From 3a3059acb33109229e0e6702bd91434a906a9015 Mon Sep 17 00:00:00 2001
From: Emma <marmadilemanteater@proton.me>
Date: Tue, 28 Jan 2025 08:00:36 -0500
Subject: [PATCH] Replace jsCommunicator calls with new promise class

(benefits): allows for more concise passing of JSON back to the js side
---
 .../freetubeapp/freetube/helpers/Promise.kt   | 71 +++++++++++++++++++
 .../javascript/FreeTubeJavaScriptInterface.kt | 17 +++--
 2 files changed, 81 insertions(+), 7 deletions(-)
 create mode 100644 android/app/src/main/java/io/freetubeapp/freetube/helpers/Promise.kt

diff --git a/android/app/src/main/java/io/freetubeapp/freetube/helpers/Promise.kt b/android/app/src/main/java/io/freetubeapp/freetube/helpers/Promise.kt
new file mode 100644
index 0000000000000..c03c8814f30bc
--- /dev/null
+++ b/android/app/src/main/java/io/freetubeapp/freetube/helpers/Promise.kt
@@ -0,0 +1,71 @@
+package io.freetubeapp.freetube.helpers
+
+import io.freetubeapp.freetube.javascript.AsyncJSCommunicator
+import java.util.UUID.randomUUID
+import java.util.concurrent.ThreadPoolExecutor
+
+class Promise<T, G> {
+  private val successListeners: MutableList<(T) -> Unit> = mutableListOf()
+  private var successResult: T? = null
+  private val errorListeners: MutableList<(G) -> Unit> = mutableListOf()
+  private var errorResult: G? = null
+  private val id = "${randomUUID()}"
+
+  constructor(executor: ThreadPoolExecutor, runnable: ((T) -> Unit, (G) -> Unit) -> Unit) {
+    executor.run {
+      runnable.invoke({
+        result ->
+        notifySuccess(result)
+      }, {
+        result ->
+        notifyError(result)
+      })
+    }
+  }
+
+  fun addJsCommunicator(communicator: AsyncJSCommunicator) : String {
+    then {
+      communicator.resolve(id, "$it")
+    }
+    catch {
+      communicator.reject(id, "$it")
+    }
+    return id
+  }
+
+  fun notifySuccess(result: T) {
+    successResult = result
+    successListeners.forEach {
+      listener ->
+      listener.invoke(result)
+    }
+  }
+
+  fun notifyError(result: G) {
+    errorResult = result
+    errorListeners.forEach {
+      listener ->
+      listener.invoke(result)
+    }
+  }
+
+  fun then(listener: (T) -> Unit): Promise<T, G> {
+    if (successResult != null) {
+      // assume success result won't be unset
+      listener(successResult!!)
+    } else {
+      successListeners.add(listener)
+    }
+    return this
+  }
+
+  fun catch(listener: (G) -> Unit): Promise<T, G> {
+    if (errorResult != null) {
+      // assume success result won't be unset
+      listener(errorResult!!)
+    } else {
+      errorListeners.add(listener)
+    }
+    return this
+  }
+}
diff --git a/android/app/src/main/java/io/freetubeapp/freetube/javascript/FreeTubeJavaScriptInterface.kt b/android/app/src/main/java/io/freetubeapp/freetube/javascript/FreeTubeJavaScriptInterface.kt
index bc2a1b438b7b7..492a6a74650d2 100644
--- a/android/app/src/main/java/io/freetubeapp/freetube/javascript/FreeTubeJavaScriptInterface.kt
+++ b/android/app/src/main/java/io/freetubeapp/freetube/javascript/FreeTubeJavaScriptInterface.kt
@@ -26,6 +26,8 @@ import androidx.documentfile.provider.DocumentFile
 import io.freetubeapp.freetube.MainActivity
 import io.freetubeapp.freetube.MediaControlsReceiver
 import io.freetubeapp.freetube.R
+import io.freetubeapp.freetube.helpers.Promise
+import org.json.JSONObject
 import java.io.File
 import java.io.FileInputStream
 import java.net.URL
@@ -375,24 +377,25 @@ class FreeTubeJavaScriptInterface {
    */
   @JavascriptInterface
   fun readFile(basedir: String, filename: String): String {
-    val promise = jsCommunicator.jsPromise()
-    context.threadPoolExecutor.execute {
+    val promise = Promise(context.threadPoolExecutor, {
+      resolve,
+      reject ->
       try {
         if (basedir.startsWith("content://")) {
           val stream = context.contentResolver.openInputStream(Uri.parse(basedir))
           val content = String(stream!!.readBytes())
           stream!!.close()
-          jsCommunicator.resolve(promise, content)
+          resolve(content)
         } else {
           val path = getDirectory(basedir)
           val file = File(path, filename)
-          jsCommunicator.resolve(promise, FileInputStream(file).bufferedReader().use { it.readText() })
+          resolve(FileInputStream(file).bufferedReader().use { it.readText() })
         }
       } catch (ex: Exception) {
-        jsCommunicator.reject(promise, ex.stackTraceToString())
+        reject(ex.stackTraceToString())
       }
-    }
-    return promise
+    })
+    return promise.addJsCommunicator(jsCommunicator)
   }
 
   /**