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// Copyright (c) 2003-2014, Jodd Team (jodd.org). All Rights Reserved.

package jodd.asm;

import jodd.util.StringUtil;
import jodd.asm5.Opcodes;
import jodd.asm5.signature.SignatureVisitor;

/**
 * A {@link SignatureVisitor} that prints a disassembled view of the signature
 * it visits.

 * Changes made by Igor (http://jodd.org):
 * 
 *    removed final for the class
 *    some private scopes made protected
 *    added method getExceptionsArray()
 *    public constructor change to accept boolean
 *    use AsmUtil constants
 *    use StringBuilder instead of StringBuffer
 * 
 *
 * @author Eugene Kuleshov
 * @author Eric Bruneton
 */
public class TraceSignatureVisitor extends SignatureVisitor {

	protected final StringBuilder declaration;       // jodd

    protected boolean isInterface;                  // jodd

    private boolean seenFormalParameter;

    private boolean seenInterfaceBound;

    private boolean seenParameter;

    private boolean seenInterface;

    protected StringBuilder returnType;              // jodd

    protected StringBuilder exceptions;              // jodd

    /**
     * Stack used to keep track of class types that have arguments. Each element
     * of this stack is a boolean encoded in one bit. The top of the stack is
     * the lowest order bit. Pushing false = *2, pushing true = *2+1, popping =
     * /2.
     */
    protected int argumentStack;                    // jodd

    /**
     * Stack used to keep track of array class types. Each element of this stack
     * is a boolean encoded in one bit. The top of the stack is the lowest order
     * bit. Pushing false = *2, pushing true = *2+1, popping = /2.
     */
    protected int arrayStack;                       // jodd

    private String separator = "";

    public TraceSignatureVisitor(final StringBuilder buf, boolean isInterface) {		// jodd
        super(Opcodes.ASM5);
        this.isInterface = isInterface;
        this.declaration = buf;
    }

    protected TraceSignatureVisitor(final StringBuilder buf) {	// jodd
        super(Opcodes.ASM5);
        this.declaration = buf;
    }

    @Override
    public void visitFormalTypeParameter(final String name) {
        declaration.append(seenFormalParameter ? ", " : "<").append(name);
        seenFormalParameter = true;
        seenInterfaceBound = false;
    }

    @Override
    public SignatureVisitor visitClassBound() {
        separator = " extends ";
        startType();
        return this;
    }

    @Override
    public SignatureVisitor visitInterfaceBound() {
        separator = seenInterfaceBound ? ", " : " extends ";
        seenInterfaceBound = true;
        startType();
        return this;
    }

    @Override
    public SignatureVisitor visitSuperclass() {
        endFormals();
        separator = " extends ";
        startType();
        return this;
    }

    @Override
    public SignatureVisitor visitInterface() {
        separator = seenInterface ? ", " : isInterface ? " extends "
                : " implements ";
        seenInterface = true;
        startType();
        return this;
    }

    @Override
    public SignatureVisitor visitParameterType() {
        endFormals();
        if (seenParameter) {
            declaration.append(", ");
        } else {
            seenParameter = true;
            declaration.append('(');
        }
        startType();
        return this;
    }

    @Override
    public SignatureVisitor visitReturnType() {
        endFormals();
        if (seenParameter) {
            seenParameter = false;
        } else {
            declaration.append('(');
        }
        declaration.append(')');
        returnType = new StringBuilder();
        return new TraceSignatureVisitor(returnType);
    }

    @Override
    public SignatureVisitor visitExceptionType() {
        if (exceptions == null) {
            exceptions = new StringBuilder();
        } else {
            exceptions.append(", ");
        }
        // startType();
        return new TraceSignatureVisitor(exceptions);
    }

    @Override
    public void visitBaseType(final char descriptor) {
        switch (descriptor) {
        case 'V':
            declaration.append("void");
            break;
        case 'B':
            declaration.append("byte");
            break;
        case 'J':
            declaration.append("long");
            break;
        case 'Z':
            declaration.append("boolean");
            break;
        case 'I':
            declaration.append("int");
            break;
        case 'S':
            declaration.append("short");
            break;
        case 'C':
            declaration.append("char");
            break;
        case 'F':
            declaration.append("float");
            break;
        // case 'D':
        default:
            declaration.append("double");
            break;
        }
        endType();
    }

    @Override
    public void visitTypeVariable(final String name) {
        declaration.append(name);
        endType();
    }

    @Override
    public SignatureVisitor visitArrayType() {
        startType();
        arrayStack |= 1;
        return this;
    }

    @Override
    public void visitClassType(final String name) {
        if (AsmUtil.SIGNATURE_JAVA_LANG_OBJECT.equals(name)) {		// jodd
            // Map
            // or
            // abstract public V get(Object key); (seen in Dictionary.class)
            // should have Object
            // but java.lang.String extends java.lang.Object is unnecessary
            boolean needObjectClass = argumentStack % 2 != 0 || seenParameter;
            if (needObjectClass) {
                declaration.append(separator).append(name.replace('/', '.'));
            }
        } else {
            declaration.append(separator).append(name.replace('/', '.'));
        }
        separator = "";
        argumentStack *= 2;
    }

    @Override
    public void visitInnerClassType(final String name) {
        if (argumentStack % 2 != 0) {
            declaration.append('>');
        }
        argumentStack /= 2;
        declaration.append('.');
        declaration.append(separator).append(name.replace('/', '.'));
        separator = "";
        argumentStack *= 2;
    }

    @Override
    public void visitTypeArgument() {
        if (argumentStack % 2 == 0) {
            ++argumentStack;
            declaration.append('<');
        } else {
            declaration.append(", ");
        }
        declaration.append('?');
    }

    @Override
    public SignatureVisitor visitTypeArgument(final char tag) {
        if (argumentStack % 2 == 0) {
            ++argumentStack;
            declaration.append('<');
        } else {
            declaration.append(", ");
        }

        if (tag == EXTENDS) {
            declaration.append("? extends ");
        } else if (tag == SUPER) {
            declaration.append("? super ");
        }

        startType();
        return this;
    }

    @Override
    public void visitEnd() {
        if (argumentStack % 2 != 0) {
            declaration.append('>');
        }
        argumentStack /= 2;
        endType();
    }

    public String getDeclaration() {
        return declaration.toString();
    }

    public String getReturnType() {
        return returnType == null ? null : returnType.toString();
    }

    public String getExceptions() {
        return exceptions == null ? null : exceptions.toString();
    }

	public String[] getExceptionsArray() {		 // jodd
		if (exceptions == null) {
			return null;
		}
		String[] result = StringUtil.splitc(exceptions.toString(), ',');

		StringUtil.trimAll(result);

		return result;
	}

    // -----------------------------------------------

    private void endFormals() {
        if (seenFormalParameter) {
            declaration.append('>');
            seenFormalParameter = false;
        }
    }

    private void startType() {
        arrayStack *= 2;
    }

    private void endType() {
        if (arrayStack % 2 == 0) {
            arrayStack /= 2;
        } else {
            while (arrayStack % 2 != 0) {
                arrayStack /= 2;
                declaration.append("[]");
            }
        }
    }
}