/*
 * [The "BSD licence"]
 * Copyright (c) 2005-2008 Terence Parr
 * All rights reserved.
 *
 * Conversion to C#:
 * Copyright (c) 2008-2009 Sam Harwell, Pixel Mine, Inc.
 * 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. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */

namespace Antlr.Runtime.Debug {
    using ITreeAdaptor = Antlr.Runtime.Tree.ITreeAdaptor;

    /** <summary>
     *  A TreeAdaptor proxy that fires debugging events to a DebugEventListener
     *  delegate and uses the TreeAdaptor delegate to do the actual work.  All
     *  AST events are triggered by this adaptor; no code gen changes are needed
     *  in generated rules.  Debugging events are triggered *after* invoking
     *  tree adaptor routines.
     *  </summary>
     *
     *  <remarks>
     *  Trees created with actions in rewrite actions like "-&gt; ^(ADD {foo} {bar})"
     *  cannot be tracked as they might not use the adaptor to create foo, bar.
     *  The debug listener has to deal with tree node IDs for which it did
     *  not see a createNode event.  A single &lt;unknown&gt; node is sufficient even
     *  if it represents a whole tree.
     *  </remarks>
     */
    public class DebugTreeAdaptor : ITreeAdaptor {
        protected IDebugEventListener dbg;
        protected ITreeAdaptor adaptor;

        public DebugTreeAdaptor(IDebugEventListener dbg, ITreeAdaptor adaptor) {
            this.dbg = dbg;
            this.adaptor = adaptor;
        }

        public virtual object Create(IToken payload) {
            if (payload.TokenIndex < 0) {
                // could be token conjured up during error recovery
                return Create(payload.Type, payload.Text);
            }
            object node = adaptor.Create(payload);
            dbg.CreateNode(node, payload);
            return node;
        }

        public virtual object ErrorNode(ITokenStream input, IToken start, IToken stop,
                                RecognitionException e) {
            object node = adaptor.ErrorNode(input, start, stop, e);
            if (node != null) {
                dbg.ErrorNode(node);
            }
            return node;
        }

        public virtual object DupTree(object tree) {
            object t = adaptor.DupTree(tree);
            // walk the tree and emit create and add child events
            // to simulate what dupTree has done. dupTree does not call this debug
            // adapter so I must simulate.
            SimulateTreeConstruction(t);
            return t;
        }

        /** <summary>^(A B C): emit create A, create B, add child, ...</summary> */
        protected virtual void SimulateTreeConstruction(object t) {
            dbg.CreateNode(t);
            int n = adaptor.GetChildCount(t);
            for (int i = 0; i < n; i++) {
                object child = adaptor.GetChild(t, i);
                SimulateTreeConstruction(child);
                dbg.AddChild(t, child);
            }
        }

        public virtual object DupNode(object treeNode) {
            object d = adaptor.DupNode(treeNode);
            dbg.CreateNode(d);
            return d;
        }

        public virtual object Nil() {
            object node = adaptor.Nil();
            dbg.NilNode(node);
            return node;
        }

        public virtual bool IsNil(object tree) {
            return adaptor.IsNil(tree);
        }

        public virtual void AddChild(object t, object child) {
            if (t == null || child == null) {
                return;
            }
            adaptor.AddChild(t, child);
            dbg.AddChild(t, child);
        }

        public virtual object BecomeRoot(object newRoot, object oldRoot) {
            object n = adaptor.BecomeRoot(newRoot, oldRoot);
            dbg.BecomeRoot(newRoot, oldRoot);
            return n;
        }

        public virtual object RulePostProcessing(object root) {
            return adaptor.RulePostProcessing(root);
        }

        public virtual void AddChild(object t, IToken child) {
            object n = this.Create(child);
            this.AddChild(t, n);
        }

        public virtual object BecomeRoot(IToken newRoot, object oldRoot) {
            object n = this.Create(newRoot);
            adaptor.BecomeRoot(n, oldRoot);
            dbg.BecomeRoot(newRoot, oldRoot);
            return n;
        }

        public virtual object Create(int tokenType, IToken fromToken) {
            object node = adaptor.Create(tokenType, fromToken);
            dbg.CreateNode(node);
            return node;
        }

        public virtual object Create(int tokenType, IToken fromToken, string text) {
            object node = adaptor.Create(tokenType, fromToken, text);
            dbg.CreateNode(node);
            return node;
        }

        public virtual object Create(int tokenType, string text) {
            object node = adaptor.Create(tokenType, text);
            dbg.CreateNode(node);
            return node;
        }

        public virtual int GetType(object t) {
            return adaptor.GetType(t);
        }

        public virtual void SetType(object t, int type) {
            adaptor.SetType(t, type);
        }

        public virtual string GetText(object t) {
            return adaptor.GetText(t);
        }

        public virtual void SetText(object t, string text) {
            adaptor.SetText(t, text);
        }

        public virtual IToken GetToken(object t) {
            return adaptor.GetToken(t);
        }

        public virtual void SetTokenBoundaries(object t, IToken startToken, IToken stopToken) {
            adaptor.SetTokenBoundaries(t, startToken, stopToken);
            if (t != null && startToken != null && stopToken != null) {
                dbg.SetTokenBoundaries(
                    t, startToken.TokenIndex,
                    stopToken.TokenIndex);
            }
        }

        public virtual int GetTokenStartIndex(object t) {
            return adaptor.GetTokenStartIndex(t);
        }

        public virtual int GetTokenStopIndex(object t) {
            return adaptor.GetTokenStopIndex(t);
        }

        public virtual object GetChild(object t, int i) {
            return adaptor.GetChild(t, i);
        }

        public virtual void SetChild(object t, int i, object child) {
            adaptor.SetChild(t, i, child);
        }

        public virtual object DeleteChild(object t, int i) {
            return DeleteChild(t, i);
        }

        public virtual int GetChildCount(object t) {
            return adaptor.GetChildCount(t);
        }

        public virtual int GetUniqueID(object node) {
            return adaptor.GetUniqueID(node);
        }

        public virtual object GetParent(object t) {
            return adaptor.GetParent(t);
        }

        public virtual int GetChildIndex(object t) {
            return adaptor.GetChildIndex(t);
        }

        public virtual void SetParent(object t, object parent) {
            adaptor.SetParent(t, parent);
        }

        public virtual void SetChildIndex(object t, int index) {
            adaptor.SetChildIndex(t, index);
        }

        public virtual void ReplaceChildren(object parent, int startChildIndex, int stopChildIndex, object t) {
            adaptor.ReplaceChildren(parent, startChildIndex, stopChildIndex, t);
        }

        #region support

        public virtual IDebugEventListener GetDebugListener() {
            return dbg;
        }

        public virtual void SetDebugListener(IDebugEventListener dbg) {
            this.dbg = dbg;
        }

        public virtual ITreeAdaptor GetTreeAdaptor() {
            return adaptor;
        }

        #endregion
    }
}