ci: add optional release signing from repository secrets

.gitea/workflows/android-build.yml

@@ -53,6 +53,39 @@ jobs:
             "platforms;android-35" \
             "build-tools;35.0.0"
 
+      - name: Prepare optional release signing
+        if: github.event_name == 'release'
+        env:
+          ANDROID_KEYSTORE_BASE64: ${{ secrets.ANDROID_KEYSTORE_BASE64 }}
+          ANDROID_KEYSTORE_PASSWORD: ${{ secrets.ANDROID_KEYSTORE_PASSWORD }}
+          ANDROID_KEY_ALIAS: ${{ secrets.ANDROID_KEY_ALIAS }}
+          ANDROID_KEY_PASSWORD: ${{ secrets.ANDROID_KEY_PASSWORD }}
+        shell: bash
+        run: |
+          set -euo pipefail
+          missing=()
+          for key in ANDROID_KEYSTORE_BASE64 ANDROID_KEYSTORE_PASSWORD ANDROID_KEY_ALIAS ANDROID_KEY_PASSWORD; do
+            if [ -z "${!key:-}" ]; then
+              missing+=("$key")
+            fi
+          done
+
+          if [ ${#missing[@]} -gt 0 ]; then
+            printf -v missing_csv '%s, ' "${missing[@]}"
+            missing_csv="${missing_csv%, }"
+            echo "::warning::Release signing secrets missing: ${missing_csv}. Building unsigned/default-signed release AAB."
+            exit 0
+          fi
+
+          mkdir -p .ci-secrets
+          printf '%s' "$ANDROID_KEYSTORE_BASE64" | base64 -d > .ci-secrets/release-keystore.jks
+          cat > keystore.properties <<EOF
+          storeFile=.ci-secrets/release-keystore.jks
+          storePassword=$ANDROID_KEYSTORE_PASSWORD
+          keyAlias=$ANDROID_KEY_ALIAS
+          keyPassword=$ANDROID_KEY_PASSWORD
+          EOF
+
       - name: Make Gradle wrapper executable
         run: chmod +x gradlew
 

app/build.gradle.kts

@@ -1,9 +1,23 @@
+import java.util.Properties
+
 plugins {
     id("com.android.application")
     id("org.jetbrains.kotlin.android")
     id("org.jetbrains.kotlin.plugin.compose")
 }
 
+val keystorePropertiesFile = rootProject.file("keystore.properties")
+val keystoreProperties = Properties()
+if (keystorePropertiesFile.exists()) {
+    keystorePropertiesFile.inputStream().use { keystoreProperties.load(it) }
+}
+val hasReleaseSigning = listOf(
+    "storeFile",
+    "storePassword",
+    "keyAlias",
+    "keyPassword",
+).all { !keystoreProperties.getProperty(it).isNullOrBlank() }
+
 android {
     namespace = "solutions.tretter.esunandroid"
     compileSdk = 35
@@ -19,6 +33,17 @@ android {
         vectorDrawables.useSupportLibrary = true
     }
 
+    signingConfigs {
+        if (hasReleaseSigning) {
+            create("release") {
+                storeFile = file(keystoreProperties.getProperty("storeFile"))
+                storePassword = keystoreProperties.getProperty("storePassword")
+                keyAlias = keystoreProperties.getProperty("keyAlias")
+                keyPassword = keystoreProperties.getProperty("keyPassword")
+            }
+        }
+    }
+
     buildTypes {
         release {
             isMinifyEnabled = false
@@ -26,6 +51,9 @@ android {
                 getDefaultProguardFile("proguard-android-optimize.txt"),
                 "proguard-rules.pro"
             )
+            if (hasReleaseSigning) {
+                signingConfig = signingConfigs.getByName("release")
+            }
         }
     }