#include "LedDeviceLpd6803.h"

LedDeviceLpd6803::LedDeviceLpd6803(const Json::Value &deviceConfig)
	: ProviderSpi(deviceConfig)
{
}

LedDevice* LedDeviceLpd6803::construct(const Json::Value &deviceConfig)
{
	return new LedDeviceLpd6803(deviceConfig);
}

int LedDeviceLpd6803::write(const std::vector<ColorRgb> &ledValues)
{
	unsigned messageLength = 4 + 2*_ledCount + _ledCount/8 + 1;
	// Reconfigure if the current connfiguration does not match the required configuration
	if (messageLength != _ledBuffer.size())
	{
		// Initialise the buffer
		_ledBuffer.resize(messageLength, 0x00);
	}

	// Copy the colors from the ColorRgb vector to the Ldp6803 data vector
	for (unsigned iLed=0; iLed<(unsigned)_ledCount; ++iLed)
	{
		const ColorRgb& rgb = ledValues[iLed];

		_ledBuffer[4 + 2 * iLed] = 0x80 | ((rgb.red & 0xf8) >> 1) | (rgb.green >> 6);
		_ledBuffer[5 + 2 * iLed] = ((rgb.green & 0x38) << 2) | (rgb.blue >> 3);
	}

	// Write the data
	return (writeBytes(_ledBuffer.size(), _ledBuffer.data()) < 0) ? -1 : 0;
}