/*
 * Copyright (C) 2009-2018 The Project Lombok Authors.
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package lombok.eclipse;

import static lombok.eclipse.Eclipse.*;
import static lombok.eclipse.handlers.EclipseHandlerUtil.*;
import static lombok.eclipse.EcjAugments.ASTNode_handled;

import java.io.IOException;
import java.lang.annotation.Annotation;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.SortedSet;
import java.util.TreeSet;

import lombok.Lombok;
import lombok.core.AnnotationValues;
import lombok.core.AnnotationValues.AnnotationValueDecodeFail;
import lombok.core.configuration.ConfigurationKeysLoader;
import lombok.core.HandlerPriority;
import lombok.core.SpiLoadUtil;
import lombok.core.TypeLibrary;
import lombok.core.TypeResolver;

import org.eclipse.jdt.internal.compiler.ast.ASTNode;
import org.eclipse.jdt.internal.compiler.ast.CompilationUnitDeclaration;
import org.eclipse.jdt.internal.compiler.ast.TypeReference;

This class tracks 'handlers' and knows how to invoke them for any given AST node.
This class can find the handlers (via SPI discovery) and will set up the given AST node, such as
building an AnnotationValues instance.
/**
 * This class tracks 'handlers' and knows how to invoke them for any given AST node.
 * 
 * This class can find the handlers (via SPI discovery) and will set up the given AST node, such as
 * building an AnnotationValues instance.
 */
public class HandlerLibrary {
	
Creates a new HandlerLibrary. Errors will be reported to the Eclipse Error log. You probably want to use load() instead. /**
	 * Creates a new HandlerLibrary. Errors will be reported to the Eclipse Error log.
	 * You probably want to use {@link #load()} instead.
	 */
	public HandlerLibrary() {
		ConfigurationKeysLoader.LoaderLoader.loadAllConfigurationKeys();
	}
	
	private TypeLibrary typeLibrary = new TypeLibrary();
	
	private static class VisitorContainer {
		private final EclipseASTVisitor visitor;
		private final long priority;
		private final boolean deferUntilPostDiet;
		
		VisitorContainer(EclipseASTVisitor visitor) {
			this.visitor = visitor;
			this.deferUntilPostDiet = visitor.getClass().isAnnotationPresent(DeferUntilPostDiet.class);
			HandlerPriority hp = visitor.getClass().getAnnotation(HandlerPriority.class);
			this.priority = hp == null ? 0L : (((long)hp.value()) << 32) + hp.subValue();
		}
		
		public boolean deferUntilPostDiet() {
			return deferUntilPostDiet;
		}
		
		public long getPriority() {
			return priority;
		}
	}
	
	private static class AnnotationHandlerContainer<T extends Annotation> {
		private final EclipseAnnotationHandler<T> handler;
		private final Class<T> annotationClass;
		private final long priority;
		private final boolean deferUntilPostDiet;
		
		AnnotationHandlerContainer(EclipseAnnotationHandler<T> handler, Class<T> annotationClass) {
			this.handler = handler;
			this.annotationClass = annotationClass;
			this.deferUntilPostDiet = handler.getClass().isAnnotationPresent(DeferUntilPostDiet.class);
			HandlerPriority hp = handler.getClass().getAnnotation(HandlerPriority.class);
			this.priority = hp == null ? 0L : (((long)hp.value()) << 32) + hp.subValue();
		}
		
		public void handle(org.eclipse.jdt.internal.compiler.ast.Annotation annotation,
				final EclipseNode annotationNode) {
			AnnotationValues<T> annValues = createAnnotation(annotationClass, annotationNode);
			handler.handle(annValues, annotation, annotationNode);
		}
		
		public void preHandle(org.eclipse.jdt.internal.compiler.ast.Annotation annotation,
				final EclipseNode annotationNode) {
			AnnotationValues<T> annValues = createAnnotation(annotationClass, annotationNode);
			handler.preHandle(annValues, annotation, annotationNode);
		}
		
		public boolean deferUntilPostDiet() {
			return deferUntilPostDiet;
		}
		
		public long getPriority() {
			return priority;
		}
	}
	
	private Map<String, AnnotationHandlerContainer<?>> annotationHandlers =
		new HashMap<String, AnnotationHandlerContainer<?>>();
	
	private Collection<VisitorContainer> visitorHandlers = new ArrayList<VisitorContainer>();

	
Creates a new HandlerLibrary.  Errors will be reported to the Eclipse Error log.
then uses SPI discovery to load all annotation and visitor based handlers so that future calls
to the handle methods will defer to these handlers.
/**
	 * Creates a new HandlerLibrary.  Errors will be reported to the Eclipse Error log.
	 * then uses SPI discovery to load all annotation and visitor based handlers so that future calls
	 * to the handle methods will defer to these handlers.
	 */
	public static HandlerLibrary load() {
		HandlerLibrary lib = new HandlerLibrary();
		
		loadAnnotationHandlers(lib);
		loadVisitorHandlers(lib);
		
		lib.calculatePriorities();
		
		return lib;
	}
	
	private SortedSet<Long> priorities;
	
	public SortedSet<Long> getPriorities() {
		return priorities;
	}
	
	private void calculatePriorities() {
		SortedSet<Long> set = new TreeSet<Long>();
		for (AnnotationHandlerContainer<?> container : annotationHandlers.values()) set.add(container.getPriority());
		for (VisitorContainer container : visitorHandlers) set.add(container.getPriority());
		this.priorities = Collections.unmodifiableSortedSet(set);
	}
	
	
Uses SPI Discovery to find implementations of EclipseAnnotationHandler. /** Uses SPI Discovery to find implementations of {@link EclipseAnnotationHandler}. */
	@SuppressWarnings({"rawtypes", "unchecked"})
	private static void loadAnnotationHandlers(HandlerLibrary lib) {
		try {
			for (EclipseAnnotationHandler<?> handler : SpiLoadUtil.findServices(EclipseAnnotationHandler.class, EclipseAnnotationHandler.class.getClassLoader())) {
				try {
					Class<? extends Annotation> annotationClass = handler.getAnnotationHandledByThisHandler();
					AnnotationHandlerContainer<?> container = new AnnotationHandlerContainer(handler, annotationClass);
					String annotationClassName = container.annotationClass.getName().replace("$", ".");
					if (lib.annotationHandlers.put(annotationClassName, container) != null) {
						error(null, "Duplicate handlers for annotation type: " + annotationClassName, null);
					}
					lib.typeLibrary.addType(container.annotationClass.getName());
				} catch (Throwable t) {
					error(null, "Can't load Lombok annotation handler for Eclipse: ", t);
				}
			}
		} catch (IOException e) {
			throw Lombok.sneakyThrow(e);
		}
	}
	
	
Uses SPI Discovery to find implementations of EclipseASTVisitor. /** Uses SPI Discovery to find implementations of {@link EclipseASTVisitor}. */
	private static void loadVisitorHandlers(HandlerLibrary lib) {
		try {
			for (EclipseASTVisitor visitor : SpiLoadUtil.findServices(EclipseASTVisitor.class, EclipseASTVisitor.class.getClassLoader())) {
				lib.visitorHandlers.add(new VisitorContainer(visitor));
			}
		} catch (Throwable t) {
			throw Lombok.sneakyThrow(t);
		}
	}
	
	private boolean checkAndSetHandled(ASTNode node) {
		return !ASTNode_handled.getAndSet(node, true);
	}
	
	private boolean needsHandling(ASTNode node) {
		return !ASTNode_handled.get(node);
	}
	
	
Handles the provided annotation node by first finding a qualifying instance of EclipseAnnotationHandler and if one exists, calling it with a freshly cooked up instance of AnnotationValues. Note that depending on the printASTOnly flag, the PrintAST annotation will either be silently skipped, or everything that isn't PrintAST will be skipped. The HandlerLibrary will attempt to guess if the given annotation node represents a lombok annotation. For example, if lombok.* is in the import list, then this method will guess that Getter refers to lombok.Getter, presuming that HandleGetter has been loaded. 
Params:
ast – The Compilation Unit that contains the Annotation AST Node.
annotationNode – The Lombok AST Node representing the Annotation AST Node.
annotation – 'node.get()' - convenience parameter.
priority – current prioritiy
Returns:
the priority we want to run - MAX_VALUE means never/**
	 * Handles the provided annotation node by first finding a qualifying instance of
	 * {@link EclipseAnnotationHandler} and if one exists, calling it with a freshly cooked up
	 * instance of {@link AnnotationValues}.
	 * 
	 * Note that depending on the printASTOnly flag, the {@link lombok.core.PrintAST} annotation
	 * will either be silently skipped, or everything that isn't {@code PrintAST} will be skipped.
	 * 
	 * The HandlerLibrary will attempt to guess if the given annotation node represents a lombok annotation.
	 * For example, if {@code lombok.*} is in the import list, then this method will guess that
	 * {@code Getter} refers to {@code lombok.Getter}, presuming that {@link lombok.eclipse.handlers.HandleGetter}
	 * has been loaded.
	 * 
	 * @param ast The Compilation Unit that contains the Annotation AST Node.
	 * @param annotationNode The Lombok AST Node representing the Annotation AST Node.
	 * @param annotation 'node.get()' - convenience parameter.
	 * @param priority current prioritiy
	 * @return the priority we want to run - MAX_VALUE means never
	 */
	public long handleAnnotation(CompilationUnitDeclaration ast, EclipseNode annotationNode, org.eclipse.jdt.internal.compiler.ast.Annotation annotation, long priority) {
		TypeResolver resolver = new TypeResolver(annotationNode.getImportList());
		TypeReference rawType = annotation.type;
		if (rawType == null) return Long.MAX_VALUE;
		
		String fqn = resolver.typeRefToFullyQualifiedName(annotationNode, typeLibrary, toQualifiedName(annotation.type.getTypeName()));
		if (fqn == null) return Long.MAX_VALUE;
		AnnotationHandlerContainer<?> container = annotationHandlers.get(fqn);
		if (container == null) return Long.MAX_VALUE;
		
		if (priority < container.getPriority()) return container.getPriority(); // we want to run at this priority
		if (priority > container.getPriority()) return Long.MAX_VALUE; // it's over- we do not want to run again
		
		if (!annotationNode.isCompleteParse() && container.deferUntilPostDiet()) {
			if (needsHandling(annotation)) container.preHandle(annotation, annotationNode);
			return Long.MAX_VALUE;
		}
		
		try {
			if (checkAndSetHandled(annotation)) container.handle(annotation, annotationNode);
		} catch (AnnotationValueDecodeFail fail) {
			fail.owner.setError(fail.getMessage(), fail.idx);
		} catch (Throwable t) {
			error(ast, String.format("Lombok annotation handler %s failed", container.handler.getClass()), t);
		}
		return Long.MAX_VALUE;
	}
	
	
Will call all registered EclipseASTVisitor instances. /**
	 * Will call all registered {@link EclipseASTVisitor} instances.
	 */
	public long callASTVisitors(EclipseAST ast, long priority, boolean isCompleteParse) {
		long nearestPriority = Long.MAX_VALUE;
		for (VisitorContainer container : visitorHandlers) {
			if (priority < container.getPriority()) nearestPriority = Math.min(container.getPriority(), nearestPriority);
			if (!isCompleteParse && container.deferUntilPostDiet()) continue;
			if (priority != container.getPriority()) continue;
			try {
				ast.traverse(container.visitor);
			} catch (Throwable t) {
				error((CompilationUnitDeclaration) ast.top().get(),
						String.format("Lombok visitor handler %s failed", container.visitor.getClass()), t);
			}
		}
		return nearestPriority;
	}
}