/*

 * 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 7115050

 * @summary Add parser support for lambda expressions

 */

import com.sun.source.util.JavacTask;

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 LambdaParserTest {

    static int checkCount = 0;

    enum LambdaKind {

        NILARY_EXPR("()->x"),

        NILARY_STMT("()->{ return x; }"),

        ONEARY_SHORT_EXPR("x->x"),

        ONEARY_SHORT_STMT("x->{ return x; }"),

        ONEARY_EXPR("(#M1 #T1 x)->x"),

        ONEARY_STMT("(#M1 #T1 x)->{ return x; }"),

        TWOARY_EXPR("(#M1 #T1 x, #M2 #T2 y)->x"),

        TWOARY_STMT("(#M1 #T1 x, #M2 #T2 y)->{ return x; }");

        String lambdaTemplate;

        LambdaKind(String lambdaTemplate) {

            this.lambdaTemplate = lambdaTemplate;

        }

        String getLambdaString(LambdaParameterKind pk1, LambdaParameterKind pk2,

                ModifierKind mk1, ModifierKind mk2) {

            return lambdaTemplate.replaceAll("#M1", mk1.modifier)

                    .replaceAll("#M2", mk2.modifier)

                    .replaceAll("#T1", pk1.parameterType)

                    .replaceAll("#T2", pk2.parameterType);

        }

        int arity() {

            switch (this) {

                case NILARY_EXPR:

                case NILARY_STMT: return 0;

                case ONEARY_SHORT_EXPR:

                case ONEARY_SHORT_STMT:

                case ONEARY_EXPR:

                case ONEARY_STMT: return 1;

                case TWOARY_EXPR:

                case TWOARY_STMT: return 2;

                default: throw new AssertionError("Invalid lambda kind " + this);

            }

        }

        boolean isShort() {

            return this == ONEARY_SHORT_EXPR ||

                    this == ONEARY_SHORT_STMT;

        }

    }

    enum LambdaParameterKind {

        IMPLICIT(""),

        EXPLIICT_SIMPLE("A"),

        EXPLICIT_VARARGS("A..."),

        EXPLICIT_GENERIC1("A<X>"),

        EXPLICIT_GENERIC3("A<? extends X, ? super Y>");

        String parameterType;

        LambdaParameterKind(String parameterType) {

            this.parameterType = parameterType;

        }

        boolean explicit() {

            return this != IMPLICIT;

        }

    }

    enum ModifierKind {

        NONE(""),

        FINAL("final"),

        PUBLIC("public");

        String modifier;

        ModifierKind(String modifier) {

            this.modifier = modifier;

        }

        boolean compatibleWith(LambdaParameterKind pk) {

            switch (this) {

                case PUBLIC: return false;

                case FINAL: return pk != LambdaParameterKind.IMPLICIT;

                case NONE: return true;

                default: throw new AssertionError("Invalid modifier kind " + this);

            }

        }

    }

    enum ExprKind {

        NONE("#L#S"),

        SINGLE_PAREN1("(#L#S)"),

        SINGLE_PAREN2("(#L)#S"),

        DOUBLE_PAREN1("((#L#S))"),

        DOUBLE_PAREN2("((#L)#S)"),

        DOUBLE_PAREN3("((#L))#S");

        String expressionTemplate;

        ExprKind(String expressionTemplate) {

            this.expressionTemplate = expressionTemplate;

        }

        String expressionString(LambdaParameterKind pk1, LambdaParameterKind pk2,

                ModifierKind mk1, ModifierKind mk2, LambdaKind lk, SubExprKind sk) {

            return expressionTemplate.replaceAll("#L", lk.getLambdaString(pk1, pk2, mk1, mk2))

                    .replaceAll("#S", sk.subExpression);

        }

    }

    enum SubExprKind {

        NONE(""),

        SELECT_FIELD(".f"),

        SELECT_METHOD(".f()"),

        SELECT_NEW(".new Foo()"),

        POSTINC("++"),

        POSTDEC("--");

        String subExpression;

        SubExprKind(String subExpression) {

            this.subExpression = subExpression;

        }

    }

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

        //create default shared JavaCompiler - reused across multiple compilations

        JavaCompiler comp = ToolProvider.getSystemJavaCompiler();

        StandardJavaFileManager fm = comp.getStandardFileManager(null, null, null);

        for (LambdaKind lk : LambdaKind.values()) {

            for (LambdaParameterKind pk1 : LambdaParameterKind.values()) {

                if (lk.arity() < 1 && pk1 != LambdaParameterKind.IMPLICIT) continue;

                for (LambdaParameterKind pk2 : LambdaParameterKind.values()) {

                    if (lk.arity() < 2 && pk2 != LambdaParameterKind.IMPLICIT) continue;

                    for (ModifierKind mk1 : ModifierKind.values()) {

                        if (mk1 != ModifierKind.NONE && lk.isShort()) continue;

                        if (lk.arity() < 1 && mk1 != ModifierKind.NONE) continue;

                        for (ModifierKind mk2 : ModifierKind.values()) {

                            if (lk.arity() < 2 && mk2 != ModifierKind.NONE) continue;

                            for (SubExprKind sk : SubExprKind.values()) {

                                for (ExprKind ek : ExprKind.values()) {

                                    new LambdaParserTest(pk1, pk2, mk1, mk2, lk, sk, ek)

                                            .run(comp, fm);

                                }

                            }

                        }

                    }

                }

            }

        }

        System.out.println("Total check executed: " + checkCount);

    }

    LambdaParameterKind pk1;

    LambdaParameterKind pk2;

    ModifierKind mk1;

    ModifierKind mk2;

    LambdaKind lk;

    SubExprKind sk;

    ExprKind ek;

    JavaSource source;

    DiagnosticChecker diagChecker;

    LambdaParserTest(LambdaParameterKind pk1, LambdaParameterKind pk2, ModifierKind mk1,

            ModifierKind mk2, LambdaKind lk, SubExprKind sk, ExprKind ek) {

        this.pk1 = pk1;

        this.pk2 = pk2;

        this.mk1 = mk1;

        this.mk2 = mk2;

        this.lk = lk;

        this.sk = sk;

        this.ek = ek;

        this.source = new JavaSource();

        this.diagChecker = new DiagnosticChecker();

    }

    class JavaSource extends SimpleJavaFileObject {

        String template = "class Test {\n" +

                          "   SAM s = #E;\n" +

                          "}";

        String source;

        public JavaSource() {

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

            source = template.replaceAll("#E", ek.expressionString(pk1, pk2, mk1, mk2, lk, sk));

        }

        @Override

        public CharSequence getCharContent(boolean ignoreEncodingErrors) {

            return source;

        }

    }

    void run(JavaCompiler tool, StandardJavaFileManager fm) throws Exception {

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

                Arrays.asList("-XDallowLambda"), null, Arrays.asList(source));

        try {

            ct.parse();

        } catch (Throwable ex) {

            throw new AssertionError("Error thron when parsing the following source:\n" + source.getCharContent(true));

        }

        check();

    }

    void check() {

        checkCount++;

        boolean errorExpected = (lk.arity() > 0 && !mk1.compatibleWith(pk1)) ||

                (lk.arity() > 1 && !mk2.compatibleWith(pk2));

        if (lk.arity() == 2 &&

                (pk1.explicit() != pk2.explicit() ||

                pk1 == LambdaParameterKind.EXPLICIT_VARARGS)) {

            errorExpected = true;

        }

        if (errorExpected != diagChecker.errorFound) {

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

                source.getCharContent(true) +

                "\nFound error: " + diagChecker.errorFound +

                "\nExpected error: " + errorExpected);

        }

    }

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

        boolean errorFound;

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

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

                errorFound = true;

            }

        }

    }

}