Enhance CAN decoding with advanced features and analytics.

src/can_decode.c

@@ -1,17 +1,141 @@
 #include "can_decode.h"
 #include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <time.h>
+
+#define MAX_TEMP 150
+#define MAX_SPEED 300
+#define BATTERY_VOLTAGE_FACTOR 0.1
+#define RPM_FACTOR 10
+#define ACCELERATION_FACTOR 0.01
+#define TIRE_PRESSURE_FACTOR 0.1
+#define OIL_PRESSURE_FACTOR 0.1
+#define FUEL_CONSUMPTION_FACTOR 0.1
+
+// Function prototypes
+double calculate_moving_average(double *values, int window_size);
+int detect_anomaly(double value, double mean, double std_dev);
+double calculate_standard_deviation(double *values, int count);
+
+// Circular buffer for storing historical values
+#define HISTORY_SIZE 100
+double temperature_history[HISTORY_SIZE] = {0};
+double speed_history[HISTORY_SIZE] = {0};
+int history_index = 0;
 
 void decode_can_message(const struct can_frame *frame) {
     printf("Decoded message: ");
 
     switch (frame->can_id) {
         case 0x123:
-            printf("Engine Temperature: %d°C\n", frame->data[0]);
+            {
+                int temp = frame->data[0];
+                printf("Engine Temperature: %d°C\n", temp);
+
+                // Store in circular buffer
+                temperature_history[history_index] = temp;
+
+                // Calculate moving average
+                double avg_temp = calculate_moving_average(temperature_history, HISTORY_SIZE);
+                printf("Average Temperature (last %d readings): %.2f°C\n", HISTORY_SIZE, avg_temp);
+
+                // Anomaly detection
+                double std_dev = calculate_standard_deviation(temperature_history, HISTORY_SIZE);
+                if (detect_anomaly(temp, avg_temp, std_dev)) {
+                    printf("WARNING: Anomalous temperature detected!\n");
+                }
+
+                // Temperature rate of change
+                static double last_temp = 0;
+                static time_t last_time = 0;
+                time_t current_time = time(NULL);
+                if (last_time != 0) {
+                    double temp_rate = (temp - last_temp) / difftime(current_time, last_time);
+                    printf("Temperature Rate of Change: %.2f°C/s\n", temp_rate);
+                }
+                last_temp = temp;
+                last_time = current_time;
+            }
             break;
         case 0x456:
-            printf("Vehicle Speed: %d km/h\n", frame->data[0]);
+            {
+                int speed = frame->data[0];
+                printf("Vehicle Speed: %d km/h\n", speed);
+
+                // Store in circular buffer
+                speed_history[history_index] = speed;
+
+                // Calculate moving average
+                double avg_speed = calculate_moving_average(speed_history, HISTORY_SIZE);
+                printf("Average Speed (last %d readings): %.2f km/h\n", HISTORY_SIZE, avg_speed);
+            }
+            break;
+        case 0x789:
+            {
+                int battery_voltage = (frame->data[0] << 8 | frame->data[1]) * BATTERY_VOLTAGE_FACTOR;
+                printf("Battery Voltage: %.1f V\n", battery_voltage / 10.0);
+            }
+            break;
+        case 0xABC:
+            {
+                int rpm = (frame->data[0] << 8 | frame->data[1]) * RPM_FACTOR;
+                printf("Engine RPM: %d\n", rpm);
+            }
+            break;
+        case 0xDEF:
+            {
+                int16_t acceleration = (frame->data[0] << 8 | frame->data[1]);
+                printf("Vehicle Acceleration: %.2f m/s^2\n", acceleration * ACCELERATION_FACTOR);
+            }
+            break;
+        case 0x321:
+            {
+                for (int i = 0; i < 4; i++) {
+                    printf("Tire Pressure %d: %.1f PSI\n", i+1, frame->data[i] * TIRE_PRESSURE_FACTOR);
+                }
+            }
+            break;
+        case 0x654:
+            {
+                int oil_pressure = (frame->data[0] << 8 | frame->data[1]) * OIL_PRESSURE_FACTOR;
+                printf("Oil Pressure: %.1f PSI\n", oil_pressure / 10.0);
+            }
+            break;
+        case 0x987:
+            {
+                int fuel_consumption = (frame->data[0] << 8 | frame->data[1]) * FUEL_CONSUMPTION_FACTOR;
+                printf("Fuel Consumption: %.1f L/100km\n", fuel_consumption / 10.0);
+            }
             break;
         default:
             printf("Unknown message type\n");
     }
+
+    history_index = (history_index + 1) % HISTORY_SIZE;
+}
+
+double calculate_moving_average(double *values, int window_size) {
+    double sum = 0;
+    for (int i = 0; i < window_size; i++) {
+        sum += values[i];
+    }
+    return sum / window_size;
+}
+
+int detect_anomaly(double value, double mean, double std_dev) {
+    return fabs(value - mean) > 3 * std_dev;
+}
+
+double calculate_standard_deviation(double *values, int count) {
+    double sum = 0, mean, std_dev = 0;
+    int i;
+    for (i = 0; i < count; ++i) {
+        sum += values[i];
+    }
+    mean = sum / count;
+    for (i = 0; i < count; ++i) {
+        std_dev += pow(values[i] - mean, 2);
+    }
+    return sqrt(std_dev / count);
 }