Add update promoter network functions

forms/mainwindow.ui

@@ -1715,7 +1715,7 @@
                              <x>0</x>
                              <y>0</y>
                              <width>100</width>
-                             <height>30</height>
+                             <height>16</height>
                             </rect>
                            </property>
                            <property name="sizePolicy">
@@ -1809,7 +1809,7 @@
                              <x>0</x>
                              <y>0</y>
                              <width>100</width>
-                             <height>30</height>
+                             <height>16</height>
                             </rect>
                            </property>
                            <property name="sizePolicy">
@@ -1903,7 +1903,7 @@
                              <x>0</x>
                              <y>0</y>
                              <width>100</width>
-                             <height>30</height>
+                             <height>16</height>
                             </rect>
                            </property>
                            <property name="sizePolicy">
@@ -2003,7 +2003,7 @@
                              <x>0</x>
                              <y>0</y>
                              <width>100</width>
-                             <height>30</height>
+                             <height>16</height>
                             </rect>
                            </property>
                            <property name="sizePolicy">
@@ -2097,7 +2097,7 @@
                              <x>0</x>
                              <y>0</y>
                              <width>100</width>
-                             <height>30</height>
+                             <height>16</height>
                             </rect>
                            </property>
                            <property name="sizePolicy">
@@ -3112,6 +3112,7 @@
     <addaction name="actionAbout_Porymap"/>
     <addaction name="actionOpen_Log_File"/>
     <addaction name="actionOpen_Config_Folder"/>
+    <addaction name="actionCheck_for_Updates"/>
    </widget>
    <widget class="QMenu" name="menuOptions">
     <property name="title">
@@ -3406,6 +3407,14 @@
     <string>Custom Scripts...</string>
    </property>
   </action>
+  <action name="actionCheck_for_Updates">
+   <property name="text">
+    <string>Check for Updates...</string>
+   </property>
+   <property name="menuRole">
+    <enum>QAction::ApplicationSpecificRole</enum>
+   </property>
+  </action>
  </widget>
  <layoutdefault spacing="6" margin="11"/>
  <customwidgets>

include/mainwindow.h

@@ -12,6 +12,7 @@
 #include <QCloseEvent>
 #include <QAbstractItemModel>
 #include <QJSValue>
+#include <QNetworkAccessManager>
 #include "project.h"
 #include "orderedjson.h"
 #include "config.h"
@@ -288,6 +289,7 @@ private slots:
     void on_spinBox_SelectedCollision_valueChanged(int collision);
     void on_actionRegion_Map_Editor_triggered();
     void on_actionPreferences_triggered();
+    void on_actionCheck_for_Updates_triggered();
     void togglePreferenceSpecificUi();
     void on_actionProject_Settings_triggered();
     void on_actionCustom_Scripts_triggered();
@@ -296,6 +298,7 @@ private slots:
 public:
     Ui::MainWindow *ui;
     Editor *editor = nullptr;
+    QPointer<QNetworkAccessManager> networkAccessManager = nullptr;
 
 private:
     QLabel *label_MapRulerStatus = nullptr;
@@ -396,6 +399,8 @@ private:
     QObjectList shortcutableObjects() const;
     void addCustomHeaderValue(QString key, QJsonValue value, bool isNew = false);
     int insertTilesetLabel(QStringList * list, QString label);
+
+    void checkForUpdates();
 };
 
 enum MapListUserRoles {

porymap.pro

@@ -4,7 +4,7 @@
 #
 #-------------------------------------------------
 
-QT       += core gui qml
+QT       += core gui qml network
 
 greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
 

src/mainwindow.cpp

@@ -242,6 +242,63 @@ void MainWindow::initExtraSignals() {
     label_MapRulerStatus->setAlignment(Qt::AlignCenter);
     label_MapRulerStatus->setTextFormat(Qt::PlainText);
     label_MapRulerStatus->setTextInteractionFlags(Qt::TextSelectableByMouse);
+
+    // TODO: (if enabled) queue an automatic "Check for Updates"
+}
+
+// TODO: Relocate
+#include <QNetworkReply>
+#include <QNetworkRequest>
+void MainWindow::on_actionCheck_for_Updates_triggered() {
+    checkForUpdates();
+}
+
+void MainWindow::checkForUpdates() {
+    if (!this->networkAccessManager)
+        this->networkAccessManager = new QNetworkAccessManager(this);
+
+    // We could get ".../releases/latest" to retrieve less data, but this would run into problems if the
+    // most recent item on the releases page is not actually a new release (like the static windows build).
+    QNetworkRequest request(QUrl("https://api.github.com/repos/huderlem/porymap/releases"));
+    request.setHeader(QNetworkRequest::ContentTypeHeader, "application/json");
+
+    QNetworkReply * reply = this->networkAccessManager->get(request);
+
+    connect(reply, &QNetworkReply::finished, [this, reply] {
+        QJsonDocument data = QJsonDocument::fromJson(reply->readAll());
+        QJsonArray releases = data.array();
+
+        // Read all the items on the releases page, stopping when we find a tag that parses as a version identifier.
+        // Objects in the releases page data are sorted newest to oldest. Although I can't find a guarantee of this in
+        // GitHub's API documentation, this seems unlikely to change.
+        for (int i = 0; i < releases.size(); i++) {
+            auto release = releases.at(i).toObject();
+
+            const QStringList tag = release.value("tag_name").toString().split(".");
+            if (tag.length() != 3) continue;
+
+            bool ok;
+            int major = tag.at(0).toInt(&ok);
+            if (!ok) continue;
+            int minor = tag.at(1).toInt(&ok);
+            if (!ok) continue;
+            int patch = tag.at(2).toInt(&ok);
+            if (!ok) continue;
+
+            const QString downloadLink = release.value("html_url").toString();
+            if (downloadLink.isEmpty()) continue;
+
+            // We've found a valid release tag, we can stop reading.
+            logInfo(QString("Newest release is %1.%2.%3\n%4").arg(major).arg(minor).arg(patch).arg(downloadLink));
+
+            // If the release was published very recently it won't have a description yet, in which case don't tell the user.
+            const QString changelog = release.value("body").toString();
+            if (changelog.isEmpty()) break;
+
+            // TODO: Compare version to host version, then show appropriate dialog
+            break;
+        }
+    });
 }
 
 void MainWindow::initEditor() {