fixed ble adv

script/api_protobuf/api_protobuf.py

@@ -339,6 +339,11 @@ def create_field_type_info(
 ) -> TypeInfo:
     """Create the appropriate TypeInfo instance for a field, handling repeated fields and custom options."""
     if field.label == 3:  # repeated
+        # Check if this repeated field has fixed_array_with_length_define option
+        if (
+            fixed_size := get_field_opt(field, pb.fixed_array_with_length_define)
+        ) is not None:
+            return FixedArrayWithLengthRepeatedType(field, fixed_size)
         # Check if this repeated field has fixed_array_size option
         if (fixed_size := get_field_opt(field, pb.fixed_array_size)) is not None:
             return FixedArrayRepeatedType(field, fixed_size)
@@ -1230,6 +1235,72 @@ class FixedArrayRepeatedType(TypeInfo):
         return underlying_size * self.array_size
 
 
+class FixedArrayWithLengthRepeatedType(FixedArrayRepeatedType):
+    """Special type for fixed-size repeated fields with variable length tracking.
+
+    Similar to FixedArrayRepeatedType but generates an additional length field
+    to track how many elements are actually in use. Only encodes/sends elements
+    up to the current length.
+
+    Fixed arrays with length are only supported for encoding (SOURCE_SERVER) since
+    we cannot control how many items we receive when decoding.
+    """
+
+    @property
+    def public_content(self) -> list[str]:
+        # Return both the array and the length field
+        return [
+            f"{self.cpp_type} {self.field_name}{{}};",
+            f"uint16_t {self.field_name}_len{{0}};",
+        ]
+
+    @property
+    def encode_content(self) -> str:
+        # Helper to generate encode statement for a single element
+        def encode_element(element: str) -> str:
+            if isinstance(self._ti, EnumType):
+                return f"buffer.{self._ti.encode_func}({self.number}, static_cast<uint32_t>({element}), true);"
+            return f"buffer.{self._ti.encode_func}({self.number}, {element}, true);"
+
+        # Always use a loop up to the current length
+        o = f"for (uint16_t i = 0; i < this->{self.field_name}_len; i++) {{\n"
+        o += f"  {encode_element(f'this->{self.field_name}[i]')}\n"
+        o += "}"
+        return o
+
+    @property
+    def dump_content(self) -> str:
+        # Dump only the active elements
+        o = f"for (uint16_t i = 0; i < this->{self.field_name}_len; i++) {{\n"
+        # Check if underlying type can use dump_field
+        if type(self._ti).can_use_dump_field():
+            o += f'  dump_field(out, "{self.name}", {self._ti.dump_field_value(f"this->{self.field_name}[i]")}, 4);\n'
+        else:
+            o += f'  out.append("  {self.name}: ");\n'
+            o += indent(self._ti.dump(f"this->{self.field_name}[i]")) + "\n"
+            o += '  out.append("\\n");\n'
+        o += "}"
+        return o
+
+    def get_size_calculation(self, name: str, force: bool = False) -> str:
+        # Calculate size only for active elements
+        o = f"for (uint16_t i = 0; i < {name}_len; i++) {{\n"
+        o += f"  {self._ti.get_size_calculation(f'{name}[i]', True)}\n"
+        o += "}"
+        return o
+
+    def get_estimated_size(self) -> int:
+        # For fixed arrays with length, estimate based on typical usage
+        # Assume on average half the array is used
+        underlying_size = self._ti.get_estimated_size()
+        if self.is_define:
+            # When using a define, estimate 8 elements as typical
+            return underlying_size * 8
+        return underlying_size * (
+            self.array_size // 2 if self.array_size > 2 else self.array_size
+        )
+
+
 class RepeatedTypeInfo(TypeInfo):
     def __init__(self, field: descriptor.FieldDescriptorProto) -> None:
         super().__init__(field)
@@ -1711,6 +1782,19 @@ def build_message_type(
                 f"since we cannot trust or control the number of items received from clients."
             )
 
+        # Validate that fixed_array_with_length_define is only used in encode-only messages
+        if (
+            needs_decode
+            and field.label == 3
+            and get_field_opt(field, pb.fixed_array_with_length_define) is not None
+        ):
+            raise ValueError(
+                f"Message '{desc.name}' uses fixed_array_with_length_define on field '{field.name}' "
+                f"but has source={SOURCE_NAMES[source]}. "
+                f"Fixed arrays with length are only supported for SOURCE_SERVER (encode-only) messages "
+                f"since we cannot trust or control the number of items received from clients."
+            )
+
         ti = create_field_type_info(field, needs_decode, needs_encode)
 
         # Skip field declarations for fields that are in the base class