lmxopcua/src/Server/ZB.MOM.WW.OtOpcUa.Admin/Components/Pages/ScriptLog.razor

@page "/script-log"
@attribute [Microsoft.AspNetCore.Authorization.Authorize]
@rendermode RenderMode.InteractiveServer
@using Microsoft.AspNetCore.Components.Web
@using Microsoft.AspNetCore.SignalR.Client
@using ZB.MOM.WW.OtOpcUa.Admin.Hubs
@inject NavigationManager Nav
@inject AdminHubConnectionFactory HubFactory
@implements IAsyncDisposable

<h1 class="page-title">Script log viewer</h1>
<p class="text-muted">
    Live tail of the <code class="mono">scripts-*.log</code> file produced by the OPC UA Server's
    Roslyn script runtime. Useful for diagnosing virtual-tag and scripted-alarm script errors in production.
    Filter by script name to see only events from one script.
</p>

<div class="toolbar mb-3">
    <input class="form-control form-control-sm"
           style="max-width:22rem"
           placeholder="Filter by script name (optional)"
           @bind="_scriptNameFilter"
           @bind:event="oninput"
           disabled="@_streaming"/>
    <select class="form-select form-select-sm ms-2" style="max-width:10rem" @bind="_minLevel" disabled="@_streaming">
        <option value="VRB">All (VRB+)</option>
        <option value="DBG">DBG+</option>
        <option value="INF">INF+</option>
        <option value="WRN">WRN+</option>
        <option value="ERR">ERR+</option>
    </select>
    <button class="btn btn-sm btn-primary ms-2" @onclick="StartAsync" disabled="@_streaming">Start</button>
    <button class="btn btn-sm btn-outline-secondary ms-1" @onclick="StopAsync" disabled="@(!_streaming)">Stop</button>
    <button class="btn btn-sm btn-outline-danger ms-1" @onclick="ClearLines">Clear</button>
    <span class="spacer"></span>
    @if (_streaming)
    {
        <span class="chip chip-ok">Streaming</span>
    }
    else if (_stopped)
    {
        <span class="chip chip-idle">Stopped</span>
    }
    @if (_lines.Count > 0) { <span class="tb-count ms-2">@_lines.Count line@(_lines.Count == 1 ? "" : "s")</span> }
</div>

@if (_error is not null)
{
    <section class="panel notice rise" style="animation-delay:.02s">
        <span class="s-bad">@_error</span>
        <button type="button" class="btn-close float-end" @onclick="() => _error = null"></button>
    </section>
}

@if (_lines.Count == 0 && !_streaming && !_stopped)
{
    <section class="panel notice rise" style="animation-delay:.04s">
        Press <strong>Start</strong> to begin tailing the script log. The last @ScriptLogHub.TailSeedLines lines
        are replayed first, then new lines appear as they are written by the OPC UA Server script runtime.
    </section>
}
else if (_lines.Count == 0 && (_streaming || _stopped))
{
    <section class="panel notice rise" style="animation-delay:.04s">
        No matching log lines found. Check that the OPC UA Server is running and has executed at least one script,
        and that the <code class="mono">ScriptLog:Directory</code> setting points to the correct log folder.
    </section>
}
else
{
    <section class="panel rise" style="animation-delay:.08s">
        <div class="panel-head d-flex justify-content-between align-items-center">
            <span>Script log</span>
            <small class="text-muted">Latest @_lines.Count entries — oldest first</small>
        </div>
        <div class="table-wrap" style="max-height:60vh;overflow-y:auto" @ref="_tableContainer">
            <table class="data-table" style="font-size:.85rem">
                <thead>
                    <tr>
                        <th style="width:7rem">Level</th>
                        <th style="width:14rem">Script</th>
                        <th>Message</th>
                    </tr>
                </thead>
                <tbody>
                @foreach (var line in _lines)
                {
                    <tr class="@RowClass(line.Level)">
                        <td><span class="chip @LevelBadge(line.Level)">@line.Level</span></td>
                        <td><span class="mono small">@(line.ScriptName ?? "—")</span></td>
                        <td><span class="mono small" style="white-space:pre-wrap;word-break:break-all">@line.Raw</span></td>
                    </tr>
                }
                </tbody>
            </table>
        </div>
    </section>
}

@code {
    // Keep at most this many lines in-memory to avoid DOM growth.
    private const int MaxLines = 1000;

    private HubConnection? _hub;
    private CancellationTokenSource? _streamCts;
    private List<ScriptLogLine> _lines = [];
    private string _scriptNameFilter = string.Empty;
    private string _minLevel = "INF";
    private bool _streaming;
    private bool _stopped;
    private string? _error;
    private ElementReference _tableContainer;

    private static readonly string[] LevelOrder = ["VRB", "DBG", "INF", "WRN", "ERR", "FTL"];

    private async Task StartAsync()
    {
        _error = null;
        _streaming = false;
        _stopped = false;

        try
        {
            _hub ??= HubFactory.Create("/hubs/script-log");

            if (_hub.State == HubConnectionState.Disconnected)
                await _hub.StartAsync();

            _streamCts = new CancellationTokenSource();
            _streaming = true;

            // Fire-and-forget into the background; updates come via StateHasChanged.
            _ = Task.Run(() => ConsumeStreamAsync(_streamCts.Token));
        }
        catch (Exception ex)
        {
            _error = $"Failed to connect to script log hub: {ex.Message}";
            _streaming = false;
        }
    }

    private async Task ConsumeStreamAsync(CancellationToken ct)
    {
        try
        {
            var stream = _hub!.StreamAsync<ScriptLogLine>(
                "TailLogAsync", _scriptNameFilter, ct);

            await foreach (var line in stream.WithCancellation(ct))
            {
                if (!PassesLevelFilter(line.Level)) continue;

                await InvokeAsync(() =>
                {
                    _lines.Add(line);
                    if (_lines.Count > MaxLines)
                        _lines.RemoveRange(0, _lines.Count - MaxLines);
                    StateHasChanged();
                });
            }
        }
        catch (OperationCanceledException) { /* normal stop */ }
        catch (Exception ex)
        {
            await InvokeAsync(() =>
            {
                _error = $"Stream error: {ex.Message}";
                _streaming = false;
                _stopped = true;
                StateHasChanged();
            });
            return;
        }

        await InvokeAsync(() =>
        {
            _streaming = false;
            _stopped = true;
            StateHasChanged();
        });
    }

    private async Task StopAsync()
    {
        if (_streamCts is not null)
        {
            await _streamCts.CancelAsync();
            _streamCts.Dispose();
            _streamCts = null;
        }
        _streaming = false;
        _stopped = true;
    }

    private void ClearLines()
    {
        _lines.Clear();
        _stopped = false;
    }

    private bool PassesLevelFilter(string level)
    {
        var minIdx = Array.IndexOf(LevelOrder, _minLevel);
        var lineIdx = Array.IndexOf(LevelOrder, level);
        return lineIdx >= minIdx;
    }

    private static string LevelBadge(string level) => level switch
    {
        "ERR" or "FTL" => "chip-bad",
        "WRN" => "chip-warn",
        "INF" => "chip-ok",
        _ => "chip-idle",
    };

    private static string RowClass(string level) => level switch
    {
        "ERR" or "FTL" => "table-danger",
        "WRN" => "table-warning",
        _ => string.Empty,
    };

    public async ValueTask DisposeAsync()
    {
        if (_streamCts is not null)
        {
            await _streamCts.CancelAsync();
            _streamCts.Dispose();
        }
        if (_hub is not null)
        {
            await _hub.DisposeAsync();
            _hub = null;
        }
    }
}