BEGIN LICENSE BLOCK *****
Version: EPL 2.0/GPL 2.0/LGPL 2.1
The contents of this file are subject to the Eclipse Public
License Version 2.0 (the "License"); you may not use this file
except in compliance with the License. You may obtain a copy of
the License at http://www.eclipse.org/legal/epl-v20.html
Software distributed under the License is distributed on an "AS
IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
implied. See the License for the specific language governing
rights and limitations under the License.
Copyright (C) 2001 Chad Fowler 
Copyright (C) 2001 Alan Moore 
Copyright (C) 2001-2004 Jan Arne Petersen 
Copyright (C) 2002-2004 Anders Bengtsson 
Copyright (C) 2002-2005 Thomas E Enebo 
Copyright (C) 2004 Stefan Matthias Aust 
Copyright (C) 2005 Charles O Nutter 
Copyright (C) 2007 Miguel Covarrubias 
Alternatively, the contents of this file may be used under the terms of
either of the GNU General Public License Version 2 or later (the "GPL"),
or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
in which case the provisions of the GPL or the LGPL are applicable instead
of those above. If you wish to allow use of your version of this file only
under the terms of either the GPL or the LGPL, and not to allow others to
use your version of this file under the terms of the EPL, indicate your
decision by deleting the provisions above and replace them with the notice
and other provisions required by the GPL or the LGPL. If you do not delete
the provisions above, a recipient may use your version of this file under
the terms of any one of the EPL, the GPL or the LGPL.
END LICENSE BLOCK /***** BEGIN LICENSE BLOCK *****
 * Version: EPL 2.0/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Eclipse Public
 * License Version 2.0 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy of
 * the License at http://www.eclipse.org/legal/epl-v20.html
 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * Copyright (C) 2001 Chad Fowler <chadfowler@chadfowler.com>
 * Copyright (C) 2001 Alan Moore <alan_moore@gmx.net>
 * Copyright (C) 2001-2004 Jan Arne Petersen <jpetersen@uni-bonn.de>
 * Copyright (C) 2002-2004 Anders Bengtsson <ndrsbngtssn@yahoo.se>
 * Copyright (C) 2002-2005 Thomas E Enebo <enebo@acm.org>
 * Copyright (C) 2004 Stefan Matthias Aust <sma@3plus4.de>
 * Copyright (C) 2005 Charles O Nutter <headius@headius.com>
 * Copyright (C) 2007 Miguel Covarrubias <mlcovarrubias@gmail.com>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the EPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the EPL, the GPL or the LGPL.
 ***** END LICENSE BLOCK *****/

package org.jruby;

import org.jruby.anno.JRubyClass;
import org.jruby.anno.JRubyMethod;
import org.jruby.ir.runtime.IRRuntimeHelpers;
import org.jruby.lexer.yacc.ISourcePosition;
import org.jruby.parser.StaticScope;
import org.jruby.runtime.Binding;
import org.jruby.runtime.Block;
import org.jruby.runtime.BlockBody;
import org.jruby.runtime.ClassIndex;
import org.jruby.runtime.Helpers;
import org.jruby.runtime.ObjectAllocator;
import org.jruby.runtime.Signature;
import org.jruby.runtime.ThreadContext;
import org.jruby.runtime.builtin.IRubyObject;
import org.jruby.runtime.marshal.DataType;

import static org.jruby.util.RubyStringBuilder.types;

Author:
 jpetersen/**
 * @author  jpetersen
 */
@JRubyClass(name="Proc")
public class RubyProc extends RubyObject implements DataType {
    private Block block = Block.NULL_BLOCK;
    private Block.Type type;
    private String file = null;
    private int line = -1;

    protected RubyProc(Ruby runtime, RubyClass rubyClass, Block.Type type) {
        super(runtime, rubyClass);

        this.type = type;
    }

    @Deprecated
    protected RubyProc(Ruby runtime, RubyClass rubyClass, Block.Type type, ISourcePosition sourcePosition) {
        this(runtime, rubyClass, type, sourcePosition.getFile(), sourcePosition.getLine());
    }

    protected RubyProc(Ruby runtime, RubyClass rubyClass, Block.Type type, String file, int line) {
        this(runtime, rubyClass, type);

        this.file = file;
        this.line = line;
    }


    public RubyProc(Ruby runtime, RubyClass rubyClass, Block block, String file, int line) {
        this(runtime, rubyClass, block.type, file, line);
        this.block = block;
    }

    public static RubyClass createProcClass(Ruby runtime) {
        RubyClass procClass = runtime.defineClass("Proc", runtime.getObject(), ObjectAllocator.NOT_ALLOCATABLE_ALLOCATOR);
        runtime.setProc(procClass);

        procClass.setClassIndex(ClassIndex.PROC);
        procClass.setReifiedClass(RubyProc.class);

        procClass.defineAnnotatedMethods(RubyProc.class);

        return procClass;
    }

    public Block getBlock() {
        return block;
    }

    // Proc class

    @Deprecated
    public static RubyProc newProc(Ruby runtime, Block.Type type) {
        throw runtime.newRuntimeError("deprecated RubyProc.newProc with no block; do not use");
    }

    public static RubyProc newProc(Ruby runtime, Block block, Block.Type type) {
        RubyProc proc = new RubyProc(runtime, runtime.getProc(), type);
        proc.setup(block);

        return proc;
    }

    @Deprecated
    public static RubyProc newProc(Ruby runtime, Block block, Block.Type type, ISourcePosition sourcePosition) {
        RubyProc proc = new RubyProc(runtime, runtime.getProc(), type, sourcePosition);
        proc.setup(block);

        return proc;
    }

    public static RubyProc newProc(Ruby runtime, Block block, Block.Type type, String file, int line) {
        RubyProc proc = new RubyProc(runtime, runtime.getProc(), type, file, line);
        proc.setup(block);

        return proc;
    }

    
Create a new instance of a Proc object.  We override this method (from RubyClass)
since we need to deal with special case of Proc.new with no arguments or block arg.  In
this case, we need to check previous frame for a block to consume.
/**
     * Create a new instance of a Proc object.  We override this method (from RubyClass)
     * since we need to deal with special case of Proc.new with no arguments or block arg.  In
     * this case, we need to check previous frame for a block to consume.
     */
    @JRubyMethod(name = "new", rest = true, meta = true)
    public static IRubyObject newInstance(ThreadContext context, IRubyObject recv, IRubyObject[] args, Block block) {
        // No passed in block, lets check next outer frame for one ('Proc.new')
        if (!block.isGiven()) block = context.getCurrentFrame().getBlock();

        // This metaclass == recv check seems gross, but MRI seems to do the same:
        // if (!proc && ruby_block->block_obj && CLASS_OF(ruby_block->block_obj) == klass) {
        if (block.isGiven() && block.getProcObject() != null && block.getProcObject().metaClass == recv) {
            return block.getProcObject();
        }

        RubyProc obj = new RubyProc(context.runtime, (RubyClass)recv, Block.Type.PROC);
        obj.setup(block);

        obj.callMethod(context, "initialize", args, block);
        return obj;
    }

    private void setup(Block procBlock) {
        if (!procBlock.isGiven()) {
            throw getRuntime().newArgumentError("tried to create Proc object without a block");
        }

        if (isLambda()) {
            // TODO: warn "tried to create Proc object without a block"
        }

        if (isThread()) {
            // binding for incoming proc must not share frame
            Binding oldBinding = procBlock.getBinding();
            Binding newBinding = new Binding(
                    oldBinding.getSelf(),
                    oldBinding.getFrame().duplicate(),
                    oldBinding.getVisibility(),
                    oldBinding.getDynamicScope(),
                    oldBinding.getMethod(),
                    oldBinding.getFile(),
                    oldBinding.getLine());
            block = new Block(procBlock.getBody(), newBinding);

            // Mark as escaped, so non-local flow errors immediately
            block.escape();

            // modify the block with a new backref/lastline-grabbing scope
            StaticScope oldScope = block.getBody().getStaticScope();
            StaticScope newScope = oldScope.duplicate();
            block.getBody().setStaticScope(newScope);
        } else {
            // just use as is
            block = procBlock;
        }

        // force file/line info into the new block's binding
        block.getBinding().setFile(block.getBody().getFile());
        block.getBinding().setLine(block.getBody().getLine());

        block.type = type;
        block.setProcObject(this);

        // pre-request dummy scope to avoid clone overhead in lightweight blocks
        block.getBinding().getDummyScope(block.getBody().getStaticScope());
    }

    @JRubyMethod(name = "clone")
    @Override
    public IRubyObject rbClone() {
    	RubyProc newProc = newProc(getRuntime(), block, type, file, line);
    	// TODO: CLONE_SETUP here
    	return newProc;
    }

    @JRubyMethod(name = "dup")
    @Override
    public IRubyObject dup() {
        return newProc(getRuntime(), block, type, file, line);
    }

    @Override
    @JRubyMethod(name = "to_s", alias = "inspect")
    public IRubyObject to_s() {
        Ruby runtime = getRuntime();
        RubyString string = runtime.newString("#<");

        string.append(types(runtime, type()));
        string.catString(":0x" + Integer.toString(System.identityHashCode(block), 16));

        String file = block.getBody().getFile();
        if (file != null) string.catString("@" + file + ":" + (block.getBody().getLine() + 1));

        if (isLambda()) string.catString(" (lambda)");
        string.catString(">");

        if (isTaint()) string.setTaint(true);

        return string;
    }

    @JRubyMethod(name = "binding")
    public IRubyObject binding() {
        return getRuntime().newBinding(block.getBinding());
    }

    
For Type.LAMBDA, ensures that the args have the correct arity.
For others, transforms the given arguments appropriately for the given arity (i.e. trimming to one arg for fixed
arity of one, etc.)
/**
     * For Type.LAMBDA, ensures that the args have the correct arity.
     *
     * For others, transforms the given arguments appropriately for the given arity (i.e. trimming to one arg for fixed
     * arity of one, etc.)
     */
    public static IRubyObject[] prepareArgs(ThreadContext context, Block.Type type, BlockBody blockBody, IRubyObject[] args) {
        if (type == Block.Type.LAMBDA) {
            blockBody.getSignature().checkArity(context.runtime, args);
            return args;
        }

        // FIXME: weirdly nearly identical logic exists in prepareBlockArgsInternal but only for lambdas.
        // for procs and blocks, single array passed to multi-arg must be spread
        int arityValue = blockBody.getSignature().arityValue();
        if (args.length == 1 && (arityValue < -1 || arityValue > 1)) args = IRRuntimeHelpers.toAry(context, args);

        return args;
    }

    @JRubyMethod(name = {"call", "[]", "yield", "==="}, rest = true, omit = true)
    public final IRubyObject call(ThreadContext context, IRubyObject[] args, Block blockCallArg) {
        IRubyObject[] preppedArgs = prepareArgs(context, type, block.getBody(), args);

        return call(context, preppedArgs, null, blockCallArg);
    }

    public final IRubyObject call(ThreadContext context, IRubyObject arg) {
        return block.call(context, arg);
    }

    public final IRubyObject call(ThreadContext context, IRubyObject... args) {
        return block.call(context, args);
    }

    public final IRubyObject call(ThreadContext context, IRubyObject[] args, IRubyObject self, Block passedBlock) {
        return call(context, args, self, null, passedBlock);
    }

    public final IRubyObject call(ThreadContext context, IRubyObject[] args, IRubyObject self, RubyModule sourceModule, Block passedBlock) {
        assert args != null;

        Block newBlock;

        // bind to new self and source module, if given
        if (self == null || sourceModule == null) {
            newBlock = block;
        } else {
            newBlock = block.cloneBlockAndFrame();
            if (self != null) {
                newBlock.getBinding().setSelf(self);
            }
            if (sourceModule != null) {
                newBlock.getFrame().setKlazz(sourceModule);
            }
        }

        return newBlock.call(context, args, passedBlock);
    }

    @JRubyMethod(name = "arity")
    public RubyFixnum arity() {
        Signature signature = block.getSignature();

        if (block.type == Block.Type.LAMBDA) return getRuntime().newFixnum(signature.arityValue());

        // FIXME: Consider min/max like MRI here instead of required + kwarg count.
        return getRuntime().newFixnum(signature.hasRest() ? signature.arityValue() : signature.required() + signature.getRequiredKeywordForArityCount());
    }

    @JRubyMethod(name = "to_proc")
    public RubyProc to_proc() {
    	return this;
    }

    @JRubyMethod
    public IRubyObject source_location(ThreadContext context) {
        Ruby runtime = context.runtime;
        if (file != null) {
            return runtime.newArray(runtime.newString(file), runtime.newFixnum(line + 1 /*zero-based*/));
        }

        if (block != null) {
            Binding binding = block.getBinding();

            // block+binding may exist for a core method, which will have a null filename
            if (binding.getFile() != null) {
                return runtime.newArray(
                        runtime.newString(binding.getFile()),
                        runtime.newFixnum(binding.getLine() + 1 /*zero-based*/));
            }
        }

        return context.nil;
    }

    @JRubyMethod
    public IRubyObject parameters(ThreadContext context) {
        BlockBody body = this.getBlock().getBody();

        return Helpers.argumentDescriptorsToParameters(context.runtime,
                body.getArgumentDescriptors(), isLambda());
    }

    @JRubyMethod(name = "lambda?")
    public IRubyObject lambda_p(ThreadContext context) {
        return context.runtime.newBoolean(isLambda());
    }

    private boolean isLambda() {
        return type.equals(Block.Type.LAMBDA);
    }

    //private boolean isProc() {
    //    return type.equals(Block.Type.PROC);
    //}

    private boolean isThread() {
        return type.equals(Block.Type.THREAD);
    }

    @Deprecated
    public final IRubyObject call19(ThreadContext context, IRubyObject[] args, Block block) {
        return call(context, args, block);
    }

    @Deprecated
    public IRubyObject to_s19() {
        return to_s();
    }

}