@using LANCommander.SDK.Enums
@using LANCommander.Server.ImportExport
@using LANCommander.Server.ImportExport.Factories
@using LANCommander.Server.ImportExport.Models
@inherits FeedbackComponent<ImportDialogOptions>
@inject ArchiveService ArchiveService
@inject StorageLocationService StorageLocationService
@inject ImportContextFactory ImportContextFactory
@inject IMessageService MessageService
@inject ILogger<ImportUploadDialog> Logger

@if (_stage == ImportStage.Upload)
{
    <Flex Vertical Gap="FlexGap.Small">
        <ChunkUploader
            @ref="ChunkUploader"
            Accept=".lcx"
            @bind-File="File"
            @bind-Status="Status"
            StorageLocationId="StorageLocation.Id"
            OnUploadCompleted="OnUploadCompleted"
            OnUploadError="OnUploadError">
            <Text>
                <p>Drag and Drop</p>
                <p>or</p>
                <p>
                    <Button Type="@ButtonType.Primary" Style="margin-top: 8px;">Browse</Button>
                </p>
            </Text>
            <Hint>@Options.Hint</Hint>
        </ChunkUploader>

        <StorageLocationSelector @bind-Value="StorageLocation" Type="StorageLocationType.Archive"/>
    </Flex>
    
    <Flex Justify="FlexJustify.End" Gap="FlexGap.Small" Style="margin-top: 16px;">
        <FilePickerButton
            EntrySelectable="@(entry => !String.IsNullOrWhiteSpace(entry.Name) && entry.Name.ToLower().EndsWith(".lcx"))"
            OnSelected="OnLocalFileSelected"
            Root="@RootPath"
            Disabled="@(Status != "")">
            Use Local File
        </FilePickerButton>
        <Button OnClick="Upload" Disabled="@(File == null || Status != "")" Type="@ButtonType.Primary">Upload</Button>
        <Button OnClick="Cancel">Cancel</Button>
    </Flex>
}
else if (_stage == ImportStage.RecordSelection)
{
    <Tree TItem="string"
        Checkable
        Multiple
        CheckOnClickNode="false"
        @bind-CheckedKeys="_selectedKeys">
        @foreach (var group in ImportItems.GroupBy(i => i.Type))
        {
            var size = group.Sum(i => i.Size);
            
            <TreeNode Title="@($"{group.Key} ({group.Count()})")">
                <TitleTemplate>
                    <GridRow>
                        <GridCol Flex=@("auto")>
                            @group.Key.GetDisplayName() (@group.Count())
                        </GridCol>
                        
                        @if (size > 0)
                        {
                            <GridCol Flex=@("none")>
                                <ByteSize Value="@size" />
                            </GridCol>
                        }
                    </GridRow>
                </TitleTemplate>
                <ChildContent>
                    @foreach (var item in group)
                    {
                        <TreeNode Key="@item.Key">
                            <TitleTemplate>
                                <GridRow>
                                    <GridCol Flex=@("auto")>
                                        @item.Name
                                    </GridCol>

                                    @if (item.Size > 0)
                                    {
                                        <GridCol Flex=@("none")>
                                            <ByteSize Value="@item.Size"/>
                                        </GridCol>
                                    }
                                </GridRow>
                            </TitleTemplate>
                        </TreeNode>
                    }
                </ChildContent>
            </TreeNode>
        }
    </Tree>

    <Flex Justify="FlexJustify.End" Gap="FlexGap.Small" Style="margin-top: 16px;">
        <Button OnClick="Import" Type="@ButtonType.Primary">Import</Button>
        <Button OnClick="Cancel">Cancel</Button>
    </Flex>
}
else if (_stage == ImportStage.Importing)
{
    <Flex Align="FlexAlign.Center" Direction="FlexDirection.Vertical" Gap="FlexGap.Middle">
        <Progress Type="ProgressType.Circle" Percent="_importProgress" />
        
        @if (!String.IsNullOrWhiteSpace(_currentImportItemName))
        {
            <Text>Importing @_currentImportItemName</Text>
        }
        
        <Flex Gap="FlexGap.Small" Direction="FlexDirection.Vertical">
            @foreach (var error in _errors)
            {
                <Alert Type="AlertType.Error" Message="@error" />
            }
        </Flex>
    </Flex>
}
else if (_stage == ImportStage.Complete)
{
    <Result Status="ResultStatus.Success" Title="Import Complete!">
        <Extra>
            <Button Type="ButtonType.Primary" OnClick="CloseFeedbackAsync">Close</Button>
        </Extra>
    </Result>
}
else if (_stage == ImportStage.Failed)
{
    <Result Status="ResultStatus.Error" Title="Import Failed!">
        <Extra>
            <Flex Gap="FlexGap.Small" Direction="FlexDirection.Vertical">
                @foreach (var error in _errors)
                {
                    <Alert Type="AlertType.Error" Message="@error" />
                }
                
                <Button Type="ButtonType.Primary" OnClick="CloseFeedbackAsync">Close</Button>
            </Flex>
        </Extra>
    </Result>
}

@code {
    enum ImportStage
    {
        Upload,
        RecordSelection,
        Importing,
        Complete,
        Failed,
    };

    IBrowserFile File;
    ChunkUploader ChunkUploader;
    StorageLocation StorageLocation = new();
    ImportContext ImportContext;

    IEnumerable<IImportItemInfo> ImportItems = new List<IImportItemInfo>();
    
    string RootPath = Path.GetPathRoot(Directory.GetCurrentDirectory());

    bool IsValid = false;
    string Filename;
    string Status;

    ImportStage _stage = ImportStage.Upload;
    string[] _selectedKeys;

    List<string> _errors = new();

    int _importProgress = -1;
    int _importTotal = 0;
    string _currentImportItemName = String.Empty;

    protected override async Task OnInitializedAsync()
    {
        ImportContext = ImportContextFactory.Create();
        
        ImportContext.OnImportStarted.EventRaised += ImportStarted;
        ImportContext.OnImportComplete.EventRaised += ImportComplete;
        ImportContext.OnImportStatusUpdate.EventRaised += ImportStatusUpdate;
        ImportContext.OnImportError.EventRaised += ImportError;

        StorageLocation = await StorageLocationService.FirstAsync(l => l.Default && l.Type == StorageLocationType.Archive);
    }

    private async Task ImportStarted(ImportStatusUpdate status)
    {
        _stage = ImportStage.Importing;
        _importProgress = -1;
        
        await Task.Yield();
        await InvokeStateHasChangedAsync();
    }
    
    private async Task ImportComplete(ImportStatusUpdate status)
    {
        _stage = ImportStage.Complete;
        _importProgress = 100;
        
        await Clear();
        ImportContext.Dispose();
        
        await Task.Yield();
        await InvokeStateHasChangedAsync();
    }
    
    private async Task ImportStatusUpdate(ImportStatusUpdate status) => await UpdateProgress(status);

    private async Task ImportError(ImportStatusUpdate status)
    {
        if (status.Error != null)
            _errors.Add(status.Error);

        await Task.Yield();
        await InvokeStateHasChangedAsync();
    }
    
    private async Task UpdateProgress(ImportStatusUpdate? status)
    {
        if (status != null)
        {
            _importProgress = status.Total > 0 ? (int)Math.Floor(status.Index / (decimal)status.Total * 100) : 100;
            _currentImportItemName = $"{status.CurrentItem?.Type.GetDisplayName()}: {status.CurrentItem?.Name}";
            
            await Task.Yield();
            await InvokeStateHasChangedAsync();
        }
    }

    async Task Upload()
    {
        await ChunkUploader.Start();
    }

    async Task Import()
    {
        _stage = ImportStage.Importing;

        var selectedGuids = _selectedKeys
            .Select(k => Guid.TryParse(k, out var id) ? (Guid?)id : null)
            .Where(id => id.HasValue)
            .Select(g => g!.Value);
        
        try
        {
            await ImportContext.PrepareImportQueueAsync(selectedGuids, StorageLocation.Id);
            await ImportContext.ImportQueueAsync();
        }
        catch (Exception ex)
        {
            _stage = ImportStage.Failed;
            Logger?.LogError(ex, "An unknown error occurred while trying to import");
        }
    }

    async Task Clear()
    {
        await ChunkUploader.Clear();
    }

    async Task Cancel()
    {
        await ChunkUploader.Clear();
        await CloseFeedbackAsync();
    }

    public override async Task OnFeedbackCancelAsync(ModalClosingEventArgs args)
    {
        await Clear();

        ImportContext.Dispose();

        await base.OnFeedbackCancelAsync(args);
    }

    public override async Task OnFeedbackOkAsync(ModalClosingEventArgs args)
    {
        await ChunkUploader.Clear();
        
        ImportContext.Dispose();

        await base.OnFeedbackOkAsync(args);
    }

    public async Task OnUploadCompleted(string data)
    {
        if (Guid.TryParse(data, out var objectKey))
        {
            try
            {
                var archivePath = await ArchiveService.GetArchiveFileLocationAsync(objectKey.ToString());

                ImportItems = await ImportContext.InitializeImportAsync(archivePath);

                _selectedKeys = ImportItems.Select(i => i.Key).ToArray();
                
                _stage = ImportStage.RecordSelection;

                await InvokeAsync(StateHasChanged);
            }
            catch (Exception ex)
            {
                Logger?.LogError(ex, "An unknown error occurred while trying to import");
                MessageService.Error("An unknown error occurred while trying to import");
            }
        }
        else
        {
            await InvokeAsync(StateHasChanged);

            MessageService.Error("Import file failed to upload!");
            Logger.LogError("Import file failed to upload!");

            await (base.OkCancelRef?.OnCancel?.Invoke() ?? Task.CompletedTask);
            await CloseFeedbackAsync();
        }

        await Clear();
    }

    public async Task OnUploadError(string message)
    {
        await InvokeAsync(StateHasChanged);

        MessageService.Error("An error occurred while trying to import");
        Logger?.LogError($"An error occurred while trying to import: {message}");

        await CloseFeedbackAsync();
    }

    public async Task OnLocalFileSelected(string path)
    {
        try
        {
            ImportItems = await ImportContext.InitializeImportAsync(path);
            
            _selectedKeys = ImportItems.Select(i => i.Key).ToArray();
            
            _stage = ImportStage.RecordSelection;

            await InvokeAsync(StateHasChanged);
        }
        catch (Exception ex)
        {
            Logger?.LogError(ex, "An unknown error occurred while trying to import");
            MessageService.Error("An unknown error occurred while trying to import");
        }
    }
}