I2CReceiver.h

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#ifndef I2CReceiver_h
#define I2CReceiver_h
 
#include "ReelTwo.h"
#include "core/AnimatedEvent.h"
#include "core/CommandEvent.h"
#include <Wire.h>
 
template<int bufferSize = 32>
class I2CReceiverBase : public AnimatedEvent
{
public:
    I2CReceiverBase(void (*callback)(char*) = nullptr) :
        fCallback(callback)
    {
        *myself() = this;
    #if !defined(ESP32) || (defined(ESP_ARDUINO_VERSION_MAJOR) && ESP_ARDUINO_VERSION_MAJOR >= 2)
        Wire.onReceive(i2cEvent);                // Register event so when we receive something we jump to i2cEvent();
    #else
        #warning NOTE: I2C receiver will not work. Upgrade to version 2.0.4
    #endif
    }
 
    I2CReceiverBase(byte i2caddress, void (*callback)(char*) = nullptr) :
        fCallback(callback)
    {
        *myself() = this;
    #if !defined(ESP32) || (defined(ESP_ARDUINO_VERSION_MAJOR) && ESP_ARDUINO_VERSION_MAJOR >= 2)
        Wire.onReceive(i2cEvent);                // Register event so when we receive something we jump to i2cEvent();
    #else
        #warning NOTE: I2C receiver will not work. Upgrade to version 2.0.4
    #endif
        begin(i2caddress);
    }
 
    void begin(byte i2caddress = 0x19)
    {
        Wire.begin(i2caddress);                  // Connects to I2C Bus and establishes address.
    }
 
    virtual void animate() override
    {
        if (fCmdReady && *fCmdString != 0)
        {
            if (fCmdString[1] == 0 && fCmdString[0] >= 0 && fCmdString[0] <= 9)
            {
                fCmdString[0] += '0';
            }
            if (fCallback != nullptr)
            {
                fCallback(fCmdString);
            }
            else
            {
                CommandEvent::process(fCmdString);
            }
        }
        fCmdReady = false;
    }
 
private:
    char fCmdString[bufferSize];
    volatile bool fCmdReady = false;
    void (*fCallback)(char*) = nullptr;
 
    void handleEvent(int howMany)
    {
        UNUSED_ARG(howMany)
        /* ignore any new i2c event until previous one has been processed */
        if (fCmdReady)
            return;
        for (byte i = 0; Wire.available();)
        {
            char ch = (char)Wire.read();
            // Dont add leading whitespace
            if (i < sizeof(fCmdString) - 1 && (i != 0 || !isspace(ch)))
            {
                fCmdString[i++] = (ch != '\r') ? ch : '\n';
                fCmdString[i] = 0;
            }
        }
        // DEBUG_PRINTLN(fCmdString);
        fCmdReady = true;
    }
 
    static void i2cEvent(int howMany)
    {
        (*myself())->handleEvent(howMany);
    }
 
    static I2CReceiverBase<bufferSize>** myself()
    {
        static I2CReceiverBase<bufferSize>* self;
        return &self;
    }
 
    static constexpr bool sCreated = false;
};
 
typedef I2CReceiverBase<> I2CReceiver;
#endif