/*

 * Copyright (c) 1997, 2013, 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.

 */

import com.sun.source.util.TreePath;

import java.lang.reflect.Modifier;

import com.sun.javadoc.*;

import com.sun.tools.javac.code.Flags;

import com.sun.tools.javac.code.Symbol.ClassSymbol;

import com.sun.tools.javac.code.Symbol.VarSymbol;

import static com.sun.tools.javac.code.TypeTag.BOOLEAN;

/**

 * Represents a field in a java class.

 *

 *  <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>

 *

 * @see MemberDocImpl

 *

 * @since 1.2

 * @author Robert Field

 * @author Neal Gafter (rewrite)

 * @author Scott Seligman (generics, enums, annotations)

 */

public class FieldDocImpl extends MemberDocImpl implements FieldDoc {

    protected final VarSymbol sym;

    /**

     * Constructor.

     */

    public FieldDocImpl(DocEnv env, VarSymbol sym, TreePath treePath) {

        super(env, sym, treePath);

        this.sym = sym;

    }

    /**

     * Constructor.

     */

    public FieldDocImpl(DocEnv env, VarSymbol sym) {

        this(env, sym, null);

    }

    /**

     * Returns the flags in terms of javac's flags

     */

    protected long getFlags() {

        return sym.flags();

    }

    /**

     * Identify the containing class

     */

    protected ClassSymbol getContainingClass() {

        return sym.enclClass();

    }

    /**

     * Get type of this field.

     */

    public com.sun.javadoc.Type type() {

        return TypeMaker.getType(env, sym.type, false);

    }

    /**

     * Get the value of a constant field.

     *

     * @return the value of a constant field. The value is

     * automatically wrapped in an object if it has a primitive type.

     * If the field is not constant, returns null.

     */

    public Object constantValue() {

        Object result = sym.getConstValue();

        if (result != null && sym.type.hasTag(BOOLEAN))

            // javac represents false and true as Integers 0 and 1

            result = Boolean.valueOf(((Integer)result).intValue() != 0);

        return result;

    }

    /**

     * Get the value of a constant field.

     *

     * @return the text of a Java language expression whose value

     * is the value of the constant. The expression uses no identifiers

     * other than primitive literals. If the field is

     * not constant, returns null.

     */

    public String constantValueExpression() {

        return constantValueExpression(constantValue());

    }

    /**

     * A static version of the above.

     */

    static String constantValueExpression(Object cb) {

        if (cb == null) return null;

        if (cb instanceof Character) return sourceForm(((Character)cb).charValue());

        if (cb instanceof Byte) return sourceForm(((Byte)cb).byteValue());

        if (cb instanceof String) return sourceForm((String)cb);

        if (cb instanceof Double) return sourceForm(((Double)cb).doubleValue(), 'd');

        if (cb instanceof Float) return sourceForm(((Float)cb).doubleValue(), 'f');

        if (cb instanceof Long) return cb + "L";

        return cb.toString(); // covers int, short

    }

        // where

        private static String sourceForm(double v, char suffix) {

            if (Double.isNaN(v))

                return "0" + suffix + "/0" + suffix;

            if (v == Double.POSITIVE_INFINITY)

                return "1" + suffix + "/0" + suffix;

            if (v == Double.NEGATIVE_INFINITY)

                return "-1" + suffix + "/0" + suffix;

            return v + (suffix == 'f' || suffix == 'F' ? "" + suffix : "");

        }

        private static String sourceForm(char c) {

            StringBuilder buf = new StringBuilder(8);

            buf.append('\'');

            sourceChar(c, buf);

            buf.append('\'');

            return buf.toString();

        }

        private static String sourceForm(byte c) {

            return "0x" + Integer.toString(c & 0xff, 16);

        }

        private static String sourceForm(String s) {

            StringBuilder buf = new StringBuilder(s.length() + 5);

            buf.append('\"');

            for (int i=0; i<s.length(); i++) {

                char c = s.charAt(i);

                sourceChar(c, buf);

            }

            buf.append('\"');

            return buf.toString();

        }

        private static void sourceChar(char c, StringBuilder buf) {

            switch (c) {

            case '\b': buf.append("\\b"); return;

            case '\t': buf.append("\\t"); return;

            case '\n': buf.append("\\n"); return;

            case '\f': buf.append("\\f"); return;

            case '\r': buf.append("\\r"); return;

            case '\"': buf.append("\\\""); return;

            case '\'': buf.append("\\\'"); return;

            case '\\': buf.append("\\\\"); return;

            default:

                if (isPrintableAscii(c)) {

                    buf.append(c); return;

                }

                unicodeEscape(c, buf);

                return;

            }

        }

        private static void unicodeEscape(char c, StringBuilder buf) {

            final String chars = "0123456789abcdef";

            buf.append("\\u");

            buf.append(chars.charAt(15 & (c>>12)));

            buf.append(chars.charAt(15 & (c>>8)));

            buf.append(chars.charAt(15 & (c>>4)));

            buf.append(chars.charAt(15 & (c>>0)));

        }

        private static boolean isPrintableAscii(char c) {

            return c >= ' ' && c <= '~';

        }

    /**

     * Return true if this field is included in the active set.

     */

    public boolean isIncluded() {

        return containingClass().isIncluded() && env.shouldDocument(sym);

    }

    /**

     * Is this Doc item a field (but not an enum constant?

     */

    @Override

    public boolean isField() {

        return !isEnumConstant();

    }

    /**

     * Is this Doc item an enum constant?

     * (For legacy doclets, return false.)

     */

    @Override

    public boolean isEnumConstant() {

        return (getFlags() & Flags.ENUM) != 0 &&

               !env.legacyDoclet;

    }

    /**

     * Return true if this field is transient

     */

    public boolean isTransient() {

        return Modifier.isTransient(getModifiers());

    }

    /**

     * Return true if this field is volatile

     */

    public boolean isVolatile() {

        return Modifier.isVolatile(getModifiers());

    }

    /**

     * Returns true if this field was synthesized by the compiler.

     */

    public boolean isSynthetic() {

        return (getFlags() & Flags.SYNTHETIC) != 0;

    }

    /**

     * Return the serialField tags in this FieldDocImpl item.

     *

     * @return an array of <tt>SerialFieldTagImpl</tt> containing all

     *         <code>&#64;serialField</code> tags.

     */

    public SerialFieldTag[] serialFieldTags() {

        return comment().serialFieldTags();

    }

    public String name() {

        if (name == null) {

            name = sym.name.toString();

        }

        return name;

    }

    private String name;

    public String qualifiedName() {

        if (qualifiedName == null) {

            qualifiedName = sym.enclClass().getQualifiedName() + "." + name();

        }

        return qualifiedName;

    }

    private String qualifiedName;

    /**

     * Return the source position of the entity, or null if

     * no position is available.

     */

    @Override

    public SourcePosition position() {

        if (sym.enclClass().sourcefile == null) return null;

        return SourcePositionImpl.make(sym.enclClass().sourcefile,

                                       (tree==null) ? 0 : tree.pos,

                                       lineMap);

    }

}