/*-------------------------------------------------------------------------
 * drawElements Quality Program OpenGL (ES) Module
 * -----------------------------------------------
 *
 * Copyright 2014 The Android Open Source Project
 *
 * 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.
 *
 *//*!
 * \file
 * \brief Shader performance measurer; handles calibration and measurement
 *//*--------------------------------------------------------------------*/

#include "glsShaderPerformanceMeasurer.hpp"
#include "gluDefs.hpp"
#include "tcuTestLog.hpp"
#include "tcuRenderTarget.hpp"
#include "deStringUtil.hpp"
#include "deMath.h"
#include "deClock.h"

#include "glwFunctions.hpp"
#include "glwEnums.hpp"

#include <algorithm>

using tcu::Vec4;
using std::string;
using std::vector;
using tcu::TestLog;
using namespace glw; // GL types

namespace deqp
{
namespace gls
{

static inline float triangleInterpolate (float v0, float v1, float v2, float x, float y)
{
	return v0 + (v2-v0)*x + (v1-v0)*y;
}

static inline float triQuadInterpolate (float x, float y, const tcu::Vec4& quad)
{
	// \note Top left fill rule.
	if (x + y < 1.0f)
		return triangleInterpolate(quad.x(), quad.y(), quad.z(), x, y);
	else
		return triangleInterpolate(quad.w(), quad.z(), quad.y(), 1.0f-x, 1.0f-y);
}

static inline int getNumVertices (int gridSizeX, int gridSizeY)
{
	return (gridSizeX + 1) * (gridSizeY + 1);
}

static inline int getNumIndices (int gridSizeX, int gridSizeY)
{
	return gridSizeX*gridSizeY*6;
}

static inline deUint16 getVtxIndex (int x, int y, int gridSizeX)
{
	return (deUint16)(y*(gridSizeX+1) + x);
}

static void generateVertices (std::vector<float>& dst, int gridSizeX, int gridSizeY, const AttribSpec& spec)
{
	const int numComponents = 4;

	DE_ASSERT((gridSizeX + 1)*(gridSizeY + 1) <= (1<<16)); // Must fit into 16-bit indices.
	DE_ASSERT(gridSizeX >= 1 && gridSizeY >= 1);
	dst.resize((gridSizeX + 1) * (gridSizeY + 1) * 4);

	for (int y = 0; y <= gridSizeY; y++)
	{
		for (int x = 0; x <= gridSizeX; x++)
		{
			float	xf	= (float)x / (float)gridSizeX;
			float	yf	= (float)y / (float)gridSizeY;

			for (int compNdx = 0; compNdx < numComponents; compNdx++)
				dst[getVtxIndex(x, y, gridSizeX)*numComponents + compNdx] = triQuadInterpolate(xf, yf, tcu::Vec4(spec.p00[compNdx], spec.p01[compNdx], spec.p10[compNdx], spec.p11[compNdx]));
		}
	}
}

static void generateIndices (std::vector<deUint16>& dst, int gridSizeX, int gridSizeY)
{
	const int	numIndicesPerQuad	= 6;
	int			numIndices			= gridSizeX * gridSizeY * numIndicesPerQuad;
	dst.resize(numIndices);

	for (int y = 0; y < gridSizeY; y++)
	{
		for (int x = 0; x < gridSizeX; x++)
		{
			int quadNdx = y*gridSizeX + x;

			dst[quadNdx*numIndicesPerQuad + 0] = getVtxIndex(x+0, y+0, gridSizeX);
			dst[quadNdx*numIndicesPerQuad + 1] = getVtxIndex(x+1, y+0, gridSizeX);
			dst[quadNdx*numIndicesPerQuad + 2] = getVtxIndex(x+0, y+1, gridSizeX);

			dst[quadNdx*numIndicesPerQuad + 3] = getVtxIndex(x+0, y+1, gridSizeX);
			dst[quadNdx*numIndicesPerQuad + 4] = getVtxIndex(x+1, y+0, gridSizeX);
			dst[quadNdx*numIndicesPerQuad + 5] = getVtxIndex(x+1, y+1, gridSizeX);
		}
	}
}

ShaderPerformanceMeasurer::ShaderPerformanceMeasurer (const glu::RenderContext& renderCtx, PerfCaseType measureType)
	: m_renderCtx			(renderCtx)
	, m_gridSizeX			(measureType == CASETYPE_FRAGMENT	? 1		: 255)
	, m_gridSizeY			(measureType == CASETYPE_FRAGMENT	? 1		: 255)
	, m_viewportWidth		(measureType == CASETYPE_VERTEX		? 32	: renderCtx.getRenderTarget().getWidth())
	, m_viewportHeight		(measureType == CASETYPE_VERTEX		? 32	: renderCtx.getRenderTarget().getHeight())
	, m_state(STATE_UNINITIALIZED)
	, m_isFirstIteration	(false)
	, m_prevRenderStartTime	(0)
	, m_result				(-1.0f, -1.0f)
	, m_indexBuffer			(0)
	, m_vao					(0)
{
}

void ShaderPerformanceMeasurer::logParameters (TestLog& log) const
{
	log << TestLog::Message << "Grid size: " << m_gridSizeX << "x" << m_gridSizeY << TestLog::EndMessage
		<< TestLog::Message << "Viewport: " << m_viewportWidth << "x" << m_viewportHeight << TestLog::EndMessage;
}

void ShaderPerformanceMeasurer::init (deUint32 program, const vector<AttribSpec>& attributes, int calibratorInitialNumCalls)
{
	DE_ASSERT(m_state == STATE_UNINITIALIZED);

	const glw::Functions&	gl		= m_renderCtx.getFunctions();
	const bool				useVAO	= glu::isContextTypeGLCore(m_renderCtx.getType());

	if (useVAO)
	{
		DE_ASSERT(!m_vao);
		gl.genVertexArrays(1, &m_vao);
		gl.bindVertexArray(m_vao);
		GLU_EXPECT_NO_ERROR(gl.getError(), "Create VAO");
	}

	// Validate that we have sane grid and viewport setup.

	DE_ASSERT(de::inBounds(m_gridSizeX, 1, 256) && de::inBounds(m_gridSizeY, 1, 256));

	{
		bool widthTooSmall		= m_renderCtx.getRenderTarget().getWidth() < m_viewportWidth;
		bool heightTooSmall		= m_renderCtx.getRenderTarget().getHeight() < m_viewportHeight;

		if (widthTooSmall || heightTooSmall)
			throw tcu::NotSupportedError("Render target too small (" +
											 (widthTooSmall  ?									   "width must be at least "  + de::toString(m_viewportWidth)  : "") +
											 (heightTooSmall ? string(widthTooSmall ? ", " : "") + "height must be at least " + de::toString(m_viewportHeight) : "") +
											 ")");
	}

	TCU_CHECK_INTERNAL(de::inRange(m_viewportWidth,		1, m_renderCtx.getRenderTarget().getWidth()) &&
					   de::inRange(m_viewportHeight,	1, m_renderCtx.getRenderTarget().getHeight()));

	// Insert a_position to attributes.
	m_attributes = attributes;
	m_attributes.push_back(AttribSpec("a_position",
									  Vec4(-1.0f, -1.0f, 0.0f, 1.0f),
									  Vec4( 1.0f, -1.0f, 0.0f, 1.0f),
									  Vec4(-1.0f,  1.0f, 0.0f, 1.0f),
									  Vec4( 1.0f,  1.0f, 0.0f, 1.0f)));

	// Generate indices.
	{
		std::vector<deUint16> indices;
		generateIndices(indices, m_gridSizeX, m_gridSizeY);

		gl.genBuffers(1, &m_indexBuffer);
		gl.bindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_indexBuffer);
		gl.bufferData(GL_ELEMENT_ARRAY_BUFFER, (GLsizeiptr)(indices.size()*sizeof(deUint16)), &indices[0], GL_STATIC_DRAW);

		GLU_EXPECT_NO_ERROR(gl.getError(), "Upload index data");
	}

	// Generate vertices.
	m_attribBuffers.resize(m_attributes.size(), 0);
	gl.genBuffers((GLsizei)m_attribBuffers.size(), &m_attribBuffers[0]);

	for (int attribNdx = 0; attribNdx < (int)m_attributes.size(); attribNdx++)
	{
		std::vector<float> vertices;
		generateVertices(vertices, m_gridSizeX, m_gridSizeY, m_attributes[attribNdx]);

		gl.bindBuffer(GL_ARRAY_BUFFER, m_attribBuffers[attribNdx]);
		gl.bufferData(GL_ARRAY_BUFFER, (GLsizeiptr)(vertices.size()*sizeof(float)), &vertices[0], GL_STATIC_DRAW);
	}

	GLU_EXPECT_NO_ERROR(gl.getError(), "Upload vertex data");

	// Setup attribute bindings.
	for (int attribNdx = 0; attribNdx < (int)m_attributes.size(); attribNdx++)
	{
		int location = gl.getAttribLocation(program, m_attributes[attribNdx].name.c_str());

		if (location >= 0)
		{
			gl.enableVertexAttribArray(location);
			gl.bindBuffer(GL_ARRAY_BUFFER, m_attribBuffers[attribNdx]);
			gl.vertexAttribPointer(location, 4, GL_FLOAT, GL_FALSE, 0, DE_NULL);
		}

		GLU_EXPECT_NO_ERROR(gl.getError(), "Setup vertex attribute state");
	}

	gl.useProgram(program);
	GLU_EXPECT_NO_ERROR(gl.getError(), "glUseProgram()");

	m_state = STATE_MEASURING;
	m_isFirstIteration = true;

	m_calibrator.clear(CalibratorParameters(calibratorInitialNumCalls, 10 /* calibrate iteration frames */, 2000.0f /* calibrate iteration shortcut threshold (ms) */, 16 /* max calibrate iterations */,
											1000.0f/30.0f /* frame time (ms) */, 1000.0f/60.0f /* frame time cap (ms) */, 1000.0f /* target measure duration (ms) */));
}

void ShaderPerformanceMeasurer::deinit (void)
{
	const glw::Functions& gl = m_renderCtx.getFunctions();

	if (m_indexBuffer)
	{
		gl.deleteBuffers(1, &m_indexBuffer);
		m_indexBuffer = 0;
	}

	if (m_vao)
	{
		gl.deleteVertexArrays(1, &m_vao);
		m_vao = 0;
	}

	if (!m_attribBuffers.empty())
	{
		gl.deleteBuffers((GLsizei)m_attribBuffers.size(), &m_attribBuffers[0]);
		m_attribBuffers.clear();
	}

	m_state = STATE_UNINITIALIZED;
}

void ShaderPerformanceMeasurer::render (int numDrawCalls)
{
	const glw::Functions&	gl			= m_renderCtx.getFunctions();
	GLsizei					numIndices	= (GLsizei)getNumIndices(m_gridSizeX, m_gridSizeY);

	gl.viewport(0, 0, m_viewportWidth, m_viewportHeight);

	for (int callNdx = 0; callNdx < numDrawCalls; callNdx++)
		gl.drawElements(GL_TRIANGLES, numIndices, GL_UNSIGNED_SHORT, DE_NULL);
}

void ShaderPerformanceMeasurer::iterate (void)
{
	DE_ASSERT(m_state == STATE_MEASURING);

	deUint64 renderStartTime = deGetMicroseconds();
	render(m_calibrator.getCallCount()); // Always render. This gives more stable performance behavior.

	TheilSenCalibrator::State calibratorState = m_calibrator.getState();

	if (calibratorState == TheilSenCalibrator::STATE_RECOMPUTE_PARAMS)
	{
		m_calibrator.recomputeParameters();

		m_isFirstIteration = true;
		m_prevRenderStartTime = renderStartTime;
	}
	else if (calibratorState == TheilSenCalibrator::STATE_MEASURE)
	{
		if (!m_isFirstIteration)
			m_calibrator.recordIteration(renderStartTime - m_prevRenderStartTime);

		m_isFirstIteration = false;
		m_prevRenderStartTime = renderStartTime;
	}
	else
	{
		DE_ASSERT(calibratorState == TheilSenCalibrator::STATE_FINISHED);

		GLU_EXPECT_NO_ERROR(m_renderCtx.getFunctions().getError(), "End of rendering");

		const MeasureState& measureState = m_calibrator.getMeasureState();

		// Compute result.
		deUint64	totalTime			= measureState.getTotalTime();
		int			numFrames			= (int)measureState.frameTimes.size();
		deInt64		numQuadGrids		= measureState.numDrawCalls * numFrames;
		deInt64		numPixels			= (deInt64)m_viewportWidth * (deInt64)m_viewportHeight * numQuadGrids;
		deInt64		numVertices			= (deInt64)getNumVertices(m_gridSizeX, m_gridSizeY) * numQuadGrids;
		double		mfragPerSecond		= (double)numPixels / (double)totalTime;
		double		mvertPerSecond		= (double)numVertices / (double)totalTime;

		m_result = Result((float)mvertPerSecond, (float)mfragPerSecond);
		m_state = STATE_FINISHED;
	}
}

void ShaderPerformanceMeasurer::logMeasurementInfo (TestLog& log) const
{
	DE_ASSERT(m_state == STATE_FINISHED);

	const MeasureState& measureState(m_calibrator.getMeasureState());

	// Compute totals.
	deUint64	totalTime			= measureState.getTotalTime();
	int			numFrames			= (int)measureState.frameTimes.size();
	deInt64		numQuadGrids		= measureState.numDrawCalls * numFrames;
	deInt64		numPixels			= (deInt64)m_viewportWidth * (deInt64)m_viewportHeight * numQuadGrids;
	deInt64		numVertices			= (deInt64)getNumVertices(m_gridSizeX, m_gridSizeY) * numQuadGrids;
	double		mfragPerSecond		= (double)numPixels / (double)totalTime;
	double		mvertPerSecond		= (double)numVertices / (double)totalTime;
	double		framesPerSecond		= (double)numFrames / ((double)totalTime / 1000000.0);

	logCalibrationInfo(log, m_calibrator);

	log << TestLog::Float("FramesPerSecond",		"Frames per second in measurement",	"Frames/s",				QP_KEY_TAG_PERFORMANCE,	(float)framesPerSecond)
		<< TestLog::Float("FragmentsPerVertices",	"Vertex-fragment ratio",			"Fragments/Vertices",	QP_KEY_TAG_NONE,		(float)numPixels / (float)numVertices)
		<< TestLog::Float("FragmentPerf",			"Fragment performance",				"MPix/s",				QP_KEY_TAG_PERFORMANCE, (float)mfragPerSecond)
		<< TestLog::Float("VertexPerf",				"Vertex performance",				"MVert/s",				QP_KEY_TAG_PERFORMANCE, (float)mvertPerSecond);
}

void ShaderPerformanceMeasurer::setGridSize (int gridW, int gridH)
{
	DE_ASSERT(m_state == STATE_UNINITIALIZED);
	DE_ASSERT(de::inBounds(gridW, 1, 256) && de::inBounds(gridH, 1, 256));
	m_gridSizeX		= gridW;
	m_gridSizeY		= gridH;
}

void ShaderPerformanceMeasurer::setViewportSize (int width, int height)
{
	DE_ASSERT(m_state == STATE_UNINITIALIZED);
	DE_ASSERT(de::inRange(width,	1, m_renderCtx.getRenderTarget().getWidth()) &&
			  de::inRange(height,	1, m_renderCtx.getRenderTarget().getHeight()));
	m_viewportWidth		= width;
	m_viewportHeight	= height;
}

} // gls
} // deqp