[ci skip] Add gradle task to quickly test/debug code changes

common/build.gradle

@@ -17,3 +17,33 @@ sourceSets {
         }
     }
 }
+
+// Task to quickly test/debug code changes using https://github.com/ViaVersion/ViaProxy
+// For further instructions see the ViaProxy repository README
+tasks.register("runViaProxy", JavaExec) {
+    dependsOn tasks.jar
+
+    def viaProxyConfiguration = configurations.create("viaProxy")
+    viaProxyConfiguration.dependencies.add(dependencies.create("net.raphimc:ViaProxy:3.3.5-SNAPSHOT") {
+        transitive = false
+    })
+
+    mainClass = "net.raphimc.viaproxy.ViaProxy"
+    classpath = viaProxyConfiguration
+    workingDir = file("run")
+    jvmArgs = ["-DskipUpdateCheck"]
+    if (System.getProperty("viaproxy.gui.autoStart") != null) {
+        jvmArgs("-Dviaproxy.gui.autoStart")
+    }
+
+    doFirst {
+        def jarsDir = file("$workingDir/jars")
+        jarsDir.mkdirs()
+        file("$jarsDir/${project.name}.jar").bytes = tasks.jar.archiveFile.get().asFile.bytes
+    }
+
+    doLast {
+        file("$workingDir/jars/${project.name}.jar").delete()
+        file("$workingDir/logs").deleteDir()
+    }
+}