/*

 * Copyright (c) 2002, 2019, 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.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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.

 */

package com.sun.tools.javac.code;

import java.util.*;

import javax.lang.model.SourceVersion;

import static javax.lang.model.SourceVersion.*;

import com.sun.tools.javac.jvm.Target;

import com.sun.tools.javac.resources.CompilerProperties.Errors;

import com.sun.tools.javac.resources.CompilerProperties.Fragments;

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

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

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

import static com.sun.tools.javac.main.Option.*;

/** The source language version accepted.

 *

 *  <p><b>This is NOT part of any supported API.

 *  If you write code that depends on this, you do so at your own risk.

 *  This code and its internal interfaces are subject to change or

 *  deletion without notice.</b>

 */

public enum Source {

    /** 1.0 had no inner classes, and so could not pass the JCK. */

    // public static final Source JDK1_0 =              new Source("1.0");

    /** 1.1 did not have strictfp, and so could not pass the JCK. */

    // public static final Source JDK1_1 =              new Source("1.1");

    /** 1.2 introduced strictfp. */

    JDK1_2("1.2"),

    /** 1.3 is the same language as 1.2. */

    JDK1_3("1.3"),

    /** 1.4 introduced assert. */

    JDK1_4("1.4"),

    /** 1.5 introduced generics, attributes, foreach, boxing, static import,

     *  covariant return, enums, varargs, et al. */

    JDK5("5"),

    /** 1.6 reports encoding problems as errors instead of warnings. */

    JDK6("6"),

    /** 1.7 introduced try-with-resources, multi-catch, string switch, etc. */

    JDK7("7"),

    /** 1.8 lambda expressions and default methods. */

    JDK8("8"),

    /** 1.9 modularity. */

    JDK9("9"),

    /** 1.10 local-variable type inference (var). */

    JDK10("10"),

    /** 1.11 local-variable syntax for lambda parameters */

    JDK11("11"),

    /** 12, no language features; switch expression in preview */

    JDK12("12"),

    /**

     * 13, no language features; text blocks and revised switch

     * expressions in preview

     */

    JDK13("13"),

    /**

     * 14, switch expressions

     */

    JDK14("14");

    private static final Context.Key<Source> sourceKey = new Context.Key<>();

    public static Source instance(Context context) {

        Source instance = context.get(sourceKey);

        if (instance == null) {

            Options options = Options.instance(context);

            String sourceString = options.get(SOURCE);

            if (sourceString != null) instance = lookup(sourceString);

            if (instance == null) instance = DEFAULT;

            context.put(sourceKey, instance);

        }

        return instance;

    }

    public final String name;

    private static final Map<String,Source> tab = new HashMap<>();

    static {

        for (Source s : values()) {

            tab.put(s.name, s);

        }

        tab.put("1.5", JDK5); // Make 5 an alias for 1.5

        tab.put("1.6", JDK6); // Make 6 an alias for 1.6

        tab.put("1.7", JDK7); // Make 7 an alias for 1.7

        tab.put("1.8", JDK8); // Make 8 an alias for 1.8

        tab.put("1.9", JDK9); // Make 9 an alias for 1.9

        tab.put("1.10", JDK10); // Make 10 an alias for 1.10

        // Decline to make 1.11 an alias for 11.

    }

    private Source(String name) {

        this.name = name;

    }

    public static final Source MIN = Source.JDK7;

    private static final Source MAX = values()[values().length - 1];

    public static final Source DEFAULT = MAX;

    public static Source lookup(String name) {

        return tab.get(name);

    }

    public boolean isSupported() {

        return this.compareTo(MIN) >= 0;

    }

    public Target requiredTarget() {

        if (this.compareTo(JDK14) >= 0) return Target.JDK1_14;

        if (this.compareTo(JDK13) >= 0) return Target.JDK1_13;

        if (this.compareTo(JDK12) >= 0) return Target.JDK1_12;

        if (this.compareTo(JDK11) >= 0) return Target.JDK1_11;

        if (this.compareTo(JDK10) >= 0) return Target.JDK1_10;

        if (this.compareTo(JDK9) >= 0) return Target.JDK1_9;

        if (this.compareTo(JDK8) >= 0) return Target.JDK1_8;

        if (this.compareTo(JDK7) >= 0) return Target.JDK1_7;

        if (this.compareTo(JDK6) >= 0) return Target.JDK1_6;

        if (this.compareTo(JDK5) >= 0) return Target.JDK1_5;

        if (this.compareTo(JDK1_4) >= 0) return Target.JDK1_4;

        return Target.JDK1_1;

    }

    /**

     * Models a feature of the Java programming language. Each feature can be associated with a

     * minimum source level, a maximum source level and a diagnostic fragment describing the feature,

     * which is used to generate error messages of the kind {@code feature XYZ not supported in source N}.

     */

    public enum Feature {

        DIAMOND(JDK7, Fragments.FeatureDiamond, DiagKind.NORMAL),

        MODULES(JDK9, Fragments.FeatureModules, DiagKind.PLURAL),

        EFFECTIVELY_FINAL_VARIABLES_IN_TRY_WITH_RESOURCES(JDK9, Fragments.FeatureVarInTryWithResources, DiagKind.PLURAL),

        DEPRECATION_ON_IMPORT(MIN, JDK8),

        POLY(JDK8),

        LAMBDA(JDK8, Fragments.FeatureLambda, DiagKind.PLURAL),

        METHOD_REFERENCES(JDK8, Fragments.FeatureMethodReferences, DiagKind.PLURAL),

        DEFAULT_METHODS(JDK8, Fragments.FeatureDefaultMethods, DiagKind.PLURAL),

        STATIC_INTERFACE_METHODS(JDK8, Fragments.FeatureStaticIntfMethods, DiagKind.PLURAL),

        STATIC_INTERFACE_METHODS_INVOKE(JDK8, Fragments.FeatureStaticIntfMethodInvoke, DiagKind.PLURAL),

        STRICT_METHOD_CLASH_CHECK(JDK8),

        EFFECTIVELY_FINAL_IN_INNER_CLASSES(JDK8),

        TYPE_ANNOTATIONS(JDK8, Fragments.FeatureTypeAnnotations, DiagKind.PLURAL),

        ANNOTATIONS_AFTER_TYPE_PARAMS(JDK8, Fragments.FeatureAnnotationsAfterTypeParams, DiagKind.PLURAL),

        REPEATED_ANNOTATIONS(JDK8, Fragments.FeatureRepeatableAnnotations, DiagKind.PLURAL),

        INTERSECTION_TYPES_IN_CAST(JDK8, Fragments.FeatureIntersectionTypesInCast, DiagKind.PLURAL),

        GRAPH_INFERENCE(JDK8),

        FUNCTIONAL_INTERFACE_MOST_SPECIFIC(JDK8),

        POST_APPLICABILITY_VARARGS_ACCESS_CHECK(JDK8),

        MAP_CAPTURES_TO_BOUNDS(MIN, JDK7),

        PRIVATE_SAFE_VARARGS(JDK9),

        DIAMOND_WITH_ANONYMOUS_CLASS_CREATION(JDK9, Fragments.FeatureDiamondAndAnonClass, DiagKind.NORMAL),

        UNDERSCORE_IDENTIFIER(MIN, JDK8),

        PRIVATE_INTERFACE_METHODS(JDK9, Fragments.FeaturePrivateIntfMethods, DiagKind.PLURAL),

        LOCAL_VARIABLE_TYPE_INFERENCE(JDK10),

        VAR_SYNTAX_IMPLICIT_LAMBDAS(JDK11, Fragments.FeatureVarSyntaxInImplicitLambda, DiagKind.PLURAL),

        IMPORT_ON_DEMAND_OBSERVABLE_PACKAGES(JDK1_2, JDK8),

        SWITCH_MULTIPLE_CASE_LABELS(JDK14, Fragments.FeatureMultipleCaseLabels, DiagKind.PLURAL),

        SWITCH_RULE(JDK14, Fragments.FeatureSwitchRules, DiagKind.PLURAL),

        SWITCH_EXPRESSION(JDK14, Fragments.FeatureSwitchExpressions, DiagKind.PLURAL),

        enum DiagKind {

            NORMAL,

            PLURAL;

        }

        private final Source minLevel;

        private final Source maxLevel;

        private final Fragment optFragment;

        private final DiagKind optKind;

        Feature(Source minLevel) {

            this(minLevel, null, null);

        }

        Feature(Source minLevel, Fragment optFragment, DiagKind optKind) {

            this(minLevel, MAX, optFragment, optKind);

        }

        Feature(Source minLevel, Source maxLevel) {

            this(minLevel, maxLevel, null, null);

        }

        Feature(Source minLevel, Source maxLevel, Fragment optFragment, DiagKind optKind) {

            this.minLevel = minLevel;

            this.maxLevel = maxLevel;

            this.optFragment = optFragment;

            this.optKind = optKind;

        }

        public boolean allowedInSource(Source source) {

            return source.compareTo(minLevel) >= 0 &&

                    source.compareTo(maxLevel) <= 0;

        }

        public boolean isPlural() {

            Assert.checkNonNull(optKind);

            return optKind == DiagKind.PLURAL;

        }

        public Fragment nameFragment() {

            Assert.checkNonNull(optFragment);

            return optFragment;

        }

        public Fragment fragment(String sourceName) {

            Assert.checkNonNull(optFragment);

            return optKind == DiagKind.NORMAL ?

                    Fragments.FeatureNotSupportedInSource(optFragment, sourceName, minLevel.name) :

                    Fragments.FeatureNotSupportedInSourcePlural(optFragment, sourceName, minLevel.name);

        }

        public Error error(String sourceName) {

            Assert.checkNonNull(optFragment);

            return optKind == DiagKind.NORMAL ?

                    Errors.FeatureNotSupportedInSource(optFragment, sourceName, minLevel.name) :

                    Errors.FeatureNotSupportedInSourcePlural(optFragment, sourceName, minLevel.name);

        }

    }

    public static SourceVersion toSourceVersion(Source source) {

        switch(source) {

        case JDK1_2:

            return RELEASE_2;

        case JDK1_3:

            return RELEASE_3;

        case JDK1_4:

            return RELEASE_4;

        case JDK5:

            return RELEASE_5;

        case JDK6:

            return RELEASE_6;

        case JDK7:

            return RELEASE_7;

        case JDK8:

            return RELEASE_8;

        case JDK9:

            return RELEASE_9;

        case JDK10:

            return RELEASE_10;

        case JDK11:

            return RELEASE_11;

        case JDK12:

            return RELEASE_12;

        case JDK13:

            return RELEASE_13;

        case JDK14:

            return RELEASE_14;

        default:

            return null;

        }

    }

}