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1// [The "BSD licence"]
2// Copyright (c) 2010 Alan Condit
3// All rights reserved.
4//
5// Redistribution and use in source and binary forms, with or without
6// modification, are permitted provided that the following conditions
7// are met:
8// 1. Redistributions of source code must retain the above copyright
9//    notice, this list of conditions and the following disclaimer.
10// 2. Redistributions in binary form must reproduce the above copyright
11//    notice, this list of conditions and the following disclaimer in the
12//    documentation and/or other materials provided with the distribution.
13// 3. The name of the author may not be used to endorse or promote products
14//    derived from this software without specific prior written permission.
15//
16// THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17// IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18// OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19// IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21// NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25// THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26
27#import "BaseTreeAdaptor.h"
28#import "RuntimeException.h"
29#import "UniqueIDMap.h"
30#import "MapElement.h"
31#import "CommonTree.h"
32
33@implementation BaseTreeAdaptor
34
35@synthesize treeToUniqueIDMap;
36@synthesize uniqueNodeID;
37
38+ (id<Tree>) newEmptyTree
39{
40    return [[CommonTree alloc] init];
41}
42
43- (id) init
44{
45    self = [super init];
46    if ( self != nil ) {
47    }
48    return self;
49}
50
51- (id) copyWithZone:(NSZone *)aZone
52{
53    BaseTreeAdaptor *copy;
54
55    copy = [[[self class] alloc] init];
56    if (treeToUniqueIDMap)
57        copy.treeToUniqueIDMap = [treeToUniqueIDMap copyWithZone:aZone];
58    copy.uniqueNodeID = uniqueNodeID;
59    return copy;
60}
61
62
63- (id) createNil
64{
65    return [CommonTree newTreeWithToken:nil];
66}
67
68- (id) emptyNode
69{
70    return [CommonTree newTreeWithToken:nil];
71}
72
73/** create tree node that holds the start and stop tokens associated
74 *  with an error.
75 *
76 *  If you specify your own kind of tree nodes, you will likely have to
77 *  override this method. CommonTree returns Token.INVALID_TOKEN_TYPE
78 *  if no token payload but you might have to set token type for diff
79 *  node type.
80 *
81 *  You don't have to subclass CommonErrorNode; you will likely need to
82 *  subclass your own tree node class to avoid class cast exception.
83 */
84- (id) errorNode:(id<TokenStream>)anInput
85            From:(id<Token>)startToken
86              To:(id<Token>)stopToken
87       Exception:(RecognitionException *) e;
88{
89    //System.out.println("returning error node '"+t+"' @index="+anInput.index());
90    return [CommonErrorNode newCommonErrorNode:anInput
91                                                    From:startToken
92                                                      To:stopToken
93                                               Exception:e];
94}
95
96- (BOOL) isNil:(id) tree
97{
98    return [(id)tree isNil];
99}
100
101- (id)dupTree:(id)tree
102{
103    return [self dupTree:(id)tree Parent:nil];
104}
105
106/** This is generic in the sense that it will work with any kind of
107 *  tree (not just Tree interface).  It invokes the adaptor routines
108 *  not the tree node routines to do the construction.
109 */
110- (id)dupTree:(id)t Parent:(id)parent
111{
112    if ( t==nil ) {
113        return nil;
114    }
115    id newTree = [self dupNode:t];
116    // ensure new subtree root has parent/child index set
117    [self setChildIndex:newTree With:[self getChildIndex:t]]; // same index in new tree
118    [self setParent:newTree With:parent];
119    NSInteger n = [self getChildCount:t];
120    for (NSInteger i = 0; i < n; i++) {
121        id child = [self getChild:t At:i];
122        id newSubTree = [self dupTree:child Parent:t];
123        [self addChild:newSubTree toTree:newTree];
124    }
125    return newTree;
126}
127
128- (id)dupNode:(id)aNode
129{
130    return aNode; // override for better results :>)
131}
132/** Add a child to the tree t.  If child is a flat tree (a list), make all
133 *  in list children of t.  Warning: if t has no children, but child does
134 *  and child isNil then you can decide it is ok to move children to t via
135 *  t.children = child.children; i.e., without copying the array.  Just
136 *  make sure that this is consistent with have the user will build
137 *  ASTs.
138 */
139- (void) addChild:(id)child toTree:(id)t
140{
141    if ( t != nil && child != nil ) {
142        [(id)t addChild:child];
143    }
144}
145
146/** If oldRoot is a nil root, just copy or move the children to newRoot.
147 *  If not a nil root, make oldRoot a child of newRoot.
148 *
149 *    old=^(nil a b c), new=r yields ^(r a b c)
150 *    old=^(a b c), new=r yields ^(r ^(a b c))
151 *
152 *  If newRoot is a nil-rooted single child tree, use the single
153 *  child as the new root node.
154 *
155 *    old=^(nil a b c), new=^(nil r) yields ^(r a b c)
156 *    old=^(a b c), new=^(nil r) yields ^(r ^(a b c))
157 *
158 *  If oldRoot was null, it's ok, just return newRoot (even if isNil).
159 *
160 *    old=null, new=r yields r
161 *    old=null, new=^(nil r) yields ^(nil r)
162 *
163 *  Return newRoot.  Throw an exception if newRoot is not a
164 *  simple node or nil root with a single child node--it must be a root
165 *  node.  If newRoot is ^(nil x) return x as newRoot.
166 *
167 *  Be advised that it's ok for newRoot to point at oldRoot's
168 *  children; i.e., you don't have to copy the list.  We are
169 *  constructing these nodes so we should have this control for
170 *  efficiency.
171 */
172- (id)becomeRoot:(id)newRoot old:(id)oldRoot
173{
174    if ( oldRoot == nil ) {
175        return newRoot;
176    }
177    //System.out.println("becomeroot new "+newRoot.toString()+" old "+oldRoot);
178    id newRootTree = (id)newRoot;
179    id oldRootTree = (id)oldRoot;
180    // handle ^(nil real-node)
181    if ( [newRootTree isNil] ) {
182        NSInteger nc = [newRootTree getChildCount];
183        if ( nc == 1 ) newRootTree = [(id)newRootTree getChild:0];
184        else if ( nc > 1 ) {
185            // TODO: make tree run time exceptions hierarchy
186            @throw [RuntimeException newException:NSStringFromClass([self class]) reason:@"more than one node as root (TODO: make exception hierarchy)"];
187        }
188    }
189    // add oldRoot to newRoot; addChild takes care of case where oldRoot
190    // is a flat list (i.e., nil-rooted tree).  All children of oldRoot
191    // are added to newRoot.
192    [newRootTree addChild:oldRootTree];
193    return newRootTree;
194}
195
196/** Transform ^(nil x) to x and nil to null */
197- (id)rulePostProcessing:(id)root
198{
199    //System.out.println("rulePostProcessing: "+((Tree)root).toStringTree());
200    id r = (id)root;
201    if ( r != nil && [r isNil] ) {
202        if ( [r getChildCount] == 0 ) {
203            r = nil;
204        }
205        else if ( [r getChildCount] == 1 ) {
206            r = (id)[r getChild:0];
207            // whoever invokes rule will set parent and child index
208            [r setParent:nil];
209            [r setChildIndex:-1];
210        }
211    }
212    return r;
213}
214
215- (id)becomeRootfromToken:(id<Token>)newRoot old:(id)oldRoot
216{
217    return [self becomeRoot:(id)[self create:newRoot] old:oldRoot];
218}
219
220- (id) create:(id<Token>)aToken
221{
222    return [CommonTree newTreeWithToken:aToken];
223}
224
225- (id)createTree:(NSInteger)tokenType FromToken:(id<Token>)fromToken
226{
227    fromToken = [self createToken:fromToken];
228    //((ClassicToken)fromToken).setType(tokenType);
229    [fromToken setType:tokenType];
230    id t = [self create:fromToken];
231    return t;
232}
233
234- (id)createTree:(NSInteger)tokenType FromToken:(id<Token>)fromToken Text:(NSString *)text
235{
236    if (fromToken == nil)
237        return [self createTree:tokenType Text:text];
238    fromToken = [self createToken:fromToken];
239    [fromToken setType:tokenType];
240    [fromToken setText:text];
241    id t = [self create:fromToken];
242    return t;
243}
244
245- (id)createTree:(NSInteger)tokenType Text:(NSString *)text
246{
247    id<Token> fromToken = [self createToken:tokenType Text:text];
248    id t = (id)[self create:fromToken];
249    return t;
250}
251
252- (NSInteger) getType:(CommonTree *) t
253{
254    return [t type];
255}
256
257- (void) setType:(id)t Type:(NSInteger)type
258{
259    @throw [NoSuchElementException newException:@"don't know enough about Tree node"];
260}
261
262/** What is the Token associated with this node?  If
263 *  you are not using CommonTree, then you must
264 *  override this in your own adaptor.
265 */
266- (id<Token>) getToken:(CommonTree *) t
267{
268    if ( [t isKindOfClass:[CommonTree class]] ) {
269        return [t getToken];
270    }
271    return nil; // no idea what to do
272}
273
274- (NSString *)getText:(CommonTree *)t
275{
276    return [t text];
277}
278
279- (void) setText:(id)t Text:(NSString *)text
280{
281    @throw [NoSuchElementException newException:@"don't know enough about Tree node"];
282}
283
284- (id) getChild:(id)t At:(NSInteger)index
285{
286    return [(id)t getChild:index ];
287}
288
289- (void) setChild:(id)t At:(NSInteger)index Child:(id)child
290{
291    [(id)t setChild:index With:(id)child];
292}
293
294- (id) deleteChild:(id)t Index:(NSInteger)index
295{
296    return [(id)t deleteChild:index];
297}
298
299- (NSInteger) getChildCount:(id)t
300{
301    return [(id)t getChildCount];
302}
303
304- (id<BaseTree>) getParent:(id<BaseTree>) t
305{
306    if ( t == nil )
307        return nil;
308    return (id<BaseTree>)[t getParent];
309}
310
311- (void) setParent:(id<BaseTree>)t With:(id<BaseTree>) parent
312{
313    if ( t != nil )
314        [(id<BaseTree>) t setParent:(id<BaseTree>)parent];
315}
316
317/** What index is this node in the child list? Range: 0..n-1
318 *  If your node type doesn't handle this, it's ok but the tree rewrites
319 *  in tree parsers need this functionality.
320 */
321- (NSInteger) getChildIndex:(id)t
322{
323    return ((CommonTree *)t).childIndex;
324}
325
326- (void) setChildIndex:(id)t With:(NSInteger)index
327{
328    ((CommonTree *)t).childIndex = index;
329}
330
331- (void) replaceChildren:(id)parent From:(NSInteger)startChildIndex To:(NSInteger)stopChildIndex With:(id)t
332{
333    return;
334}
335
336- (NSInteger) getUniqueID:(id)node
337{
338    if ( treeToUniqueIDMap == nil ) {
339        treeToUniqueIDMap = [UniqueIDMap newUniqueIDMap];
340    }
341    ACNumber *prevID = [treeToUniqueIDMap getNode:node];
342    if ( prevID != nil ) {
343        return [prevID integerValue];
344    }
345    NSInteger anID = uniqueNodeID;
346    // MapElement *aMapNode = [MapElement newMapElementWithObj1:[ACNumber numberWithInteger:anID] Obj2:node];
347    [treeToUniqueIDMap putID:[ACNumber numberWithInteger:anID] Node:node];
348    uniqueNodeID++;
349    return anID;
350    // GCC makes these nonunique:
351    // return System.identityHashCode(node);
352}
353
354/** Tell me how to create a token for use with imaginary token nodes.
355 *  For example, there is probably no input symbol associated with imaginary
356 *  token DECL, but you need to create it as a payload or whatever for
357 *  the DECL node as in ^(DECL type ID).
358 *
359 *  If you care what the token payload objects' type is, you should
360 *  override this method and any other createToken variant.
361 */
362- (id<Token>) createToken:(NSInteger)aTType Text:(NSString *)text
363{
364    return nil;
365}
366
367/** Tell me how to create a token for use with imaginary token nodes.
368 *  For example, there is probably no input symbol associated with imaginary
369 *  token DECL, but you need to create it as a payload or whatever for
370 *  the DECL node as in ^(DECL type ID).
371 *
372 *  This is a variant of createToken where the new token is derived from
373 *  an actual real input token.  Typically this is for converting '{'
374 *  tokens to BLOCK etc...  You'll see
375 *
376 *    r : lc='{' ID+ '}' -> ^(BLOCK[$lc] ID+) ;
377 *
378 *  If you care what the token payload objects' type is, you should
379 *  override this method and any other createToken variant.
380 */
381- (id<Token>) createToken:(id<Token>) fromToken
382{
383    return nil;
384}
385
386/** Track start/stop token for subtree root created for a rule.
387 *  Only works with Tree nodes.  For rules that match nothing,
388 *  seems like this will yield start=i and stop=i-1 in a nil node.
389 *  Might be useful info so I'll not force to be i..i.
390 */
391- (void) setTokenBoundaries:(id)aTree From:(id<Token>)startToken To:(id<Token>)stopToken
392{
393    return;
394}
395
396- (NSInteger) getTokenStartIndex:(id)aTree
397{
398    return -1;
399}
400
401- (NSInteger) getTokenStopIndex:(id)aTree
402{
403    return -1;
404}
405
406#ifdef DONTUSENOMO
407- (NSInteger)getUniqueID
408{
409    return uniqueNodeID;
410}
411
412- (void) setUniqueNodeID:(NSInteger)aUniqueNodeID
413{
414    uniqueNodeID = aUniqueNodeID;
415}
416
417- (UniqueIDMap *)getTreeToUniqueIDMap
418{
419    return treeToUniqueIDMap;
420}
421
422- (void) setTreeToUniqueIDMap:(UniqueIDMap *)aMapListNode
423{
424    treeToUniqueIDMap = aMapListNode;
425}
426
427#endif
428
429@end
430