// Copyright (c) Microsoft Corporation
// The Microsoft Corporation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
using System;
using System.Collections.Concurrent;
using System.IO;

using Wox.Plugin.Common.Interfaces;
using Wox.Plugin.Common.Win32;

namespace Wox.Plugin.Common
{
    /// <summary>
    /// Class to get localized name of shell items like 'My computer'. The localization is based on the 'windows display language'.
    /// </summary>
    public class ShellLocalization
    {
        // Cache for already localized names. This makes localization of already localized string faster.
        private ConcurrentDictionary<string, string> _localizationCache = new ConcurrentDictionary<string, string>();

        /// <summary>
        /// Returns the localized name of a shell item.
        /// </summary>
        /// <param name="path">Path to the shell item (e. g. shortcut 'File Explorer.lnk').</param>
        /// <returns>The localized name as string or <see cref="string.Empty"/>.</returns>
        public string GetLocalizedName(string path)
        {
            string lowerInvariantPath = path.ToLowerInvariant();

            // Checking cache if path is already localized
            if (_localizationCache.TryGetValue(lowerInvariantPath, out string value))
            {
                return value;
            }

            Guid shellItemType = ShellItemTypeConstants.ShellItemGuid;
            int retCode = NativeMethods.SHCreateItemFromParsingName(path, IntPtr.Zero, ref shellItemType, out IShellItem shellItem);
            if (retCode != 0)
            {
                return string.Empty;
            }

            shellItem.GetDisplayName(SIGDN.NORMALDISPLAY, out string filename);

            _ = _localizationCache.TryAdd(lowerInvariantPath, filename);

            return filename;
        }

        /// <summary>
        /// This method returns the localized path to a shell item (folder or file)
        /// </summary>
        /// <param name="path">The path to localize</param>
        /// <returns>The localized path or the original path if localized version is not available</returns>
        public string GetLocalizedPath(string path)
        {
            path = Environment.ExpandEnvironmentVariables(path);
            string ext = Path.GetExtension(path);
            var pathParts = path.Split("\\");
            string[] locPath = new string[pathParts.Length];

            for (int i = 0; i < pathParts.Length; i++)
            {
                if (i == 0 && pathParts[i].EndsWith(':'))
                {
                    // Skip the drive letter.
                    locPath[0] = pathParts[0];
                    continue;
                }

                // Localize path.
                int iElements = i + 1;
                string lName = GetLocalizedName(string.Join("\\", pathParts[..iElements]));
                locPath[i] = !string.IsNullOrEmpty(lName) ? lName : pathParts[i];
            }

            string newPath = string.Join("\\", locPath);
            newPath = !newPath.EndsWith(ext, StringComparison.InvariantCultureIgnoreCase) ? newPath + ext : newPath;

            return newPath;
        }
    }
}
