handle updates with a queue, display favourite status, removed status bar

MainWindow.cs

@@ -28,23 +28,14 @@ using System.Diagnostics;
 using Gtk;
 
 namespace Buypeeb {
-	public struct ItemColumns {
-		public const int Name = 0;
-		public const int PriceYen = 1;
-		public const int PriceAUD = 2;
-		public const int Ending = 3;
-		public const int Id = 4;
-	}
 
 	class MainWindow : Window {
 
 		private string location;
-		// private Queue<string> statuses;
 
 		private ListStore items;
 		private Settings settings;
 		private TreeView itemTreeView;
-		private Label statusLabel;
 		private Builder builder;
 
 		// TODO: whenever we get something from the builder, cache it for later
@@ -53,10 +44,12 @@ namespace Buypeeb {
 
 		private Box selectionViewBox;
 		private Label endingLabel;
+		private bool queueActive;
 
 		// ...to here.
 
-		static SemaphoreSlim taskLimit = new SemaphoreSlim(4);
+		static SemaphoreSlim taskLimit = new SemaphoreSlim(2);
+		private Queue<string> updateQueue = new Queue<string>();
 
 		private YahooAuctionsItem selectedItem {
 			get {
@@ -104,7 +97,6 @@ namespace Buypeeb {
 			this.builder = builder;
 			builder.Autoconnect(this);
 
-			this.statusLabel = (Label)builder.GetObject("LabelStatus");
 			this.selectionViewBox = (Box)builder.GetObject("SelectionViewBox");
 			this.endingLabel = (Label)builder.GetObject("LabelSelectedEnding");
 
@@ -115,6 +107,7 @@ namespace Buypeeb {
 
 			this.itemTreeView.Model = this.items;
 			TreeCellDataFunc[] funcs = {
+				new TreeCellDataFunc(this.RenderColumnFavourite),
 				new TreeCellDataFunc(this.RenderColumnName),
 				new TreeCellDataFunc(this.RenderColumnPriceYen),
 				new TreeCellDataFunc(this.RenderColumnPriceAUD),
@@ -140,10 +133,6 @@ namespace Buypeeb {
 
 		// general behaviour
 
-		private void SetStatus(string status) {
-			this.statusLabel.Text = status ?? "Buypeeb";
-		}
-
 		private (TreePath path, TreeIter iter) GetRow(string id) {
 			// TODO: surely there's a better way to do this
 			TreeIter iter;
@@ -179,7 +168,7 @@ namespace Buypeeb {
 
 		private void UpdateThread(string id) {
 			var item = this.settings.watchlist[id];
-			Console.WriteLine($"Updating {id}...");
+			// Console.WriteLine($"Updating {id}...");
 			// set item.ready to false to show that it's still being updated
 			// this changes a few behaviours, such as displaying the price as "..." instead of whatever's currently stored
 			item.ready = false;
@@ -206,17 +195,31 @@ namespace Buypeeb {
 			});
 
 			item.ready = true;
-			Console.WriteLine($"{id} updated.");
+			// Console.WriteLine($"{id} updated.");
 		}
 
-		private void UpdateItem(string id, bool force = false) {
+		private void ProcessUpdateQueue() {
-			// don't start a new task if there are more than [tasklimit] tasks currently running
+			// recursively process the updatequeue
-			// this makes sure we don't make 1000 simultaneous requests to yahoo auctions if there are 1000 items on the watchlist
+			// this is a BLOCKING FUNCTION
-			if (this.settings.watchlist[id].updatedRecently && !force) {
+			this.queueActive = true;
+			this.UpdateItem(this.updateQueue.Dequeue());
+			if (this.updateQueue.TryPeek(out string _)) {
+				this.ProcessUpdateQueue();
+			}
+			else {
+				this.queueActive = false;
+			}
+		}
+
+		private void UpdateItem(string id, bool evenIfAlreadyUpdating = false, bool force = false) {
+			var item = this.settings.watchlist[id];
+			if (item.updatedRecently && !force) {
 				// the item has been updated recently, and force is not true
 				return;
 			}
 
+			// don't start a new task if there are more than `tasklimit` tasks currently running
+			// this makes sure we don't make 1000 simultaneous requests to yahoo auctions if there are 1000 items on the watchlist
 			taskLimit.Wait();
 			var t = Task.Factory.StartNew(() => {
 				this.UpdateThread(id);
@@ -224,12 +227,28 @@ namespace Buypeeb {
 		}
 
 		private void UpdateItems() {
-			this.selectionViewBox.Sensitive = false;
+			if (this.queueActive) {
-
+				return;
-			var t = Task.Factory.StartNew(() => {
-				foreach (var item in this.settings.watchlist) {
-					this.UpdateItem(item.Key);
 			}
+
+			this.selectionViewBox.Sensitive = false;
+			foreach (var item in this.settings.watchlist) {
+				if (!this.updateQueue.Contains(item.Key)) {
+					// set everything to not ready first
+					// ensures other actions don't attempt to display the items even if UpdateItem hasn't started yet
+					item.Value.ready = false;
+					this.updateQueue.Enqueue(item.Key);
+				}
+			}
+
+			if (!this.updateQueue.TryPeek(out string _)) {
+				// queue is empty
+				return;
+			}
+
+			this.itemTreeView.QueueDraw();
+			var t = Task.Factory.StartNew(() => {
+				this.ProcessUpdateQueue();
 			});
 
 		}
@@ -444,12 +463,20 @@ namespace Buypeeb {
 
 		private void ButtonSelectedUpdateClicked(object sender, EventArgs args) {
 			this.selectionViewBox.Sensitive = false;
+			if (this.updateQueue.Contains(this.selectedItem.id)) {
+				// the item is already waiting to be updated
+				return;
+			}
 			this.UpdateItem(this.selectedItem.id);
 		}
 
 		private void ButtonSelectedFavouriteToggled(object sender, EventArgs args) {
 			ToggleButton s = (ToggleButton)sender;
 			this.selectedItem.favourite = s.Active;
+
+			// i don't know why this is necessary
+			var pathAndIter = this.GetRow(this.selectedItem.id);
+			this.items.EmitRowChanged(pathAndIter.path, pathAndIter.iter);
 		}
 
 		// timers
@@ -488,6 +515,11 @@ namespace Buypeeb {
 
 		// column renderers
 
+		private void RenderColumnFavourite(Gtk.TreeViewColumn column, Gtk.CellRenderer cell, Gtk.ITreeModel model, Gtk.TreeIter iter) {
+			YahooAuctionsItem item = (YahooAuctionsItem)model.GetValue(iter, 0);
+			(cell as Gtk.CellRendererText).Text = item.favourite ? "♥" : "";
+		}
+
 		private void RenderColumnName(Gtk.TreeViewColumn column, Gtk.CellRenderer cell, Gtk.ITreeModel model, Gtk.TreeIter iter) {
 			YahooAuctionsItem item = (YahooAuctionsItem)model.GetValue(iter, 0);
 			(cell as Gtk.CellRendererText).Text = item.name ?? "Loading...";

YahooAuctionsItem.cs

@@ -50,7 +50,6 @@ namespace Buypeeb {
 		public YahooAuctionsItem(string id, string name) {
 			this.id = id;
 			this.name = name;
-			this.ready = false;
 		}
 
 		public YahooAuctionsItem() {

ui/main.glade

@@ -1,14 +1,11 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<!-- Generated with glade 3.22.2 -->
+<!-- Generated with glade 3.36.0 -->
 <interface>
   <requires lib="gtk+" version="3.22"/>
   <object class="GtkTextBuffer" id="TextBufferSelectedNotes"/>
   <object class="GtkWindow" id="wndMain">
     <property name="can_focus">False</property>
-    <property name="default_width">700</property>
+    <property name="default_width">810</property>
-    <child type="titlebar">
-      <placeholder/>
-    </child>
     <child>
       <object class="GtkBox">
         <property name="visible">True</property>
@@ -115,7 +112,6 @@
                     <child>
                       <object class="GtkToolButton" id="ButtonClearEnded">
                         <property name="visible">True</property>
-                        <property name="sensitive">True</property>
                         <property name="can_focus">False</property>
                         <property name="tooltip_text" translatable="yes">Clear ended</property>
                         <property name="label" translatable="yes">Clear ended</property>
@@ -172,7 +168,6 @@
                     <child>
                       <object class="GtkToolButton">
                         <property name="visible">True</property>
-                        <property name="sensitive">True</property>
                         <property name="can_focus">False</property>
                         <property name="tooltip_text" translatable="yes">Save</property>
                         <property name="label" translatable="yes">Save</property>
@@ -287,11 +282,19 @@
                             <signal name="changed" handler="TreeViewItemsSelectionChanged" swapped="no"/>
                           </object>
                         </child>
+                        <child>
+                          <object class="GtkTreeViewColumn">
+                            <property name="title" translatable="yes">♥</property>
+                            <child>
+                              <object class="GtkCellRendererText"/>
+                            </child>
+                          </object>
+                        </child>
                         <child>
                           <object class="GtkTreeViewColumn">
                             <property name="resizable">True</property>
                             <property name="sizing">fixed</property>
-                            <property name="fixed_width">50</property>
+                            <property name="fixed_width">100</property>
                             <property name="title" translatable="yes">Name</property>
                             <property name="expand">True</property>
                             <property name="clickable">True</property>
@@ -807,47 +810,10 @@
             <property name="position">1</property>
           </packing>
         </child>
-        <child>
-          <object class="GtkBox">
-            <property name="visible">True</property>
-            <property name="can_focus">False</property>
-            <property name="margin_start">5</property>
-            <property name="margin_end">5</property>
-            <property name="margin_top">3</property>
-            <property name="margin_bottom">3</property>
-            <child>
-              <object class="GtkLabel" id="LabelStatus">
-                <property name="visible">True</property>
-                <property name="can_focus">False</property>
-                <property name="halign">start</property>
-                <property name="hexpand">True</property>
-                <property name="label" translatable="yes">Tracking 3 items</property>
       </object>
-              <packing>
-                <property name="expand">False</property>
-                <property name="fill">True</property>
-                <property name="position">0</property>
-              </packing>
     </child>
-            <child>
+    <child type="titlebar">
-              <object class="GtkSpinner">
+      <placeholder/>
-                <property name="visible">True</property>
-                <property name="can_focus">False</property>
-              </object>
-              <packing>
-                <property name="expand">False</property>
-                <property name="fill">True</property>
-                <property name="position">1</property>
-              </packing>
-            </child>
-          </object>
-          <packing>
-            <property name="expand">False</property>
-            <property name="fill">True</property>
-            <property name="position">2</property>
-          </packing>
-        </child>
-      </object>
     </child>
   </object>
 </interface>