From cfbd22d259fa8df2e1d7dd16dcb4d392c2ff0b18 Mon Sep 17 00:00:00 2001
From: Pieter Hollander <git@pieterhollander.nl>
Date: Sun, 18 Feb 2024 17:56:06 +0100
Subject: [PATCH] Add debugging code for update only on change.

---
 main.go | 52 +++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 43 insertions(+), 9 deletions(-)

diff --git a/main.go b/main.go
index 9ffb0c7..72c8d93 100644
--- a/main.go
+++ b/main.go
@@ -119,14 +119,24 @@ func main() {
 
 var prevDt1, prevDt2, prevRt1, prevRt2, prevG int
 
-func updateFieldIfChanged(currentValue *int, previousValue *int) *int {
+// func updateFieldIfChanged(currentValue *int, previousValue *int) *int {
+// 	if currentValue != nil && *currentValue == *previousValue {
+// 		return nil // No change, so we prepare to insert a NULL
+// 	} else if currentValue != nil {
+// 		*previousValue = *currentValue // Update the previous value to the current one
+// 		return currentValue
+// 	}
+// 	return currentValue // Return the original value if it's nil
+// }
+
+func updateFieldIfChanged(currentValue *int, previousValue *int) (*int, bool) {
 	if currentValue != nil && *currentValue == *previousValue {
-		return nil // No change, so we prepare to insert a NULL
+		return nil, false // No change
 	} else if currentValue != nil {
 		*previousValue = *currentValue // Update the previous value to the current one
-		return currentValue
+		return currentValue, true      // Change occurred
 	}
-	return currentValue // Return the original value if it's nil
+	return currentValue, false // Return the original value if it's nil, indicating no change
 }
 
 func mqttMessageHandler(client mqtt.Client, msg mqtt.Message) {
@@ -145,12 +155,36 @@ func mqttMessageHandler(client mqtt.Client, msg mqtt.Message) {
 		return
 	}
 
-	payload.Dt1 = updateFieldIfChanged(payload.Dt1, &prevDt1)
-	payload.Dt2 = updateFieldIfChanged(payload.Dt2, &prevDt2)
-	payload.Rt1 = updateFieldIfChanged(payload.Rt1, &prevRt1)
-	payload.Rt2 = updateFieldIfChanged(payload.Rt2, &prevRt2)
-	payload.G = updateFieldIfChanged(payload.G, &prevG)
+	// payload.Dt1 = updateFieldIfChanged(payload.Dt1, &prevDt1)
+	// payload.Dt2 = updateFieldIfChanged(payload.Dt2, &prevDt2)
+	// payload.Rt1 = updateFieldIfChanged(payload.Rt1, &prevRt1)
+	// payload.Rt2 = updateFieldIfChanged(payload.Rt2, &prevRt2)
+	// payload.G = updateFieldIfChanged(payload.G, &prevG)
 
+	var changed bool // Flag to track if any value changed
+
+	// Update each field, directly updating `changed` if any change is detected
+	var tempChanged bool // Used to capture the change status for each field
+	payload.Dt1, tempChanged = updateFieldIfChanged(payload.Dt1, &prevDt1)
+	changed = changed || tempChanged
+
+	payload.Dt2, tempChanged = updateFieldIfChanged(payload.Dt2, &prevDt2)
+	changed = changed || tempChanged
+
+	payload.Rt1, tempChanged = updateFieldIfChanged(payload.Rt1, &prevRt1)
+	changed = changed || tempChanged
+
+	payload.Rt2, tempChanged = updateFieldIfChanged(payload.Rt2, &prevRt2)
+	changed = changed || tempChanged
+
+	payload.G, tempChanged = updateFieldIfChanged(payload.G, &prevG)
+	changed = changed || tempChanged
+
+	// If any value has changed, log all the relevant values
+	if changed {
+		log.Printf("Values changed: dt1=%v, dt2=%v, rt1=%v, rt2=%v, g=%v\n",
+			payload.Dt1, payload.Dt2, payload.Rt1, payload.Rt2, payload.G)
+	}
 	// Insert data into PostgreSQL
 	err = insertData(timestamp, payload)
 	if err != nil {