From 7cea4a293c2ea5505843f6c9b2feef74faf128a0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sergio=20Mart=C3=ADnez=20Portela?=
 <sergio@codigoparallevar.com>
Date: Tue, 2 Jun 2020 13:23:15 +0200
Subject: [PATCH] Add simple memory cache for enum/callback values.

---
 .../parts/values/StaticValuePart.java         | 10 ++++--
 .../com/programaker/api/ProgramakerApi.kt     | 33 ++++++++++++++++++-
 2 files changed, 39 insertions(+), 4 deletions(-)

diff --git a/app/src/main/java/com/codigoparallevar/minicards/parts/values/StaticValuePart.java b/app/src/main/java/com/codigoparallevar/minicards/parts/values/StaticValuePart.java
index 3f42251..1590eca 100644
--- a/app/src/main/java/com/codigoparallevar/minicards/parts/values/StaticValuePart.java
+++ b/app/src/main/java/com/codigoparallevar/minicards/parts/values/StaticValuePart.java
@@ -31,6 +31,7 @@ import com.codigoparallevar.minicards.types.functional.Tuple3;
 import com.codigoparallevar.minicards.types.wireData.WireDataType;
 import com.codigoparallevar.minicards.ui_helpers.GetAsync;
 import com.codigoparallevar.minicards.utils.Serializations;
+import com.programaker.api.ProgramakerApi;
 import com.programaker.api.data.ProgramakerCustomBlockArgument;
 import com.programaker.api.data.ProgramakerCustomBlockArgumentValue;
 
@@ -290,12 +291,15 @@ public class StaticValuePart implements Part {
                     break;
                 }
 
+                ProgramakerApi api = _grid.getApi();
                 Dialog loadingDialog = createLoadingDialog(ctx);
-                loadingDialog.show();
+                if (!api.hasCachedAllowedValues(blockArg)) {
+                    loadingDialog.show();
+                }
 
                 new GetAsync<List<ProgramakerCustomBlockArgumentValue>>().executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR,
                         new Tuple3<>(
-                                () -> _grid.getApi().fetchAllowedValues(blockArg),
+                                () -> api.fetchAllowedValues(blockArg),
                                 results -> {
                                     Log.i(LogTag, "Result: " + results);
                                     loadingDialog.cancel();
@@ -330,7 +334,7 @@ public class StaticValuePart implements Part {
     private Dialog createItemDialog(Context ctx, CharSequence[] itemNames, Consumer<Integer> onSelected) {
         final AlertDialog.Builder builder = new AlertDialog.Builder(ctx);
 
-        builder.setTitle(R.string.loading_available_values);
+        builder.setTitle(R.string.set_value);
 
         final ProgressBar progressBar = new ProgressBar(ctx);
         progressBar.setIndeterminate(true);
diff --git a/app/src/main/java/com/programaker/api/ProgramakerApi.kt b/app/src/main/java/com/programaker/api/ProgramakerApi.kt
index 61b68cd..4780e2f 100644
--- a/app/src/main/java/com/programaker/api/ProgramakerApi.kt
+++ b/app/src/main/java/com/programaker/api/ProgramakerApi.kt
@@ -22,6 +22,7 @@ import java.net.URLConnection
 
 
 class ProgramakerApi(private val ApiRoot: String="https://programaker.com/api") {
+    private val enumCallbackCache: MutableMap<String, List<ProgramakerCustomBlockArgumentValue>> = HashMap()
     private val LogTag: String = "ProgramakerApi"
 
     private var userId: String? = null
@@ -137,7 +138,13 @@ class ProgramakerApi(private val ApiRoot: String="https://programaker.com/api")
     }
 
     fun fetchAllowedValues(blockArg: ProgramakerCustomBlockArgument): List<ProgramakerCustomBlockArgumentValue>? {
-        val conn = URL(getArgumentValuesUrl(blockArg)).openConnection() as HttpURLConnection
+        val url = getArgumentValuesUrl(blockArg)
+        val cachedValues = cachedAllowedValues(url)
+        if (cachedValues != null) {
+            return cachedValues
+        }
+
+        val conn = URL(url).openConnection() as HttpURLConnection
 
         addAuthHeader(conn)
 
@@ -156,6 +163,7 @@ class ProgramakerApi(private val ApiRoot: String="https://programaker.com/api")
             Log.e(LogTag, ex.toString(), ex)
             return null
         }
+        cacheValues(url, results)
         return results
     }
 
@@ -344,6 +352,29 @@ class ProgramakerApi(private val ApiRoot: String="https://programaker.com/api")
         }
     }
 
+    // Simple result caching
+    private fun cacheValues(url: String, results: List<ProgramakerCustomBlockArgumentValue>) {
+        enumCallbackCache[url] = results
+    }
+
+    private fun cachedAllowedValues(url: String): List<ProgramakerCustomBlockArgumentValue>? {
+        if (enumCallbackCache.containsKey(url)) {
+            return enumCallbackCache[url]
+        }
+        return null
+    }
+
+    fun hasCachedAllowedValues(blockArg: ProgramakerCustomBlockArgument): Boolean {
+        if (userId == null) {
+            // This will be required to fully form the URL.
+            // Also, without it, it's not possible to have cached values. We can safely discard it
+            return false
+        }
+        val url = getArgumentValuesUrl(blockArg)
+        return enumCallbackCache.containsKey(url)
+    }
+
+    // Utils
     private fun <T>parseJson(content: InputStream, resultClass: Type): T {
         val reader = InputStreamReader(content)
         val gson = Gson()