build(android): add fdroid distribution flavor

android/app/build.gradle

@@ -1,5 +1,30 @@
 apply plugin: 'com.android.application'
 
+import groovy.json.JsonSlurper
+
+def resolvePackageVersionName() {
+    def packageJsonFile = file("../../package.json")
+    if (!packageJsonFile.exists()) {
+        return "1.0"
+    }
+
+    return new JsonSlurper().parse(packageJsonFile).version.toString()
+}
+
+def versionNameToCode(String versionName) {
+    def stableVersion = versionName.replaceFirst(/^v/, "").split("-")[0]
+    def parts = stableVersion.tokenize(".").collect { part -> part.isInteger() ? part.toInteger() : 0 }
+
+    while (parts.size() < 3) {
+        parts.add(0)
+    }
+
+    return (parts[0] * 10000) + (parts[1] * 100) + parts[2]
+}
+
+def resolvedVersionName = "${project.findProperty("APP_VERSION_NAME") ?: resolvePackageVersionName()}"
+def resolvedVersionCode = Integer.parseInt("${project.findProperty("APP_VERSION_CODE") ?: versionNameToCode(resolvedVersionName)}")
+
 android {
     namespace "fivechan.android"
     compileSdkVersion rootProject.ext.compileSdkVersion
@@ -7,8 +32,8 @@ android {
         applicationId "fivechan.android"
         minSdkVersion rootProject.ext.minSdkVersion
         targetSdkVersion rootProject.ext.targetSdkVersion
-        versionCode Integer.parseInt(project.findProperty("APP_VERSION_CODE") ?: "1")
-        versionName "${project.findProperty("APP_VERSION_NAME") ?: "1.0"}"
+        versionCode resolvedVersionCode
+        versionName resolvedVersionName
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
         aaptOptions {
              // Files and dirs to omit from the packaged assets dir, modified to accommodate modern web apps.
@@ -16,6 +41,15 @@ android {
             ignoreAssetsPattern '!.svn:!.git:!.ds_store:!*.scc:.*:!CVS:!thumbs.db:!picasa.ini:!*~'
         }
     }
+    flavorDimensions "distribution"
+    productFlavors {
+        github {
+            dimension "distribution"
+        }
+        fdroid {
+            dimension "distribution"
+        }
+    }
     buildTypes {
         release {
             minifyEnabled false

android/app/src/fdroid/java/fivechan/android/MainActivity.java

@@ -0,0 +1,15 @@
+package fivechan.android;
+
+import android.os.Bundle;
+import com.capacitorjs.plugins.statusbar.StatusBarPlugin;
+import com.getcapacitor.BridgeActivity;
+
+public class MainActivity extends BridgeActivity {
+    @Override
+    public void onCreate(Bundle savedInstanceState) {
+        // Custom plugins must be registered before bridge initialization.
+        registerPlugin(FileUploaderPlugin.class);
+        registerPlugin(StatusBarPlugin.class);
+        super.onCreate(savedInstanceState);
+    }
+}

android/app/src/github/AndroidManifest.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES" />
+</manifest>

android/app/src/github/java/fivechan/android/MainActivity.java

@@ -1,8 +1,8 @@
 package fivechan.android;
 
 import android.os.Bundle;
-import com.getcapacitor.BridgeActivity;
 import com.capacitorjs.plugins.statusbar.StatusBarPlugin;
+import com.getcapacitor.BridgeActivity;
 
 public class MainActivity extends BridgeActivity {
     @Override

android/app/src/main/AndroidManifest.xml

@@ -2,7 +2,6 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android">
     <uses-permission android:name="android.permission.INTERNET" />
     <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
-    <uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES" />
 
     <application
         android:allowBackup="true"