@page "/channels/{Id:int?}"
@page "/channels/add"
@using ErsatzTV.Application.FFmpegProfiles
@using ErsatzTV.Application.FFmpegProfiles.Queries
@using ErsatzTV.Application.Images.Commands
@using ErsatzTV.Application.Channels
@using ErsatzTV.Application.Channels.Queries
@inject NavigationManager NavigationManager
@inject ILogger<ChannelEditor> Logger
@inject ISnackbar Snackbar
@inject IMediator Mediator

<div style="max-width: 400px;">
    <MudText Typo="Typo.h4" Class="mb-4">@(IsEdit ? "Edit Channel" : "Add Channel")</MudText>

    <EditForm EditContext="_editContext" OnSubmit="@HandleSubmitAsync">
        <FluentValidator/>
        <MudCard>
            <MudCardContent>
                <MudTextField Label="Number" @bind-Value="_model.Number" For="@(() => _model.Number)" Immediate="true"/>
                <MudTextField Class="mt-3" Label="Name" @bind-Value="_model.Name" For="@(() => _model.Name)"/>
                <MudSelect Class="mt-3" Label="Streaming Mode" @bind-Value="_model.StreamingMode" For="@(() => _model.StreamingMode)">
                    @foreach (StreamingMode streamingMode in Enum.GetValues<StreamingMode>())
                    {
                        <MudSelectItem Value="@streamingMode">@streamingMode</MudSelectItem>
                    }
                </MudSelect>
                <MudSelect Class="mt-3" Label="FFmpeg Profile" @bind-Value="_model.FFmpegProfileId" For="@(() => _model.FFmpegProfileId)"
                           Disabled="@(_model.StreamingMode != StreamingMode.TransportStream)">
                    @foreach (FFmpegProfileViewModel profile in _ffmpegProfiles)
                    {
                        <MudSelectItem Value="@profile.Id">@profile.Name</MudSelectItem>
                    }
                </MudSelect>
                <MudGrid Class="mt-3" Style="align-items: center" Justify="Justify.Center">
                    <MudItem xs="6">
                        <InputFile id="fileInput" OnChange="UploadLogo" hidden/>
                        @if (!string.IsNullOrWhiteSpace(_model.Logo))
                        {
                            <MudElement HtmlTag="img" src="@($"iptv/images/{_model.Logo}")" Style="max-height: 50px"/>
                        }
                    </MudItem>
                    <MudItem xs="6">
                        <MudButton Class="ml-auto" HtmlTag="label"
                                   Variant="Variant.Filled"
                                   Color="Color.Primary"
                                   StartIcon="@Filled.CloudUpload"
                                   for="fileInput">
                            Upload Logo
                        </MudButton>
                    </MudItem>
                </MudGrid>
            </MudCardContent>
            <MudCardActions>
                <MudButton ButtonType="ButtonType.Submit" Variant="Variant.Filled" Color="Color.Primary">
                    @(IsEdit ? "Save Changes" : "Add Channel")
                </MudButton>
            </MudCardActions>
        </MudCard>
    </EditForm>
</div>

@code {

    [Parameter]
    public int? Id { get; set; }

    private readonly ChannelEditViewModel _model = new();
    private EditContext _editContext;
    private ValidationMessageStore _messageStore;

    private List<FFmpegProfileViewModel> _ffmpegProfiles;

    protected override async Task OnParametersSetAsync()
    {
        await LoadFFmpegProfilesAsync();

        if (Id.HasValue)
        {
            Option<ChannelViewModel> maybeChannel = await Mediator.Send(new GetChannelById(Id.Value));
            maybeChannel.Match(
                channelViewModel =>
                {
                    _model.Id = channelViewModel.Id;
                    _model.Name = channelViewModel.Name;
                    _model.Number = channelViewModel.Number;
                    _model.FFmpegProfileId = channelViewModel.FFmpegProfileId;
                    _model.Logo = channelViewModel.Logo;
                    _model.StreamingMode = channelViewModel.StreamingMode;
                },
                () => NavigationManager.NavigateTo("404"));
        }
        else
        {
    // TODO: command for new channel
            int maxNumber = await Mediator.Send(new GetAllChannels()).Map(channels => channels.Max(c => c.Number));
            _model.Number = maxNumber + 1;
            _model.Name = "New Channel";
            _model.FFmpegProfileId = _ffmpegProfiles.Head().Id;
            _model.StreamingMode = StreamingMode.TransportStream;
        }
    }

    protected override void OnInitialized()
    {
        _editContext = new EditContext(_model);
        _messageStore = new ValidationMessageStore(_editContext);
    }

    private bool IsEdit => Id.HasValue;

    private async Task LoadFFmpegProfilesAsync() =>
        _ffmpegProfiles = await Mediator.Send(new GetAllFFmpegProfiles());

    private async Task HandleSubmitAsync()
    {
        _messageStore.Clear();
        if (_editContext.Validate())
        {
            Seq<BaseError> errorMessage = IsEdit ?
                (await Mediator.Send(_model.ToUpdate())).LeftToSeq() :
                (await Mediator.Send(_model.ToCreate())).LeftToSeq();

            errorMessage.HeadOrNone().Match(
                error =>
                {
                    Snackbar.Add($"Unexpected error saving channel: {error.Value}");
                    Logger.LogError("Unexpected error saving channel: {Error}", error.Value);
                },
                () => NavigationManager.NavigateTo("/channels"));
        }
    }

    private async Task UploadLogo(InputFileChangeEventArgs e)
    {
        var buffer = new byte[e.File.Size];
        await e.File.OpenReadStream().ReadAsync(buffer);
        Either<BaseError, string> maybeCacheFileName = await Mediator.Send(new SaveImageToDisk(buffer));
        maybeCacheFileName.Match(
            relativeFileName => _model.Logo = relativeFileName,
            error =>
            {
                Snackbar.Add($"Unexpected error saving channel logo: {error.Value}");
                Logger.LogError("Unexpected error saving channel logo: {Error}", error.Value);
            });
    }

}