Nextion TFT upload IDF memory optimization (#6128)

* Nextion TFT upload IDF memory optimization

This optimizes the memory in use for TFT upload when using `esp-idf` framework.

Basically, the engine establishes 3 connections to the the http/https server:
1. Fetch the file size (used to manage chunks and file size)
2. Transfer the 1st chunk (when it evaluates Nextion response to define either to continue from that point or to another point in the file)
3. Transfer the remaining data.

Until now, connection 1 was kept open during the whole process taking aprox 40kb of heap in a esp32dev (NSPanel in my tests) and the same amount of memory was needed to the 2nd and 3rd connections (which never competes to each other).
With this change, each connection is closed and released before opening the next one with a significant reduction on the required heap needed for this transfer.

This can still be improved to use a persistent connection, but I will look at this in the future, so it is not part of this change.

In addition to the better connection management, I've added quite a lot of log (mostly at VERBOSE level), which was used for troubleshooting here.
I was unsure about removing this. As it can be useful for others, I decided to keep it, but I will be fine about removing it if this is now in line with ESPHome best practices.

* clang-format

* Log response length

esphome/components/nextion/nextion_upload_idf.cpp

@@ -24,7 +24,7 @@ int Nextion::upload_range(const std::string &url, int range_start) {
   ESP_LOGVV(TAG, "url: %s", url.c_str());
   uint range_size = this->tft_size_ - range_start;
   ESP_LOGVV(TAG, "tft_size_: %i", this->tft_size_);
-  ESP_LOGV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
+  ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
   int range_end = (range_start == 0) ? std::min(this->tft_size_, 16383) : this->tft_size_;
   if (range_size <= 0 or range_end <= range_start) {
     ESP_LOGE(TAG, "Invalid range");
@@ -67,12 +67,13 @@ int Nextion::upload_range(const std::string &url, int range_start) {
 
   int total_read_len = 0, read_len;
 
+  ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
   ESP_LOGV(TAG, "Allocate buffer");
   uint8_t *buffer = new uint8_t[4096];
   std::string recv_string;
   if (buffer == nullptr) {
     ESP_LOGE(TAG, "Failed to allocate memory for buffer");
-    ESP_LOGV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
+    ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
   } else {
     ESP_LOGV(TAG, "Memory for buffer allocated successfully");
 
@@ -86,15 +87,14 @@ int Nextion::upload_range(const std::string &url, int range_start) {
         ESP_LOGVV(TAG, "Write to UART successful");
         this->recv_ret_string_(recv_string, 5000, true);
         this->content_length_ -= read_len;
-        ESP_LOGD(TAG, "Uploaded %0.2f %%, remaining %d bytes",
+        ESP_LOGD(TAG, "Uploaded %0.2f %%, remaining %d bytes, heap is %" PRIu32 " bytes",
-                 100.0 * (this->tft_size_ - this->content_length_) / this->tft_size_, this->content_length_);
+                 100.0 * (this->tft_size_ - this->content_length_) / this->tft_size_, this->content_length_,
-        if (recv_string[0] != 0x05) {  // 0x05 == "ok"
+                 esp_get_free_heap_size());
+
+        if (recv_string[0] == 0x08 && recv_string.size() == 5) {  // handle partial upload request
           ESP_LOGD(
               TAG, "recv_string [%s]",
               format_hex_pretty(reinterpret_cast<const uint8_t *>(recv_string.data()), recv_string.size()).c_str());
-        }
-        // handle partial upload request
-        if (recv_string[0] == 0x08 && recv_string.size() == 5) {
           uint32_t result = 0;
           for (int j = 0; j < 4; ++j) {
             result += static_cast<uint8_t>(recv_string[j + 1]) << (8 * j);
@@ -103,13 +103,37 @@ int Nextion::upload_range(const std::string &url, int range_start) {
             ESP_LOGI(TAG, "Nextion reported new range %" PRIu32, result);
             this->content_length_ = this->tft_size_ - result;
             // Deallocate the buffer when done
+            ESP_LOGV(TAG, "Deallocate buffer");
+            ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
             delete[] buffer;
             ESP_LOGVV(TAG, "Memory for buffer deallocated");
-            esp_http_client_cleanup(client);
+            ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
+            ESP_LOGV(TAG, "Close http client");
+            ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
             esp_http_client_close(client);
+            esp_http_client_cleanup(client);
+            ESP_LOGVV(TAG, "Client closed");
+            ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
             return result;
           }
+        } else if (recv_string[0] != 0x05) {  // 0x05 == "ok"
+          ESP_LOGE(
+              TAG, "Invalid response from Nextion: [%s]",
+              format_hex_pretty(reinterpret_cast<const uint8_t *>(recv_string.data()), recv_string.size()).c_str());
+          ESP_LOGV(TAG, "Deallocate buffer");
+          ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
+          delete[] buffer;
+          ESP_LOGVV(TAG, "Memory for buffer deallocated");
+          ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
+          ESP_LOGV(TAG, "Close http client");
+          ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
+          esp_http_client_close(client);
+          esp_http_client_cleanup(client);
+          ESP_LOGVV(TAG, "Client closed");
+          ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
+          return -1;
         }
+
         recv_string.clear();
       } else if (read_len == 0) {
         ESP_LOGV(TAG, "End of HTTP response reached");
@@ -121,11 +145,18 @@ int Nextion::upload_range(const std::string &url, int range_start) {
     }
 
     // Deallocate the buffer when done
+    ESP_LOGV(TAG, "Deallocate buffer");
+    ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
     delete[] buffer;
     ESP_LOGVV(TAG, "Memory for buffer deallocated");
+    ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
   }
-  esp_http_client_cleanup(client);
+  ESP_LOGV(TAG, "Close http client");
+  ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
   esp_http_client_close(client);
+  esp_http_client_cleanup(client);
+  ESP_LOGVV(TAG, "Client closed");
+  ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
   return range_end + 1;
 }
 
@@ -159,7 +190,7 @@ bool Nextion::upload_tft() {
 
   // Initialize the HTTP client with the configuration
   ESP_LOGV(TAG, "Initializing HTTP client");
-  ESP_LOGV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
+  ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
   esp_http_client_handle_t http = esp_http_client_init(&config);
   if (!http) {
     ESP_LOGE(TAG, "Failed to initialize HTTP client.");
@@ -168,7 +199,7 @@ bool Nextion::upload_tft() {
 
   // Perform the HTTP request
   ESP_LOGV(TAG, "Check if the client could connect");
-  ESP_LOGV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
+  ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
   esp_err_t err = esp_http_client_perform(http);
   if (err != ESP_OK) {
     ESP_LOGE(TAG, "HTTP request failed: %s", esp_err_to_name(err));
@@ -177,14 +208,22 @@ bool Nextion::upload_tft() {
   }
 
   // Check the HTTP Status Code
+  ESP_LOGV(TAG, "Check the HTTP Status Code");
+  ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
   int status_code = esp_http_client_get_status_code(http);
   ESP_LOGV(TAG, "HTTP Status Code: %d", status_code);
   size_t tft_file_size = esp_http_client_get_content_length(http);
   ESP_LOGD(TAG, "TFT file size: %zu", tft_file_size);
 
+  ESP_LOGD(TAG, "Close HTTP connection");
+  ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
+  esp_http_client_close(http);
+  esp_http_client_cleanup(http);
+  ESP_LOGVV(TAG, "Connection closed");
+  ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
+
   if (tft_file_size < 4096) {
     ESP_LOGE(TAG, "File size check failed. Size: %zu", tft_file_size);
-    esp_http_client_cleanup(http);
     return this->upload_end(false);
   } else {
     ESP_LOGV(TAG, "File size check passed. Proceeding...");
@@ -193,8 +232,10 @@ bool Nextion::upload_tft() {
   this->tft_size_ = tft_file_size;
 
   ESP_LOGD(TAG, "Updating Nextion");
-  // The Nextion will ignore the update command if it is sleeping
 
+  // The Nextion will ignore the update command if it is sleeping
+  ESP_LOGV(TAG, "Wake-up Nextion");
+  ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
   this->send_command_("sleep=0");
   this->set_backlight_brightness(1.0);
   vTaskDelay(pdMS_TO_TICKS(250));  // NOLINT
@@ -207,26 +248,31 @@ bool Nextion::upload_tft() {
   sprintf(command, "whmi-wris %d,%" PRIu32 ",1", this->content_length_, this->parent_->get_baud_rate());
 
   // Clear serial receive buffer
+  ESP_LOGV(TAG, "Clear serial receive buffer");
+  ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
   uint8_t d;
   while (this->available()) {
     this->read_byte(&d);
   };
 
+  ESP_LOGV(TAG, "Send update instruction: %s", command);
+  ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
   this->send_command_(command);
 
   std::string response;
   ESP_LOGV(TAG, "Waiting for upgrade response");
-  this->recv_ret_string_(response, 2048, true);  // This can take some time to return
+  this->recv_ret_string_(response, 5000, true);  // This can take some time to return
 
   // The Nextion display will, if it's ready to accept data, send a 0x05 byte.
-  ESP_LOGD(TAG, "Upgrade response is [%s]",
+  ESP_LOGD(TAG, "Upgrade response is [%s] - %zu bytes",
-           format_hex_pretty(reinterpret_cast<const uint8_t *>(response.data()), response.size()).c_str());
+           format_hex_pretty(reinterpret_cast<const uint8_t *>(response.data()), response.size()).c_str(),
+           response.length());
+  ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
 
   if (response.find(0x05) != std::string::npos) {
     ESP_LOGV(TAG, "Preparation for tft update done");
   } else {
     ESP_LOGE(TAG, "Preparation for tft update failed %d \"%s\"", response[0], response.c_str());
-    esp_http_client_cleanup(http);
     return this->upload_end(false);
   }
 
@@ -234,12 +280,12 @@ bool Nextion::upload_tft() {
            content_length_, esp_get_free_heap_size());
 
   ESP_LOGV(TAG, "Starting transfer by chunks loop");
+  ESP_LOGVV(TAG, "Available heap: %" PRIu32, esp_get_free_heap_size());
   int result = 0;
   while (content_length_ > 0) {
     result = upload_range(this->tft_url_.c_str(), result);
     if (result < 0) {
       ESP_LOGE(TAG, "Error updating Nextion!");
-      esp_http_client_cleanup(http);
       return this->upload_end(false);
     }
     App.feed_wdt();
@@ -248,9 +294,6 @@ bool Nextion::upload_tft() {
 
   ESP_LOGD(TAG, "Successfully updated Nextion!");
 
-  ESP_LOGD(TAG, "Close HTTP connection");
-  esp_http_client_close(http);
-  esp_http_client_cleanup(http);
   return upload_end(true);
 }