
            return false;
        }

        /// <summary>获取指定目录下子文件的路径,不递归子目录。</summary>
        /// <param name="argDirectory">顶级目录。</param>
        public static List<string> GetSubFiles(string argDirectory)
        {
            return GetSubFiles(argDirectory, false, false);
        }

        /// <summary>获取指定目录下子文件的路径。</summary>
        /// <param name="argDirectory">顶级目录。</param>
        /// <param name="argRecurSub">递归子目录。</param>
        /// <param name="argRecurPrecedence">优先排列递归项。</param>
        public static List<string> GetSubFiles(string argDirectory, bool argRecurSub, bool argRecurPrecedence)
        {
            return GetSubFiles(argDirectory, argRecurSub ? -1 : 0, argRecurPrecedence);
        }

        /// <summary>获取指定目录下子文件的路径。</summary>
        /// <param name="argDirectory">顶级目录。</param>
        /// <param name="argRecurDepth">子目录递归深度。</param>
        /// <param name="argRecurPrecedence">优先排列递归项。</param>
        public static List<string> GetSubFiles(string argDirectory, int argRecurDepth, bool argRecurPrecedence)
        {
            var list = new List<string>();
            if (string.IsNullOrEmpty(argDirectory)) return list;

            var directorylist = new List<string>();
            if (argRecurDepth == 0)
            {
                directorylist.Add(argDirectory);
            }
            else
            {
                var recurdicrotylist = GetSubDirectories(argDirectory, argRecurDepth, argRecurPrecedence);
                if (argRecurPrecedence)
                {
                    directorylist.AddRange(recurdicrotylist);
                    directorylist.Add(argDirectory);
                }
                else
                {
                    directorylist.Add(argDirectory);
                    directorylist.AddRange(recurdicrotylist);
                }
            }

            foreach (var directory in directorylist)
            {
                try
                {
                    var files = System.IO.Directory.GetFiles(directory);
                    list.AddRange(files);
                }
                catch { }
            }

            return list;
        }

        /// <summary>获取指定目录下子目录的路径。</summary>
        /// <param name="argDirectory">顶级目录。</param>
        /// <param name="argRecurSub">递归子目录。</param>
        /// <param name="argRecurPrecedence">优先排列递归项。</param>
        public static List<string> GetSubDirectories(string argDirectory, bool argRecurSub, bool argRecurPrecedence)
        {
            return GetSubDirectories(argDirectory, argRecurSub ? -1 : 0, argRecurPrecedence);
        }

        /// <summary>获取指定目录下子目录的路径。</summary>
        /// <param name="argDirectory">顶级目录。</param>
        /// <param name="argRecurDepth">子目录递归深度。</param>
        /// <param name="argRecurPrecedence">优先排列递归项。</param>
        public static List<string> GetSubDirectories(string argDirectory, int argRecurDepth, bool argRecurPrecedence)
        {
            var list = new List<string>();
            if (string.IsNullOrEmpty(argDirectory)) return list;

            var directories = new string[0];

            try
            {
                directories = System.IO.Directory.GetDirectories(argDirectory);
            }
            catch { }

            foreach (var directory in directories)
            {
                var recurlist = new List<string>();
                if (argRecurDepth != 0)
                {
                    var depth = (argRecurDepth > 0) ? argRecurDepth - 1 : argRecurDepth;
                    var subrecur = GetSubDirectories(directory, depth, argRecurPrecedence);
                    recurlist.AddRange(subrecur);
                }

                if (argRecurPrecedence)
                {
                    list.AddRange(recurlist);
                    list.Add(directory);
                }
                else
                {
                    list.Add(directory);
                    list.AddRange(recurlist);
                }
            }

            return list;
        }

        public static bool DeleteFile(string argPath)
        {
            if (string.IsNullOrEmpty(argPath)) return false;
            if (!PathExists(argPath)) return true;
            try
            {
                if (FileExists(argPath)) System.IO.File.Delete(argPath);
                return !PathExists(argPath);
            }
            catch { return false; }
        }

        public static bool DeleteDirectory(string argPath, bool argRecursive = true)
        {
            if (string.IsNullOrEmpty(argPath)) return false;
            if (!PathExists(argPath)) return true;
            try
            {
                if (DirectoryExists(argPath)) System.IO.Directory.Delete(argPath, argRecursive);
                return !PathExists(argPath);
            }
            catch { return false; }
        }

        public static bool DeletePath(string argPath, bool argRecursive = true)
        {
            if (string.IsNullOrEmpty(argPath)) return false;
            if (!PathExists(argPath)) return true;
            try
            {
                if (FileExists(argPath)) System.IO.File.Delete(argPath);
                if (DirectoryExists(argPath)) System.IO.Directory.Delete(argPath, argRecursive);
                return !PathExists(argPath);
            }
            catch { return false; }
        }

        public static bool AssureDirectory(string argPath)
        {
            if (string.IsNullOrEmpty(argPath)) return false;
            try
            {
                if (System.IO.File.Exists(argPath)) return false;
                if (System.IO.Directory.Exists(argPath)) return true;
                var created = System.IO.Directory.CreateDirectory(argPath);
                return created.Exists;
            }
            catch { }
            return false;
        }

        public static bool AssureParent(string argFilePath)
        {
            if (string.IsNullOrEmpty(argFilePath)) return false;
            var parent = Constant.EmptyString;
            try { parent = System.IO.Directory.GetParent(argFilePath).FullName; } finally { }
            var result = AssureDirectory(parent);
            return result;
        }

        /// <summary>获取文件流。若文件不存在,则先创建文件;若获取失败,则返回 NULL 值。</summary>
        /// <param name="argPath">文件路径。</param>
        /// <param name="argShare">共享。</param>
        public static System.IO.FileStream OpenFile(string argPath, bool argShare = false)
        {
            try
            {
                if (string.IsNullOrEmpty(argPath)) return null;
                if (DirectoryExists(argPath)) return null;

                if (AssureParent(argPath))
                {
                    var mode = System.IO.FileMode.OpenOrCreate;
                    var access = System.IO.FileAccess.ReadWrite;
                    var share = argShare ? System.IO.FileShare.ReadWrite : System.IO.FileShare.None;
                    var stream = new System.IO.FileStream(argPath, mode, access, share);
                    return stream;
                }
            }
            catch { }
            return null;
        }

        /// <summary>创建一个空文件且不保留句柄。</summary>
        /// <param name="argPath">文件路径,若已存在则返回失败。</param>
        /// <param name="argLength">文件长度(字节数)。</param>
        /// <param name="argReplace">替换现有文件。</param>
        /// <returns>创建成功。</returns>
        public static bool CreateFile(string argPath, long argLength = 0, bool argReplace = false)
        {
            try
            {
                if (string.IsNullOrEmpty(argPath)) return false;
                if (argReplace) { if (!DeletePath(argPath, true)) return false; }
                else { if (PathExists(argPath)) return false; }

                var stream = OpenFile(argPath);
                if (stream != null)
                {
                    if (argLength > 0)
                    {
                        stream.SetLength(argLength);
                    }
                    stream.Close();
                    stream.Dispose();
                    return true;
                }
            }
            catch { }
            return false;
        }

        /// <summary>向文件写入数据。若写入失败则返回 -1 值。</summary>
        public static long WriteFile(string argPath, System.IO.Stream argStream, Action<Int64> argCallback = null)
        {
            var created = CreateFile(argPath, 0, true);
            if (created)
            {
                var stream = OpenFile(argPath);
                var result = 0L;
                if (stream != null)
                {
                    result = StreamHelper.Read(argStream, stream, Constant.DefaultBufferCapacity, argCallback);
                }
                KernelUtility.Dispose(stream);
                return result;
            }
            return -1;
        }

        /// <summary>向文件写入数据。文件不存在将创建,存在则覆盖。</summary>
        public static bool WriteFile(string argPath, byte[] argData)
        {
            return WriteFile(argPath, false, argData);
        }

        /// <summary>向文件写入数据。文件不存在将创建,存在则覆盖。</summary>
        public static bool WriteFile(string argPath, bool argAddBom, byte[] argData)
        {
            var created = CreateFile(argPath, 0, true);
            if (created)
            {
                try
                {
                    if (argData == null) return true;
                    var data = argData;
                    if (argAddBom) data = ByteHelper.AddTextBom(data);
                    System.IO.File.WriteAllBytes(argPath, data);
                    return true;
                }
                finally { }
            }
            return false;
        }

        /// <summary>向文件写入数据。若写入失败则返回 -1 值。</summary>
        public static long AppendFile(string argPath, System.IO.Stream argStream, Action<Int64> argCallback = null)
        {
            var error = -1;
            var assured = AssureParent(argPath);
            if (assured)
            {
                var stream = OpenFile(argPath, true);
                var result = 0L;
                if (stream != null)
                {
                    var failed = false;
                    try { stream.Position = stream.Length; } catch { failed = true; }
                    if (!failed)
                    {
                        result = StreamHelper.Read(argStream, stream, Constant.DefaultBufferCapacity, argCallback);
                    }
                    try { stream.Flush(); } finally { }
                }
                KernelUtility.Dispose(stream);
                return result;
            }
            return error;
        }

        /// <summary>向文件追加数据。文件不存在将创建,存在则覆盖。</summary>
        public static bool AppendFile(string argPath, params byte[] argData)
        {
            var assured = AssureParent(argPath);
            if (assured)
            {
                var stream = OpenFile(argPath, true);
                var failed = false;
                if (stream != null)
                {
                    try
                    {
                        stream.Position = stream.Length;
                        if (argData != null) stream.Write(argData, 0, argData.Length);
                    }
                    catch { failed = true; }
                    KernelUtility.Dispose(stream, true);
                }
                if (!failed) return true;
            }
            return false;
        }

        /// <summary>复制文件。</summary>
        /// <param name="argOldPath">旧路径。</param>
        /// <param name="argNewPath">新路径。</param>
        /// <param name="argReplace">新路劲存在时,替换新文件。</param>
        public static bool CopyFile(string argOldPath, string argNewPath, bool argReplace = true)
        {
            if (string.IsNullOrEmpty(argOldPath)) return false;
            if (string.IsNullOrEmpty(argNewPath)) return false;
            if (!FileExists(argOldPath)) return false;
            try
            {
                System.IO.File.Copy(argOldPath, argNewPath, argReplace);
                return true;
            }
            catch { return false; }
        }

        public static byte[] ReadFile(string argFilePath, bool argWipeBom = true, Action<Int64> argCallback = null)
        {
            if (FileExists(argFilePath))
            {
                var bytes = null as byte[];

                if (argCallback == null)
                {
                    try
                    {
                        bytes = System.IO.File.ReadAllBytes(argFilePath);
                    }
                    catch { }
                }
                else
                {
                    var file = null as System.IO.FileStream;
                    var memory = new System.IO.MemoryStream();
                    file = OpenFile(argFilePath, true);
                    StreamHelper.Read(file, memory, Constant.DefaultBufferCapacity, argCallback);
                    if (file != null) file.Dispose();
                    bytes = memory.ToArray();
                    memory.Dispose();
                }

                if (argWipeBom) bytes = ByteHelper.WipeTextBom(bytes);
                return bytes;
            }
            return Constant.EmptyBytes;
        }

        public static string FixFileName(string argFileName)
        {
            var result = argFileName;
            if (string.IsNullOrEmpty(result))
            {
                result = Constant.EmptyString;
            }
            else
            {
                result = result.Replace("\"", "");
                result = result.Replace("\\", "");
                result = result.Replace("/", "");
                result = result.Replace(":", "");
                result = result.Replace("*", "");
                result = result.Replace("?", "");
                result = result.Replace("<", "");
                result = result.Replace(">", "");
                result = result.Replace("|", "");
            }
            if (result.Length > 0) result = result.Trim();
            return result;
        }

    }

}