#include "PipeLine.h"
#include "logger.h"

PipeMaterial::PipeMaterial() : 
	type(PMT__FIRST), buffer(nullptr), buffSize(0), 
	former(nullptr), deleter(nullptr), args(nullptr)
{
}

void PipeMaterial::exec_deleter()
{
	if (deleter != nullptr)
	{
		deleter(this);
		deleter = nullptr;
	}
}

PipeLine::PipeLine() : global_params_map(), elem_create_func_map(), elems()
{
}

PipeLine::~PipeLine()
{
	// pipe stop
	
	for(elem_vec_t::iterator iter = elems.begin(); iter != elems.end(); ++iter)
	{
		PipeLineElem* elem = *iter;
		if (elem != nullptr)
		{
			elem->finit();
			delete *iter;
		}
	}
	
	elems.clear();
}

bool PipeLine::register_elem_creator(const std::string& type, elem_create_func_t func)
{
	if (type.empty() || func == nullptr)
		return false;

	elem_create_func_map_t::iterator iter = elem_create_func_map.find(type);
	if (iter != elem_create_func_map.end())
		return false;
	
	elem_create_func_map.insert(std::make_pair(type, func));
	return true;
}

void PipeLine::push_elem(PipeLineElem* elem)
{
	if(elem != nullptr)
	{
		elem->manager = this;
		elems.push_back(elem);
	}
}

PipeLineElem* PipeLine::push_elem(const std::string& type)
{
	elem_create_func_map_t::iterator iter = elem_create_func_map.find(type);
	if (iter == elem_create_func_map.end())
		return nullptr;
	
	elem_create_func_t func = iter->second;
	if (func == nullptr)
		return nullptr;
	
	PipeLineElem* elem = func();
	if (elem == nullptr)
		return nullptr;
	
	elem->manager = this;
	push_elem(elem);
	return elem;
}

class PipeDebugger
{
private:
	PipeLine* pipeLine;

public:
	PipeLineElem* retElem;
	PipeMaterial* pm;

	PipeDebugger(PipeLine* _pipeLine) : 
		pipeLine(_pipeLine), retElem(nullptr), pm(nullptr)
	{
		LOG(DEBUG) << "pipe line begin";
	}
	
	~PipeDebugger()
	{
		bool retOK = (*(pipeLine->elems).rbegin() == retElem);
		if (retOK)
			LOG(DEBUG) << "pipe line end, ret OK";
		else
			LOG(WARN) << "pipe line end, ret ERROR";
	}
};

PipeLineElem* PipeLine::pipe(PipeMaterial* pm /*= nullptr*/)
{
	PipeDebugger debugger(this);
	
	PipeLineElem* elem_begin = *elems.begin();
	PipeLineElem* elem_last = *elems.rbegin();

	if (elems.empty() || elem_begin == nullptr || elem_last == nullptr)
		return nullptr;

	uint8_t pmPlacement[sizeof(PipeMaterial)];
	if (pm == nullptr)
		pm = new (pmPlacement) PipeMaterial;
	
	debugger.pm = pm;

	if (elems.size() == 1)
	{
		elem_begin->gain(*pm);
		pm->exec_deleter();
		return debugger.retElem = elem_begin;
	}
	else if (elems.size() == 2)
	{
		if (elem_begin->gain(*pm))
		{
			elem_last->pay(*pm);
			pm->exec_deleter();
		}
		else
			return debugger.retElem = elem_begin;
		return debugger.retElem = elem_last;
	}
	else
	{
		if (!elem_begin->gain(*pm))
			return debugger.retElem = elem_begin;
		
		bool lastRet = true;
		elem_vec_t::iterator iter = elems.begin();
		++iter;
		elem_begin = *iter;
		while (elem_begin != elem_last)
		{
			if (lastRet && (lastRet = elem_begin->pay(*pm)) )
			{
				pm->exec_deleter();
				lastRet = elem_begin->gain(*pm);
			}
			else
				return debugger.retElem = elem_begin;
			
			++iter;
			elem_begin = *iter;
		}
	
		if (lastRet)
		{
			elem_last->pay(*pm);
			pm->exec_deleter();
		}
		return debugger.retElem = elem_last;
	}
	
	return nullptr;
}

void PipeLine::set_global_param(const std::string& name, const std::string& value)
{
	if (name.empty())
		return;

	global_params_map_t::iterator iter = global_params_map.find(name);
	if (iter == global_params_map.end())
		global_params_map.insert(std::make_pair(name, value));
	else
		iter->second = value;
}

std::string PipeLine::get_global_param(const std::string& name) const
{
	global_params_map_t::const_iterator iter = global_params_map.find(name);
	if (iter == global_params_map.end())
		return "";
	else
		return iter->second;
}