Argument parsing rework (#1940)

* Experimental argument handling

* Restored browser extension launch functionality

Also moved check from BrowerExtension.cpp to Args.cpp as it is more relevant there and doesn't require passing arguments to a function in another file

* Fixed formatting

* Simplified Args.cpp code, added changelog entry

* Hid crash-recovery from help

* Dont save settings if launched with --channels

* Changed parsing method to t:channel

* Code cleanup

* Changed plaform delimeter to :, platform defaults to Twitch

Co-authored-by: fourtf <tf.four@gmail.com>

src/common/Args.cpp

@@ -1,27 +1,87 @@
 #include "Args.hpp"
 
+#include <QApplication>
+#include <QCommandLineParser>
+#include <QDebug>
+#include <QJsonArray>
+#include <QJsonDocument>
+#include <QJsonObject>
+#include <QStringList>
+
 namespace chatterino {
 
-Args::Args(const QStringList &args)
+Args::Args(const QApplication &app)
 {
-    for (auto &&arg : args)
+    QCommandLineParser parser;
+    parser.setApplicationDescription("Chatterino 2 Client for Twitch Chat");
+    parser.addHelpOption();
+
+    // Used internally by app to restart after unexpected crashes
+    QCommandLineOption crashRecoveryOption("crash-recovery");
+    crashRecoveryOption.setHidden(true);
+
+    parser.addOptions({
+        {{"v", "version"}, "Displays version information."},
+        crashRecoveryOption,
+    });
+    parser.addOption(QCommandLineOption(
+        {"c", "channels"},
+        "Joins only supplied channels on startup. Use letters with colons to "
+        "specify platform. Only twitch channels are supported at the moment.\n"
+        "If platform isn't specified, default is Twitch.",
+        "t:channel1;t:channel2;..."));
+    parser.process(app);
+
+    const QStringList args = parser.positionalArguments();
+    this->shouldRunBrowserExtensionHost =
+        (args.size() > 0 && (args[0].startsWith("chrome-extension://") ||
+                             args[0].endsWith(".json")));
+
+    if (parser.isSet("c"))
     {
-        if (arg == "--crash-recovery")
+        QJsonArray channelArray;
+        QStringList channelArgList = parser.value("c").split(";");
+        for (QString channelArg : channelArgList)
         {
-            this->crashRecovery = true;
+            // Twitch is default platform
+            QString platform = "t";
+            QString channelName = channelArg;
+
+            const QRegExp regExp("(.):(.*)");
+            if (regExp.indexIn(channelArg) != -1)
+            {
+                platform = regExp.cap(1);
+                channelName = regExp.cap(2);
+            }
+
+            // Twitch (default)
+            if (platform == "t")
+            {
+                // TODO: try not to parse JSON
+                QString channelObjectString =
+                    "{\"splits2\": { \"data\": { \"name\": \"" + channelName +
+                    "\", \"type\": \"twitch\" }, \"type\": \"split\" }}";
+                channelArray.push_back(
+                    QJsonDocument::fromJson(channelObjectString.toUtf8())
+                        .object());
+            }
         }
-        else if (arg == "--version")
+        if (channelArray.size() > 0)
         {
-            this->printVersion = true;
+            this->dontSaveSettings = true;
+            this->channelsToJoin = channelArray;
         }
     }
+
+    this->printVersion = parser.isSet("v");
+    this->crashRecovery = parser.isSet("crash-recovery");
 }
 
 static Args *instance = nullptr;
 
-void initArgs(const QStringList &args)
+void initArgs(const QApplication &app)
 {
-    instance = new Args(args);
+    instance = new Args(app);
 }
 
 const Args &getArgs()