From 29dcc4031f9cc0d6b1044003da1ac72bc7e71c93 Mon Sep 17 00:00:00 2001
From: Samuel Sieb <samuel-github@sieb.net>
Date: Mon, 4 Dec 2023 15:41:33 -0800
Subject: [PATCH] fix a01nyub data reading (#5882)

Co-authored-by: Samuel Sieb <samuel@sieb.net>
---
 esphome/components/a01nyub/a01nyub.cpp | 49 ++++++++++----------------
 1 file changed, 18 insertions(+), 31 deletions(-)

diff --git a/esphome/components/a01nyub/a01nyub.cpp b/esphome/components/a01nyub/a01nyub.cpp
index 75cb276f84..d0bc89a0c9 100644
--- a/esphome/components/a01nyub/a01nyub.cpp
+++ b/esphome/components/a01nyub/a01nyub.cpp
@@ -8,50 +8,37 @@ namespace esphome {
 namespace a01nyub {
 
 static const char *const TAG = "a01nyub.sensor";
-static const uint8_t MAX_DATA_LENGTH_BYTES = 4;
 
 void A01nyubComponent::loop() {
   uint8_t data;
   while (this->available() > 0) {
-    if (this->read_byte(&data)) {
-      buffer_.push_back(data);
+    this->read_byte(&data);
+    if (this->buffer_.empty() && (data != 0xff))
+      continue;
+    buffer_.push_back(data);
+    if (this->buffer_.size() == 4)
       this->check_buffer_();
-    }
   }
 }
 
 void A01nyubComponent::check_buffer_() {
-  if (this->buffer_.size() >= MAX_DATA_LENGTH_BYTES) {
-    size_t i;
-    for (i = 0; i < this->buffer_.size(); i++) {
-      // Look for the first packet
-      if (this->buffer_[i] == 0xFF) {
-        if (i + 1 + 3 < this->buffer_.size()) {  // Packet is not complete
-          return;                                // Wait for completion
-        }
-
-        uint8_t checksum = (this->buffer_[i] + this->buffer_[i + 1] + this->buffer_[i + 2]) & 0xFF;
-        if (this->buffer_[i + 3] == checksum) {
-          float distance = (this->buffer_[i + 1] << 8) + this->buffer_[i + 2];
-          if (distance > 280) {
-            float meters = distance / 1000.0;
-            ESP_LOGV(TAG, "Distance from sensor: %f mm, %f m", distance, meters);
-            this->publish_state(meters);
-          } else {
-            ESP_LOGW(TAG, "Invalid data read from sensor: %s", format_hex_pretty(this->buffer_).c_str());
-          }
-        }
-        break;
-      }
+  uint8_t checksum = this->buffer_[0] + this->buffer_[1] + this->buffer_[2];
+  if (this->buffer_[3] == checksum) {
+    float distance = (this->buffer_[1] << 8) + this->buffer_[2];
+    if (distance > 280) {
+      float meters = distance / 1000.0;
+      ESP_LOGV(TAG, "Distance from sensor: %f mm, %f m", distance, meters);
+      this->publish_state(meters);
+    } else {
+      ESP_LOGW(TAG, "Invalid data read from sensor: %s", format_hex_pretty(this->buffer_).c_str());
     }
-    this->buffer_.clear();
+  } else {
+    ESP_LOGW(TAG, "checksum failed: %02x != %02x", checksum, this->buffer_[3]);
   }
+  this->buffer_.clear();
 }
 
-void A01nyubComponent::dump_config() {
-  ESP_LOGCONFIG(TAG, "A01nyub Sensor:");
-  LOG_SENSOR("  ", "Distance", this);
-}
+void A01nyubComponent::dump_config() { LOG_SENSOR("", "A01nyub Sensor", this); }
 
 }  // namespace a01nyub
 }  // namespace esphome