@page "/"
@using System.Net.Http.Headers
@using Microsoft.Extensions.Configuration
@implements IAsyncDisposable
@inject HttpClient Http
@inject IJSRuntime JS
@inject IConfiguration Configuration

<PageTitle>Upload your form</PageTitle>
<AuthorizeView>
    <Authorized>
        <div class="input-group mb-3">
            <InputFile @key="_inputFileGuid" @ref="inputFile" id="input-file" class="form-control" disable="@_fileSelectionDisable" OnChange="@LoadFile" aria-describedby="button-upload" />
            <button id="button-reset" class="btn btn-outline-primary" disabled="@_buttonsDisable" @onclick="OnResetClick">Reset</button>
            <button id="button-upload" class="btn btn-outline-primary" disabled="@_buttonsDisable" @onclick="OnUploadClick">Upload</button>
        </div>
        <img class="img-thumbnail" id="selectedImage" hidden="@_buttonsDisable" />
    </Authorized>
    <NotAuthorized>
        You must be signed in to upload your form
    </NotAuthorized>
</AuthorizeView>

@code {
    private IJSObjectReference? _module;
    private bool _buttonsDisable = true;
    private bool _fileSelectionDisable = false;
    private Guid _inputFileGuid = Guid.NewGuid();
    private InputFile? inputFile;
    private IBrowserFile? _imageFile;


    protected override async Task OnAfterRenderAsync(bool firstRender)
    {
        if (firstRender)
        {
            _module = await JS.InvokeAsync<IJSObjectReference>("import", "./Pages/Upload.razor.js");
        }
        await base.OnAfterRenderAsync(firstRender);
    }

    private async Task<string> GetPresignedUrl()
    {
        var request = new HttpRequestMessage()
            {
                Method = HttpMethod.Get,
                RequestUri = new Uri(Configuration["GetPresignedUrl"])
            };
        request.SetBrowserRequestCredentials(BrowserRequestCredentials.Include);
        var response = await Http.SendAsync(request);
        string presignedUrl = await response.Content.ReadAsStringAsync();
        return presignedUrl;
    }

    private async Task OnResetClick()
    {
        await Reset();
    }

    private async Task Reset()
    {
        _buttonsDisable = true;
        if (inputFile is not null)
        {
            _inputFileGuid = Guid.NewGuid();
        }
        if (_module is not null)
        {
            await _module.InvokeVoidAsync("resetImage", "selectedImage");
        }
        if(_imageFile is not null)
        {
            _imageFile = null;
        }
    }

    private async Task OnUploadClick()
    {
        if (_imageFile != null)
        {
            string presignedUrl = await GetPresignedUrl();
            using (Stream imageStream = _imageFile.OpenReadStream())
            {
                HttpContent content = new StreamContent(imageStream);
                content.Headers.ContentType = new MediaTypeHeaderValue("image/jpeg");
                var response = await Http.PutAsync(presignedUrl, content);

                if (response.IsSuccessStatusCode)
                {
                    await Reset();
                }
            }
        }
    }

    private async Task LoadFile(InputFileChangeEventArgs e)
    {
        _buttonsDisable = false;
        _imageFile = e.File;
        using (DotNetStreamReference dotnetImageStream = new DotNetStreamReference(_imageFile.OpenReadStream()))
        {
            if (_module is not null)
            {
                await _module.InvokeVoidAsync("setImageUsingStreaming", "selectedImage", dotnetImageStream);
            }
        }
    }

    async ValueTask IAsyncDisposable.DisposeAsync()
    {
        if (_module is not null)
        {
            await _module.InvokeVoidAsync("disposeUrl");
            await _module.DisposeAsync();
        }
    }
}