using System;
using System.Diagnostics;
using System.IO;
using System.Linq;
#pragma warning disable IDE0005
using System.Windows;
#pragma warning restore IDE0005

namespace Flow.Launcher.Plugin.SharedCommands
{
    /// <summary>
    /// Commands that are useful to run on files... and folders!
    /// </summary>
    public static class FilesFolders
    {
        private const string FileExplorerProgramName = "explorer";

        /// <summary>
        /// Copies the folder and all of its files and folders 
        /// including subfolders to the target location
        /// </summary>
        /// <param name="sourcePath"></param>
        /// <param name="targetPath"></param>
        /// <param name="messageBoxExShow"></param>
        public static void CopyAll(this string sourcePath, string targetPath, Func<string, MessageBoxResult> messageBoxExShow = null)
        {
            // Get the subdirectories for the specified directory.
            DirectoryInfo dir = new DirectoryInfo(sourcePath);

            if (!dir.Exists)
            {
                throw new DirectoryNotFoundException(
                    "Source directory does not exist or could not be found: "
                    + sourcePath);
            }

            try
            {
                DirectoryInfo[] dirs = dir.GetDirectories();
                // If the destination directory doesn't exist, create it.
                if (!Directory.Exists(targetPath))
                {
                    Directory.CreateDirectory(targetPath);
                }

                // Get the files in the directory and copy them to the new location.
                FileInfo[] files = dir.GetFiles();
                foreach (FileInfo file in files)
                {
                    string temppath = Path.Combine(targetPath, file.Name);
                    file.CopyTo(temppath, false);
                }

                // Recursively copy subdirectories by calling itself on each subdirectory until there are no more to copy
                foreach (DirectoryInfo subdir in dirs)
                {
                    string temppath = Path.Combine(targetPath, subdir.Name);
                    CopyAll(subdir.FullName, temppath, messageBoxExShow);
                }
            }
            catch (Exception)
            {
#if DEBUG
                throw;
#else
                messageBoxExShow ??= MessageBox.Show;
                messageBoxExShow(string.Format("Copying path {0} has failed, it will now be deleted for consistency", targetPath));
                RemoveFolderIfExists(targetPath, messageBoxExShow);
#endif
            }

        }

        /// <summary>
        /// Check if the files and directories are identical between <paramref name="fromPath"/> 
        /// and <paramref name="toPath"/>
        /// </summary>
        /// <param name="fromPath"></param>
        /// <param name="toPath"></param>
        /// <param name="messageBoxExShow"></param>
        /// <returns></returns>
        public static bool VerifyBothFolderFilesEqual(this string fromPath, string toPath, Func<string, MessageBoxResult> messageBoxExShow = null)
        {
            try
            {
                var fromDir = new DirectoryInfo(fromPath);
                var toDir = new DirectoryInfo(toPath);

                if (fromDir.GetFiles("*", SearchOption.AllDirectories).Length != toDir.GetFiles("*", SearchOption.AllDirectories).Length)
                    return false;

                if (fromDir.GetDirectories("*", SearchOption.AllDirectories).Length != toDir.GetDirectories("*", SearchOption.AllDirectories).Length)
                    return false;

                return true;
            }
            catch (Exception)
            {
#if DEBUG
                throw;
#else
                messageBoxExShow ??= MessageBox.Show;
                messageBoxExShow(string.Format("Unable to verify folders and files between {0} and {1}", fromPath, toPath));
                return false;
#endif
            }

        }

        /// <summary>
        /// Deletes a folder if it exists
        /// </summary>
        /// <param name="path"></param>
        /// <param name="messageBoxExShow"></param>
        public static void RemoveFolderIfExists(this string path, Func<string, MessageBoxResult> messageBoxExShow = null)
        {
            try
            {
                if (Directory.Exists(path))
                    Directory.Delete(path, true);
            }
            catch (Exception)
            {
#if DEBUG
                throw;
#else
                messageBoxExShow ??= MessageBox.Show;
                messageBoxExShow(string.Format("Not able to delete folder {0}, please go to the location and manually delete it", path));
#endif
            }
        }

        /// <summary>
        /// Attempts to delete a directory robustly with retry logic for locked files.
        /// This method tries to delete files individually with retries, then removes empty directories.
        /// Returns true if the directory was completely deleted, false if some files/folders remain.
        /// </summary>
        /// <param name="path">The directory path to delete</param>
        /// <param name="maxRetries">Maximum number of retry attempts for locked files (default: 3)</param>
        /// <param name="retryDelayMs">Delay in milliseconds between retries (default: 100ms)</param>
        /// <returns>True if directory was fully deleted, false if some items remain</returns>
        public static bool TryDeleteDirectoryRobust(string path, int maxRetries = 3, int retryDelayMs = 100)
        {
            if (!Directory.Exists(path))
                return true;

            bool fullyDeleted = true;

            try
            {
                // First, try to delete all files in the directory tree
                var files = Directory.GetFiles(path, "*", SearchOption.AllDirectories);
                foreach (var file in files)
                {
                    bool fileDeleted = false;
                    for (int attempt = 0; attempt <= maxRetries; attempt++)
                    {
                        try
                        {
                            // Remove read-only attribute if present
                            var fileInfo = new FileInfo(file);
                            if (fileInfo.Exists && fileInfo.IsReadOnly)
                            {
                                fileInfo.IsReadOnly = false;
                            }

                            File.Delete(file);
                            fileDeleted = true;
                            break;
                        }
                        catch (UnauthorizedAccessException)
                        {
                            // File is in use or access denied, wait and retry
                            if (attempt < maxRetries)
                            {
                                System.Threading.Thread.Sleep(retryDelayMs);
                            }
                        }
                        catch (IOException)
                        {
                            // File is in use, wait and retry
                            if (attempt < maxRetries)
                            {
                                System.Threading.Thread.Sleep(retryDelayMs);
                            }
                        }
                        catch
                        {
                            // Other exceptions, don't retry
                            break;
                        }
                    }

                    if (!fileDeleted)
                    {
                        fullyDeleted = false;
                    }
                }

                // Then, try to delete all empty directories (from deepest to shallowest)
                var directories = Directory.GetDirectories(path, "*", SearchOption.AllDirectories)
                    .OrderByDescending(d => d.Length) // Delete deeper directories first
                    .ToArray();

                foreach (var directory in directories)
                {
                    try
                    {
                        if (Directory.Exists(directory) && !Directory.EnumerateFileSystemEntries(directory).Any())
                        {
                            Directory.Delete(directory, false);
                        }
                    }
                    catch
                    {
                        // If we can't delete an empty directory, mark as not fully deleted
                        fullyDeleted = false;
                    }
                }

                // Finally, try to delete the root directory itself
                try
                {
                    if (Directory.Exists(path) && !Directory.EnumerateFileSystemEntries(path).Any())
                    {
                        Directory.Delete(path, false);
                    }
                    else if (Directory.Exists(path))
                    {
                        fullyDeleted = false;
                    }
                }
                catch
                {
                    fullyDeleted = false;
                }
            }
            catch
            {
                fullyDeleted = false;
            }

            return fullyDeleted;
        }

        /// <summary>
        /// Checks if a directory exists
        /// </summary>
        /// <param name="path"></param>
        /// <returns></returns>
        public static bool LocationExists(this string path)
        {
            return Directory.Exists(path);
        }

        /// <summary>
        /// Checks if a file exists
        /// </summary>
        /// <param name="filePath"></param>
        /// <returns></returns>
        public static bool FileExists(this string filePath)
        {
            return File.Exists(filePath);
        }

        /// <summary>
        /// Checks if a file or directory exists
        /// </summary>
        /// <param name="path"></param>
        /// <returns></returns>
        public static bool FileOrLocationExists(this string path)
        {
            return LocationExists(path) || FileExists(path);
        }

        /// <summary>
        /// Open a directory window (using the OS's default handler, usually explorer)
        /// </summary>
        /// <param name="fileOrFolderPath"></param>
        /// <param name="messageBoxExShow"></param>
        public static void OpenPath(string fileOrFolderPath, Func<string, MessageBoxResult> messageBoxExShow = null)
        {
            var psi = new ProcessStartInfo
            {
                FileName = FileExplorerProgramName,
                UseShellExecute = true,
                Arguments = '"' + fileOrFolderPath + '"'
            };
            try
            {
                if (LocationExists(fileOrFolderPath) || FileExists(fileOrFolderPath))
                    Process.Start(psi);
            }
            catch (Exception)
            {
#if DEBUG
                throw;
#else
                messageBoxExShow ??= MessageBox.Show;
                messageBoxExShow(string.Format("Unable to open the path {0}, please check if it exists", fileOrFolderPath));
#endif
            }
        }

        /// <summary>
        /// Open a file with associated application
        /// </summary>
        /// <param name="filePath">File path</param>
        /// <param name="workingDir">Working directory</param>
        /// <param name="asAdmin">Open as Administrator</param>
        /// <param name="messageBoxExShow"></param>
        public static void OpenFile(string filePath, string workingDir = "", bool asAdmin = false, Func<string, MessageBoxResult> messageBoxExShow = null)
        {
            var psi = new ProcessStartInfo
            {
                FileName = filePath,
                UseShellExecute = true,
                WorkingDirectory = workingDir,
                Verb = asAdmin ? "runas" : string.Empty
            };
            try
            {
                if (FileExists(filePath))
                    Process.Start(psi);
            }
            catch (Exception)
            {
#if DEBUG
                throw;
#else
                messageBoxExShow ??= MessageBox.Show;
                messageBoxExShow(string.Format("Unable to open the path {0}, please check if it exists", filePath));
#endif
            }
        }

        ///<summary>
        /// This checks whether a given string is a zip file path.
        /// By default does not check if the zip file actually exist on disk, can do so by
        /// setting checkFileExists = true.
        ///</summary>
        public static bool IsZipFilePath(string querySearchString, bool checkFileExists = false)
        {
            if (IsLocationPathString(querySearchString) && querySearchString.Split('.').Last() == "zip")
            {
                if (checkFileExists)
                    return FileExists(querySearchString);

                return true;
            }

            return false;
        }

        ///<summary>
        /// This checks whether a given string is a directory path or network location string. 
        /// It does not check if location actually exists.
        ///</summary>
        public static bool IsLocationPathString(this string querySearchString)
        {
            if (string.IsNullOrEmpty(querySearchString) || querySearchString.Length < 3)
                return false;

            // // shared folder location, and not \\\location\
            if (querySearchString.StartsWith(@"\\")
                && querySearchString[2] != '\\')
                return true;

            // c:\
            if (char.IsLetter(querySearchString[0])
                && querySearchString[1] == ':'
                && querySearchString[2] == '\\')
            {
                return querySearchString.Length == 3 || querySearchString[3] != '\\';
            }

            return false;
        }

        ///<summary>
        /// Gets the previous level directory from a path string.
        /// Checks that previous level directory exists and returns it 
        /// as a path string, or empty string if doesn't exist
        ///</summary>
        public static string GetPreviousExistingDirectory(Func<string, bool> locationExists, string path)
        {
            var index = path.LastIndexOf('\\');
            if (index > 0 && index < (path.Length - 1))
            {
                string previousDirectoryPath = path[..(index + 1)];
                return locationExists(previousDirectoryPath) ? previousDirectoryPath : string.Empty;
            }
            else
            {
                return string.Empty;
            }
        }

        ///<summary>
        /// Returns the previous level directory if path incomplete (does not end with '\').
        /// Does not check if previous level directory exists.
        /// Returns passed in string if is complete path
        ///</summary>
        public static string ReturnPreviousDirectoryIfIncompleteString(string path)
        {
            if (!path.EndsWith("\\"))
            {
                // not full path, get previous level directory string
                var indexOfSeparator = path.LastIndexOf('\\');

                return path[..(indexOfSeparator + 1)];
            }

            return path;
        }

        /// <summary>
        /// Returns if <paramref name="parentPath"/> contains <paramref name="subPath"/>. Equal paths are not considered to be contained by default.
        /// From https://stackoverflow.com/a/66877016
        /// </summary>
        /// <param name="parentPath">Parent path</param>
        /// <param name="subPath">Sub path</param>
        /// <param name="allowEqual">If <see langword="true"/>, when <paramref name="parentPath"/> and <paramref name="subPath"/> are equal, returns <see langword="true"/></param>
        /// <returns></returns>
        public static bool PathContains(string parentPath, string subPath, bool allowEqual = false)
        {
            var rel = Path.GetRelativePath(parentPath.EnsureTrailingSlash(), subPath);
            return (rel != "." || allowEqual)
                   && rel != ".."
                   && !rel.StartsWith("../")
                   && !rel.StartsWith(@"..\")
                   && !Path.IsPathRooted(rel);
        }
        
        /// <summary>
        /// Returns path ended with "\"
        /// </summary>
        /// <param name="path"></param>
        /// <returns></returns>
        public static string EnsureTrailingSlash(this string path)
        {
            return path.TrimEnd(Path.DirectorySeparatorChar) + Path.DirectorySeparatorChar;
        }

        /// <summary>
        /// Validates a directory, creating it if it doesn't exist
        /// </summary>
        /// <param name="path"></param>
        public static void ValidateDirectory(string path)
        {
            if (!Directory.Exists(path))
            {
                Directory.CreateDirectory(path);
            }
        }

        /// <summary>
        /// Validates a data directory, synchronizing it by ensuring all files from a bundled source directory exist in it.
        /// If files are missing or outdated, they are copied from the bundled directory to the data directory.
        /// </summary>
        /// <param name="bundledDataDirectory"></param>
        /// <param name="dataDirectory"></param>
        public static void ValidateDataDirectory(string bundledDataDirectory, string dataDirectory)
        {
            if (!Directory.Exists(dataDirectory))
            {
                Directory.CreateDirectory(dataDirectory);
            }

            foreach (var bundledDataPath in Directory.GetFiles(bundledDataDirectory))
            {
                var data = Path.GetFileName(bundledDataPath);
                if (data == null) continue;
                var dataPath = Path.Combine(dataDirectory, data);
                if (!File.Exists(dataPath))
                {
                    File.Copy(bundledDataPath, dataPath);
                }
                else
                {
                    var time1 = new FileInfo(bundledDataPath).LastWriteTimeUtc;
                    var time2 = new FileInfo(dataPath).LastWriteTimeUtc;
                    if (time1 != time2)
                    {
                        File.Copy(bundledDataPath, dataPath, true);
                    }
                }
            }
        }
    }
}