/*******************************************************************************
 * Copyright (c) 2000, 2016 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *     Stephan Herrmann - Contribution for
 *								Bug 458396 - NPE in CodeStream.invoke()
 *******************************************************************************/
package org.eclipse.jdt.internal.compiler.problem;

import org.eclipse.jdt.core.compiler.CategorizedProblem;
import org.eclipse.jdt.core.compiler.CharOperation;
import org.eclipse.jdt.core.compiler.IProblem;
import org.eclipse.jdt.internal.compiler.CompilationResult;
import org.eclipse.jdt.internal.compiler.IErrorHandlingPolicy;
import org.eclipse.jdt.internal.compiler.IProblemFactory;
import org.eclipse.jdt.internal.compiler.ast.CompilationUnitDeclaration;
import org.eclipse.jdt.internal.compiler.env.ICompilationUnit;
import org.eclipse.jdt.internal.compiler.impl.CompilerOptions;
import org.eclipse.jdt.internal.compiler.impl.ReferenceContext;
import org.eclipse.jdt.internal.compiler.util.Util;

/*
 * Compiler error handler, responsible to determine whether
 * a problem is actually a warning or an error; also will
 * decide whether the compilation task can be processed further or not.
 *
 * Behavior : will request its current policy if need to stop on
 *	first error, and if should proceed (persist) with problems.
 */

public class ProblemHandler {

	public final static String[] NoArgument = CharOperation.NO_STRINGS;

	public IErrorHandlingPolicy policy;
	public final IProblemFactory problemFactory;
	public final CompilerOptions options;

	/* When temporarily switching policies, store here the original root policy (for temporary resume). */
	private IErrorHandlingPolicy rootPolicy;

	protected boolean suppressTagging = false;
/*
 * Problem handler can be supplied with a policy to specify
 * its behavior in error handling. Also see static methods for
 * built-in policies.
 *
 */
public ProblemHandler(IErrorHandlingPolicy policy, CompilerOptions options, IProblemFactory problemFactory) {
	this.policy = policy;
	this.problemFactory = problemFactory;
	this.options = options;
}
/*
 * Given the current configuration, answers which category the problem
 * falls into:
 *		Error | Warning | Ignore
 */
public int computeSeverity(int problemId){

	return ProblemSeverities.Error; // by default all problems are errors
}
public CategorizedProblem createProblem(
	char[] fileName,
	int problemId,
	String[] problemArguments,
	String[] messageArguments,
	int severity,
	int problemStartPosition,
	int problemEndPosition,
	int lineNumber,
	int columnNumber) {

	return this.problemFactory.createProblem(
		fileName,
		problemId,
		problemArguments,
		messageArguments,
		severity,
		problemStartPosition,
		problemEndPosition,
		lineNumber,
		columnNumber);
}
public CategorizedProblem createProblem(
		char[] fileName,
		int problemId,
		String[] problemArguments,
		int elaborationId,
		String[] messageArguments,
		int severity,
		int problemStartPosition,
		int problemEndPosition,
		int lineNumber,
		int columnNumber) {
	return this.problemFactory.createProblem(
		fileName,
		problemId,
		problemArguments,
		elaborationId,
		messageArguments,
		severity,
		problemStartPosition,
		problemEndPosition,
		lineNumber,
		columnNumber);
}
public void handle(
	int problemId,
	String[] problemArguments,
	int elaborationId,
	String[] messageArguments,
	int severity,
	int problemStartPosition,
	int problemEndPosition,
	ReferenceContext referenceContext,
	CompilationResult unitResult) {

	if (severity == ProblemSeverities.Ignore)
		return;

	 boolean mandatory = (severity & (ProblemSeverities.Error | ProblemSeverities.Optional)) == ProblemSeverities.Error;
	 if ((severity & ProblemSeverities.InternalError) == 0 && this.policy.ignoreAllErrors()) {
		 // Error is not to be exposed, but clients may need still notification as to whether there are silently-ignored-errors.
		 // if no reference context, we need to abort from the current compilation process
		 if (referenceContext == null) {
			 if ((severity & ProblemSeverities.Error) != 0) { // non reportable error is fatal
				 CategorizedProblem problem = this.createProblem(null, problemId, problemArguments, elaborationId, messageArguments, severity, 0, 0, 0, 0);
				 throw new AbortCompilation(null, problem);
			 } else {
				 return; // ignore non reportable warning
			 }
		 }
		 if (mandatory)
			 referenceContext.tagAsHavingIgnoredMandatoryErrors(problemId);
		 return;
	 }

	if ((severity & ProblemSeverities.Optional) != 0 && problemId != IProblem.Task  && !this.options.ignoreSourceFolderWarningOption) {
		ICompilationUnit cu = unitResult.getCompilationUnit();
		try{
			if (cu != null && cu.ignoreOptionalProblems())
				return;
		// workaround for illegal implementation of ICompilationUnit, see https://bugs.eclipse.org/372351
		} catch (AbstractMethodError ex) {
			// continue
		}
	}

	// if no reference context, we need to abort from the current compilation process
	if (referenceContext == null) {
		if ((severity & ProblemSeverities.Error) != 0) { // non reportable error is fatal
			CategorizedProblem problem = this.createProblem(null, problemId, problemArguments, elaborationId, messageArguments, severity, 0, 0, 0, 0);
			throw new AbortCompilation(null, problem);
		} else {
			return; // ignore non reportable warning
		}
	}

	int[] lineEnds;
	int lineNumber = problemStartPosition >= 0
			? Util.getLineNumber(problemStartPosition, lineEnds = unitResult.getLineSeparatorPositions(), 0, lineEnds.length-1)
			: 0;
	int columnNumber = problemStartPosition >= 0
			? Util.searchColumnNumber(unitResult.getLineSeparatorPositions(), lineNumber, problemStartPosition)
			: 0;
	CategorizedProblem problem =
		this.createProblem(
			unitResult.getFileName(),
			problemId,
			problemArguments,
			elaborationId,
			messageArguments,
			severity,
			problemStartPosition,
			problemEndPosition,
			lineNumber,
			columnNumber);

	if (problem == null) return; // problem couldn't be created, ignore

	switch (severity & ProblemSeverities.Error) {
		case ProblemSeverities.Error :
			record(problem, unitResult, referenceContext, mandatory);
			if ((severity & ProblemSeverities.Fatal) != 0) {
				// don't abort or tag as error if the error is suppressed
				if (!referenceContext.hasErrors() && !mandatory && this.options.suppressOptionalErrors) {
					CompilationUnitDeclaration unitDecl = referenceContext.getCompilationUnitDeclaration();
					if (unitDecl != null && unitDecl.isSuppressed(problem)) {
						return;
					}
				}
				if (!this.suppressTagging || this.options.treatOptionalErrorAsFatal) {
					referenceContext.tagAsHavingErrors();
				}
				// should abort ?
				int abortLevel;
				if ((abortLevel = this.policy.stopOnFirstError() ? ProblemSeverities.AbortCompilation : severity & ProblemSeverities.Abort) != 0) {
					referenceContext.abort(abortLevel, problem);
				}
			}
			break;
		case ProblemSeverities.Warning :
			record(problem, unitResult, referenceContext, false);
			break;
	}
}
/**
 * Standard problem handling API, the actual severity (warning/error/ignore) is deducted
 * from the problem ID and the current compiler options.
 */
public void handle(
	int problemId,
	String[] problemArguments,
	String[] messageArguments,
	int problemStartPosition,
	int problemEndPosition,
	ReferenceContext referenceContext,
	CompilationResult unitResult) {

	this.handle(
		problemId,
		problemArguments,
		0, // no message elaboration
		messageArguments,
		computeSeverity(problemId), // severity inferred using the ID
		problemStartPosition,
		problemEndPosition,
		referenceContext,
		unitResult);
}
public void record(CategorizedProblem problem, CompilationResult unitResult, ReferenceContext referenceContext, boolean mandatoryError) {
	unitResult.record(problem, referenceContext, mandatoryError);
}
/** @return old policy. */
public IErrorHandlingPolicy switchErrorHandlingPolicy(IErrorHandlingPolicy newPolicy) {
	if (this.rootPolicy == null)
		this.rootPolicy = this.policy;
	IErrorHandlingPolicy presentPolicy = this.policy;
	this.policy = newPolicy;
	return presentPolicy;
}
/**
 * Temporarily suspend a temporary error handling policy.
 * @return old policy.
 */
public IErrorHandlingPolicy suspendTempErrorHandlingPolicy() {
	IErrorHandlingPolicy presentPolicy = this.policy;
	if (this.rootPolicy != null)
		this.policy = this.rootPolicy;
	return presentPolicy;
}
/**
 * Resume from a corresponding {@link #suspendTempErrorHandlingPolicy()}.
 * @param previousPolicy the result value of the matching suspend call
 */
public void resumeTempErrorHandlingPolicy(IErrorHandlingPolicy previousPolicy) {
	this.policy = previousPolicy;
}
}