@page "/tracks"
@using System.Net
@using DeepDrftManager.Services
@using DeepDrftModels.DTOs
@attribute [Authorize]
@inject ICmsTrackService CmsTrackService
@inject IDialogService DialogService
@inject ISnackbar Snackbar
@inject ILogger<TrackList> Logger

<PageTitle>Tracks — DeepDrft CMS</PageTitle>

<MudContainer MaxWidth="MaxWidth.Large" Class="mt-8">
    <MudText Typo="Typo.h3" Class="mb-4">Tracks</MudText>

    <MudTabs Elevation="0" Rounded="false" ApplyEffectsToContainer="true" PanelClass="pt-4">
        <MudTabPanel Text="Tracks" Icon="@Icons.Material.Filled.LibraryMusic">
            <MudStack Row="true" Justify="Justify.FlexEnd" Class="mb-2">
                <MudButton Variant="Variant.Filled"
                           Color="Color.Primary"
                           StartIcon="@Icons.Material.Filled.Add"
                           Href="/tracks/new">
                    Add Track
                </MudButton>
            </MudStack>

            <MudTable T="TrackDto"
                      @ref="_table"
                      ServerData="LoadServerData"
                      Hover="true"
                      Striped="true"
                      Dense="true"
                      Bordered="false"
                      FixedHeader="true"
                      RowsPerPage="20"
                      AllowUnsorted="false">
                <NoRecordsContent>
                    <MudText Typo="Typo.body1">No tracks found.</MudText>
                </NoRecordsContent>
                <LoadingContent>
                    <MudText Typo="Typo.body1">Loading tracks…</MudText>
                </LoadingContent>
                <HeaderContent>
                    <MudTh><MudTableSortLabel SortLabel="TrackName" T="TrackDto" InitialDirection="SortDirection.Ascending">Track Name</MudTableSortLabel></MudTh>
                    <MudTh><MudTableSortLabel SortLabel="Artist" T="TrackDto">Artist</MudTableSortLabel></MudTh>
                    <MudTh><MudTableSortLabel SortLabel="Album" T="TrackDto">Album</MudTableSortLabel></MudTh>
                    <MudTh><MudTableSortLabel SortLabel="Genre" T="TrackDto">Genre</MudTableSortLabel></MudTh>
                    <MudTh><MudTableSortLabel SortLabel="ReleaseDate" T="TrackDto">Release Date</MudTableSortLabel></MudTh>
                    <MudTh>Entry Key</MudTh>
                    <MudTh Style="width: 1%; white-space: nowrap;">Actions</MudTh>
                </HeaderContent>
                <RowTemplate>
                    <MudTd DataLabel="Track Name">@context.TrackName</MudTd>
                    <MudTd DataLabel="Artist">@context.Artist</MudTd>
                    <MudTd DataLabel="Album">@(context.Album ?? "—")</MudTd>
                    <MudTd DataLabel="Genre">@(context.Genre ?? "—")</MudTd>
                    <MudTd DataLabel="Release Date">@(context.ReleaseDate?.ToString("yyyy-MM-dd") ?? "—")</MudTd>
                    <MudTd DataLabel="Entry Key"><MudText Typo="Typo.caption" Style="font-family: monospace;">@context.EntryKey</MudText></MudTd>
                    <MudTd DataLabel="Actions">
                        <MudTooltip Text="Edit">
                            <MudIconButton Icon="@Icons.Material.Filled.Edit"
                                           Size="Size.Small"
                                           Color="Color.Primary"
                                           Href="@($"/tracks/{context.Id}")" />
                        </MudTooltip>
                        <MudTooltip Text="Delete">
                            <MudIconButton Icon="@Icons.Material.Filled.Delete"
                                           Size="Size.Small"
                                           Color="Color.Error"
                                           OnClick="@(() => ConfirmAndDelete(context))" />
                        </MudTooltip>
                    </MudTd>
                </RowTemplate>
                <PagerContent>
                    <MudTablePager PageSizeOptions="new[] { 10, 20, 50 }" />
                </PagerContent>
            </MudTable>
        </MudTabPanel>

        <MudTabPanel Text="Waveform Pre-Processing" Icon="@Icons.Material.Filled.GraphicEq">
            <MudStack Row="true" AlignItems="AlignItems.Center" Justify="Justify.SpaceBetween" Class="mb-4">
                <MudStack Spacing="0">
                    <MudText Typo="Typo.h5">Waveform Pre-Processing</MudText>
                    <MudText Typo="Typo.body2" Class="mud-text-secondary">
                        Generate loudness profiles for tracks that predate the waveform seeker.
                    </MudText>
                </MudStack>
                <MudButton Variant="Variant.Filled"
                           Color="Color.Primary"
                           StartIcon="@Icons.Material.Filled.AutoFixHigh"
                           Disabled="@(_bulkRunning || _missingCount == 0)"
                           OnClick="GenerateAllMissing">
                    @if (_bulkRunning)
                    {
                        <MudProgressCircular Class="mr-2" Size="Size.Small" Indeterminate="true" />
                        <span>Generating @_bulkDone / @_bulkTotal…</span>
                    }
                    else
                    {
                        <span>Generate All Missing (@_missingCount)</span>
                    }
                </MudButton>
            </MudStack>

            <MudTable T="WaveformStatusDto"
                      Items="_waveformRows"
                      Loading="_waveformLoading"
                      Hover="true"
                      Striped="true"
                      Dense="true"
                      Bordered="false"
                      FixedHeader="true">
                <NoRecordsContent>
                    <MudText Typo="Typo.body1">No tracks found.</MudText>
                </NoRecordsContent>
                <LoadingContent>
                    <MudText Typo="Typo.body1">Loading waveform status…</MudText>
                </LoadingContent>
                <HeaderContent>
                    <MudTh>Track Name</MudTh>
                    <MudTh>Entry Key</MudTh>
                    <MudTh Style="width: 1%; white-space: nowrap;">Profile</MudTh>
                    <MudTh Style="width: 1%; white-space: nowrap;">Actions</MudTh>
                </HeaderContent>
                <RowTemplate>
                    <MudTd DataLabel="Track Name">@context.TrackName</MudTd>
                    <MudTd DataLabel="Entry Key">
                        <MudText Typo="Typo.caption" Style="font-family: monospace;">@context.EntryKey</MudText>
                    </MudTd>
                    <MudTd DataLabel="Profile">
                        @if (context.HasProfile)
                        {
                            <MudChip T="string" Size="Size.Small" Color="Color.Success" Variant="Variant.Text"
                                     Icon="@Icons.Material.Filled.CheckCircle">Stored</MudChip>
                        }
                        else
                        {
                            <MudChip T="string" Size="Size.Small" Color="Color.Warning" Variant="Variant.Text"
                                     Icon="@Icons.Material.Filled.Cancel">Missing</MudChip>
                        }
                    </MudTd>
                    <MudTd DataLabel="Actions">
                        @if (!context.HasProfile)
                        {
                            <MudButton Variant="Variant.Outlined"
                                       Size="Size.Small"
                                       Color="Color.Primary"
                                       StartIcon="@Icons.Material.Filled.GraphicEq"
                                       Disabled="@(_bulkRunning || IsGenerating(context.EntryKey))"
                                       OnClick="@(() => GenerateOne(context))">
                                @if (IsGenerating(context.EntryKey))
                                {
                                    <MudProgressCircular Class="mr-2" Size="Size.Small" Indeterminate="true" />
                                    <span>Generating…</span>
                                }
                                else
                                {
                                    <span>Generate</span>
                                }
                            </MudButton>
                        }
                    </MudTd>
                </RowTemplate>
            </MudTable>
        </MudTabPanel>
    </MudTabs>
</MudContainer>

@code {
    // Track list fields
    private MudTable<TrackDto>? _table;

    // Waveform fields
    private List<WaveformStatusDto> _waveformRows = new();
    private readonly HashSet<string> _generating = new();
    private bool _waveformLoading = true;
    private bool _bulkRunning;
    private int _bulkTotal;
    private int _bulkDone;

    private int _missingCount => _waveformRows.Count(r => !r.HasProfile);

    protected override async Task OnInitializedAsync()
    {
        await LoadWaveformStatus();
    }

    // ── Track list methods ──────────────────────────────────────────────────

    private async Task<TableData<TrackDto>> LoadServerData(TableState state, CancellationToken cancellationToken)
    {
        var pageNumber = state.Page + 1; // MudTable is 0-based, service is 1-based.
        var sortColumn = string.IsNullOrEmpty(state.SortLabel) ? "TrackName" : state.SortLabel;
        var sortDescending = state.SortDirection == SortDirection.Descending;

        var result = await CmsTrackService.GetPagedAsync(pageNumber, state.PageSize, sortColumn, sortDescending, cancellationToken);

        if (!result.Success || result.Value is null)
        {
            var errorText = result.Messages.FirstOrDefault()?.Message ?? "Unknown error";
            Snackbar.Add($"Failed to load tracks: {errorText}", Severity.Error);
            return new TableData<TrackDto> { Items = Array.Empty<TrackDto>(), TotalItems = 0 };
        }

        var page = result.Value;
        return new TableData<TrackDto>
        {
            Items = page.Items,
            TotalItems = page.TotalCount
        };
    }

    private async Task ConfirmAndDelete(TrackDto track)
    {
        var confirmed = await DialogService.ShowMessageBox(
            title: "Delete track",
            markupMessage: new MarkupString($"Delete <strong>{WebUtility.HtmlEncode(track.TrackName)}</strong> by {WebUtility.HtmlEncode(track.Artist)}? This removes both the metadata row and the underlying audio entry."),
            yesText: "Delete",
            cancelText: "Cancel");

        if (confirmed != true) return;

        try
        {
            var result = await CmsTrackService.DeleteTrackAsync(track.Id);
            if (result.Success)
            {
                Snackbar.Add($"Deleted '{track.TrackName}'.", Severity.Success);
                if (_table is not null) await _table.ReloadServerData();
            }
            else
            {
                var error = result.Messages.FirstOrDefault()?.Message ?? "Unknown error";
                Snackbar.Add($"Delete failed: {error}", Severity.Error);
            }
        }
        catch (Exception ex)
        {
            Logger.LogError(ex, "Delete failed for track {TrackId}", track.Id);
            Snackbar.Add("Delete failed — please try again.", Severity.Error);
        }
    }

    // ── Waveform pre-processing methods ────────────────────────────────────

    private async Task LoadWaveformStatus()
    {
        _waveformLoading = true;
        var result = await CmsTrackService.GetWaveformStatusAsync();
        _waveformLoading = false;

        if (!result.Success || result.Value is null)
        {
            var error = result.Messages.FirstOrDefault()?.Message ?? "Unknown error";
            Snackbar.Add($"Failed to load waveform status: {error}", Severity.Error);
            _waveformRows = new List<WaveformStatusDto>();
            return;
        }

        _waveformRows = result.Value.OrderBy(r => r.HasProfile).ThenBy(r => r.TrackName).ToList();
    }

    private bool IsGenerating(string entryKey) => _generating.Contains(entryKey);

    private async Task GenerateOne(WaveformStatusDto row)
    {
        if (!await GenerateForRow(row))
        {
            return;
        }

        Snackbar.Add($"Generated profile for '{row.TrackName}'.", Severity.Success);
    }

    private async Task GenerateAllMissing()
    {
        var missing = _waveformRows.Where(r => !r.HasProfile).ToList();
        if (missing.Count == 0)
        {
            return;
        }

        _bulkRunning = true;
        _bulkTotal = missing.Count;
        _bulkDone = 0;
        var failures = 0;

        // Sequential by design: one request at a time so a large backfill does not flood the API
        // with concurrent WAV decodes.
        foreach (var row in missing)
        {
            if (!await GenerateForRow(row))
            {
                failures++;
            }
            _bulkDone++;
            StateHasChanged();
        }

        _bulkRunning = false;

        var succeeded = missing.Count - failures;
        if (failures == 0)
        {
            Snackbar.Add($"Generated {succeeded} profile(s).", Severity.Success);
        }
        else
        {
            Snackbar.Add($"Generated {succeeded} profile(s); {failures} failed.", Severity.Warning);
        }
    }

    /// <summary>
    /// Runs generation for a single row, flipping its status on success. Returns false on failure
    /// (a snackbar is raised here for the per-row path; the bulk path aggregates a summary). Marks
    /// the row busy for the duration so its button shows a spinner and stays disabled.
    /// </summary>
    private async Task<bool> GenerateForRow(WaveformStatusDto row)
    {
        _generating.Add(row.EntryKey);
        StateHasChanged();
        try
        {
            var result = await CmsTrackService.GenerateWaveformProfileAsync(row.EntryKey);
            if (result.Success)
            {
                row.HasProfile = true;
                return true;
            }

            var error = result.Messages.FirstOrDefault()?.Message ?? "Unknown error";
            if (!_bulkRunning)
            {
                Snackbar.Add($"Generate failed for '{row.TrackName}': {error}", Severity.Error);
            }
            return false;
        }
        catch (Exception ex)
        {
            Logger.LogError(ex, "Waveform generation failed for {EntryKey}", row.EntryKey);
            if (!_bulkRunning)
            {
                Snackbar.Add($"Generate failed for '{row.TrackName}' — please try again.", Severity.Error);
            }
            return false;
        }
        finally
        {
            _generating.Remove(row.EntryKey);
            StateHasChanged();
        }
    }
}