#include "CommandBuff.h"
#include <algorithm>

USING_NS_CC;
#define EVENT_AFTER_DRAW_RESET_POSITION "director_after_draw"
using std::max;
#define INITIAL_SIZE (10000)

static CommandBuff* instance = nullptr;

CommandBuff* CommandBuff::getInstance () {
	if (!instance) instance = new CommandBuff();
	return instance;
}

void CommandBuff::destroyInstance () {
	if (instance) {
		delete instance;
		instance = nullptr;
	}
}

CommandBuff::CommandBuff () {
	for (unsigned int i = 0; i < INITIAL_SIZE; i++) {
		_commandsPool.push_back(new TrianglesCommand());
	}

	reset ();

	// callback after drawing is finished so we can clear out the batch state
	// for the next frame
	Director::getInstance()->getEventDispatcher()->addCustomEventListener(EVENT_AFTER_DRAW_RESET_POSITION, [this](EventCustom* eventCustom){
		this->update(0);
	});;
}

CommandBuff::~CommandBuff () {
	Director::getInstance()->getEventDispatcher()->removeCustomEventListeners(EVENT_AFTER_DRAW_RESET_POSITION);

	for (unsigned int i = 0; i < _commandsPool.size(); i++) {
		delete _commandsPool[i];
		_commandsPool[i] = nullptr;
	}
}

void CommandBuff::update (float delta) {
	reset();
}

cocos2d::TrianglesCommand* CommandBuff::addCommand(cocos2d::Renderer* renderer, float globalOrder, cocos2d::Texture2D* texture, cocos2d::GLProgramState* glProgramState, cocos2d::BlendFunc blendType, const cocos2d::TrianglesCommand::Triangles& triangles, const cocos2d::Mat4& mv, uint32_t flags) {
	TrianglesCommand* command = nextFreeCommand();
	command->init(globalOrder, texture, glProgramState, blendType, triangles, mv, flags);
	renderer->addCommand(command);
	return command;
}

void CommandBuff::reset() {
	_nextFreeCommand = 0;
}

cocos2d::TrianglesCommand* CommandBuff::nextFreeCommand() {
	if (_commandsPool.size() <= _nextFreeCommand) {
		auto newSize = _commandsPool.size() * 2 + 1;
		for (auto i = _commandsPool.size(); i < newSize; i++) {
			_commandsPool.push_back(new TrianglesCommand());
		}
	}
	return _commandsPool[_nextFreeCommand++];
}