/*

 * 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

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 * questions.

 */

/**

 * @test

 * @bug     6945418 6993978

 * @summary Project Coin: Simplified Varargs Method Invocation

 * @author  mcimadamore

 * @run main Warn4

 */

import com.sun.source.util.JavacTask;

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

import java.net.URI;

import java.util.Arrays;

import java.util.Set;

import java.util.HashSet;

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 Warn4 {

    final static Warning[] error = null;

    final static Warning[] none = new Warning[] {};

    final static Warning[] vararg = new Warning[] { Warning.VARARGS };

    final static Warning[] unchecked = new Warning[] { Warning.UNCHECKED };

    final static Warning[] both = new Warning[] { Warning.VARARGS, Warning.UNCHECKED };

    enum Warning {

        UNCHECKED("generic.array.creation"),

        VARARGS("varargs.non.reifiable.type");

        String key;

        Warning(String key) {

            this.key = key;

        }

        boolean isSuppressed(TrustMe trustMe, SourceLevel source, SuppressLevel suppressLevelClient,

                SuppressLevel suppressLevelDecl, ModifierKind modKind) {

            switch(this) {

                case VARARGS:

                    return source == SourceLevel.JDK_6 ||

                            suppressLevelDecl == SuppressLevel.UNCHECKED ||

                            trustMe == TrustMe.TRUST;

                case UNCHECKED:

                    return suppressLevelClient == SuppressLevel.UNCHECKED ||

                        (trustMe == TrustMe.TRUST && modKind != ModifierKind.NONE && source == SourceLevel.JDK_7);

            }

            SuppressLevel supLev = this == VARARGS ?

                suppressLevelDecl :

                suppressLevelClient;

            return supLev == SuppressLevel.UNCHECKED ||

                    (trustMe == TrustMe.TRUST && modKind != ModifierKind.NONE);

        }

    }

    enum SourceLevel {

        JDK_6("6"),

        JDK_7("7");

        String sourceKey;

        SourceLevel(String sourceKey) {

            this.sourceKey = sourceKey;

        }

    }

    enum TrustMe {

        DONT_TRUST(""),

        TRUST("@java.lang.SafeVarargs");

        String anno;

        TrustMe(String anno) {

            this.anno = anno;

        }

    }

    enum ModifierKind {

        NONE(" "),

        FINAL("final "),

        STATIC("static ");

        String mod;

        ModifierKind(String mod) {

            this.mod = mod;

        }

    }

    enum SuppressLevel {

        NONE(""),

        UNCHECKED("unchecked");

        String lint;

        SuppressLevel(String lint) {

            this.lint = lint;

        }

        String getSuppressAnno() {

            return "@SuppressWarnings(\"" + lint + "\")";

        }

    }

    enum Signature {

        UNBOUND("void #name(List<?>#arity arg) { #body }",

            new Warning[][] {none, none, none, none, error}),

        INVARIANT_TVAR("<Z> void #name(List<Z>#arity arg) { #body }",

            new Warning[][] {both, both, error, both, error}),

        TVAR("<Z> void #name(Z#arity arg) { #body }",

            new Warning[][] {both, both, both, both, vararg}),

        INVARIANT("void #name(List<String>#arity arg) { #body }",

            new Warning[][] {error, error, error, both, error}),

        UNPARAMETERIZED("void #name(String#arity arg) { #body }",

            new Warning[][] {error, error, error, error, none});

        String template;

        Warning[][] warnings;

        Signature(String template, Warning[][] warnings) {

            this.template = template;

            this.warnings = warnings;

        }

        boolean isApplicableTo(Signature other) {

            return warnings[other.ordinal()] != null;

        }

        boolean giveUnchecked(Signature other) {

            return warnings[other.ordinal()] == unchecked ||

                    warnings[other.ordinal()] == both;

        }

        boolean giveVarargs(Signature other) {

            return warnings[other.ordinal()] == vararg ||

                    warnings[other.ordinal()] == both;

        }

    }

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

        for (SourceLevel sourceLevel : SourceLevel.values()) {

            for (TrustMe trustMe : TrustMe.values()) {

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

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

                        for (ModifierKind modKind : ModifierKind.values()) {

                            for (Signature vararg_meth : Signature.values()) {

                                for (Signature client_meth : Signature.values()) {

                                    if (vararg_meth.isApplicableTo(client_meth)) {

                                        test(sourceLevel,

                                                trustMe,

                                                suppressLevelClient,

                                                suppressLevelDecl,

                                                modKind,

                                                vararg_meth,

                                                client_meth);

                                    }

                                }

                            }

                        }

                    }

                }

            }

        }

    }

    // 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(SourceLevel sourceLevel, TrustMe trustMe, SuppressLevel suppressLevelClient,

            SuppressLevel suppressLevelDecl, ModifierKind modKind, Signature vararg_meth, Signature client_meth) throws Exception {

        final JavaCompiler tool = ToolProvider.getSystemJavaCompiler();

        JavaSource source = new JavaSource(trustMe, suppressLevelClient, suppressLevelDecl, modKind, vararg_meth, client_meth);

        DiagnosticChecker dc = new DiagnosticChecker();

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

                Arrays.asList("-Xlint:unchecked", "-source", sourceLevel.sourceKey),

                null, Arrays.asList(source));

        ct.generate(); //to get mandatory notes

        check(dc.warnings, sourceLevel,

                new boolean[] {vararg_meth.giveUnchecked(client_meth),

                               vararg_meth.giveVarargs(client_meth)},

                source, trustMe, suppressLevelClient, suppressLevelDecl, modKind);

    }

    static void check(Set<Warning> warnings, SourceLevel sourceLevel, boolean[] warnArr, JavaSource source,

            TrustMe trustMe, SuppressLevel suppressLevelClient, SuppressLevel suppressLevelDecl, ModifierKind modKind) {

        boolean badOutput = false;

        for (Warning wkind : Warning.values()) {

            boolean isSuppressed = wkind.isSuppressed(trustMe, sourceLevel,

                    suppressLevelClient, suppressLevelDecl, modKind);

            System.out.println("SUPPRESSED = " + isSuppressed);

            badOutput |= (warnArr[wkind.ordinal()] && !isSuppressed) != warnings.contains(wkind);

        }

        if (badOutput) {

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

                    source.getCharContent(true) +

                    "\nExpected unchecked warning: " + warnArr[0] +

                    "\nExpected unsafe vararg warning: " + warnArr[1] +

                    "\nWarnings: " + warnings +

                    "\nSource level: " + sourceLevel);

        }

    }

    static class JavaSource extends SimpleJavaFileObject {

        String source;

        public JavaSource(TrustMe trustMe, SuppressLevel suppressLevelClient, SuppressLevel suppressLevelDecl,

                ModifierKind modKind, Signature vararg_meth, Signature client_meth) {

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

            String meth1 = vararg_meth.template.replace("#arity", "...");

            meth1 = meth1.replace("#name", "m");

            meth1 = meth1.replace("#body", "");

            meth1 = trustMe.anno + "\n" + suppressLevelDecl.getSuppressAnno() + modKind.mod + meth1;

            String meth2 = client_meth.template.replace("#arity", "");

            meth2 = meth2.replace("#name", "test");

            meth2 = meth2.replace("#body", "m(arg);");

            meth2 = suppressLevelClient.getSuppressAnno() + meth2;

            source = "import java.util.List;\n" +

                     "class Test {\n" + meth1 +

                     "\n" + meth2 + "\n}\n";

        }

        @Override

        public CharSequence getCharContent(boolean ignoreEncodingErrors) {

            return source;

        }

    }

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

        Set<Warning> warnings = new HashSet<>();

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

            if (diagnostic.getKind() == Diagnostic.Kind.MANDATORY_WARNING ||

                    diagnostic.getKind() == Diagnostic.Kind.WARNING) {

                if (diagnostic.getCode().contains(Warning.VARARGS.key)) {

                    warnings.add(Warning.VARARGS);

                } else if(diagnostic.getCode().contains(Warning.UNCHECKED.key)) {

                    warnings.add(Warning.UNCHECKED);

                }

            }

        }

    }

}