Refactor Kotlin code to improve error handling

android/src/main/java/com/bitmovin/player/reactnative/BitmovinBaseModule.kt

@@ -1,6 +1,7 @@
 package com.bitmovin.player.reactnative
 
 import com.bitmovin.player.api.Player
+import com.bitmovin.player.api.source.Source
 import com.bitmovin.player.reactnative.extensions.drmModule
 import com.bitmovin.player.reactnative.extensions.offlineModule
 import com.bitmovin.player.reactnative.extensions.playerModule
@@ -22,13 +23,11 @@ import com.facebook.react.uimanager.UIManagerModule
 abstract class BitmovinBaseModule(
     protected val context: ReactApplicationContext,
 ) : ReactContextBaseJavaModule(context) {
-    /** [resolve] the [Promise] by running [block] in the UI thread with [UIManagerModule.addUIBlock].  */
-    protected inline fun <T> Promise.resolveOnUIThread(crossinline block: RejectPromiseOnExceptionBlock.() -> T) {
+    /** [resolve] the [TPromise] by running [block] in the UI thread with [UIManagerModule.addUIBlock].  */
+    protected inline fun <T, R : T> TPromise<T>.resolveOnUiThread(crossinline block: RejectPromiseOnExceptionBlock.() -> R) {
         val uiManager = runAndRejectOnException { uiManager } ?: return
         uiManager.addUIBlock {
-            resolveOnCurrentThread {
-                resolve(block())
-            }
+            resolveOnCurrentThread{ block() }
         }
     }
 
@@ -47,25 +46,48 @@ abstract class BitmovinBaseModule(
     protected val RejectPromiseOnExceptionBlock.drmModule: DrmModule get() = context.drmModule
         ?: throw IllegalStateException("DrmModule not found")
 
-    fun RejectPromiseOnExceptionBlock.getPlayer(nativeId: NativeId): Player = playerModule.getPlayerOrNull(nativeId)
-        ?: throw IllegalArgumentException("Invalid PlayerId")
+    fun RejectPromiseOnExceptionBlock.getPlayer(
+        nativeId: NativeId,
+        playerModule: PlayerModule = this.playerModule
+    ): Player = playerModule.getPlayerOrNull(nativeId) ?: throw IllegalArgumentException("Invalid PlayerId")
+
+    fun RejectPromiseOnExceptionBlock.getSource(
+        nativeId: NativeId,
+        sourceModule: SourceModule = this.sourceModule
+    ): Source = sourceModule.getSourceOrNull(nativeId) ?: throw IllegalArgumentException("Invalid SourceId")
 }
 
 /** Run [block], forwarding the return value. If it throws, sets [Promise.reject] and return null. */
-inline fun <T> Promise.runAndRejectOnException(block: RejectPromiseOnExceptionBlock.() -> T): T? = try {
+inline fun <T, R> TPromise<T>.runAndRejectOnException(block: RejectPromiseOnExceptionBlock.() -> R): R? = try {
     RejectPromiseOnExceptionBlock.block()
 } catch (e: Exception) {
     reject(e)
     null
 }
 
 /** Resolve the [Promise] with the value returned by [block]. If it throws, sets [Promise.reject]. */
-inline fun <T> Promise.resolveOnCurrentThread(block: RejectPromiseOnExceptionBlock.() -> T): Unit = try {
-    // Promise only support built-in types. Functions that return [Unit] must resolve to `null`.
-    resolve(RejectPromiseOnExceptionBlock.block().takeUnless { it is Unit })
+inline fun <T> TPromise<T>.resolveOnCurrentThread(crossinline block: RejectPromiseOnExceptionBlock.() -> T): Unit = try {
+    resolve(RejectPromiseOnExceptionBlock.block())
 } catch (e: Exception) {
     reject(e)
 }
 
 /** Receiver of code that can safely throw when resolving a [Promise]. */
 object RejectPromiseOnExceptionBlock
+
+/** Compile time wrapper for Promises to type check the resolved type [T]. */
+@JvmInline
+value class TPromise<T>(val promise: Promise) {
+    // Promise only support built-in types. Functions that return [Unit] must resolve to `null`.
+    fun resolve(value: T): Unit = promise.resolve(value.takeUnless { it is Unit })
+    fun reject(throwable: Throwable) = promise.reject(throwable)
+}
+val Promise.int get() = TPromise<Int>(this)
+val Promise.unit get() = TPromise<Unit>(this)
+val Promise.string get() = TPromise<String>(this)
+val Promise.double get() = TPromise<Double>(this)
+val Promise.float get() = TPromise<Float>(this)
+val Promise.bool get() = TPromise<Boolean>(this)
+val Promise.map get() = TPromise<ReadableMap>(this)
+val Promise.array get() = TPromise<ReadableArray>(this)
+val <T> TPromise<T>.nullable get() = TPromise<T?>(promise)

android/src/main/java/com/bitmovin/player/reactnative/BitmovinCastManagerModule.kt

@@ -18,15 +18,15 @@ class BitmovinCastManagerModule(context: ReactApplicationContext) : BitmovinBase
      * Returns whether the [BitmovinCastManager] is initialized.
      */
     @ReactMethod
-    fun isInitialized(promise: Promise) = promise.resolveOnUIThread {
+    fun isInitialized(promise: Promise) = promise.unit.resolveOnUiThread {
         BitmovinCastManager.isInitialized()
     }
 
     /**
      * Initializes the [BitmovinCastManager] with the given options.
      */
     @ReactMethod
-    fun initializeCastManager(options: ReadableMap?, promise: Promise) = promise.resolveOnUIThread {
+    fun initializeCastManager(options: ReadableMap?, promise: Promise) = promise.unit.resolveOnUiThread {
         val castOptions = options?.toCastOptions()
         BitmovinCastManager.initialize(
             castOptions?.applicationId,
@@ -38,15 +38,15 @@ class BitmovinCastManagerModule(context: ReactApplicationContext) : BitmovinBase
      * Sends a message to the receiver.
      */
     @ReactMethod
-    fun sendMessage(message: String, messageNamespace: String?, promise: Promise) = promise.resolveOnUIThread {
+    fun sendMessage(message: String, messageNamespace: String?, promise: Promise) = promise.unit.resolveOnUiThread {
         BitmovinCastManager.getInstance().sendMessage(message, messageNamespace)
     }
 
     /**
      * Updates the context of the [BitmovinCastManager] to the current activity.
      */
     @ReactMethod
-    fun updateContext(promise: Promise) = promise.resolveOnUIThread {
+    fun updateContext(promise: Promise) = promise.unit.resolveOnUiThread {
         BitmovinCastManager.getInstance().updateContext(currentActivity)
     }
 }

android/src/main/java/com/bitmovin/player/reactnative/BufferModule.kt

@@ -22,7 +22,7 @@ class BufferModule(context: ReactApplicationContext) : BitmovinBaseModule(contex
      */
     @ReactMethod
     fun getLevel(nativeId: NativeId, type: String, promise: Promise) {
-        promise.resolveOnUIThread {
+        promise.map.resolveOnUiThread {
             val player = getPlayer(nativeId)
             val bufferType = type.toBufferTypeOrThrow()
             RNBufferLevels(
@@ -40,7 +40,7 @@ class BufferModule(context: ReactApplicationContext) : BitmovinBaseModule(contex
      */
     @ReactMethod
     fun setTargetLevel(nativeId: NativeId, type: String, value: Double, promise: Promise) {
-        promise.resolveOnUIThread {
+        promise.unit.resolveOnUiThread {
             getPlayer(nativeId).buffer.setTargetLevel(type.toBufferTypeOrThrow(), value)
         }
     }

android/src/main/java/com/bitmovin/player/reactnative/DrmModule.kt

@@ -75,7 +75,7 @@ class DrmModule(context: ReactApplicationContext) : BitmovinBaseModule(context)
      */
     @ReactMethod
     fun initWithConfig(nativeId: NativeId, config: ReadableMap, promise: Promise) {
-        promise.resolveOnUIThread {
+        promise.unit.resolveOnUiThread {
             if (drmConfigs.containsKey(nativeId)) {
                 throw InvalidParameterException("NativeId already exists $nativeId")
             }

android/src/main/java/com/bitmovin/player/reactnative/OfflineModule.kt

@@ -60,7 +60,7 @@ class OfflineModule(context: ReactApplicationContext) : BitmovinBaseModule(conte
      */
     @ReactMethod
     fun initWithConfig(nativeId: NativeId, config: ReadableMap?, drmNativeId: NativeId?, promise: Promise) {
-        promise.resolveOnUIThread {
+        promise.unit.resolveOnUiThread {
             if (offlineContentManagerBridges.containsKey(nativeId)) {
                 throw InvalidParameterException("content manager bridge id already exists: $nativeId")
             }
@@ -84,7 +84,7 @@ class OfflineModule(context: ReactApplicationContext) : BitmovinBaseModule(conte
 
     @ReactMethod
     fun getState(nativeId: NativeId, promise: Promise) {
-        promise.resolveWithBridge(nativeId) {
+        promise.string.resolveWithBridge(nativeId) {
             state.name
         }
     }
@@ -96,7 +96,7 @@ class OfflineModule(context: ReactApplicationContext) : BitmovinBaseModule(conte
      */
     @ReactMethod
     fun getOptions(nativeId: NativeId, promise: Promise) {
-        promise.resolveWithBridge(nativeId) {
+        promise.unit.resolveWithBridge(nativeId) {
             getOptions()
         }
     }
@@ -110,7 +110,7 @@ class OfflineModule(context: ReactApplicationContext) : BitmovinBaseModule(conte
      */
     @ReactMethod
     fun download(nativeId: NativeId, request: ReadableMap, promise: Promise) {
-        promise.resolveWithBridge(nativeId) {
+        promise.unit.resolveWithBridge(nativeId) {
             when (state) {
                 OfflineOptionEntryState.Downloaded -> throw IllegalStateException("Download already completed")
                 OfflineOptionEntryState.Downloading, OfflineOptionEntryState.Failed -> throw IllegalStateException(
@@ -135,7 +135,7 @@ class OfflineModule(context: ReactApplicationContext) : BitmovinBaseModule(conte
      */
     @ReactMethod
     fun resume(nativeId: NativeId, promise: Promise) {
-        promise.resolveWithBridge(nativeId) {
+        promise.unit.resolveWithBridge(nativeId) {
             resume()
         }
     }
@@ -146,7 +146,7 @@ class OfflineModule(context: ReactApplicationContext) : BitmovinBaseModule(conte
      */
     @ReactMethod
     fun suspend(nativeId: NativeId, promise: Promise) {
-        promise.resolveWithBridge(nativeId) {
+        promise.unit.resolveWithBridge(nativeId) {
             suspend()
         }
     }
@@ -157,7 +157,7 @@ class OfflineModule(context: ReactApplicationContext) : BitmovinBaseModule(conte
      */
     @ReactMethod
     fun cancelDownload(nativeId: NativeId, promise: Promise) {
-        promise.resolveWithBridge(nativeId) {
+        promise.unit.resolveWithBridge(nativeId) {
             cancelDownload()
         }
     }
@@ -168,7 +168,7 @@ class OfflineModule(context: ReactApplicationContext) : BitmovinBaseModule(conte
      */
     @ReactMethod
     fun usedStorage(nativeId: NativeId, promise: Promise) {
-        promise.resolveWithBridge(nativeId) {
+        promise.double.resolveWithBridge(nativeId) {
             offlineContentManager.usedStorage.toDouble()
         }
     }
@@ -179,7 +179,7 @@ class OfflineModule(context: ReactApplicationContext) : BitmovinBaseModule(conte
      */
     @ReactMethod
     fun deleteAll(nativeId: NativeId, promise: Promise) {
-        promise.resolveWithBridge(nativeId) {
+        promise.unit.resolveWithBridge(nativeId) {
             deleteAll()
         }
     }
@@ -192,7 +192,7 @@ class OfflineModule(context: ReactApplicationContext) : BitmovinBaseModule(conte
      */
     @ReactMethod
     fun downloadLicense(nativeId: NativeId, promise: Promise) {
-        promise.resolveWithBridge(nativeId) {
+        promise.unit.resolveWithBridge(nativeId) {
             downloadLicense()
         }
     }
@@ -205,7 +205,7 @@ class OfflineModule(context: ReactApplicationContext) : BitmovinBaseModule(conte
      */
     @ReactMethod
     fun releaseLicense(nativeId: NativeId, promise: Promise) {
-        promise.resolveWithBridge(nativeId) {
+        promise.unit.resolveWithBridge(nativeId) {
             releaseLicense()
         }
     }
@@ -218,7 +218,7 @@ class OfflineModule(context: ReactApplicationContext) : BitmovinBaseModule(conte
      */
     @ReactMethod
     fun renewOfflineLicense(nativeId: NativeId, promise: Promise) {
-        promise.resolveWithBridge(nativeId) {
+        promise.unit.resolveWithBridge(nativeId) {
             renewOfflineLicense()
         }
     }
@@ -231,18 +231,18 @@ class OfflineModule(context: ReactApplicationContext) : BitmovinBaseModule(conte
      */
     @ReactMethod
     fun release(nativeId: NativeId, promise: Promise) {
-        promise.resolveWithBridge(nativeId) {
+        promise.unit.resolveWithBridge(nativeId) {
             release()
             offlineContentManagerBridges.remove(nativeId)
         }
     }
 
-    private fun <T>Promise.resolveWithBridge(
+    private inline fun <T> TPromise<T>.resolveWithBridge(
         nativeId: NativeId,
-        runBlock: OfflineContentManagerBridge.() -> T,
+        crossinline block: OfflineContentManagerBridge.() -> T,
     ) {
         resolveOnCurrentThread {
-            getOfflineContentManagerBridge(nativeId).runBlock()
+            getOfflineContentManagerBridge(nativeId).block()
         }
     }
 }

android/src/main/java/com/bitmovin/player/reactnative/PlayerAnalyticsModule.kt

@@ -22,7 +22,7 @@ class PlayerAnalyticsModule(context: ReactApplicationContext) : BitmovinBaseModu
      */
     @ReactMethod
     fun sendCustomDataEvent(nativeId: NativeId, json: ReadableMap, promise: Promise) {
-        promise.resolveOnUIThread {
+        promise.unit.resolveOnUiThread {
             getPlayer(nativeId).analytics?.sendCustomDataEvent(json.toAnalyticsCustomData())
         }
     }
@@ -34,7 +34,7 @@ class PlayerAnalyticsModule(context: ReactApplicationContext) : BitmovinBaseModu
      */
     @ReactMethod
     fun getUserId(playerId: NativeId, promise: Promise) {
-        promise.resolveOnUIThread {
+        promise.string.nullable.resolveOnUiThread {
             getPlayer(playerId).analytics?.userId
         }
     }