/*

 * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/*

 * @test

 * @bug 7023233

 * @summary False positive for -Xlint:try with nested try with resources blocks

 */

import com.sun.source.util.JavacTask;

import com.sun.tools.javac.api.ClientCodeWrapper;

import com.sun.tools.javac.api.JavacTool;

import com.sun.tools.javac.util.JCDiagnostic;

import java.net.URI;

import java.util.Arrays;

import javax.tools.Diagnostic;

import javax.tools.JavaCompiler;

import javax.tools.JavaFileObject;

import javax.tools.SimpleJavaFileObject;

import javax.tools.StandardJavaFileManager;

import javax.tools.ToolProvider;

public class UnusedResourcesTest {

    enum XlintOption {

        NONE("none"),

        TRY("try");

        String opt;

        XlintOption(String opt) {

            this.opt = opt;

        }

        String getXlintOption() {

            return "-Xlint:" + opt;

        }

    }

    enum TwrStmt {

        TWR1("res1"),

        TWR2("res2"),

        TWR3("res3");

        final String resourceName;

        private TwrStmt(String resourceName) {

            this.resourceName = resourceName;

        }

    }

    enum SuppressLevel {

        NONE,

        SUPPRESS;

        String getSuppressAnno() {

            return this == SUPPRESS ?

                "@SuppressWarnings(\"try\")" :

                "";

        }

    }

    enum ResourceUsage {

        NONE(null),

        USE_R1(TwrStmt.TWR1),

        USE_R2(TwrStmt.TWR2),

        USE_R3(TwrStmt.TWR3);

        TwrStmt stmt;

        private ResourceUsage(TwrStmt stmt) {

            this.stmt = stmt;

        }

        String usedResourceName() {

            return stmt != null ? stmt.resourceName : null;

        }

        boolean isUsedIn(TwrStmt res, TwrStmt stmt) {

            return this.stmt == res &&

                    stmt.ordinal() >= this.stmt.ordinal();

        }

        String getUsage(TwrStmt stmt) {

            return this != NONE && stmt.ordinal() >= this.stmt.ordinal() ?

                "use(" + usedResourceName() + ");" :

                "";

        }

    }

    static class JavaSource extends SimpleJavaFileObject {

        String template = "class Resource implements AutoCloseable {\n" +

                              "public void close() {}\n" +

                          "}\n" +

                          "class Test {\n" +

                              "void use(Resource r) {}\n" +

                              "#S void test() {\n" +

                                 "try (Resource #R1 = new Resource()) {\n" +

                                    "#U1_R1\n" +

                                    "#U1_R2\n" +

                                    "#U1_R3\n" +

                                    "try (Resource #R2 = new Resource()) {\n" +

                                       "#U2_R1\n" +

                                       "#U2_R2\n" +

                                       "#U2_R3\n" +

                                       "try (Resource #R3 = new Resource()) {\n" +

                                           "#U3_R1\n" +

                                           "#U3_R2\n" +

                                           "#U3_R3\n" +

                                       "}\n" +

                                    "}\n" +

                                 "}\n" +

                              "}\n" +

                          "}\n";

        String source;

        public JavaSource(SuppressLevel suppressLevel, ResourceUsage usage1,

                ResourceUsage usage2, ResourceUsage usage3) {

            super(URI.create("myfo:/Test.java"), JavaFileObject.Kind.SOURCE);

            source = template.replace("#S", suppressLevel.getSuppressAnno()).

                    replace("#R1", TwrStmt.TWR1.resourceName).

                    replace("#R2", TwrStmt.TWR2.resourceName).

                    replace("#R3", TwrStmt.TWR3.resourceName).

                    replace("#U1_R1", usage1.getUsage(TwrStmt.TWR1)).

                    replace("#U1_R2", usage2.getUsage(TwrStmt.TWR1)).

                    replace("#U1_R3", usage3.getUsage(TwrStmt.TWR1)).

                    replace("#U2_R1", usage1.getUsage(TwrStmt.TWR2)).

                    replace("#U2_R2", usage2.getUsage(TwrStmt.TWR2)).

                    replace("#U2_R3", usage3.getUsage(TwrStmt.TWR2)).

                    replace("#U3_R1", usage1.getUsage(TwrStmt.TWR3)).

                    replace("#U3_R2", usage2.getUsage(TwrStmt.TWR3)).

                    replace("#U3_R3", usage3.getUsage(TwrStmt.TWR3));

        }

        @Override

        public CharSequence getCharContent(boolean ignoreEncodingErrors) {

            return source;

        }

    }

    public static void main(String... args) throws Exception {

        for (XlintOption xlint : XlintOption.values()) {

            for (SuppressLevel suppressLevel : SuppressLevel.values()) {

                for (ResourceUsage usage1 : ResourceUsage.values()) {

                    for (ResourceUsage usage2 : ResourceUsage.values()) {

                        for (ResourceUsage usage3 : ResourceUsage.values()) {

                                test(xlint,

                                        suppressLevel,

                                        usage1,

                                        usage2,

                                        usage3);

                        }

                    }

                }

            }

        }

    }

    // Create a single file manager and reuse it for each compile to save time.

    static StandardJavaFileManager fm = JavacTool.create().getStandardFileManager(null, null, null);

    static void test(XlintOption xlint, SuppressLevel suppressLevel, ResourceUsage usage1,

                ResourceUsage usage2, ResourceUsage usage3) throws Exception {

        final JavaCompiler tool = ToolProvider.getSystemJavaCompiler();

        JavaSource source = new JavaSource(suppressLevel, usage1, usage2, usage3);

        DiagnosticChecker dc = new DiagnosticChecker();

        JavacTask ct = (JavacTask)tool.getTask(null, fm, dc,

                Arrays.asList(xlint.getXlintOption()), null, Arrays.asList(source));

        ct.analyze();

        check(source, xlint, suppressLevel, usage1, usage2, usage3, dc);

    }

    static void check(JavaSource source, XlintOption xlint, SuppressLevel suppressLevel,

                ResourceUsage usage1, ResourceUsage usage2, ResourceUsage usage3, DiagnosticChecker dc) {

        ResourceUsage[] usages = { usage1, usage2, usage3 };

        boolean[] unusedFound = { dc.unused_r1, dc.unused_r2, dc.unused_r3 };

        boolean[] usedResources = { false, false, false };

        for (TwrStmt res : TwrStmt.values()) {

            outer: for (TwrStmt stmt : TwrStmt.values()) {

                for (ResourceUsage usage : usages) {

                    if (usage.isUsedIn(res, stmt)) {

                        usedResources[res.ordinal()] = true;

                        break outer;

                    }

                }

            }

        }

        for (TwrStmt stmt : TwrStmt.values()) {

            boolean unused = !usedResources[stmt.ordinal()] &&

                    xlint == XlintOption.TRY &&

                    suppressLevel != SuppressLevel.SUPPRESS;

            if (unused != unusedFound[stmt.ordinal()]) {

                throw new Error("invalid diagnostics for source:\n" +

                    source.getCharContent(true) +

                    "\nOptions: " + xlint.getXlintOption() +

                    "\nFound unused res1: " + unusedFound[0] +

                    "\nFound unused res2: " + unusedFound[1] +

                    "\nFound unused res3: " + unusedFound[2] +

                    "\nExpected unused res1: " + !usedResources[0] +

                    "\nExpected unused res2: " + !usedResources[1] +

                    "\nExpected unused res3: " + !usedResources[2]);

            }

        }

    }

    static class DiagnosticChecker implements javax.tools.DiagnosticListener<JavaFileObject> {

        boolean unused_r1 = false;

        boolean unused_r2 = false;

        boolean unused_r3 = false;

        public void report(Diagnostic<? extends JavaFileObject> diagnostic) {

            if (diagnostic.getKind() == Diagnostic.Kind.WARNING &&

                    diagnostic.getCode().contains("try.resource.not.referenced")) {

                String varName = unwrap(diagnostic).getArgs()[0].toString();

                if (varName.equals(TwrStmt.TWR1.resourceName)) {

                    unused_r1 = true;

                } else if (varName.equals(TwrStmt.TWR2.resourceName)) {

                    unused_r2 = true;

                } else if (varName.equals(TwrStmt.TWR3.resourceName)) {

                    unused_r3 = true;

                }

            }

        }

        private JCDiagnostic unwrap(Diagnostic<? extends JavaFileObject> diagnostic) {

            if (diagnostic instanceof JCDiagnostic)

                return (JCDiagnostic) diagnostic;

            if (diagnostic instanceof ClientCodeWrapper.DiagnosticSourceUnwrapper)

                return ((ClientCodeWrapper.DiagnosticSourceUnwrapper)diagnostic).d;

            throw new IllegalArgumentException();

        }

    }

}