/*

 * 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 7042566 8006694

 * @summary Unambiguous varargs method calls flagged as ambiguous

 *  temporarily workaround combo tests are causing time out in several platforms

 * @library ../../lib

 * @build JavacTestingAbstractThreadedTest

 * @run main/othervm T7042566

 */

// use /othervm to avoid jtreg timeout issues (CODETOOLS-7900047)

// see JDK-8006746

import java.io.File;

import java.net.URI;

import java.util.Arrays;

import java.util.Locale;

import java.util.concurrent.atomic.AtomicInteger;

import javax.tools.Diagnostic;

import javax.tools.JavaCompiler;

import javax.tools.JavaFileObject;

import javax.tools.SimpleJavaFileObject;

import javax.tools.ToolProvider;

import com.sun.source.util.JavacTask;

import com.sun.tools.classfile.Instruction;

import com.sun.tools.classfile.Attribute;

import com.sun.tools.classfile.ClassFile;

import com.sun.tools.classfile.Code_attribute;

import com.sun.tools.classfile.ConstantPool.*;

import com.sun.tools.classfile.Method;

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

public class T7042566

    extends JavacTestingAbstractThreadedTest

    implements Runnable {

    VarargsMethod m1;

    VarargsMethod m2;

    TypeConfiguration actuals;

    T7042566(TypeConfiguration m1_conf, TypeConfiguration m2_conf,

            TypeConfiguration actuals) {

        this.m1 = new VarargsMethod(m1_conf);

        this.m2 = new VarargsMethod(m2_conf);

        this.actuals = actuals;

    }

    @Override

    public void run() {

        int id = checkCount.incrementAndGet();

        final JavaCompiler tool = ToolProvider.getSystemJavaCompiler();

        JavaSource source = new JavaSource(id);

        ErrorChecker ec = new ErrorChecker();

        JavacTask ct = (JavacTask)tool.getTask(null, fm.get(), ec,

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

        ct.call();

        check(source, ec, id);

    }

    void check(JavaSource source, ErrorChecker ec, int id) {

        boolean resolutionError = false;

        VarargsMethod selectedMethod = null;

        boolean m1_applicable = m1.isApplicable(actuals);

        boolean m2_applicable = m2.isApplicable(actuals);

        if (!m1_applicable && !m2_applicable) {

            resolutionError = true;

        } else if (m1_applicable && m2_applicable) {

            //most specific

            boolean m1_moreSpecific = m1.isMoreSpecificThan(m2);

            boolean m2_moreSpecific = m2.isMoreSpecificThan(m1);

            resolutionError = m1_moreSpecific == m2_moreSpecific;

            selectedMethod = m1_moreSpecific ? m1 : m2;

        } else {

            selectedMethod = m1_applicable ?

                m1 : m2;

        }

        if (ec.errorFound != resolutionError) {

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

                    source.getCharContent(true) +

                    "\nExpected resolution error: " + resolutionError +

                    "\nFound error: " + ec.errorFound +

                    "\nCompiler diagnostics:\n" + ec.printDiags());

        } else if (!resolutionError) {

            verifyBytecode(selectedMethod, source, id);

        }

    }

    void verifyBytecode(VarargsMethod selected, JavaSource source, int id) {

        bytecodeCheckCount.incrementAndGet();

        File compiledTest = new File(String.format("Test%d.class", id));

        try {

            ClassFile cf = ClassFile.read(compiledTest);

            Method testMethod = null;

            for (Method m : cf.methods) {

                if (m.getName(cf.constant_pool).equals("test")) {

                    testMethod = m;

                    break;

                }

            }

            if (testMethod == null) {

                throw new Error("Test method not found");

            }

            Code_attribute ea =

                (Code_attribute)testMethod.attributes.get(Attribute.Code);

            if (testMethod == null) {

                throw new Error("Code attribute for test() method not found");

            }

            for (Instruction i : ea.getInstructions()) {

                if (i.getMnemonic().equals("invokevirtual")) {

                    int cp_entry = i.getUnsignedShort(1);

                    CONSTANT_Methodref_info methRef =

                        (CONSTANT_Methodref_info)cf.constant_pool.get(cp_entry);

                    String type = methRef.getNameAndTypeInfo().getType();

                    String sig = selected.parameterTypes.bytecodeSigStr;

                    if (!type.contains(sig)) {

                        throw new Error("Unexpected type method call: " +

                                        type + "" +

                                        "\nfound: " + sig +

                                        "\n" + source.getCharContent(true));

                    }

                    break;

                }

            }

        } catch (Exception e) {

            e.printStackTrace();

            throw new Error("error reading " + compiledTest +": " + e);

        }

    }

    class JavaSource extends SimpleJavaFileObject {

        static final String source_template = "class Test#ID {\n" +

                "   #V1\n" +

                "   #V2\n" +

                "   void test() { m(#E); }\n" +

                "}";

        String source;

        public JavaSource(int id) {

            super(URI.create(String.format("myfo:/Test%d.java", id)),

                    JavaFileObject.Kind.SOURCE);

            source = source_template.replaceAll("#V1", m1.toString())

                    .replaceAll("#V2", m2.toString())

                    .replaceAll("#E", actuals.expressionListStr)

                    .replaceAll("#ID", String.valueOf(id));

        }

        @Override

        public CharSequence getCharContent(boolean ignoreEncodingErrors) {

            return source;

        }

    }

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

        for (TypeConfiguration tconf1 : TypeConfiguration.values()) {

            for (TypeConfiguration tconf2 : TypeConfiguration.values()) {

                for (TypeConfiguration tconf3 : TypeConfiguration.values()) {

                    pool.execute(new T7042566(tconf1, tconf2, tconf3));

                }

            }

        }

        outWriter.println("Bytecode checks made: " + bytecodeCheckCount.get());

        checkAfterExec();

    }

    enum TypeKind {

        OBJECT("Object", "(Object)null", "Ljava/lang/Object;"),

        STRING("String", "(String)null", "Ljava/lang/String;");

        String typeString;

        String valueString;

        String bytecodeString;

        TypeKind(String typeString, String valueString, String bytecodeString) {

            this.typeString = typeString;

            this.valueString = valueString;

            this.bytecodeString = bytecodeString;

        }

        boolean isSubtypeOf(TypeKind that) {

            return that == OBJECT ||

                    (that == STRING && this == STRING);

        }

    }

    enum TypeConfiguration {

        A(TypeKind.OBJECT),

        B(TypeKind.STRING),

        AA(TypeKind.OBJECT, TypeKind.OBJECT),

        AB(TypeKind.OBJECT, TypeKind.STRING),

        BA(TypeKind.STRING, TypeKind.OBJECT),

        BB(TypeKind.STRING, TypeKind.STRING),

        AAA(TypeKind.OBJECT, TypeKind.OBJECT, TypeKind.OBJECT),

        AAB(TypeKind.OBJECT, TypeKind.OBJECT, TypeKind.STRING),

        ABA(TypeKind.OBJECT, TypeKind.STRING, TypeKind.OBJECT),

        ABB(TypeKind.OBJECT, TypeKind.STRING, TypeKind.STRING),

        BAA(TypeKind.STRING, TypeKind.OBJECT, TypeKind.OBJECT),

        BAB(TypeKind.STRING, TypeKind.OBJECT, TypeKind.STRING),

        BBA(TypeKind.STRING, TypeKind.STRING, TypeKind.OBJECT),

        BBB(TypeKind.STRING, TypeKind.STRING, TypeKind.STRING);

        List<TypeKind> typeKindList;

        String expressionListStr;

        String parameterListStr;

        String bytecodeSigStr;

        private TypeConfiguration(TypeKind... typeKindList) {

            this.typeKindList = List.from(typeKindList);

            expressionListStr = asExpressionList();

            parameterListStr = asParameterList();

            bytecodeSigStr = asBytecodeString();

        }

        private String asExpressionList() {

            StringBuilder buf = new StringBuilder();

            String sep = "";

            for (TypeKind tk : typeKindList) {

                buf.append(sep);

                buf.append(tk.valueString);

                sep = ",";

            }

            return buf.toString();

        }

        private String asParameterList() {

            StringBuilder buf = new StringBuilder();

            String sep = "";

            int count = 0;

            for (TypeKind arg : typeKindList) {

                buf.append(sep);

                buf.append(arg.typeString);

                if (count == (typeKindList.size() - 1)) {

                    buf.append("...");

                }

                buf.append(" ");

                buf.append("arg" + count++);

                sep = ",";

            }

            return buf.toString();

        }

        private String asBytecodeString() {

            StringBuilder buf = new StringBuilder();

            int count = 0;

            for (TypeKind arg : typeKindList) {

                if (count == (typeKindList.size() - 1)) {

                    buf.append("[");

                }

                buf.append(arg.bytecodeString);

                count++;

            }

            return buf.toString();

        }

    }

    static class VarargsMethod {

        TypeConfiguration parameterTypes;

        public VarargsMethod(TypeConfiguration parameterTypes) {

            this.parameterTypes = parameterTypes;

        }

        @Override

        public String toString() {

            return "void m( " + parameterTypes.parameterListStr + ") {}";

        }

        boolean isApplicable(TypeConfiguration that) {

            List<TypeKind> actuals = that.typeKindList;

            List<TypeKind> formals = parameterTypes.typeKindList;

            if ((actuals.size() - formals.size()) < -1)

                return false; //not enough args

            for (TypeKind actual : actuals) {

                if (!actual.isSubtypeOf(formals.head))

                    return false; //type mismatch

                formals = formals.tail.isEmpty() ?

                    formals :

                    formals.tail;

            }

            return true;

        }

        boolean isMoreSpecificThan(VarargsMethod that) {

            List<TypeKind> actuals = parameterTypes.typeKindList;

            List<TypeKind> formals = that.parameterTypes.typeKindList;

            int checks = 0;

            int expectedCheck = Math.max(actuals.size(), formals.size());

            while (checks < expectedCheck) {

                if (!actuals.head.isSubtypeOf(formals.head))

                    return false; //type mismatch

                formals = formals.tail.isEmpty() ?

                    formals :

                    formals.tail;

                actuals = actuals.tail.isEmpty() ?

                    actuals :

                    actuals.tail;

                checks++;

            }

            return true;

        }

    }

    static class ErrorChecker

        implements javax.tools.DiagnosticListener<JavaFileObject> {

        boolean errorFound;

        List<String> errDiags = List.nil();

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

            if (diagnostic.getKind() == Diagnostic.Kind.ERROR) {

                errDiags = errDiags

                        .append(diagnostic.getMessage(Locale.getDefault()));

                errorFound = true;

            }

        }

        String printDiags() {

            StringBuilder buf = new StringBuilder();

            for (String s : errDiags) {

                buf.append(s);

                buf.append("\n");

            }

            return buf.toString();

        }

    }

    //number of bytecode checks made while running combo tests

    static AtomicInteger bytecodeCheckCount = new AtomicInteger();

}