Implement changing update channels

Allow the user to select which update channel they would like to
download updates from.

MultiMC.cpp

@@ -352,8 +352,10 @@ void MultiMC::initGlobalSettings()
 {
 	m_settings.reset(new INISettingsObject("multimc.cfg", this));
 	// Updates
-	m_settings->registerSetting("UseDevBuilds", false);
+	m_settings->registerSetting("UpdateChannel", version().channel);
 	m_settings->registerSetting("AutoUpdate", true);
+	
+	// Notifications
 	m_settings->registerSetting("ShownNotifications", QString());
 
 	// FTB

gui/dialogs/SettingsDialog.cpp

@@ -27,6 +27,8 @@
 #include "logic/lists/JavaVersionList.h"
 #include <logic/JavaChecker.h>
 
+#include "logic/updater/UpdateChecker.h"
+
 #include <settingsobject.h>
 #include <pathutils.h>
 #include <QFileDialog>
@@ -48,6 +50,17 @@ SettingsDialog::SettingsDialog(QWidget *parent) : QDialog(parent), ui(new Ui::Se
 
 	loadSettings(MMC->settings().get());
 	updateCheckboxStuff();
+
+	QObject::connect(MMC->updateChecker().get(), &UpdateChecker::channelListLoaded, this, &SettingsDialog::refreshUpdateChannelList);
+
+	if (MMC->updateChecker()->hasChannels())
+	{
+		refreshUpdateChannelList();
+	}
+	else
+	{
+		MMC->updateChecker()->updateChanList();
+	}
 }
 
 SettingsDialog::~SettingsDialog()
@@ -197,30 +210,72 @@ void SettingsDialog::on_buttonBox_rejected()
 	MMC->settings()->set("SettingsGeometry", saveGeometry().toBase64());
 }
 
-void SettingsDialog::applySettings(SettingsObject *s)
+void SettingsDialog::refreshUpdateChannelList()
 {
-	// Special cases
+	// Stop listening for selection changes. It's going to change a lot while we update it and we don't need to update the
+	// description label constantly.
+	QObject::disconnect(ui->updateChannelComboBox, SIGNAL(currentIndexChanged(int)), this, SLOT(updateChannelSelectionChanged(int)));
 
-	// Warn about dev builds.
+	QList<UpdateChecker::ChannelListEntry> channelList = MMC->updateChecker()->getChannelList();
-	if (!ui->devBuildsCheckBox->isChecked())
+	ui->updateChannelComboBox->clear();
+	int selection = -1;
+	for (int i = 0; i < channelList.count(); i++)
 	{
-		s->set("UseDevBuilds", false);
+		UpdateChecker::ChannelListEntry entry = channelList.at(i);
-	}
+		
-	else if (!s->get("UseDevBuilds").toBool())
+		// When it comes to selection, we'll rely on the indexes of a channel entry being the same in the
-	{
+		// combo box as it is in the update checker's channel list.
-		auto response = CustomMessageBox::selectable(
+		// This probably isn't very safe, but the channel list doesn't change often enough (or at all) for
-			this, tr("Development builds"),
+		// this to be a big deal. Hope it doesn't break...
-			tr("Development builds contain experimental features "
+		ui->updateChannelComboBox->addItem(entry.name);
-			   "and may be unstable. Are you sure you want to enable them?"),
+
-			QMessageBox::Question, QMessageBox::Yes | QMessageBox::No)->exec();
+		// If the update channel we just added was the selected one, set the current index in the combo box to it.
-		if (response == QMessageBox::Yes)
+		if (entry.id == m_currentUpdateChannel)
 		{
-			s->set("UseDevBuilds", true);
+			QLOG_DEBUG() << "Selected index" << i << "channel id" << m_currentUpdateChannel;
+			selection = i;
 		}
 	}
+	
+	ui->updateChannelComboBox->setCurrentIndex(selection);
 
+	// Start listening for selection changes again and update the description label.
+	QObject::connect(ui->updateChannelComboBox, SIGNAL(currentIndexChanged(int)), this, SLOT(updateChannelSelectionChanged(int)));
+	refreshUpdateChannelDesc();
+
+	// Now that we've updated the channel list, we can enable the combo box.
+	// It starts off disabled so that if the channel list hasn't been loaded, it will be disabled.
+	ui->updateChannelComboBox->setEnabled(true);
+}
+
+void SettingsDialog::updateChannelSelectionChanged(int index)
+{
+	refreshUpdateChannelDesc();
+}
+
+void SettingsDialog::refreshUpdateChannelDesc()
+{
+	// Get the channel list.
+	QList<UpdateChecker::ChannelListEntry> channelList = MMC->updateChecker()->getChannelList();
+	int selectedIndex = ui->updateChannelComboBox->currentIndex();
+	if (selectedIndex < channelList.count())
+	{
+		// Find the channel list entry with the given index.
+		UpdateChecker::ChannelListEntry selected = channelList.at(selectedIndex);
+
+		// Set the description text.
+		ui->updateChannelDescLabel->setText(selected.description);
+
+		// Set the currently selected channel ID.
+		m_currentUpdateChannel = selected.id;
+	}
+}
+
+void SettingsDialog::applySettings(SettingsObject *s)
+{
 	// Updates
 	s->set("AutoUpdate", ui->autoUpdateCheckBox->isChecked());
+	s->set("UpdateChannel", m_currentUpdateChannel);
 
 	// FTB
 	s->set("TrackFTBInstances", ui->trackFtbBox->isChecked());
@@ -288,7 +343,7 @@ void SettingsDialog::loadSettings(SettingsObject *s)
 {
 	// Updates
 	ui->autoUpdateCheckBox->setChecked(s->get("AutoUpdate").toBool());
-	ui->devBuildsCheckBox->setChecked(s->get("UseDevBuilds").toBool());
+	m_currentUpdateChannel = s->get("UpdateChannel").toString();
 
 	// FTB
 	ui->trackFtbBox->setChecked(s->get("TrackFTBInstances").toBool());
@@ -392,3 +447,4 @@ void SettingsDialog::checkFinished(JavaCheckResult result)
 			   "or set the path to the java executable."));
 	}
 }
+

gui/dialogs/SettingsDialog.h

@@ -74,7 +74,25 @@ slots:
 	void on_javaBrowseBtn_clicked();
 
 	void checkFinished(JavaCheckResult result);
+
+	/*!
+	 * Updates the list of update channels in the combo box.
+	 */
+	void refreshUpdateChannelList();
+
+	/*!
+	 * Updates the channel description label.
+	 */
+	void refreshUpdateChannelDesc();
+
+    void updateChannelSelectionChanged(int index);
+
 private:
 	Ui::SettingsDialog *ui;
 	std::shared_ptr<JavaChecker> checker;
+
+	/*!
+	 * Stores the currently selected update channel.
+	 */
+	QString m_currentUpdateChannel;
 };

gui/dialogs/SettingsDialog.ui

@@ -7,7 +7,7 @@
     <x>0</x>
     <y>0</y>
     <width>526</width>
-    <height>628</height>
+    <height>639</height>
    </rect>
   </property>
   <property name="sizePolicy">
@@ -77,14 +77,7 @@
          <property name="title">
           <string>Update Settings</string>
          </property>
-         <layout class="QVBoxLayout" name="updateSettingsBoxLayout">
+         <layout class="QVBoxLayout" name="verticalLayout_7">
-          <item>
-           <widget class="QCheckBox" name="devBuildsCheckBox">
-            <property name="text">
-             <string>Use development builds?</string>
-            </property>
-           </widget>
-          </item>
           <item>
            <widget class="QCheckBox" name="autoUpdateCheckBox">
             <property name="text">
@@ -92,6 +85,31 @@
             </property>
            </widget>
           </item>
+          <item>
+           <layout class="QVBoxLayout" name="channelVerticalLayout">
+            <item>
+             <widget class="QLabel" name="updateChannelLabel">
+              <property name="text">
+               <string>Update Channel:</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QComboBox" name="updateChannelComboBox">
+              <property name="enabled">
+               <bool>false</bool>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QLabel" name="updateChannelDescLabel">
+              <property name="text">
+               <string>No channel selected.</string>
+              </property>
+             </widget>
+            </item>
+           </layout>
+          </item>
          </layout>
         </widget>
        </item>
@@ -644,11 +662,9 @@
   </layout>
  </widget>
  <tabstops>
-  <tabstop>settingsTab</tabstop>
   <tabstop>buttonBox</tabstop>
   <tabstop>sortLastLaunchedBtn</tabstop>
   <tabstop>sortByNameBtn</tabstop>
-  <tabstop>devBuildsCheckBox</tabstop>
   <tabstop>autoUpdateCheckBox</tabstop>
   <tabstop>instDirTextBox</tabstop>
   <tabstop>modsDirTextBox</tabstop>

logic/updater/UpdateChecker.cpp

@@ -24,6 +24,8 @@
 #include <QJsonArray>
 #include <QJsonValue>
 
+#include <settingsobject.h>
+
 #define API_VERSION 0
 #define CHANLIST_FORMAT 0
 
@@ -70,9 +72,8 @@ void UpdateChecker::checkForUpdate(bool notifyNoUpdate)
 
 	m_updateChecking = true;
 
-	// Get the URL for the channel we're using.
+	// Get the channel we're checking.
-	// TODO: Allow user to select channels. For now, we'll just use the current channel.
+	QString updateChannel = MMC->settings()->get("UpdateChannel").toString();
-	QString updateChannel = m_currentChannel;
 
 	// Find the desired channel within the channel list and get its repo URL. If if cannot be
 	// found, error.

logic/updater/UpdateChecker.h

@@ -54,7 +54,7 @@ public:
 	QList<ChannelListEntry> getChannelList() const;
 
 	/*!
-	 * Returns true if the channel list is empty.
+	 * Returns false if the channel list is empty.
 	 */
 	bool hasChannels() const;