added comments

plugins/dynpow/pow.go

@@ -75,21 +75,26 @@ func DoPOW(msg []byte) (uint64, error) {
 	return nonce, err
 }
 
+// Function to adjust the PoW difficulty, called on the reception of a mesasage.
+// Takes a *tangle.Message as parameter, and returns the next difficulty to account.
 func adjustDifficulty(message *tangle.Message) int {
-	//TODO dire que c'est fait
+	// We use a global variable to track the transaction solidication time
 	prevSolidificationTime := currentSolidificationTime
-	currentSolidificationTime = time.Now().UnixNano() - message.IssuingTime().UnixNano()
 
-	deltat := currentSolidificationTime - prevSolidificationTime
+	currentSolidificationTime = time.Now().UnixNano() - message.IssuingTime().UnixNano() //We calculate the message solidication time?
 
-	powIncrement := int(deltat / 600000)
+	deltat := currentSolidificationTime - prevSolidificationTime // deltat tracks the evolution of solidification time (if it increases, deltat is positive, negative if decrease). Unit is nanoseconds
 
+	powIncrement := int(deltat / 600000) //We use this time difference to directly calculate the PoW (if it increases, POW difficulty increases)
+
+	// If/else block to cap the PoW difficulty between 1 & 10.
 	if difficulty+powIncrement > 10 {
 		return 10
 	} else if difficulty+powIncrement < 1 {
 		return 1
 	}
 
+	// We return current difficulty (global variable) plus the increment calculated previously (positive if solidication time increases, negative otherwise).
 	return difficulty + powIncrement
 
 }