/***

  Olive - Non-Linear Video Editor
  Copyright (C) 2022 Olive Team
  Modifications Copyright (C) 2025 mikesolar

  This program is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program.  If not, see <http://www.gnu.org/licenses/>.

***/

#include "renderer.h"

#include "common/filefunctions.h"
#include "node/node.h"
#include "render/colorprocessor.h"
#include "render/job/colortransformjob.h"
#include "render/job/shaderjob.h"

namespace olive
{

bool Renderer::GetColorContext(const ColorTransformJob &color_job,
							   Renderer::ColorContext *ctx)
{
	QMutexLocker locker(&color_cache_mutex_);

	ColorContext &color_ctx = *ctx;

	QString proc_id = color_job.id();

	if (color_cache_.contains(proc_id)) {
		color_ctx = color_cache_.value(proc_id);
		return true;
	} else {
		locker.unlock();

		// Create shader description
		QString ocio_func_name;
		if (color_job.GetFunctionName().isEmpty()) {
			ocio_func_name = "OCIODisplay";
		} else {
			ocio_func_name = color_job.GetFunctionName();
		}
		auto shader_desc = OCIO::GpuShaderDesc::CreateShaderDesc();
		shader_desc->setLanguage(OCIO::GPU_LANGUAGE_GLSL_ES_3_0);
		shader_desc->setFunctionName(ocio_func_name.toUtf8());
		shader_desc->setResourcePrefix("ocio_");

		// Generate shader
		color_job.GetColorProcessor()
			->GetProcessor()
			->getDefaultGPUProcessor()
			->extractGpuShaderInfo(shader_desc);

		ShaderCode code;
		if (const Node *shader_src = color_job.CustomShaderSource()) {
			// Use shader code from associated node
			code = shader_src->GetShaderCode(
				{ color_job.CustomShaderID(), shader_desc->getShaderText() });
		} else {
			// Generate shader code using OCIO stub and our auto-generated name
			code = FileFunctions::ReadFileAsString(
				QStringLiteral(":/shaders/colormanage.frag"));
			code.set_frag_code(
				code.frag_code().arg(shader_desc->getShaderText()));
		}

		// Try to compile shader
		color_ctx.compiled_shader = CreateNativeShader(code);

		if (color_ctx.compiled_shader.isNull()) {
			return false;
		}

		color_ctx.lut3d_textures.resize(shader_desc->getNum3DTextures());
		for (unsigned int i = 0; i < shader_desc->getNum3DTextures(); i++) {
			const char *tex_name = nullptr;
			const char *sampler_name = nullptr;
			unsigned int edge_len = 0;
			OCIO::Interpolation interpolation = OCIO::INTERP_LINEAR;

			shader_desc->get3DTexture(i, tex_name, sampler_name, edge_len,
									  interpolation);

			if (!tex_name || !*tex_name || !sampler_name || !*sampler_name ||
				!edge_len) {
				qCritical() << "3D LUT texture data is corrupted";
				return false;
			}

			const float *values = nullptr;
			shader_desc->get3DTextureValues(i, values);
			if (!values) {
				qCritical() << "3D LUT texture values are missing";
				return false;
			}

			// Allocate 3D LUT
			color_ctx.lut3d_textures[i].texture = CreateTexture(
				VideoParams(edge_len, edge_len, edge_len, PixelFormat::F32,
							VideoParams::kRGBChannelCount),
				values);
			color_ctx.lut3d_textures[i].name = sampler_name;
			color_ctx.lut3d_textures[i].interpolation =
				(interpolation == OCIO::INTERP_NEAREST) ? Texture::kNearest :
													  Texture::kLinear;
		}

		color_ctx.lut1d_textures.resize(shader_desc->getNumTextures());
		for (unsigned int i = 0; i < shader_desc->getNumTextures(); i++) {
			const char *tex_name = nullptr;
			const char *sampler_name = nullptr;
			unsigned int width = 0, height = 0;
			OCIO::GpuShaderDesc::TextureType channel =
				OCIO::GpuShaderDesc::TEXTURE_RGB_CHANNEL;
			OCIO::Interpolation interpolation = OCIO::INTERP_LINEAR;
#if OCIO_VERSION_MAJOR > 2 || (OCIO_VERSION_MAJOR == 2 && OCIO_VERSION_MINOR >= 3)
			OCIO::GpuShaderDesc::TextureDimensions dimensions =
				OCIO::GpuShaderDesc::TEXTURE_2D;
			shader_desc->getTexture(i, tex_name, sampler_name, width, height,
									channel, dimensions, interpolation);
#else
			shader_desc->getTexture(i, tex_name, sampler_name, width, height,
									channel, interpolation);
#endif

			if (!tex_name || !*tex_name || !sampler_name || !*sampler_name ||
				!width) {
				qCritical() << "1D LUT texture data is corrupted";
				return false;
			}

			const float *values = nullptr;
			shader_desc->getTextureValues(i, values);
			if (!values) {
				qCritical() << "1D LUT texture values are missing";
				return false;
			}

			// Allocate 1D LUT
			int lut_channels = (channel ==
								OCIO::GpuShaderDesc::TEXTURE_RED_CHANNEL) ?
								   1 :
								   VideoParams::kRGBChannelCount;
			VideoParams lut_params(width, height, PixelFormat::F32, lut_channels);
			color_ctx.lut1d_textures[i].texture = CreateTexture(lut_params, values);
			color_ctx.lut1d_textures[i].name = sampler_name;
			color_ctx.lut1d_textures[i].interpolation =
				(interpolation == OCIO::INTERP_NEAREST) ? Texture::kNearest :
													  Texture::kLinear;
		}

		locker.relock();
		color_cache_.insert(proc_id, color_ctx);

		return true;
	}
}

void Renderer::BlitColorManaged(const ColorTransformJob &color_job,
								Texture *destination, const VideoParams &params)
{
	ColorContext color_ctx;
	if (!GetColorContext(color_job, &color_ctx)) {
		ShaderJob fallback_job;
		fallback_job.Insert(QStringLiteral("ove_maintex"),
							color_job.GetInputTexture());
		fallback_job.Insert(
			QStringLiteral("ove_mvpmat"),
			NodeValue(NodeValue::kMatrix, color_job.GetTransformMatrix()));

		if (destination) {
			BlitToTexture(GetDefaultShader(), fallback_job, destination,
						  color_job.IsClearDestinationEnabled());
		} else {
			Blit(GetDefaultShader(), fallback_job, params,
				 color_job.IsClearDestinationEnabled());
		}
		return;
	}

	ShaderJob job;
	job.Insert(QStringLiteral("ove_maintex"), color_job.GetInputTexture());
	job.Insert(QStringLiteral("ove_mvpmat"),
			   NodeValue(NodeValue::kMatrix, color_job.GetTransformMatrix()));
	job.Insert(QStringLiteral("ove_cropmatrix"),
			   NodeValue(NodeValue::kMatrix,
						 color_job.GetCropMatrix().inverted()));
	job.Insert(QStringLiteral("ove_maintex_alpha"),
			   NodeValue(NodeValue::kInt,
						 int(color_job.GetInputAlphaAssociation())));
	job.Insert(QStringLiteral("ove_force_opaque"),
			   NodeValue(NodeValue::kBoolean, color_job.GetForceOpaque()));
	job.Insert(color_job.GetValues());

	foreach (const ColorContext::LUT &l, color_ctx.lut3d_textures) {
		job.Insert(l.name, NodeValue(NodeValue::kTexture,
								   QVariant::fromValue(l.texture)));
		job.SetInterpolation(l.name, l.interpolation);
	}
	foreach (const ColorContext::LUT &l, color_ctx.lut1d_textures) {
		job.Insert(l.name, NodeValue(NodeValue::kTexture,
								   QVariant::fromValue(l.texture)));
		job.SetInterpolation(l.name, l.interpolation);
	}

	if (destination) {
		BlitToTexture(color_ctx.compiled_shader, job, destination,
					  color_job.IsClearDestinationEnabled());
	} else {
		Blit(color_ctx.compiled_shader, job, params,
			 color_job.IsClearDestinationEnabled());
	}
}

}
