/*
Copyright (c) 2022, John Lewin, Lars Brubaker
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice, this
   list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
   this list of conditions and the following disclaimer in the documentation
   and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

The views and conclusions contained in the software and documentation are those
of the authors and should not be interpreted as representing official policies,
either expressed or implied, of the FreeBSD Project.
*/

using System;
using System.Collections.Generic;
using System.IO;
using System.IO.Compression;
using System.Linq;
using System.Threading.Tasks;
using MatterHackers.Agg;
using MatterHackers.Agg.Image;
using MatterHackers.Agg.Platform;
using MatterHackers.Agg.UI;
using MatterHackers.DataConverters3D;
using MatterHackers.Localizations;
using MatterHackers.MatterControl.DataStorage;

namespace MatterHackers.MatterControl.Library
{
    public class FileSystemContainer : WritableContainer, ICustomSearch
    {
        private FileSystemWatcher directoryWatcher;

        private bool isActiveContainer;
        private bool isDirty;
        private string keywordFilter;

        private long lastTimeContentsChanged;

        private RunningInterval waitingForRefresh;

        public FileSystemContainer(string fullPath)
        {
            this.CustomSearch = this;
            this.FullPath = fullPath;
            this.Name = Path.GetFileName(fullPath);

            this.IsProtected = false;

            this.ChildContainers = new SafeList<ILibraryContainerLink>();
            this.Items = new SafeList<ILibraryItem>();

            if (AggContext.OperatingSystem == OSType.Windows
                && Directory.Exists(fullPath))
            {
                directoryWatcher = new FileSystemWatcher(fullPath);
                directoryWatcher.NotifyFilter = NotifyFilters.LastWrite | NotifyFilters.FileName | NotifyFilters.DirectoryName;
                directoryWatcher.Changed += DirectoryContentsChanged;
                directoryWatcher.Created += DirectoryContentsChanged;
                directoryWatcher.Deleted += DirectoryContentsChanged;
                directoryWatcher.Renamed += DirectoryContentsChanged;
                directoryWatcher.IncludeSubdirectories = false;

                // Begin watching.
                directoryWatcher.EnableRaisingEvents = true;
            }
        }

        public override async Task Save(ILibraryItem item, IObject3D content)
        {
            if (item is FileSystemFileItem fileItem)
            {
                if (fileItem.FilePath.Contains(ApplicationDataStorage.Instance.ApplicationLibraryDataPath))
                {
                    // save using the normal uncompressed mcx file
                    // Serialize the scene to disk using a modified Json.net pipeline with custom ContractResolvers and JsonConverters
                    File.WriteAllText(fileItem.FilePath, content.ToJson().Result);

                    this.OnItemContentChanged(new LibraryItemChangedEventArgs(fileItem));
                }
                else
                {
                    await ApplicationController.Instance.Tasks.Execute(
                        "Saving Changes".Localize(),
                        null,
                        async (reporter, cancellationTokenSource) =>
                        {
                            var directory = Path.GetDirectoryName(fileItem.FilePath);
                            var filename = Path.GetFileNameWithoutExtension(fileItem.FilePath);
                            var backupName = Path.Combine(directory, Path.ChangeExtension(filename + "_bak", ".mcx"));

                            try
                            {
                                if (File.Exists(backupName))
                                {
                                    File.Delete(backupName);
                                }

                                // rename any existing file
                                if (File.Exists(fileItem.FilePath))
                                {
                                    File.Move(fileItem.FilePath, backupName);
                                }
                            }
                            catch
                            {
                            }

                            // make sure we have all the mesh items in the cache for saving to the archive
                            await content.PersistAssets((percentComplete, text) =>
                            {
                                reporter?.Invoke(percentComplete * .9, null);
                            }, true);

                            var persistableItems = content.GetPersistable(true);
                            var persistCount = persistableItems.Count();
                            var savedCount = 0;

                            // save to a binary mcx file (a zip with a scene.mcx and an assets folder)
                            using (var file = File.OpenWrite(fileItem.FilePath))
                            {
                                using (var zip = new ZipArchive(file, ZipArchiveMode.Create))
                                {
                                    var savedItems = new HashSet<string>();
                                    foreach (var persistableItem in persistableItems)
                                    {
                                        string sourcePath = null;
                                        if (persistableItem.MeshPath != null)
                                        {
                                            sourcePath = Path.Combine(ApplicationDataStorage.Instance.LibraryAssetsPath, Path.GetFileName(persistableItem.MeshPath));
                                        }

                                        if (persistableItem is AssetObject3D assetObject3D)
                                        {
                                            sourcePath = Path.Combine(ApplicationDataStorage.Instance.LibraryAssetsPath, Path.GetFileName(assetObject3D.AssetPath));
                                        }

                                        var destFilename = Path.GetFileName(sourcePath);
                                        if (File.Exists(sourcePath))
                                        {
                                            if (!savedItems.Contains(destFilename))
                                            {
                                                savedItems.Add(destFilename);
                                                var assetName = Path.Combine("Assets", destFilename);
                                                zip.CreateEntryFromFile(sourcePath, assetName);
                                            }
                                        }
                                        else
                                        {
                                            int a = 0;
                                        }

                                        savedCount++;
                                        reporter?.Invoke(.9 + .1 * (savedCount / persistCount), null);
                                    }

                                    var sceneEntry = zip.CreateEntry("scene.mcx");
                                    using (var sceneStream = sceneEntry.Open())
                                    {
                                        using (var writer = new StreamWriter(sceneStream))
                                        {
                                            writer.Write(await content.ToJson());
                                        }
                                    }
                                }
                            }

                            // Serialize the scene to disk using a modified Json.net pipeline with custom ContractResolvers and JsonConverters
                            this.OnItemContentChanged(new LibraryItemChangedEventArgs(fileItem));

                            // remove the existing file after a successfull save
                            try
                            {
                                if (File.Exists(backupName))
                                {
                                    File.Delete(backupName);
                                }
                            }
                            catch { }
                        });
                }
            }
        }

        public override void SetThumbnail(ILibraryItem item, int width, int height, ImageBuffer imageBuffer)
        {
#if DEBUG
            // throw new NotImplementedException();
#endif
        }

        public override ICustomSearch CustomSearch { get; }

        public string FullPath { get; protected set; }

        // Indicates if the new AMF file should use the original file name incremented until no name collision occurs
        public bool UseIncrementedNameDuringTypeChange { get; internal set; }

        public override void Activate()
        {
            this.isActiveContainer = true;
            base.Activate();
        }

        public async override void Add(IEnumerable<ILibraryItem> items)
        {
            if (!items.Any())
            {
                return;
            }

            if (directoryWatcher != null)
            {
                // turn them off whil ewe add the content
                directoryWatcher.EnableRaisingEvents = false;
            }

            Directory.CreateDirectory(this.FullPath);

            await Task.Run(async () =>
            {
                foreach (var item in items)
                {
                    switch (item)
                    {
                        case CreateFolderItem newFolder:
                            string targetFolderPath = Path.Combine(this.FullPath, newFolder.Name);

                            // TODO: write adaption of GetNonCollidingName for directories
                            Directory.CreateDirectory(targetFolderPath);
                            this.isDirty = true;

                            break;

                        case ILibraryAssetStream streamItem:
                            string targetPath = Path.Combine(this.FullPath, streamItem.FileName);

                            try
                            {
                                if (File.Exists(targetPath))
                                {
                                    targetPath = GetNonCollidingName(Path.GetFileName(targetPath));
                                }

                                using (var outputStream = File.OpenWrite(targetPath))
                                using (var contentStream = await streamItem.GetStream(null))
                                {
                                    contentStream.Stream.CopyTo(outputStream);
                                }

                                this.Items.Add(new FileSystemFileItem(targetPath));
                                this.isDirty = true;
                            }
                            catch (Exception ex)
                            {
                                UiThread.RunOnIdle(() =>
                                {
                                    ApplicationController.Instance.LogError($"Error adding file: {targetPath}\r\n{ex.Message}");
                                });
                            }

                            break;
                    }
                }
            });

            if (directoryWatcher != null)
            {
                // turn them back on
                directoryWatcher.EnableRaisingEvents = true;
            }

            if (this.isDirty)
            {
                this.ReloadContent();
            }
        }

        public void ApplyFilter(string filter, ILibraryContext libraryContext)
        {
            keywordFilter = filter;
            this.Load();
            this.OnContentChanged();
        }

        public void ClearFilter()
        {
            keywordFilter = null;
            this.Load();
            this.OnContentChanged();
        }

        public override void Deactivate()
        {
            this.isActiveContainer = false;
            base.Deactivate();
        }

        public override void Dispose()
        {
            if (directoryWatcher != null)
            {
                directoryWatcher.EnableRaisingEvents = false;

                directoryWatcher.Changed -= DirectoryContentsChanged;
                directoryWatcher.Created -= DirectoryContentsChanged;
                directoryWatcher.Deleted -= DirectoryContentsChanged;
                directoryWatcher.Renamed -= DirectoryContentsChanged;
            }
        }

        public override void Load()
        {
            this.Load(false);
        }

        public void Load(bool recursive)
        {
            SearchOption searchDepth = recursive ? SearchOption.AllDirectories : SearchOption.TopDirectoryOnly;

            try
            {
                string filter = keywordFilter?.Trim() ?? "";

                var allFiles = Directory.GetFiles(FullPath, "*.*", searchDepth);

                var zipFiles = allFiles.Where(f => Path.GetExtension(f).IndexOf(".zip", StringComparison.OrdinalIgnoreCase) != -1);

                var nonZipFiles = allFiles.Except(zipFiles);

                if (filter == "")
                {
                    var directories = Directory.GetDirectories(FullPath, "*.*", searchDepth).Select(p => new DirectoryContainerLink(p)).ToList<ILibraryContainerLink>();
                    this.ChildContainers = new SafeList<ILibraryContainerLink>(directories.Concat(zipFiles.Select(f => new LocalZipContainerLink(f))));
                    var libraryFiles = allFiles.Where(f => Path.GetExtension(f).IndexOf(".library", StringComparison.OrdinalIgnoreCase) != -1);
                    this.ChildContainers.AddRange(libraryFiles.Select(f => LibraryJsonFile.ContainerFromLocalFile(f)));
                }
                else
                {
                    this.ChildContainers = new SafeList<ILibraryContainerLink>();
                }

                var matchedFiles = nonZipFiles.Where(filePath =>
                {
                    string fileName = Path.GetFileName(filePath);

                    return (filter == "" || FileNameContainsFilter(filePath, filter))
                        && ApplicationController.Instance.Library.IsContentFileType(fileName);
                });

                this.ChildContainers.Modify((list) =>
                {
                    list.Sort((a, b) => a.Name.CompareTo(b.Name));
                });

                // Matched files projected onto FileSystemFileItem
                this.Items = new SafeList<ILibraryItem>(matchedFiles.OrderBy(f => f).Select(f => new FileSystemFileItem(f)));

                var indexMd = nonZipFiles.Where(f => f.EndsWith("index.md")).FirstOrDefault();
                if (indexMd != null)
                {
                    try
                    {
                        HeaderMarkdown = File.ReadAllText(indexMd);
                    }
                    catch { }
                }

                this.isDirty = false;
            }
            catch (Exception ex)
            {
                this.ChildContainers = new SafeList<ILibraryContainerLink>();
                this.Items = new SafeList<ILibraryItem>()
                {
                    new MessageItem("Error loading container - " + ex.Message)
                };
            }
        }

        public override void Remove(IEnumerable<ILibraryItem> items)
        {
            if (AggContext.OperatingSystem == OSType.Windows)
            {
                foreach (var item in items)
                {
                    if (item is FileSystemItem fileItem
                        && File.Exists(fileItem.FilePath))
                    {
                        File.Delete(fileItem.FilePath);
                    }
                }

                this.ReloadContent();
            }
        }

        private void DirectoryContentsChanged(object sender, EventArgs e)
        {
            // Flag for reload
            isDirty = true;

            lastTimeContentsChanged = UiThread.CurrentTimerMs;

            // Only refresh content if we're the active container
            if (isActiveContainer
                && waitingForRefresh == null)
            {
                waitingForRefresh = UiThread.SetInterval(WaitToRefresh, .5);
            }
        }

        private bool FileNameContainsFilter(string filename, string filter)
        {
            string nameWithSpaces = Path.GetFileNameWithoutExtension(filename.Replace('_', ' '));

            // Split the filter on word boundaries and determine if all terms in the given file name
            foreach (string word in filter.Split(' '))
            {
                if (nameWithSpaces.IndexOf(word, StringComparison.OrdinalIgnoreCase) == -1)
                {
                    return false;
                }
            }

            return true;
        }

        private string GetNonCollidingName(string fileName)
        {
            // Switching from .stl, .obj or similar to AMF. Save the file and update the
            // the filename with an incremented (n) value to reflect the extension change in the UI
            var similarFileNames = Directory.GetFiles(this.FullPath, $"{Path.GetFileNameWithoutExtension(fileName)}.*");

            // ;
            var validName = Util.GetNonCollidingName(fileName, (testName) => !File.Exists(testName));

            return validName;
        }

        private void WaitToRefresh()
        {
            if (UiThread.CurrentTimerMs > lastTimeContentsChanged + 500
                && waitingForRefresh != null)
            {
                UiThread.ClearInterval(waitingForRefresh);

                waitingForRefresh = null;
                this.ReloadContent();
            }
        }

        public class DirectoryContainerLink : FileSystemItem, ILibraryContainerLink
        {
            public DirectoryContainerLink(string path)
                : base(path)
            {
            }

            public bool IsReadOnly { get; set; } = false;

            public bool UseIncrementedNameDuringTypeChange { get; set; }

            public Task<ILibraryContainer> GetContainer(Action<double, string> reportProgress)
            {
                return Task.FromResult<ILibraryContainer>(
                    new FileSystemContainer(this.FilePath)
                    {
                        UseIncrementedNameDuringTypeChange = this.UseIncrementedNameDuringTypeChange,
                        Name = this.Name
                    });
            }
        }
    }
}