///
/// \author	John Farrier
///
/// \copyright Copyright 2015, 2016, 2017, 2018. 2019 John Farrier
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
/// http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///

#include <celero/Benchmark.h>
#include <celero/Experiment.h>
#include <celero/Factory.h>
#include <celero/PimplImpl.h>
#include <celero/TestFixture.h>
#include <celero/Utilities.h>

#include <algorithm>
#include <cassert>

using namespace celero;

class Experiment::Impl
{
public:
	Impl() :
		results(),
		benchmark(),
		factory(),
		name(),
		baselineUnit(0),
		baselineTarget(0),
		samples(0),
		iterations(0),
		threads(1),
		totalRunTime(0),
		isBaselineCase(false)
	{
	}

	Impl(std::weak_ptr<Benchmark> bm, const std::string& n, const uint64_t s, const uint64_t c, const uint64_t t, const double pBaselineTarget) :
		results(),
		benchmark(bm),
		factory(),
		name(n),
		baselineUnit(0),
		baselineTarget(pBaselineTarget),
		samples(s),
		iterations(c),
		threads(t),
		totalRunTime(0),
		isBaselineCase(false)
	{
	}

	explicit Impl(std::weak_ptr<Benchmark> bm) :
		results(),
		benchmark(bm),
		factory(),
		name(),
		baselineUnit(0),
		baselineTarget(0),
		samples(0),
		iterations(0),
		threads(1),
		totalRunTime(0),
		isBaselineCase(false)
	{
	}

	/// There is one result for each problem space value.
	/// In the event there are not any problem spaces, there shal be a single result.
	std::vector<std::shared_ptr<celero::ExperimentResult>> results;

	/// The owning benchmark object which groups together all experiments.
	std::weak_ptr<Benchmark> benchmark;

	/// The factory to associate with this benchmark.
	std::shared_ptr<Factory> factory;

	/// The name of this experiment.
	std::string name;

	/// The number of microseconds per test (which makes up one baseline unit).
	double baselineUnit{0};

	/// Used to pass/fail benchmarks when outputting JUnit.
	double baselineTarget{0};

	/// Test samples to complete.
	uint64_t samples{0};

	/// Iterations per test run.  (Size of each sample.)
	uint64_t iterations{0};

	/// Threads per test run.
	uint64_t threads{0};

	/// The best run time for this test
	uint64_t totalRunTime{0};

	bool isBaselineCase{false};
};

Experiment::Experiment() : pimpl()
{
}

Experiment::Experiment(std::weak_ptr<Benchmark> benchmark) : pimpl(benchmark)
{
}

Experiment::Experiment(std::weak_ptr<Benchmark> benchmark, const std::string& name, uint64_t samples, uint64_t iterations, uint64_t threads,
					   double baselineTarget) :
	pimpl(benchmark, name, samples, iterations, threads, baselineTarget)
{
}

Experiment::Experiment(const Experiment&)
{
}

Experiment::~Experiment()
{
}

std::shared_ptr<Benchmark> Experiment::getBenchmark()
{
	return this->pimpl->benchmark.lock();
}

void Experiment::setName(const std::string& x)
{
	this->pimpl->name = x;
}

std::string Experiment::getName() const
{
	return this->pimpl->name;
}

void Experiment::setSamples(uint64_t x)
{
	this->pimpl->samples = x;
}

uint64_t Experiment::getSamples() const
{
	return this->pimpl->samples;
}

void Experiment::setIterations(uint64_t x)
{
	this->pimpl->iterations = x;
}

uint64_t Experiment::getIterations() const
{
	return this->pimpl->iterations;
}

void Experiment::setThreads(uint64_t x)
{
	this->pimpl->threads = x;
}

uint64_t Experiment::getThreads() const
{
	return this->pimpl->threads;
}

Experiment::operator std::string() const
{
	auto output = this->getShort();

	if(this->getSamples() > 0)
	{
		output += " -- " + std::to_string(this->getSamples());

		if(this->getSamples() == 1)
		{
			output += " run, ";
		}
		else
		{
			output += " samples, ";
		}
	}
	else
	{
		output += " -- Auto Run, ";
	}

	output += std::to_string(this->getIterations());

	if(this->getIterations() == 1)
	{
		output += " iteration per run,";
	}
	else
	{
		output += " iterations per run,";
	}

	if(this->getThreads() == 1)
	{
		output += " thread per run.";
	}
	else
	{
		output += " threads per run.";
	}

	return output;
}

std::string Experiment::getShort() const
{
	auto bm = this->pimpl->benchmark.lock();

	if(bm != nullptr)
	{
		return bm->getName() + "." + this->getName();
	}

	return this->getName();
}

void Experiment::setBaselineTarget(double x)
{
	this->pimpl->baselineTarget = x;
}

double Experiment::getBaselineTarget() const
{
	return this->pimpl->baselineTarget;
}

void Experiment::incrementTotalRunTime(const uint64_t x)
{
	this->pimpl->totalRunTime += x;
}

uint64_t Experiment::getTotalRunTime() const
{
	return this->pimpl->totalRunTime;
}

void Experiment::setIsBaselineCase(bool x)
{
	this->pimpl->isBaselineCase = x;
}

bool Experiment::getIsBaselineCase() const
{
	return this->pimpl->isBaselineCase;
}

void Experiment::setFactory(std::shared_ptr<Factory> x)
{
	this->pimpl->factory = x;
}

std::shared_ptr<Factory> Experiment::getFactory() const
{
	return this->pimpl->factory;
}

void Experiment::addProblemSpace(int64_t x, double scale, uint64_t iterations)
{
	auto r = std::make_shared<celero::ExperimentResult>(this);
	r->setProblemSpaceValue(x, scale, iterations);
	this->pimpl->results.push_back(r);
}

size_t Experiment::getResultSize()
{
	if(this->pimpl->results.empty() == true)
	{
		auto defaultResult = std::make_shared<celero::ExperimentResult>(this);
		defaultResult->setProblemSpaceValue(static_cast<int64_t>(TestFixture::Constants::NoProblemSpaceValue), 1.0, this->getIterations());
		this->pimpl->results.push_back(defaultResult);
	}

	return this->pimpl->results.size();
}

std::shared_ptr<celero::ExperimentResult> Experiment::getResult(size_t x)
{
	// get the result OR thrown an exception if the result list is empty;
	return this->pimpl->results.at(x);
}

std::shared_ptr<celero::ExperimentResult> Experiment::getResultByValue(int64_t x)
{
	std::shared_ptr<celero::ExperimentResult> r;

	const auto found = std::find_if(std::begin(this->pimpl->results), std::end(this->pimpl->results),
									[x](std::shared_ptr<celero::ExperimentResult> i) -> bool { return (i->getProblemSpaceValue() == x); });

	if(found != std::end(this->pimpl->results))
	{
		r = (*found);
	}

	return r;
}