/***
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2007 INRIA, France Telecom
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */
package alterrs.asm;

/**
 * An {@link FieldVisitor} that generates Java fields in bytecode form.
 * 
 * @author Eric Bruneton
 */
final class FieldWriter implements FieldVisitor {

	/**
	 * Next field writer (see {@link ClassWriter#firstField firstField}).
	 */
	FieldWriter next;

	/**
	 * The class writer to which this field must be added.
	 */
	private final ClassWriter cw;

	/**
	 * Access flags of this field.
	 */
	private final int access;

	/**
	 * The index of the constant pool item that contains the name of this
	 * method.
	 */
	private final int name;

	/**
	 * The index of the constant pool item that contains the descriptor of this
	 * field.
	 */
	private final int desc;

	/**
	 * The index of the constant pool item that contains the signature of this
	 * field.
	 */
	private int signature;

	/**
	 * The index of the constant pool item that contains the constant value of
	 * this field.
	 */
	private int value;

	/**
	 * The runtime visible annotations of this field. May be <tt>null</tt>.
	 */
	private AnnotationWriter anns;

	/**
	 * The runtime invisible annotations of this field. May be <tt>null</tt>.
	 */
	private AnnotationWriter ianns;

	/**
	 * The non standard attributes of this field. May be <tt>null</tt>.
	 */
	private Attribute attrs;

	// ------------------------------------------------------------------------
	// Constructor
	// ------------------------------------------------------------------------

	/**
	 * Constructs a new {@link FieldWriter}.
	 * 
	 * @param cw
	 *            the class writer to which this field must be added.
	 * @param access
	 *            the field's access flags (see {@link Opcodes}).
	 * @param name
	 *            the field's name.
	 * @param desc
	 *            the field's descriptor (see {@link Type}).
	 * @param signature
	 *            the field's signature. May be <tt>null</tt>.
	 * @param value
	 *            the field's constant value. May be <tt>null</tt>.
	 */
	FieldWriter(final ClassWriter cw, final int access, final String name,
			final String desc, final String signature, final Object value) {
		if (cw.firstField == null) {
			cw.firstField = this;
		} else {
			cw.lastField.next = this;
		}
		cw.lastField = this;
		this.cw = cw;
		this.access = access;
		this.name = cw.newUTF8(name);
		this.desc = cw.newUTF8(desc);
		if (ClassReader.SIGNATURES && signature != null) {
			this.signature = cw.newUTF8(signature);
		}
		if (value != null) {
			this.value = cw.newConstItem(value).index;
		}
	}

	// ------------------------------------------------------------------------
	// Implementation of the FieldVisitor interface
	// ------------------------------------------------------------------------

	public AnnotationVisitor visitAnnotation(final String desc,
			final boolean visible) {
		if (!ClassReader.ANNOTATIONS) {
			return null;
		}
		ByteVector bv = new ByteVector();
		// write type, and reserve space for values count
		bv.putShort(cw.newUTF8(desc)).putShort(0);
		AnnotationWriter aw = new AnnotationWriter(cw, true, bv, bv, 2);
		if (visible) {
			aw.next = anns;
			anns = aw;
		} else {
			aw.next = ianns;
			ianns = aw;
		}
		return aw;
	}

	public void visitAttribute(final Attribute attr) {
		attr.next = attrs;
		attrs = attr;
	}

	public void visitEnd() {
	}

	// ------------------------------------------------------------------------
	// Utility methods
	// ------------------------------------------------------------------------

	/**
	 * Returns the size of this field.
	 * 
	 * @return the size of this field.
	 */
	int getSize() {
		int size = 8;
		if (value != 0) {
			cw.newUTF8("ConstantValue");
			size += 8;
		}
		if ((access & Opcodes.ACC_SYNTHETIC) != 0
				&& ((cw.version & 0xFFFF) < Opcodes.V1_5 || (access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) != 0)) {
			cw.newUTF8("Synthetic");
			size += 6;
		}
		if ((access & Opcodes.ACC_DEPRECATED) != 0) {
			cw.newUTF8("Deprecated");
			size += 6;
		}
		if (ClassReader.SIGNATURES && signature != 0) {
			cw.newUTF8("Signature");
			size += 8;
		}
		if (ClassReader.ANNOTATIONS && anns != null) {
			cw.newUTF8("RuntimeVisibleAnnotations");
			size += 8 + anns.getSize();
		}
		if (ClassReader.ANNOTATIONS && ianns != null) {
			cw.newUTF8("RuntimeInvisibleAnnotations");
			size += 8 + ianns.getSize();
		}
		if (attrs != null) {
			size += attrs.getSize(cw, null, 0, -1, -1);
		}
		return size;
	}

	/**
	 * Puts the content of this field into the given byte vector.
	 * 
	 * @param out
	 *            where the content of this field must be put.
	 */
	void put(final ByteVector out) {
		int mask = Opcodes.ACC_DEPRECATED
				| ClassWriter.ACC_SYNTHETIC_ATTRIBUTE
				| ((access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) / (ClassWriter.ACC_SYNTHETIC_ATTRIBUTE / Opcodes.ACC_SYNTHETIC));
		out.putShort(access & ~mask).putShort(name).putShort(desc);
		int attributeCount = 0;
		if (value != 0) {
			++attributeCount;
		}
		if ((access & Opcodes.ACC_SYNTHETIC) != 0
				&& ((cw.version & 0xFFFF) < Opcodes.V1_5 || (access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) != 0)) {
			++attributeCount;
		}
		if ((access & Opcodes.ACC_DEPRECATED) != 0) {
			++attributeCount;
		}
		if (ClassReader.SIGNATURES && signature != 0) {
			++attributeCount;
		}
		if (ClassReader.ANNOTATIONS && anns != null) {
			++attributeCount;
		}
		if (ClassReader.ANNOTATIONS && ianns != null) {
			++attributeCount;
		}
		if (attrs != null) {
			attributeCount += attrs.getCount();
		}
		out.putShort(attributeCount);
		if (value != 0) {
			out.putShort(cw.newUTF8("ConstantValue"));
			out.putInt(2).putShort(value);
		}
		if ((access & Opcodes.ACC_SYNTHETIC) != 0
				&& ((cw.version & 0xFFFF) < Opcodes.V1_5 || (access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) != 0)) {
			out.putShort(cw.newUTF8("Synthetic")).putInt(0);
		}
		if ((access & Opcodes.ACC_DEPRECATED) != 0) {
			out.putShort(cw.newUTF8("Deprecated")).putInt(0);
		}
		if (ClassReader.SIGNATURES && signature != 0) {
			out.putShort(cw.newUTF8("Signature"));
			out.putInt(2).putShort(signature);
		}
		if (ClassReader.ANNOTATIONS && anns != null) {
			out.putShort(cw.newUTF8("RuntimeVisibleAnnotations"));
			anns.put(out);
		}
		if (ClassReader.ANNOTATIONS && ianns != null) {
			out.putShort(cw.newUTF8("RuntimeInvisibleAnnotations"));
			ianns.put(out);
		}
		if (attrs != null) {
			attrs.put(cw, null, 0, -1, -1, out);
		}
	}
}
