initial framework for gsc + iw4madmin integration

improvements to script plugin capabilities and error feedback

Application/Misc/ScriptPluginTimerHelper.cs

@@ -0,0 +1,157 @@
+using System;
+using System.Threading;
+using Jint.Native;
+using Jint.Runtime;
+using Microsoft.Extensions.Logging;
+using SharedLibraryCore.Interfaces;
+using ILogger = Microsoft.Extensions.Logging.ILogger;
+
+namespace IW4MAdmin.Application.Misc;
+
+public class ScriptPluginTimerHelper : IScriptPluginTimerHelper
+{
+    private Timer _timer;
+    private Action _actions;
+    private Delegate _jsAction;
+    private string _actionName;
+    private const int DefaultDelay = 0;
+    private const int DefaultInterval = 1000;
+    private readonly ILogger _logger;
+    private readonly ManualResetEventSlim _onRunningTick = new();
+    private SemaphoreSlim _onDependentAction;
+
+    public ScriptPluginTimerHelper(ILogger<ScriptPluginTimerHelper> logger)
+    {
+        _logger = logger;
+    }
+
+    ~ScriptPluginTimerHelper()
+    {
+        if (_timer != null)
+        {
+            Stop();
+        }
+        _onRunningTick.Dispose();
+    }
+
+    public void Start(int delay, int interval)
+    {
+        if (_actions is null)
+        {
+            throw new InvalidOperationException("Timer action must be defined before starting");
+        }
+
+        if (delay < 0)
+        {
+            throw new ArgumentException("Timer delay must be >= 0");
+        }
+
+        if (interval < 20)
+        {
+            throw new ArgumentException("Timer interval must be at least 20ms");
+        }
+        
+        Stop();
+        
+        _logger.LogDebug("Starting script timer...");
+
+        _onRunningTick.Set();
+        _timer ??= new Timer(callback => _actions(), null, delay, interval);
+        IsRunning = true;
+    }
+
+    public void Start(int interval)
+    {
+        Start(DefaultDelay, interval);
+    }
+
+    public void Start()
+    {
+        Start(DefaultDelay, DefaultInterval);
+    }
+
+    public void Stop()
+    {
+        if (_timer == null)
+        {
+            return;
+        }
+        
+        _logger.LogDebug("Stopping script timer...");
+        _timer.Change(Timeout.Infinite, Timeout.Infinite);
+        _timer.Dispose();
+        _timer = null;
+        IsRunning = false;
+    }
+
+    public void OnTick(Delegate action, string actionName)
+    {
+        if (string.IsNullOrEmpty(actionName))
+        {
+            throw new ArgumentException("actionName must be provided", nameof(actionName));
+        }
+
+        if (action is null)
+        {
+            throw new ArgumentException("action must be provided", nameof(action));
+        }
+
+        _logger.LogDebug("Adding new action with name {ActionName}", actionName);
+
+        _jsAction = action;
+        _actionName = actionName;
+        _actions = OnTick;
+    }
+
+    private void ReleaseThreads()
+    {
+        _onRunningTick.Set();
+
+        if (_onDependentAction?.CurrentCount != 0)
+        {
+            return;
+        }
+
+        _onDependentAction?.Release(1);
+    }
+    private void OnTick()
+    {
+        try
+        {
+            if (!_onRunningTick.IsSet)
+            {
+                _logger.LogWarning("Previous {OnTick} is still running, so we are skipping this one",
+                    nameof(OnTick));
+                return;
+            }
+
+            _onRunningTick.Reset();
+
+            // the js engine is not thread safe so we need to ensure we're not executing OnTick and OnEventAsync simultaneously
+            _onDependentAction?.WaitAsync().Wait();
+            _jsAction.DynamicInvoke(JsValue.Undefined, new[] { JsValue.Undefined });
+            ReleaseThreads();
+        }
+
+        catch (Exception ex) when (ex.InnerException is JavaScriptException jsex)
+        {
+            _logger.LogError(jsex,
+                "Could not execute timer tick for script action {ActionName} [@{LocationInfo}]", _actionName,
+                jsex.Location);
+            ReleaseThreads();
+        }
+        catch (Exception ex)
+        {
+            _logger.LogError(ex, "Could not execute timer tick for script action {ActionName}", _actionName);
+            _onRunningTick.Set();
+            ReleaseThreads();
+        }
+    }
+
+    public void SetDependency(SemaphoreSlim dependentSemaphore)
+    {
+        _onDependentAction = dependentSemaphore;
+    }
+
+    public bool IsRunning { get; private set; }
+}