From 58e6493ca0e0b37e9072973c511511d58f1ab0a6 Mon Sep 17 00:00:00 2001
From: Alija Bobija <bobija.alija@gmail.com>
Date: Wed, 11 Sep 2024 12:16:14 +0200
Subject: [PATCH] UID as struct of bytes array and length

---
 examples/basic/main/basic.c |  5 +++--
 examples/i2c/main/i2c.c     |  5 +++--
 include/rc522.h             |  8 +++++++-
 src/rc522.c                 | 23 +++++------------------
 4 files changed, 18 insertions(+), 23 deletions(-)

diff --git a/examples/basic/main/basic.c b/examples/basic/main/basic.c
index eccec3e1..b0ce5e2e 100644
--- a/examples/basic/main/basic.c
+++ b/examples/basic/main/basic.c
@@ -1,5 +1,4 @@
 #include <esp_log.h>
-#include <inttypes.h>
 #include <driver/spi_master.h>
 #include "rc522.h"
 
@@ -67,8 +66,10 @@ static void rc522_event_handler(void *arg, esp_event_base_t base, int32_t event_
 
     switch (event_id) {
         case RC522_EVENT_TAG_SCANNED: {
+            ESP_LOGI(TAG, "Tag scanned!");
+
             rc522_tag_t *tag = (rc522_tag_t *)data->ptr;
-            ESP_LOGI(TAG, "Tag scanned (UID: 0x%" PRIX64 ")", tag->uid);
+            ESP_LOG_BUFFER_HEX(TAG, tag->uid.bytes, tag->uid.length);
         } break;
     }
 }
diff --git a/examples/i2c/main/i2c.c b/examples/i2c/main/i2c.c
index f7a2b388..968d1a65 100644
--- a/examples/i2c/main/i2c.c
+++ b/examples/i2c/main/i2c.c
@@ -1,5 +1,4 @@
 #include <esp_log.h>
-#include <inttypes.h>
 #include <driver/i2c.h>
 #include "rc522.h"
 
@@ -48,8 +47,10 @@ static void rc522_event_handler(void *arg, esp_event_base_t base, int32_t event_
 
     switch (event_id) {
         case RC522_EVENT_TAG_SCANNED: {
+            ESP_LOGI(TAG, "Tag scanned!");
+
             rc522_tag_t *tag = (rc522_tag_t *)data->ptr;
-            ESP_LOGI(TAG, "Tag scanned (UID: 0x%" PRIX64 ")", tag->uid);
+            ESP_LOG_BUFFER_HEX(TAG, tag->uid.bytes, tag->uid.length);
         } break;
     }
 }
diff --git a/include/rc522.h b/include/rc522.h
index a81cd9ae..12cfe36b 100644
--- a/include/rc522.h
+++ b/include/rc522.h
@@ -41,7 +41,13 @@ typedef struct
 
 typedef struct
 {
-    uint64_t uid;
+    uint8_t *bytes;
+    uint8_t length;
+} rc522_tag_uid_t;
+
+typedef struct
+{
+    rc522_tag_uid_t uid;
 } rc522_tag_t;
 
 /**
diff --git a/src/rc522.c b/src/rc522.c
index 5ccb2db6..1a6549a1 100644
--- a/src/rc522.c
+++ b/src/rc522.c
@@ -209,21 +209,6 @@ esp_err_t rc522_unregister_events(rc522_handle_t rc522, rc522_event_t event, esp
     return esp_event_handler_unregister_with(rc522->event_handle, RC522_EVENTS, event, event_handler);
 }
 
-static uint64_t rc522_uid_to_u64(uint8_t *sn)
-{
-    uint64_t result = 0;
-
-    if (!sn) {
-        return 0;
-    }
-
-    for (int i = 4; i >= 0; i--) {
-        result |= ((uint64_t)sn[i] << (i * 8));
-    }
-
-    return result;
-}
-
 // Buffer should be length of 2, or more
 // Only first 2 elements will be used where the result will be stored
 // TODO: Use 2+ bytes data type instead of buffer array
@@ -594,11 +579,13 @@ static void rc522_task(void *arg)
             rc522->tag_was_present_last_time = false;
         }
         else if (!rc522->tag_was_present_last_time) {
-            rc522_tag_t tag = {
-                .uid = rc522_uid_to_u64(uid_bytes),
+            rc522_tag_uid_t uid = {
+                .bytes = uid_bytes,
+                .length = 5, // TODO: Change once when we dynamicaly find the length of UID
             };
-            FREE(uid_bytes);
+            rc522_tag_t tag = { .uid = uid };
             rc522_dispatch_event(rc522, RC522_EVENT_TAG_SCANNED, &tag);
+            FREE(uid_bytes);
             rc522->tag_was_present_last_time = true;
         }
         else {