Berry `scale_int`, equivalent of `scale_uint` for signed integers (#20090)

CHANGELOG.md

@@ -12,6 +12,7 @@ All notable changes to this project will be documented in this file.
 - NeoPool store settings on unified file system (#19973)
 - NeoPool command ``NPBoost`` (#19973)
 - ESP32 Partition Wizard can be loaded dynamically (#19980)
+- Berry `scale_int`, equivalent of `scale_uint` for signed integers
 
 ### Breaking Changed
 

lib/libesp32/berry_tasmota/src/be_tasmota_lib.c

@@ -34,6 +34,7 @@ extern int l_yield(bvm *vm);
 extern int l_delay(bvm *vm);
 extern int l_delay_microseconds(bvm *vm);
 extern int l_scaleuint(bvm *vm);
+extern int l_scaleint(bvm *vm);
 extern int l_logInfo(bvm *vm);
 extern int l_loglevel(bvm *vm);
 extern int l_save(bvm *vm);
@@ -118,6 +119,7 @@ class be_class_tasmota (scope: global, name: Tasmota) {
     delay, func(l_delay)
     delay_microseconds, func(l_delay_microseconds)
     scale_uint, static_func(l_scaleuint)
+    scale_int, static_func(l_scaleint)
     log, func(l_logInfo)
     loglevel, func(l_loglevel)
     save, func(l_save)

tasmota/tasmota_support/support_float.ino

@@ -376,8 +376,8 @@ float sqrt1(const float x)
 //
 // New version, you don't need the "to_min < to_max" precondition anymore
 //
-// PRE-CONDITIONS (if not satisfied, you may 'halt and catch fire')
-//    from_min < from_max  (not checked)
+// PRE-CONDITIONS (if not satisfied, returns the smallest between to_min and to_max')
+//    from_min < from_max  (checked)
 //    from_min <= num <= from_max  (checked)
 // POST-CONDITIONS
 //    to_min <= result <= to_max
@@ -427,6 +427,38 @@ uint16_t changeUIntScale(uint16_t inum, uint16_t ifrom_min, uint16_t ifrom_max,
   return (uint32_t) (result > to_max ? to_max : (result < to_min ? to_min : result));
 }
 
+//
+// changeIntScale
+// Change a value for range a..b to c..d, for signed ints (16 bits max to avoid overflow)
+//
+// PRE-CONDITIONS (if not satisfied, returns the smallest between to_min and to_max')
+//    from_min < from_max  (checked)
+//    from_min <= num <= from_max  (checked)
+// POST-CONDITIONS
+//    to_min <= result <= to_max
+//
+int16_t changeIntScale(int16_t num, int16_t from_min, int16_t from_max,
+                                    int16_t to_min, int16_t to_max) {
+
+  // guard-rails
+  if (from_min >= from_max) {
+    return (to_min > to_max ? to_max : to_min);  // invalid input, return arbitrary value
+  }
+  int32_t from_offset = 0;
+  if (from_min < 0) {
+    from_offset = - from_min;
+  }
+  int32_t to_offset = 0;
+  if (to_min < 0) {
+    to_offset = - to_min;
+  }
+  if (to_max < (- to_offset)) {
+    to_offset = - to_max;
+  }
+
+  return changeUIntScale(num + from_offset, from_min + from_offset, from_max + from_offset, to_min + to_offset, to_max + to_offset) - to_offset;
+}
+
 // Force a float value between two ranges, and adds or substract the range until we fit
 float ModulusRangef(float f, float a, float b) {
   if (b <= a) { return a; }       // inconsistent, do what we can

tasmota/tasmota_xdrv_driver/xdrv_52_3_berry_tasmota.ino

@@ -409,6 +409,24 @@ extern "C" {
     be_raise(vm, kTypeError, nullptr);
   }
 
+  // Berry: tasmota.scale_int(int * 5) -> int
+  //
+  int32_t l_scaleint(struct bvm *vm);
+  int32_t l_scaleint(struct bvm *vm) {
+    int32_t top = be_top(vm); // Get the number of arguments
+    if (top == 5 && be_isint(vm, 1) && be_isint(vm, 2) && be_isint(vm, 3) && be_isint(vm, 4) && be_isint(vm, 5)) {
+      int32_t val = be_toint(vm, 1);
+      int32_t from_min = be_toint(vm, 2);
+      int32_t from_max = be_toint(vm, 3);
+      int32_t to_min = be_toint(vm, 4);
+      int32_t to_max = be_toint(vm, 5);
+      int32_t scaled = changeIntScale(val, from_min, from_max, to_min, to_max);
+      be_pushint(vm, scaled);
+      be_return(vm);
+    }
+    be_raise(vm, kTypeError, nullptr);
+  }
+
   int32_t l_respCmnd(bvm *vm);
   int32_t l_respCmnd(bvm *vm) {
     int32_t top = be_top(vm); // Get the number of arguments