refactor: improve partner customization

app/src/main/java/im/angry/openeuicc/util/Partner.kt

@@ -11,23 +11,28 @@ class Partner {
     companion object {
         private const val ACTION = "com.google.android.euicc.action.PARTNER_CUSTOMIZATION"
 
-        fun getInstance(context: Context, action: String = ACTION): Partner? {
+        private val instances = mutableMapOf<String, Partner?>()
-            var flags = if (BuildConfig.DEBUG)
+
+        private val packageFlags: Int
+            get() {
+                val flags = if (BuildConfig.DEBUG)
                     PackageManager.MATCH_UNINSTALLED_PACKAGES else
                     PackageManager.MATCH_SYSTEM_ONLY
-            flags = flags or PackageManager.MATCH_DISABLED_COMPONENTS
+                return flags or PackageManager.MATCH_DISABLED_COMPONENTS
-            val apps = context.packageManager
+            }
-                .queryBroadcastReceivers(Intent(action), flags)
+
+        fun getInstance(context: Context, action: String = ACTION) = instances.getOrPut(action) {
+            context.packageManager
+                .queryBroadcastReceivers(Intent(action), packageFlags)
                 .mapNotNull { it.activityInfo?.applicationInfo }
-            for (app in apps) {
+                .firstNotNullOfOrNull {
                     try {
-                    val resources = context.packageManager.getResourcesForApplication(app)
+                        context.packageManager.getResourcesForApplication(it)
-                    return Partner(resources)
                     } catch (_: PackageManager.NameNotFoundException) {
-                    continue
+                        null
                     }
                 }
-            return null
+                ?.let(::Partner)
         }
     }