From f8fc2723da7c61728955b3147dca478620a86b76 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Xose=20P=C3=A9rez?= <xose.perez@gmail.com>
Date: Thu, 26 Oct 2017 12:18:42 +0200
Subject: [PATCH] Dynamically allocate memory for MedianFilter

---
 code/espurna/config/general.h |  7 ------
 code/espurna/power.h          | 47 +++++++++++++++++++----------------
 code/espurna/power.ino        |  8 +++---
 3 files changed, 29 insertions(+), 33 deletions(-)

diff --git a/code/espurna/config/general.h b/code/espurna/config/general.h
index 2cd263ef..757b8994 100644
--- a/code/espurna/config/general.h
+++ b/code/espurna/config/general.h
@@ -556,7 +556,6 @@ PROGMEM const char* const custom_reset_string[] = {
 #define POWER_VOLTAGE                   230     // Default voltage
 #define POWER_READ_INTERVAL             6000    // Default reading interval (6 seconds)
 #define POWER_REPORT_INTERVAL           60000   // Default report interval (1 minute)
-#define POWER_REPORT_BUFFER             12      // Default buffer size ()
 #define POWER_CURRENT_DECIMALS          2       // Decimals for current values
 #define POWER_VOLTAGE_DECIMALS          0       // Decimals for voltage values
 #define POWER_POWER_DECIMALS            0       // Decimals for power values
@@ -596,9 +595,6 @@ PROGMEM const char* const custom_reset_string[] = {
 
 #if POWER_PROVIDER == POWER_PROVIDER_V9261F
 
-    #undef POWER_REPORT_BUFFER
-    #define POWER_REPORT_BUFFER         60      // Override median buffer size
-
     #ifndef V9261F_PIN
     #define V9261F_PIN                  2       // TX pin from the V9261F
     #endif
@@ -619,9 +615,6 @@ PROGMEM const char* const custom_reset_string[] = {
 
 #if POWER_PROVIDER == POWER_PROVIDER_ECH1560
 
-    #undef POWER_REPORT_BUFFER
-    #define POWER_REPORT_BUFFER         60      // Override median buffer size
-
     #ifndef ECH1560_CLK_PIN
     #define ECH1560_CLK_PIN             4       // Default CLK pin
     #endif
diff --git a/code/espurna/power.h b/code/espurna/power.h
index 2c1a786a..1284a3b2 100644
--- a/code/espurna/power.h
+++ b/code/espurna/power.h
@@ -8,36 +8,41 @@ class MedianFilter {
 
     public:
 
-        MedianFilter(unsigned char size) {
-            _size = size;
-            _data = new double[_size+1];
-            reset();
+        MedianFilter() {
+            _data = new std::vector<double>();
+        }
+
+        ~MedianFilter() {
+            if (_data) delete _data;
         }
 
         virtual void reset() {
-            if (_pointer > 1) _data[0] = _data[_pointer-1];
-            _pointer = 1;
-            for (unsigned char i=1; i<=_size; i++) _data[i] = 0;
+            double last = _data->empty() ? 0 : _data->back();
+            _data->clear();
+            add(last);
         }
 
         virtual void add(double value) {
-            if (_pointer <= _size) {
-                _data[_pointer] = value;
-                ++_pointer;
-            }
+            _data->push_back(value);
         }
 
-        virtual double average(bool do_reset = false) {
+        virtual double median(bool do_reset = false) {
 
             double sum = 0;
 
-            if (_pointer > 2) {
+            if (_data->size() == 1) {
+                sum = _data->back();
+
+            } else if (_data->size() == 2) {
+                sum = _data->front();
+
+            } else if (_data->size() > 2) {
 
-                for (unsigned char i = 1; i<_pointer-1; i++) {
+                for (unsigned char i = 1; i <= _data->size() - 2; i++) {
 
-                    double previous = _data[i-1];
-                    double current = _data[i];
-                    double next = _data[i+1];
+                    double previous = _data->at(i-1);
+                    double current = _data->at(i);
+                    double next = _data->at(i+1);
 
                     if (previous > current) std::swap(previous, current);
                     if (current > next) std::swap(current, next);
@@ -47,7 +52,7 @@ class MedianFilter {
 
                 }
 
-                sum /= (_pointer - 2);
+                sum /= (_data->size() - 2);
 
             }
 
@@ -58,13 +63,11 @@ class MedianFilter {
         }
 
         virtual unsigned char count() {
-            return _pointer - 1;
+            return _data->size();
         }
 
     private:
 
-        double *_data;
-        unsigned char _size = 0;
-        unsigned char _pointer = 0;
+        std::vector<double> *_data;
 
 };
diff --git a/code/espurna/power.ino b/code/espurna/power.ino
index b6752ebd..1651d858 100644
--- a/code/espurna/power.ino
+++ b/code/espurna/power.ino
@@ -24,15 +24,15 @@ double _power_current = 0;
 double _power_voltage = 0;
 double _power_apparent = 0;
 double _power_energy = 0;
-MedianFilter _filter_current = MedianFilter(POWER_REPORT_BUFFER);
+MedianFilter _filter_current = MedianFilter();
 
 #if POWER_HAS_ACTIVE
     double _power_active = 0;
     double _power_reactive = 0;
     double _power_factor = 0;
-    MedianFilter _filter_voltage = MedianFilter(POWER_REPORT_BUFFER);
-    MedianFilter _filter_active = MedianFilter(POWER_REPORT_BUFFER);
-    MedianFilter _filter_apparent = MedianFilter(POWER_REPORT_BUFFER);
+    MedianFilter _filter_voltage = MedianFilter();
+    MedianFilter _filter_active = MedianFilter();
+    MedianFilter _filter_apparent = MedianFilter();
 #endif
 
 #if POWER_HAS_ENERGY