/*

 * Copyright (c) 2017, 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

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 * questions.

 */

/*

 * @test

 * @bug 8188225

 * @summary Check that variables of type var have a consistent model

 * @modules jdk.compiler/com.sun.tools.javac.api

 */

import com.sun.source.tree.CompilationUnitTree;

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

import java.io.IOException;

import java.net.URI;

import java.util.Arrays;

import java.util.List;

import javax.tools.JavaCompiler;

import javax.tools.JavaFileObject;

import javax.tools.SimpleJavaFileObject;

import javax.tools.ToolProvider;

import com.sun.source.tree.VariableTree;

import com.sun.source.util.TreeScanner;

import com.sun.source.util.Trees;

public class VarTree {

    private final JavaCompiler tool = ToolProvider.getSystemJavaCompiler();

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

        VarTree test = new VarTree();

        test.run("|var testVar = 0;| ",

                 "int testVar = 0");

        test.run("|var testVar = 0;| undef undef;",

                 "int testVar = 0");

        test.run("|final var testVar = 0;| ",

                 "final int testVar = 0");

        test.run("for (|var testVar| : java.util.Arrays.asList(0, 1)) {}",

                 "java.lang.Integer testVar");

        test.run("for (|final var testVar| : java.util.Arrays.asList(0, 1)) {}",

                 "final java.lang.Integer testVar");

        test.run("java.util.function.Consumer<String> c = |testVar| -> {};",

                 "java.lang.String testVar");

        test.run("java.util.function.Consumer<String> c = (|testVar|) -> {};",

                 "java.lang.String testVar");

    }

    void run(String code, String expected) throws IOException {

        String[] parts = code.split("\\|");

        if (parts.length != 3) {

            throw new IllegalStateException("Incorrect number of markers.");

        }

        String prefix = "public class Test { void test() { ";

        String src = prefix + parts[0] + parts[1] + parts[2] + " } }";

        JavacTaskImpl ct = (JavacTaskImpl) tool.getTask(null, null, d -> {},

                                                        List.of("--should-stop:at=FLOW"),

                                                        null, Arrays.asList(new MyFileObject(src)));

        Iterable<? extends CompilationUnitTree> units = ct.parse();

        ct.analyze();

        Trees trees = Trees.instance(ct);

        for (CompilationUnitTree cut : units) {

            new TreeScanner<Void, Void>() {

                @Override

                public Void visitVariable(VariableTree node, Void p) {

                    if (node.getName().contentEquals("testVar")) {

                        if (!expected.equals(node.toString())) {

                            throw new AssertionError("Unexpected tree: " + node.toString());

                        }

                        int start = (int) trees.getSourcePositions().getStartPosition(cut, node);

                        int end   = (int) trees.getSourcePositions().getEndPosition(cut, node);

                        String snip = src.substring(start, end);

                        if (start != prefix.length() + parts[0].length() || end != prefix.length() + parts[0].length() + parts[1].length()) {

                            throw new AssertionError("Unexpected span: " + snip);

                        }

                        int typeStart = (int) trees.getSourcePositions().getStartPosition(cut, node.getType());

                        int typeEnd   = (int) trees.getSourcePositions().getEndPosition(cut, node.getType());

                        if (typeStart != (-1) && typeEnd != (-1)) {

                            throw new AssertionError("Unexpected type position: " + typeStart + ", " + typeEnd);

                        }

                    }

                    return super.visitVariable(node, p);

                }

            }.scan(cut, null);

        }

    }

    class MyFileObject extends SimpleJavaFileObject {

        private String text;

        public MyFileObject(String text) {

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

            this.text = text;

        }

        @Override

        public CharSequence getCharContent(boolean ignoreEncodingErrors) {

            return text;

        }

    }

}