Add setValidValues(int n, ...) method to Characteristic

Allows user to explicitly set the valid values for a Characteristic of type UINT8.  Throws an error if used with any other Characteristic type.

src/HomeSpan.cpp

@@ -1600,6 +1600,10 @@ int SpanCharacteristic::sprintfAttributes(char *cBuf, int flags){
       if(uvGet<float>(stepValue)>0)
         nBytes+=snprintf(cBuf?(cBuf+nBytes):NULL,cBuf?128:0,",\"minStep\":%s",uvPrint(stepValue).c_str());
     }
+
+    if(validValues){
+      nBytes+=snprintf(cBuf?(cBuf+nBytes):NULL,cBuf?128:0,",\"valid-values\":%s",validValues);      
+    }
   }
     
   if(desc && (flags&GET_DESC)){
@@ -1720,6 +1724,40 @@ unsigned long SpanCharacteristic::timeVal(){
   return(homeSpan.snapTime-updateTime);
 }
 
+///////////////////////////////
+
+void SpanCharacteristic::setValidValues(int n, ...){
+  char c[256];
+  String *s = new String("[");
+  va_list vl;
+  va_start(vl,n);
+  for(int i=0;i<n;i++){
+    *s+=va_arg(vl,int);
+    if(i!=n-1)
+      *s+=",";
+  }
+  va_end(vl);
+  *s+="]";
+
+  homeSpan.configLog+=String("         \u2b0c Set Valid Values for ") + String(hapName) + " with IID=" + String(iid);
+
+  if(validValues){
+    sprintf(c,"  *** ERROR!  Valid Values already set for this Characteristic! ***\n");
+    homeSpan.nFatalErrors++;
+  } else 
+
+  if(format!=UINT8){
+    sprintf(c,"  *** ERROR!  Can't set Valid Values for this Characteristic! ***\n");
+    homeSpan.nFatalErrors++;      
+  } else {
+    
+    validValues=s->c_str();
+    sprintf(c,":  ValidValues=%s\n",validValues);
+  }
+
+  homeSpan.configLog+=c;
+}
+
 ///////////////////////////////
 //        SpanRange          //
 ///////////////////////////////

src/HomeSpan.h

@@ -256,8 +256,9 @@ struct SpanCharacteristic{
   UVal minValue;                           // Characteristic minimum (not applicable for STRING)
   UVal maxValue;                           // Characteristic maximum (not applicable for STRING)
   UVal stepValue;                          // Characteristic step size (not applicable for STRING)
-  boolean staticRange;                     // Flag that indiates whether Range is static and cannot be changed with setRange()
+  boolean staticRange;                     // Flag that indicates whether Range is static and cannot be changed with setRange()
   boolean customRange=false;               // Flag for custom ranges
+  const char *validValues=NULL;            // Optional JSON array of valid values.  Applicable only to uint8 Characteristics
   boolean *ev;                             // Characteristic Event Notify Enable (per-connection)
   char *nvsKey=NULL;                       // key for NVS storage of Characteristic value
   
@@ -274,6 +275,7 @@ struct SpanCharacteristic{
   
   boolean updated(){return(isUpdated);}           // returns isUpdated
   unsigned long timeVal();                        // returns time elapsed (in millis) since value was last updated
+  void setValidValues(int n, ...);                // sets a list of 'n' valid values allowed for a Characteristic.  Only applicable if format=uint8
     
   String uvPrint(UVal &u){
     char c[64];

src/Span.h

@@ -381,7 +381,7 @@ namespace Service {
 // SPAN CHARACTERISTICS (HAP Chapter 9) //
 //////////////////////////////////////////
 
-// Macro to define Span Characteristic structures based on name of HAP Characteristic, default value, and mix/max value (not applicable for STRING or BOOL which default to min=0, max=1)
+// Macro to define Span Characteristic structures based on name of HAP Characteristic, default value, and min/max value (not applicable for STRING or BOOL which default to min=0, max=1)
 
 #define CREATE_CHAR(TYPE,HAPCHAR,DEFVAL,MINVAL,MAXVAL) \
   struct HAPCHAR : SpanCharacteristic { HAPCHAR(TYPE val=DEFVAL, boolean nvsStore=false) : SpanCharacteristic {&hapChars.HAPCHAR} { init(val,nvsStore,(TYPE)MINVAL,(TYPE)MAXVAL); } };