Plugins - Adjusted namespaces

src/Artemis.Core/Plugins/Plugin.cs

@@ -0,0 +1,137 @@
+using System;
+using System.Threading.Tasks;
+using Artemis.Core.Plugins.Exceptions;
+
+namespace Artemis.Core.Plugins
+{
+    /// <summary>
+    ///     This is the base plugin type, use the other interfaces such as Module to create plugins
+    /// </summary>
+    public abstract class Plugin : IDisposable
+    {
+        /// <summary>
+        ///     Gets the plugin info related to this plugin
+        /// </summary>
+        public PluginInfo PluginInfo { get; internal set; }
+
+        /// <summary>
+        ///     Gets whether the plugin is enabled
+        /// </summary>
+        public bool Enabled { get; private set; }
+        
+        /// <summary>
+        ///     Gets or sets a configuration dialog for this plugin that is accessible in the UI under Settings > Plugins
+        /// </summary>
+        public PluginConfigurationDialog ConfigurationDialog { get; protected set; }
+
+        /// <inheritdoc />
+        public void Dispose()
+        {
+            DisablePlugin();
+        }
+
+        /// <summary>
+        ///     Called when the plugin is activated
+        /// </summary>
+        public abstract void EnablePlugin();
+
+        /// <summary>
+        ///     Called when the plugin is deactivated or when Artemis shuts down
+        /// </summary>
+        public abstract void DisablePlugin();
+
+        internal void SetEnabled(bool enable, bool isAutoEnable = false)
+        {
+            if (enable && !Enabled)
+            {
+                try
+                {
+                    if (isAutoEnable && PluginInfo.GetLockFileCreated())
+                    {
+                        // Don't wrap existing lock exceptions, simply rethrow them
+                        if (PluginInfo.LoadException is ArtemisPluginLockException)
+                            throw PluginInfo.LoadException;
+
+                        throw new ArtemisPluginLockException(PluginInfo.LoadException);
+                    }
+
+                    Enabled = true;
+                    PluginInfo.Enabled = true;
+                    PluginInfo.CreateLockFile();
+
+                    // Allow up to 15 seconds for plugins to activate.
+                    // This means plugins that need more time should do their long running tasks in a background thread, which is intentional
+                    // Little meh: Running this from a different thread could cause deadlocks
+                    var enableTask = Task.Run(InternalEnablePlugin);
+                    if (!enableTask.Wait(TimeSpan.FromSeconds(15)))
+                        throw new ArtemisPluginException(PluginInfo, "Plugin load timeout");
+
+                    PluginInfo.LoadException = null;
+                    OnPluginEnabled();
+                }
+                // If enable failed, put it back in a disabled state
+                catch (Exception e)
+                {
+                    Enabled = false;
+                    PluginInfo.Enabled = false;
+                    PluginInfo.LoadException = e;
+                    throw;
+                }
+                finally
+                {
+                    if (!(PluginInfo.LoadException is ArtemisPluginLockException))
+                        PluginInfo.DeleteLockFile();
+                }
+            }
+            else if (!enable && Enabled)
+            {
+                Enabled = false;
+                PluginInfo.Enabled = false;
+
+                // Even if disable failed, still leave it in a disabled state to avoid more issues
+                InternalDisablePlugin();
+                OnPluginDisabled();
+            }
+        }
+
+        internal virtual void InternalEnablePlugin()
+        {
+            EnablePlugin();
+        }
+
+        internal virtual void InternalDisablePlugin()
+        {
+            DisablePlugin();
+        }
+
+        #region Events
+
+        /// <summary>
+        ///     Occurs when the plugin is enabled
+        /// </summary>
+        public event EventHandler PluginEnabled;
+
+        /// <summary>
+        ///     Occurs when the plugin is disabled
+        /// </summary>
+        public event EventHandler PluginDisabled;
+
+        /// <summary>
+        ///     Triggers the PluginEnabled event
+        /// </summary>
+        protected virtual void OnPluginEnabled()
+        {
+            PluginEnabled?.Invoke(this, EventArgs.Empty);
+        }
+
+        /// <summary>
+        ///     Triggers the PluginDisabled event
+        /// </summary>
+        protected virtual void OnPluginDisabled()
+        {
+            PluginDisabled?.Invoke(this, EventArgs.Empty);
+        }
+
+        #endregion
+    }
+}