using MediaBrowser.Model.Logging;
using System;
using System.Collections.Specialized;
using System.IO;
using System.Text;

namespace MediaBrowser.Controller.IO
{
    /// <summary>
    /// Class FileSystem
    /// </summary>
    public static class FileSystem
    {
        /// <summary>
        /// Gets the file system info.
        /// </summary>
        /// <param name="path">The path.</param>
        /// <returns>FileSystemInfo.</returns>
        public static FileSystemInfo GetFileSystemInfo(string path)
        {
            // Take a guess to try and avoid two file system hits, but we'll double-check by calling Exists
            if (Path.HasExtension(path))
            {
                var fileInfo = new FileInfo(path);

                if (fileInfo.Exists)
                {
                    return fileInfo;
                }

                return new DirectoryInfo(path);
            }
            else
            {
                var fileInfo = new DirectoryInfo(path);

                if (fileInfo.Exists)
                {
                    return fileInfo;
                }

                return new FileInfo(path);
            }
        }

        /// <summary>
        /// Gets the creation time UTC.
        /// </summary>
        /// <param name="info">The info.</param>
        /// <param name="logger">The logger.</param>
        /// <returns>DateTime.</returns>
        public static DateTime GetLastWriteTimeUtc(FileSystemInfo info, ILogger logger)
        {
            // This could throw an error on some file systems that have dates out of range

            try
            {
                return info.LastAccessTimeUtc;
            }
            catch (Exception ex)
            {
                logger.ErrorException("Error determining LastAccessTimeUtc for {0}", ex, info.FullName);
                return DateTime.MinValue;
            }
        }

        /// <summary>
        /// Gets the creation time UTC.
        /// </summary>
        /// <param name="info">The info.</param>
        /// <param name="logger">The logger.</param>
        /// <returns>DateTime.</returns>
        public static DateTime GetCreationTimeUtc(FileSystemInfo info, ILogger logger)
        {
            // This could throw an error on some file systems that have dates out of range

            try
            {
                return info.CreationTimeUtc;
            }
            catch (Exception ex)
            {
                logger.ErrorException("Error determining CreationTimeUtc for {0}", ex, info.FullName);
                return DateTime.MinValue;
            }
        }

        /// <summary>
        /// The space char
        /// </summary>
        private const char SpaceChar = ' ';
        /// <summary>
        /// The invalid file name chars
        /// </summary>
        private static readonly char[] InvalidFileNameChars = Path.GetInvalidFileNameChars();

        /// <summary>
        /// Takes a filename and removes invalid characters
        /// </summary>
        /// <param name="filename">The filename.</param>
        /// <returns>System.String.</returns>
        /// <exception cref="System.ArgumentNullException">filename</exception>
        public static string GetValidFilename(string filename)
        {
            if (string.IsNullOrEmpty(filename))
            {
                throw new ArgumentNullException("filename");
            }
            
            foreach (var c in InvalidFileNameChars)
            {
                filename = filename.Replace(c, SpaceChar);
            }

            return filename;
        }

        /// <summary>
        /// Resolves the shortcut.
        /// </summary>
        /// <param name="filename">The filename.</param>
        /// <returns>System.String.</returns>
        /// <exception cref="System.ArgumentNullException">filename</exception>
        public static string ResolveShortcut(string filename)
        {
            if (string.IsNullOrEmpty(filename))
            {
                throw new ArgumentNullException("filename");
            }
            
            var link = new ShellLink();
            ((IPersistFile)link).Load(filename, NativeMethods.STGM_READ);
            // TODO: if I can get hold of the hwnd call resolve first. This handles moved and renamed files.  
            // ((IShellLinkW)link).Resolve(hwnd, 0) 
            var sb = new StringBuilder(NativeMethods.MAX_PATH);
            WIN32_FIND_DATA data;
            ((IShellLinkW)link).GetPath(sb, sb.Capacity, out data, 0);
            return sb.ToString();
        }

        /// <summary>
        /// Creates a shortcut file pointing to a specified path
        /// </summary>
        /// <param name="shortcutPath">The shortcut path.</param>
        /// <param name="target">The target.</param>
        /// <exception cref="System.ArgumentNullException">shortcutPath</exception>
        public static void CreateShortcut(string shortcutPath, string target)
        {
            if (string.IsNullOrEmpty(shortcutPath))
            {
                throw new ArgumentNullException("shortcutPath");
            }

            if (string.IsNullOrEmpty(target))
            {
                throw new ArgumentNullException("target");
            }
            
            var link = new ShellLink();

            ((IShellLinkW)link).SetPath(target);

            ((IPersistFile)link).Save(shortcutPath, true);
        }

        /// <summary>
        /// Determines whether the specified filename is shortcut.
        /// </summary>
        /// <param name="filename">The filename.</param>
        /// <returns><c>true</c> if the specified filename is shortcut; otherwise, <c>false</c>.</returns>
        /// <exception cref="System.ArgumentNullException">filename</exception>
        public static bool IsShortcut(string filename)
        {
            if (string.IsNullOrEmpty(filename))
            {
                throw new ArgumentNullException("filename");
            }
            
            return string.Equals(Path.GetExtension(filename), ".lnk", StringComparison.OrdinalIgnoreCase);
        }

        /// <summary>
        /// Copies all.
        /// </summary>
        /// <param name="source">The source.</param>
        /// <param name="target">The target.</param>
        /// <exception cref="System.ArgumentNullException">source</exception>
        /// <exception cref="System.ArgumentException">The source and target directories are the same</exception>
        public static void CopyAll(string source, string target)
        {
            if (string.IsNullOrEmpty(source))
            {
                throw new ArgumentNullException("source");
            }
            if (string.IsNullOrEmpty(target))
            {
                throw new ArgumentNullException("target");
            }

            if (source.Equals(target, StringComparison.OrdinalIgnoreCase))
            {
                throw new ArgumentException("The source and target directories are the same");
            }

            // Check if the target directory exists, if not, create it. 
            if (!Directory.Exists(target))
            {
                Directory.CreateDirectory(target);
            }

            foreach (var file in Directory.EnumerateFiles(source))
            {
                File.Copy(file, Path.Combine(target, Path.GetFileName(file)), true);
            }

            // Copy each subdirectory using recursion. 
            foreach (var dir in Directory.EnumerateDirectories(source))
            {
                CopyAll(dir, Path.Combine(target, Path.GetFileName(dir)));
            }
        }

        /// <summary>
        /// Parses the ini file.
        /// </summary>
        /// <param name="path">The path.</param>
        /// <returns>NameValueCollection.</returns>
        public static NameValueCollection ParseIniFile(string path)
        {
            var values = new NameValueCollection();

            foreach (var line in File.ReadAllLines(path))
            {
                var data = line.Split('=');

                if (data.Length < 2) continue;

                var key = data[0];

                var value = data.Length == 2 ? data[1] : string.Join(string.Empty, data, 1, data.Length - 1);

                values[key] = value;
            }

            return values;
        }
    }
}