[api] Auto-generate StringRef for incoming API string fields (#12648)

esphome/components/api/api_connection.cpp

@@ -473,7 +473,7 @@ void APIConnection::fan_command(const FanCommandRequest &msg) {
   if (msg.has_direction)
     call.set_direction(static_cast<fan::FanDirection>(msg.direction));
   if (msg.has_preset_mode)
-    call.set_preset_mode(reinterpret_cast<const char *>(msg.preset_mode), msg.preset_mode_len);
+    call.set_preset_mode(msg.preset_mode.c_str(), msg.preset_mode.size());
   call.perform();
 }
 #endif
@@ -559,7 +559,7 @@ void APIConnection::light_command(const LightCommandRequest &msg) {
   if (msg.has_flash_length)
     call.set_flash_length(msg.flash_length);
   if (msg.has_effect)
-    call.set_effect(reinterpret_cast<const char *>(msg.effect), msg.effect_len);
+    call.set_effect(msg.effect.c_str(), msg.effect.size());
   call.perform();
 }
 #endif
@@ -738,11 +738,11 @@ void APIConnection::climate_command(const ClimateCommandRequest &msg) {
   if (msg.has_fan_mode)
     call.set_fan_mode(static_cast<climate::ClimateFanMode>(msg.fan_mode));
   if (msg.has_custom_fan_mode)
-    call.set_fan_mode(reinterpret_cast<const char *>(msg.custom_fan_mode), msg.custom_fan_mode_len);
+    call.set_fan_mode(msg.custom_fan_mode.c_str(), msg.custom_fan_mode.size());
   if (msg.has_preset)
     call.set_preset(static_cast<climate::ClimatePreset>(msg.preset));
   if (msg.has_custom_preset)
-    call.set_preset(reinterpret_cast<const char *>(msg.custom_preset), msg.custom_preset_len);
+    call.set_preset(msg.custom_preset.c_str(), msg.custom_preset.size());
   if (msg.has_swing_mode)
     call.set_swing_mode(static_cast<climate::ClimateSwingMode>(msg.swing_mode));
   call.perform();
@@ -931,7 +931,7 @@ uint16_t APIConnection::try_send_select_info(EntityBase *entity, APIConnection *
 }
 void APIConnection::select_command(const SelectCommandRequest &msg) {
   ENTITY_COMMAND_MAKE_CALL(select::Select, select, select)
-  call.set_option(reinterpret_cast<const char *>(msg.state), msg.state_len);
+  call.set_option(msg.state.c_str(), msg.state.size());
   call.perform();
 }
 #endif
@@ -1153,9 +1153,8 @@ void APIConnection::on_get_time_response(const GetTimeResponse &value) {
   if (homeassistant::global_homeassistant_time != nullptr) {
     homeassistant::global_homeassistant_time->set_epoch_time(value.epoch_seconds);
 #ifdef USE_TIME_TIMEZONE
-    if (value.timezone_len > 0) {
-      homeassistant::global_homeassistant_time->set_timezone(reinterpret_cast<const char *>(value.timezone),
-                                                             value.timezone_len);
+    if (!value.timezone.empty()) {
+      homeassistant::global_homeassistant_time->set_timezone(value.timezone.c_str(), value.timezone.size());
     }
 #endif
   }
@@ -1522,7 +1521,7 @@ void APIConnection::complete_authentication_() {
 }
 
 bool APIConnection::send_hello_response(const HelloRequest &msg) {
-  this->client_info_.name.assign(reinterpret_cast<const char *>(msg.client_info), msg.client_info_len);
+  this->client_info_.name.assign(msg.client_info.c_str(), msg.client_info.size());
   this->client_info_.peername = this->helper_->getpeername();
   this->client_api_version_major_ = msg.api_version_major;
   this->client_api_version_minor_ = msg.api_version_minor;
@@ -1550,7 +1549,7 @@ bool APIConnection::send_hello_response(const HelloRequest &msg) {
 bool APIConnection::send_authenticate_response(const AuthenticationRequest &msg) {
   AuthenticationResponse resp;
   // bool invalid_password = 1;
-  resp.invalid_password = !this->parent_->check_password(msg.password, msg.password_len);
+  resp.invalid_password = !this->parent_->check_password(msg.password.byte(), msg.password.size());
   if (!resp.invalid_password) {
     this->complete_authentication_();
   }
@@ -1693,27 +1692,28 @@ bool APIConnection::send_device_info_response(const DeviceInfoRequest &msg) {
 #ifdef USE_API_HOMEASSISTANT_STATES
 void APIConnection::on_home_assistant_state_response(const HomeAssistantStateResponse &msg) {
   // Skip if entity_id is empty (invalid message)
-  if (msg.entity_id_len == 0) {
+  if (msg.entity_id.empty()) {
     return;
   }
 
   for (auto &it : this->parent_->get_state_subs()) {
     // Compare entity_id: check length matches and content matches
     size_t entity_id_len = strlen(it.entity_id);
-    if (entity_id_len != msg.entity_id_len || memcmp(it.entity_id, msg.entity_id, msg.entity_id_len) != 0) {
+    if (entity_id_len != msg.entity_id.size() ||
+        memcmp(it.entity_id, msg.entity_id.c_str(), msg.entity_id.size()) != 0) {
       continue;
     }
 
     // Compare attribute: either both have matching attribute, or both have none
     size_t sub_attr_len = it.attribute != nullptr ? strlen(it.attribute) : 0;
-    if (sub_attr_len != msg.attribute_len ||
-        (sub_attr_len > 0 && memcmp(it.attribute, msg.attribute, sub_attr_len) != 0)) {
+    if (sub_attr_len != msg.attribute.size() ||
+        (sub_attr_len > 0 && memcmp(it.attribute, msg.attribute.c_str(), sub_attr_len) != 0)) {
       continue;
     }
 
     // Create temporary string for callback (callback takes const std::string &)
-    // Handle empty state (nullptr with len=0)
-    std::string state(msg.state_len > 0 ? reinterpret_cast<const char *>(msg.state) : "", msg.state_len);
+    // Handle empty state
+    std::string state(!msg.state.empty() ? msg.state.c_str() : "", msg.state.size());
     it.callback(state);
   }
 }