/*
 * Copyright (c) 2002-2008 LWJGL Project
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * * Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * * Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 *
 * * Neither the name of 'LWJGL' nor the names of
 *   its contributors may be used to endorse or promote products derived
 *   from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.lwjgl.util.generator.opengl;

import org.lwjgl.util.generator.Utils;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.PrintWriter;
import java.nio.file.Path;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.Callable;
import javax.annotation.processing.*;
import javax.lang.model.SourceVersion;
import javax.lang.model.element.TypeElement;
import javax.lang.model.util.ElementFilter;

import static org.lwjgl.util.generator.GeneratorVisitor.saveGeneratedJavaSource;
import static org.lwjgl.util.generator.Utils.getRequiredOption;
import static org.lwjgl.util.generator.Utils.spawn;

/**
 * Generator tool for creating the ContextCapabilities class
 *
 * @author elias_naur <elias_naur@users.sourceforge.net>
 * @version $Revision: 3316 $ $Id: ContextGeneratorProcessorFactory.java 3316
 *          2010-04-09 23:57:40Z spasi $
 */
@SupportedAnnotationTypes({ "*" })
@SupportedSourceVersion(SourceVersion.RELEASE_10)
@SupportedOptions({ "genJavaPath", "generatechecks", "contextspecific" })
public final class GLGeneratorProcessor extends AbstractProcessor {

	private static boolean first_round = true;

	@Override
	public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
		if (roundEnv.processingOver() || !first_round) {
			System.exit(0);
			return true;
		}

		Map<String, String> options = processingEnv.getOptions();
		Path genJavaPath = Path.of(getRequiredOption(options, "genJavaPath", "a path."));

		boolean generate_error_checks = options.containsKey("generatechecks");
		boolean context_specific = options.containsKey("contextspecific");
		try {
			generateContextCapabilitiesSource(genJavaPath, ElementFilter.typesIn(roundEnv.getRootElements()), context_specific, generate_error_checks);
			first_round = false;
			return true;
		} catch (IOException e) {
			throw new RuntimeException(e);
		}
	}

	private void generateContextCapabilitiesSource(Path genJavaPath, Set<TypeElement> templates, boolean context_specific, boolean generate_error_checks) throws IOException {
		long startTime = System.currentTimeMillis();
		ProcessingEnvironment env = this.processingEnv;

		ByteArrayOutputStream writer1 = new ByteArrayOutputStream();
		PrintWriter writer = new PrintWriter(writer1);

		writer.append("/* MACHINE GENERATED FILE, DO NOT EDIT */\n\n"
				+ "package org.lwjgl.opengl;\n\n"
				+ "import org.lwjgl.LWJGLException;\n"
				+ "import org.lwjgl.LWJGLUtil;\n"
				+ "import java.util.Set;\n"
				+ "import java.util.HashSet;\n\n");
		GLCapabilitiesGenerator.generateClassPrologue(writer, context_specific, generate_error_checks);
		for ( TypeElement interface_decl : templates ) {
			if ( interface_decl.getKind().isInterface() ) {
				if ( Utils.isFinal(interface_decl) ) {
					GLCapabilitiesGenerator.generateField(writer, interface_decl);
				}
			}
		}
		writer.append('\n');
		for ( TypeElement interface_decl : templates ) {
			if ( interface_decl.getKind().isInterface() ) {
				GLCapabilitiesGenerator.generateSymbolAddresses(processingEnv, writer, interface_decl);
			}
		}
		writer.append('\n');
		if ( context_specific ) {
			for ( TypeElement interface_decl : templates ) {
				if ( interface_decl.getKind().isInterface() ) {
					GLCapabilitiesGenerator.generateAddressesInitializers(processingEnv, writer, interface_decl);
				}
			}
			writer.append('\n');
		}

		writer.append("\tprivate static void remove(Set supported_extensions, String extension) {\n"
				+ "\t\tLWJGLUtil.logger().log(() -> extension + \" was reported as available but an entry point is missing\");\n"
				+ "\t\tsupported_extensions.remove(extension);\n"
				+ "\t}\n\n");

		GLCapabilitiesGenerator.generateInitStubsPrologue(writer, context_specific);
		for ( TypeElement interface_decl : templates ) {
			if ( interface_decl.getKind().isInterface() ) {
				GLCapabilitiesGenerator.generateSuperClassAdds(writer, interface_decl, processingEnv);
			}
		}
		for ( TypeElement interface_decl : templates ) {
			if ( interface_decl.getKind().isInterface() ) {
				String simple_name = interface_decl.getSimpleName().toString();
				if ( "GL11".equals(simple_name) ) {
					continue;
				}
				GLCapabilitiesGenerator.generateInitStubs(processingEnv, writer, interface_decl, context_specific);
			}
		}
		GLCapabilitiesGenerator.generateInitStubsEpilogue(writer, context_specific);
		writer.append("\n\tstatic void unloadAllStubs() {\n");
		if ( !context_specific ) {
			writer.append("\t\tif (!loaded_stubs)\n"
					+ "\t\t\treturn;\n");
			for ( TypeElement interface_decl : templates ) {
				if ( interface_decl.getKind().isInterface() ) {
					GLCapabilitiesGenerator.generateUnloadStubs(processingEnv, writer, interface_decl);
				}
			}
			writer.append("\t\tloaded_stubs = false;\n");
		}
		writer.append("\t}\n\n");
		GLCapabilitiesGenerator.generateInitializerPrologue(writer);
		for ( TypeElement interface_decl : templates ) {
			if ( interface_decl.getKind().isInterface() ) {
				if ( Utils.isFinal(interface_decl) ) {
					GLCapabilitiesGenerator.generateInitializer(writer, interface_decl, processingEnv);
				}
			}
		}
		writer.append("\t\ttracker.init();\n"
				+ "\t}\n"
				+ "}\n");

		saveGeneratedJavaSource(env.getMessager(), genJavaPath, "org.lwjgl.opengl." + Utils.CONTEXT_CAPS_CLASS_NAME, spawn((Callable<byte[]>) () -> {
			writer.flush();
			return writer1.toByteArray();
		}), startTime);
	}
}