From 027e0fd6f06c7fe3cb8f90b003dd2b240a29d2a3 Mon Sep 17 00:00:00 2001
From: Hermet Park <hermetpark@gmail.com>
Date: Sat, 4 May 2024 15:19:26 +0900
Subject: [PATCH] lottie/expressions: enhance stability

When the system fails to interpret the expression code,
it forcibly disables the feature per property.

This improvement enhances stability and performance
by avoiding reckless attempts to interpret JavaScript code.

When we confirm the full stability with expressions,
we can revert this code.
---
 src/loaders/lottie/tvgLottieExpressions.cpp |  5 ++++-
 src/loaders/lottie/tvgLottieParser.cpp      |  1 +
 src/loaders/lottie/tvgLottieProperty.h      | 10 ++++++----
 3 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/src/loaders/lottie/tvgLottieExpressions.cpp b/src/loaders/lottie/tvgLottieExpressions.cpp
index 4b7e1177..a8494a49 100644
--- a/src/loaders/lottie/tvgLottieExpressions.cpp
+++ b/src/loaders/lottie/tvgLottieExpressions.cpp
@@ -1219,7 +1219,10 @@ jerry_value_t LottieExpressions::evaluate(float frameNo, LottieExpression* exp)
     //evaluate the code
     auto eval = jerry_eval((jerry_char_t *) exp->code, strlen(exp->code), JERRY_PARSE_NO_OPTS);
 
-    if (jerry_value_is_exception(eval)) return jerry_undefined();
+    if (jerry_value_is_exception(eval)) {
+        exp->enabled = false;  // The feature is experimental, it will be forcely turned off if it's incompatible.
+        return jerry_undefined();
+    }
 
     jerry_value_free(eval);
 
diff --git a/src/loaders/lottie/tvgLottieParser.cpp b/src/loaders/lottie/tvgLottieParser.cpp
index ca1175ce..159ef2a3 100644
--- a/src/loaders/lottie/tvgLottieParser.cpp
+++ b/src/loaders/lottie/tvgLottieParser.cpp
@@ -45,6 +45,7 @@ static LottieExpression* _expression(char* code, LottieComposition* comp, Lottie
     inst->object = object;
     inst->property = property;
     inst->type = type;
+    inst->enabled = true;
 
     return inst;
 }
diff --git a/src/loaders/lottie/tvgLottieProperty.h b/src/loaders/lottie/tvgLottieProperty.h
index f7aea077..85720c8a 100644
--- a/src/loaders/lottie/tvgLottieProperty.h
+++ b/src/loaders/lottie/tvgLottieProperty.h
@@ -194,6 +194,8 @@ struct LottieExpression
     LottieProperty* property;
     LottieProperty::Type type;
 
+    bool enabled;
+
     struct {
         uint32_t key = 0;      //the keyframe number repeating to
         float in = FLT_MAX;    //looping duration in frame number
@@ -367,7 +369,7 @@ struct LottieGenericProperty : LottieProperty
     T operator()(float frameNo, LottieExpressions* exps)
     {
         T out{};
-        if (exps && exp) {
+        if (exps && (exp && exp->enabled)) {
             if (exp->loop.mode != LottieExpression::LoopMode::None) frameNo = _loop(frames, frameNo, exp);
             if (exps->result<LottieGenericProperty<T>>(frameNo, out, exp)) return out;
         }
@@ -507,7 +509,7 @@ struct LottiePathSet : LottieProperty
 
     bool operator()(float frameNo, Array<PathCommand>& cmds, Array<Point>& pts, Matrix* transform, LottieExpressions* exps)
     {
-        if (exps && exp) {
+        if (exps && (exp && exp->enabled)) {
             if (exp->loop.mode != LottieExpression::LoopMode::None) frameNo = _loop(frames, frameNo, exp);
             if (exps->result<LottiePathSet>(frameNo, cmds, pts, transform, exp)) return true;
         }
@@ -588,7 +590,7 @@ struct LottieColorStop : LottieProperty
 
     Result operator()(float frameNo, Fill* fill, LottieExpressions* exps)
     {
-        if (exps && exp) {
+        if (exps && (exp && exp->enabled)) {
             if (exp->loop.mode != LottieExpression::LoopMode::None) frameNo = _loop(frames, frameNo, exp);
             if (exps->result<LottieColorStop>(frameNo, fill, exp)) return Result::Success;
         }
@@ -724,7 +726,7 @@ struct LottiePosition : LottieProperty
     Point operator()(float frameNo, LottieExpressions* exps)
     {
         Point out{};
-        if (exps && exp) {
+        if (exps && (exp && exp->enabled)) {
             if (exp->loop.mode != LottieExpression::LoopMode::None) frameNo = _loop(frames, frameNo, exp);
             if (exps->result<LottiePosition>(frameNo, out, exp)) return out;
         }