Use "pd" JSON API call for direct preset apply (#2946)

wled00/data/index.js

@@ -2194,9 +2194,9 @@ function setPreset(i)
 {
 	var obj = {"ps":i};
 	if (pJson && pJson[i] && (!pJson[i].win || pJson[i].win.indexOf("Please") <= 0)) {
-		// we will send complete preset content as to avoid delay introduced by
-		// async nature of applyPreset(). json.cpp has to decide wether to call applyPreset()
-		// or not (by looking at the JSON content, if "ps" only)
+		// we will send the complete preset content as to avoid delay introduced by
+		// async nature of applyPreset() and having to read the preset from file system.
+		obj = {"pd":i}; // use "pd" instead of "ps" to indicate that we are sending the preset content directly
 		Object.assign(obj, pJson[i]);
 		delete obj.ql; // no need for quick load
 		delete obj.n;  // no need for name

wled00/json.cpp

@@ -394,31 +394,24 @@ bool deserializeState(JsonObject root, byte callMode, byte presetId)
     handleSet(nullptr, apireq, false);    // may set stateChanged
   }
 
-  // applying preset (2 cases: a) API call includes all preset values, b) API only specifies preset ID)
-  if (!root["ps"].isNull()) {
-    ps = presetCycCurr;
-    if (stateChanged) {
+  // applying preset (2 cases: a) API call includes all preset values ("pd"), b) API only specifies preset ID ("ps"))
+  byte presetToRestore = 0;
   // a) already applied preset content (requires "seg" or "win" but will ignore the rest)
-      currentPreset = root["ps"] | currentPreset;
-      // if preset contains HTTP API call do not change presetCycCurr
+  if (!root["pd"].isNull() && stateChanged) {
+    currentPreset = root[F("pd")] | currentPreset;
     if (root["win"].isNull()) presetCycCurr = currentPreset;
-      stateChanged = false; // cancel state change update (preset was set directly by applying values stored in UI JSON array)
-      notify(callMode);
-    } else if (root["win"].isNull() && getVal(root["ps"], &ps, 0, 0) && ps > 0 && ps < 251 && ps != currentPreset) {
+    presetToRestore = currentPreset; // stateUpdated() will clear the preset, so we need to restore it after
+    //unloadPlaylist(); // applying a preset unloads the playlist, may be needed here too?
+  } else if (!root["ps"].isNull()) {
+    ps = presetCycCurr;
+    if (root["win"].isNull() && getVal(root["ps"], &ps, 0, 0) && ps > 0 && ps < 251 && ps != currentPreset) {
       // b) preset ID only or preset that does not change state (use embedded cycling limits if they exist in getVal())
       presetCycCurr = ps;
-      presetId = ps;
-      root.remove("v");    // may be added in UI call
-      root.remove("time"); // may be added in UI call
-      root.remove("ps");
-      root.remove("on");   // some external calls add "on" to "ps" call
-      if (root.size() == 0) {
-        unloadPlaylist();  // we need to unload playlist
-        applyPreset(ps, callMode); // async load (only preset ID was specified)
+      unloadPlaylist();          // applying a preset unloads the playlist
+      applyPreset(ps, callMode); // async load from file system (only preset ID was specified)
       return stateResponse;
     }
   }
-  }
 
   JsonObject playlist = root[F("playlist")];
   if (!playlist.isNull() && loadPlaylist(playlist, presetId)) {
@@ -428,6 +421,7 @@ bool deserializeState(JsonObject root, byte callMode, byte presetId)
   }
 
   stateUpdated(callMode);
+  if (presetToRestore) currentPreset = presetToRestore;
 
   return stateResponse;
 }

wled00/presets.cpp

@@ -16,13 +16,13 @@ static char quickLoad[9];
 static char saveName[33];
 static bool includeBri = true, segBounds = true, selectedOnly = false, playlistSave = false;;
 
-static const char *getName(bool persist = true) {
+static const char *getFileName(bool persist = true) {
   return persist ? "/presets.json" : "/tmp.json";
 }
 
 static void doSaveState() {
   bool persist = (presetToSave < 251);
-  const char *filename = getName(persist);
+  const char *filename = getFileName(persist);
 
   if (!requestJSONBufferLock(10)) return; // will set fileDoc
 
@@ -83,7 +83,7 @@ bool getPresetName(byte index, String& name)
 {
   if (!requestJSONBufferLock(9)) return false;
   bool presetExists = false;
-  if (readObjectFromFileUsingId(getName(), index, &doc))
+  if (readObjectFromFileUsingId(getFileName(), index, &doc))
   { 
     JsonObject fdo = doc.as<JsonObject>();
     if (fdo["n"]) {
@@ -97,12 +97,12 @@ bool getPresetName(byte index, String& name)
 
 void initPresetsFile()
 {
-  if (WLED_FS.exists(getName())) return;
+  if (WLED_FS.exists(getFileName())) return;
 
   StaticJsonDocument<64> doc;
   JsonObject sObj = doc.to<JsonObject>();
   sObj.createNestedObject("0");
-  File f = WLED_FS.open(getName(), "w");
+  File f = WLED_FS.open(getFileName(), "w");
   if (!f) {
     errorFlag = ERR_FS_GENERAL;
     return;
@@ -127,14 +127,14 @@ void handlePresets()
     return;
   }
 
+  if (presetToApply == 0 || fileDoc) return; // no preset waiting to apply, or JSON buffer is already allocated, return to loop until free
+
   bool changePreset = false;
   uint8_t tmpPreset = presetToApply; // store temporary since deserializeState() may call applyPreset()
   uint8_t tmpMode   = callModeToApply;
 
-  if (tmpPreset == 0 || (fileDoc /*&& !force*/)) return; // JSON buffer already allocated and not force apply or no preset waiting
-
   JsonObject fdo;
-  const char *filename = getName(tmpPreset < 255);
+  const char *filename = getFileName(tmpPreset < 255);
 
   // allocate buffer
   if (!requestJSONBufferLock(9)) return;  // will also assign fileDoc
@@ -201,30 +201,28 @@ void savePreset(byte index, const char* pname, JsonObject sObj)
   presetToSave = index;
   playlistSave = false;
   if (sObj[F("ql")].is<const char*>()) strlcpy(quickLoad, sObj[F("ql")].as<const char*>(), 9); // client limits QL to 2 chars, buffer for 8 bytes to allow unicode
-  sObj.remove("v");
-  sObj.remove("time");
-  sObj.remove(F("error"));
-  sObj.remove(F("psave"));
-  if (sObj["o"].isNull()) { // "o" marks a playlist or manually entered API
+
+  if (sObj["o"].isNull()) { // no "o" means not a playlist or custom API call, saving of state is async (not immediately)
     includeBri   = sObj["ib"].as<bool>() || index==255; // temporary preset needs brightness
     segBounds    = sObj["sb"].as<bool>() || index==255; // temporary preset needs bounds
     selectedOnly = sObj[F("sc")].as<bool>();
     saveLedmap   = sObj[F("ledmap")] | -1;
-    sObj.remove("ib");
-    sObj.remove("sb");
-    sObj.remove(F("sc"));
   } else {
-    // this is a playlist or API
-    sObj.remove("o");
+    // this is a playlist or API call
     if (sObj[F("playlist")].isNull()) {
-      presetToSave = 0; // we will save API immediately
-      if (index < 251 && fileDoc) {
+      // we will save API call immediately
+      presetToSave = 0;
+      if (index > 250 || !fileDoc) return; // cannot save API calls to temporary preset (255)
+      sObj.remove("o");
+      sObj.remove("v");
+      sObj.remove("time");
+      sObj.remove(F("error"));
+      sObj.remove(F("psave"));
       if (sObj["n"].isNull()) sObj["n"] = saveName;
       initPresetsFile(); // just in case if someone deleted presets.json using /edit
-        writeObjectToFileUsingId(getName(index), index, fileDoc);
+      writeObjectToFileUsingId(getFileName(index), index, fileDoc);
       presetsModifiedTime = toki.second(); //unix time
       updateFSInfo();
-      }
     } else {
       // store playlist
       includeBri   = true; // !sObj["on"].isNull();
@@ -235,7 +233,7 @@ void savePreset(byte index, const char* pname, JsonObject sObj)
 
 void deletePreset(byte index) {
   StaticJsonDocument<24> empty;
-  writeObjectToFileUsingId(getName(), index, &empty);
+  writeObjectToFileUsingId(getFileName(), index, &empty);
   presetsModifiedTime = toki.second(); //unix time
   updateFSInfo();
 }