/*
  Copyright (C) 2000-2005 SKYRIX Software AG

  This file is part of SOPE.

  SOPE is free software; you can redistribute it and/or modify it under
  the terms of the GNU Lesser General Public License as published by the
  Free Software Foundation; either version 2, or (at your option) any
  later version.

  SOPE is distributed in the hope that it will be useful, but WITHOUT ANY
  WARRANTY; without even the implied warranty of MERCHANTABILITY or
  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
  License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with SOPE; see the file COPYING.  If not, write to the
  Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  02111-1307, USA.
*/

#include "WOKeyPathAssociation.h"
#include <NGObjWeb/WOComponent.h>
#include "NSObject+WO.h"
#include "common.h"

#if LIB_FOUNDATION_BOEHM_GC
#  if LIB_FOUNDATION_LIBRARY
#    include <extensions/GarbageCollector.h>
#  else
#    error no BoehmGC support on this Foundation!
#  endif
#endif

#if NeXT_RUNTIME || APPLE_RUNTIME
#  include <objc/objc.h>
#  include <objc/objc-api.h>
#  include <objc/objc-class.h>

#  define METHOD_NULL NULL
#  define object_is_instance(XXX) \
     ((XXX != nil) && CLS_ISCLASS(*((Class *)XXX)))
#  define sel_get_uid               sel_getUid
#  define class_get_class_method    class_getClassMethod
#  define class_get_instance_method class_getInstanceMethod

#  define __CLS_INFO(cls)         ((cls)->info)
#  ifndef __CLS_ISINFO
#    define __CLS_ISINFO(cls, mask) ((__CLS_INFO(cls) & mask) == mask)
#  endif
#  ifndef CLS_ISCLASS
#    define CLS_ISCLASS(cls) ((cls) && __CLS_ISINFO(cls, CLS_CLASS))
#  endif
#endif

#if NeXT_Foundation_LIBRARY || COCOA_Foundation_LIBRARY || \
    APPLE_FOUNDATION_LIBRARY
bool _CFDictionaryIsMutable(CFDictionaryRef dict);
#endif


/*
  WOKeyPathAssociation

  This is an association class for so called keypaths. It uses extensive 
  caching to reuse calculated method pointers.

  Note the -kvcIsPreferredInKeyPath method. It is used whether -valueForKey: 
  and -takeValue:forKey: has preference or the objects methods. In usual cases
  it can be assumed that -valueForKey has the preference, but not in the case 
  of

    WOSession, WOComponent, WOApplication, WOContext

  which use -valueForKey: as a fallback. Since -valueForKey: is defined as a
  category on NSObject it eliminates the caching scheme used.
*/

#if DEBUG
// #define HEAVY_DEBUG 1
// #define USE_EXCEPTION_HANDLERS 1
#endif

#if USE_EXCEPTION_HANDLERS
#  warning using local exception handlers in associations, slows down templates
#endif

typedef enum {
  WOKeyType_unknown = 0,
  WOKeyType_kvc     = 1,
  WOKeyType_method  = 2,
  WOKeyType_ivar    = 3,
  WOKeyType_binding = 4
} WOKeyType;

typedef union {
  void           *ivar;
  IMP            method; // real method or takeValue:ForKey:
  char           (*cmethod) (id, SEL);
  unsigned char  (*ucmethod)(id, SEL);
  int            (*imethod) (id, SEL);
  unsigned int   (*uimethod)(id, SEL);
  short          (*smethod) (id, SEL);
  unsigned short (*usmethod)(id, SEL);
  const char *   (*strmethod)(id, SEL);
  float          (*fmethod)(id, SEL);
  double         (*dmethod)(id, SEL);
} WOGetMethodType;

typedef union {
  IMP  method; // real method or takeValue:ForKey:
  void (*omethod)  (id, SEL, id);
  void (*cmethod)  (id, SEL, char);
  void (*ucmethod) (id, SEL, unsigned char);
  void (*imethod)  (id, SEL, int);
  void (*uimethod) (id, SEL, unsigned int);
  void (*smethod)  (id, SEL, short);
  void (*usmethod) (id, SEL, unsigned short);
  void (*strmethod)(id, SEL, const char *);
  void (*fmethod)  (id, SEL, float);
  void (*dmethod)  (id, SEL, double);
} WOSetMethodType;

typedef struct {
  unsigned char   *ckey;
  short           keyLen:12;
  short           isFault:1;
  WOKeyType       type:3;
  id              object;
  Class           isa;
  WOGetMethodType access;
  union {
    NSString *key; // for valueForKey:
    struct {
      SEL get; // get method selector
    } sel;
  } extra;
  unsigned char retType;
} WOKeyPathComponent;

typedef union {
  id             object;
  const char     *cstr;
  int            sint;
  unsigned int   uint;
  short          ss;
  unsigned short us;
  unsigned char  c;
  float          flt;
  double         dbl;
} WOReturnValueHolder;

#define intNumObj(__VAL__) \
  (__VAL__==0?inum0:(__VAL__==1?inum1:[NumberClass numberWithInt:__VAL__]))

#define uintNumObj(__VAL__) \
  (__VAL__ ==0 ? uinum0 : \
  (__VAL__==1?uinum1:[NumberClass numberWithUnsignedInt:__VAL__]))

@implementation WOKeyPathAssociation

+ (int)version {
  return 2;
}

static Class NumberClass = Nil;
static Class StringClass = Nil;
#if NeXT_Foundation_LIBRARY || COCOA_Foundation_LIBRARY || \
    APPLE_FOUNDATION_LIBRARY
static Class NSCFDictionaryClass = Nil;
#endif
static int debugOn = -1;

#define IS_NUMSTR(__VAL__)  (__VAL__>=0 && __VAL__<50)
#define IS_UNUMSTR(__VAL__) (__VAL__<50)
static NSString *numStrings[] = {
  @"0", @"1", @"2", @"3", @"4", @"5", @"6", @"7", @"8", @"9",
  @"10", @"11", @"12", @"13", @"14", @"15", @"16", @"17", @"18", @"19",
  @"20", @"21", @"22", @"23", @"24", @"25", @"26", @"27", @"28", @"29",
  @"30", @"31", @"32", @"33", @"34", @"35", @"36", @"37", @"38", @"39",
  @"40", @"41", @"42", @"43", @"44", @"45", @"46", @"47", @"48", @"49"
};
static NSNumber *inum0  = nil, *inum1  = nil;
static NSNumber *uinum0 = nil, *uinum1 = nil;

+ (void)initialize {
  static BOOL isInitialized = NO;

  if (isInitialized) return;
  isInitialized = YES;
  NSAssert2([super version] == 2,
            @"invalid superclass (%@) version %i !",
            NSStringFromClass([self superclass]), [super version]);

  
  debugOn = [[[NSUserDefaults standardUserDefaults]
                              objectForKey:@"WODebugKeyPathAssociation"]
                              boolValue] ? 1 : 0;
  
  NumberClass = [NSNumber class];
  StringClass = [NSString class];
#if NeXT_Foundation_LIBRARY || COCOA_Foundation_LIBRARY || \
    APPLE_FOUNDATION_LIBRARY
  NSCFDictionaryClass = NSClassFromString(@"NSCFDictionary");
#endif

  inum0  = [[NumberClass numberWithInt:0] retain];
  inum1  = [[NumberClass numberWithInt:1] retain];
  uinum0 = [[NumberClass numberWithUnsignedInt:0] retain];
  uinum1 = [[NumberClass numberWithUnsignedInt:1] retain];
}

static inline WOKeyPathComponent *
_getComponent(register WOKeyPathAssociation *self, register unsigned _idx)
{
  return (WOKeyPathComponent *)
    (self->keyPath + (_idx * sizeof(WOKeyPathComponent)));
}

static inline void _freeKeyPathComponent(WOKeyPathComponent *info) {
  if (info->ckey) {
    free(info->ckey);
    info->ckey = NULL;
  }
  if ((info->type == WOKeyType_kvc) || (info->type == WOKeyType_binding)) {
    [info->extra.key release];
    info->extra.key = nil;
  }
  info->object = nil;
  info->isa    = Nil;
}

static inline void
_parseKeyPath(WOKeyPathAssociation *self,NSString *_keyPath)
{
  unsigned keyLen = [_keyPath cStringLength];
  char *buf;
  char *cstr;
  char *tmp;

  buf = malloc(keyLen + 1);
  cstr = buf;
  tmp = (char *)cstr;
  [_keyPath getCString:buf]; buf[keyLen] = '\0';
  
  // get number of components
  self->size = 1;
  while (*tmp) {
    if (*tmp == '.') (self->size)++;
    tmp++;
  }
  
  self->keyPath = calloc(self->size, sizeof(WOKeyPathComponent));
  
  // transfer components
  {
    unsigned char pos;

    tmp = (char *)cstr;
    for (pos = 0; pos < self->size; pos++) {
      WOKeyPathComponent *info = _getComponent(self, pos);
      
      // goto end or next '.'
      while ((*tmp != '\0') && (*tmp != '.'))
        tmp++;
      
      info->keyLen = (tmp - cstr);
      info->ckey   = malloc(info->keyLen + 4);
      memcpy(info->ckey, cstr, info->keyLen);
      info->ckey[info->keyLen] = '\0';

      NSCAssert(strlen((char *)info->ckey) > 0, @"invalid ckey ..");
      NSCAssert((int)strlen((char *)info->ckey) == (int)info->keyLen, 
                @"size and content differ");
      
      info->object = nil;
      info->isa    = Nil;
      info->type   = WOKeyType_unknown;
      
      cstr = tmp + 1;
      tmp  = (char *)cstr;
    }
  }
  free(buf);
}
  
- (id)initWithKeyPath:(NSString *)_keyPath {
  if ([_keyPath length] < 1) {
    self = [self autorelease];
    self = nil;
    [self errorWithFormat:
            @"passed invalid keypath (%@) to association !", _keyPath];
    return nil;
  }
  if ((self = [super init])) {
    _parseKeyPath(self, _keyPath);
  }
  return self;
}
- (id)init {
  NSLog(@"keypaths can not be created using 'init' ..");
  [NSException raise:@"InvalidUseOfMethodException"
               format:@"keypaths can not be created using 'init'"];
  return nil;
}

- (void)dealloc {
  if (self->keyPath) {
    int cnt;
    
    for (cnt = 0; cnt < self->size; cnt++)
      _freeKeyPathComponent(_getComponent(self, cnt));
    
    free(self->keyPath);
  }
  [super dealloc];
}

/* accessors */

- (NSString *)keyPath {
  register unsigned char pos;
  char     *buffer;
  unsigned len;

  // get size
  len = self->size; // size-1 '.' chars and the '\0' char
  for (pos = 0; pos < self->size; pos++) {
    WOKeyPathComponent *info = _getComponent(self, pos);
    len += info->keyLen;
  }
  buffer = malloc(len + 4);
  
  // transfer contents
  for (pos = 0, len = 0; pos < self->size; pos++) {
    WOKeyPathComponent *info = _getComponent(self, pos);

    if (pos != 0) {
      buffer[len] = '.';
      len++;
    }
    memcpy(&(buffer[len]), info->ckey, info->keyLen);
    len += info->keyLen;
  }
  buffer[len] = '\0';

  return [[[StringClass alloc] initWithCStringNoCopy:buffer
			       length:len
			       freeWhenDone:YES]
	                       autorelease];
}
- (id)initWithString:(NSString *)_s {
  return [self initWithKeyPath:_s];
}

/* value */

static inline void _fillInfo(WOKeyPathAssociation *self, id object,
                             WOKeyPathComponent *info) 
{
  Class clazz      = [object class];
  BOOL  needRefill = NO;
  
  if (info->isFault)
    needRefill = YES;
  else if (info->type == WOKeyType_unknown) // first invocation of 'value'
    needRefill = YES;
  else if ((info->object == nil) || (object == nil))
    needRefill = YES;
  else if (info->isa != clazz)
    needRefill = YES;
  else if (info->object != object)
    needRefill = YES;
  
  if (!needRefill)
    // object is the same, can use cached representation
    return;

  {
#if NeXT_RUNTIME
    struct objc_method *method = NULL;
#else
    Method_t method = METHOD_NULL;
#endif
    
    if ((info->type == WOKeyType_kvc) || (info->type == WOKeyType_binding)) {
      /* release old key */
      [info->extra.key release];
      info->extra.key = nil;
    }
    
    info->type    = WOKeyType_unknown;
    info->retType = _C_ID;
    
    if (*(info->ckey) == '^') { /* a binding key */
      method = class_get_instance_method(clazz, @selector(valueForBinding:));
      info->type = WOKeyType_binding;
      info->extra.key =
        [[StringClass alloc] initWithCString:(char *)(info->ckey + 1)];
    }
    else {
      if (object) {
        if (object_is_instance(object)) {
          if ([object kvcIsPreferredInKeyPath]) {
            method = class_get_instance_method(clazz, @selector(valueForKey:));
            
            if (method != METHOD_NULL) {
              info->type      = WOKeyType_kvc;
              info->extra.key = 
		[[StringClass alloc] initWithCString:(char *)info->ckey];
            }
            else {
              info->extra.sel.get = sel_get_uid((char *)info->ckey);
              method = class_get_instance_method(clazz, info->extra.sel.get);
              if (method != METHOD_NULL)
                info->type = WOKeyType_method;
            }
          }
          else {
            info->extra.sel.get = sel_get_uid((char *)info->ckey);
            method = class_get_instance_method(clazz, info->extra.sel.get);
            
            if (method != METHOD_NULL)
              info->type = WOKeyType_method;
            else {
              method =
                class_get_instance_method(clazz, @selector(valueForKey:));
              if (method != METHOD_NULL) {
                info->type      = WOKeyType_kvc;
                info->extra.key = 
		  [[StringClass alloc] initWithCString:(char *)info->ckey];
              }
            }
          }
        }
        else { /* object is a class */
          method = class_get_class_method(object, @selector(valueForKey:));
          if (method != METHOD_NULL) {
            info->type      = WOKeyType_kvc;
            info->extra.key = 
	      [[StringClass alloc] initWithCString:(char *)info->ckey];
          }
          else {
            info->extra.sel.get = sel_get_uid((char *)info->ckey);
            method =
              class_get_class_method(*(Class *)object, info->extra.sel.get);
            if (method != METHOD_NULL) {
              info->type = WOKeyType_method;
            }
          }
        }
      }
    }
    info->object  = object;
    info->isa     = [object class];
    info->isFault = [object isFault];
    
    if (method != METHOD_NULL) {
#if NeXT_RUNTIME
      info->access.method = method->method_imp;
#else
      info->access.method = method_get_imp(method);
#endif
      info->retType = *(method->method_types);
    }

#if HEAVY_DEBUG
    NSLog(@"type is %i, key is '%s'", info->type, info->ckey);
#endif
  }
}

- (NSException *)handleGetException:(NSException *)_exception  {
  static NSString *excKey    = @"exception";
  static NSString *kpKey     = @"keyPath";
  static NSString *assocKey  = @"association";
  static NSString *excName   = @"WOKeyPathException";
  static NSString *excReason = @"couldn't get value for a keypath component";
  NSException  *e;
  NSDictionary *ui;
  
  ui = [NSDictionary dictionaryWithObjectsAndKeys:
                       _exception,     excKey,
                       [self keyPath], kpKey,
                       self,           assocKey,
                     nil];
  
  e = [[NSException alloc] initWithName:excName
                           reason:excReason
                           userInfo:ui];
  return e;
}

static WOReturnValueHolder _getComponentValue(WOKeyPathAssociation *self,
                                              id object,
                                              WOKeyPathComponent *info)
{
  WOReturnValueHolder retValue;
  
#if DEBUG
  NSCAssert1(info, @"%s: missing info !", __PRETTY_FUNCTION__);
#endif
  
  _fillInfo(self, object, info);
  
  // execute
  if (info->type == WOKeyType_method) {
#if HEAVY_DEBUG
    NSLog(@"get key %s of keyPath %@\n"
	  @"  from: 0x%08X[%@]\n"
	  @"  via method (ret %c)", 
	  info->ckey, [self keyPath], object, 
	  NSStringFromClass([object class]), info->retType);
#endif
#if USE_EXCEPTION_HANDLERS
    NS_DURING {
#endif
      if ((info->retType == _C_ID) || (info->retType == _C_CLASS)) {
        retValue.object = info->access.method(object, info->extra.sel.get);
#if HEAVY_DEBUG
	NSLog(@"  got result 0x%08X[%@]: %@", retValue.object,
	      NSStringFromClass([retValue.object class]),
	      retValue.object);
#endif
      }
      else {
        switch (info->retType) {
          case _C_ID:
          case _C_CLASS:
            retValue.object = info->access.method(object, info->extra.sel.get);
            break;
          case _C_VOID:
            retValue.object = object;
            break;
            
          case _C_CHR:
          case _C_UCHR:
            retValue.c = info->access.ucmethod(object, info->extra.sel.get);
            break;
          
          case _C_INT:
            retValue.sint = info->access.imethod(object, info->extra.sel.get);
            break;
          case _C_UINT:
            retValue.uint = info->access.uimethod(object, info->extra.sel.get);
            break;

          case _C_SHT:
            retValue.ss = info->access.smethod(object, info->extra.sel.get);
            break;
          case _C_USHT:
            retValue.us = info->access.usmethod(object, info->extra.sel.get);
            break;

          case _C_FLT:
            retValue.flt = info->access.fmethod(object, info->extra.sel.get);
            break;
        
          case _C_DBL:
            retValue.dbl = info->access.dmethod(object, info->extra.sel.get);
            break;

          case _C_CHARPTR:
            retValue.cstr = info->access.strmethod(object, info->extra.sel.get);
            break;

          default:
            NSLog(@"%@: unsupported type '%c' !", self, info->retType);
            [NSException raise:@"WORuntimeException"
                         format:
                         @"in WOKeyPathAssociation %@: unsupported type '%c'",
                         self, info->retType];
            break;
        }
      }
#if USE_EXCEPTION_HANDLERS
    }
    NS_HANDLER
      [[self handleGetException:localException] raise];
    NS_ENDHANDLER;
#endif
  }
  else if (info->type == WOKeyType_kvc) {
#if HEAVY_DEBUG
    NSLog(@"get keyPath %@ from %@ via KVC", [self keyPath], object);
#endif
#if 0
    NSLog(@"ckey:      %s", info->ckey);
    NSLog(@"key-class: %s", (*(Class *)info->extra.key)->name);
    NSLog(@"key:       %@", info->extra.key);
#endif

#if LIB_FOUNDATION_BOEHM_GC
    [GarbageCollector collectGarbages];
#endif
    
    retValue.object =
      info->access.method(object, @selector(valueForKey:), info->extra.key);
  }
  else if (info->type == WOKeyType_binding) {
#if HEAVY_DEBUG
    NSLog(@"get keyPath %@ from %@ via binding", [self keyPath], object);
#endif
    
    retValue.object =
      info->access.method(object, @selector(valueForBinding:), info->extra.key);
  }
  else { // unknown || ivar
#if HEAVY_DEBUG
    NSLog(@"unknown info type for keyPath %@ from %@ !!",
          [self keyPath], object);
#endif
    retValue.object = nil;
  }

  return retValue;
}

static inline id _objectify(unsigned char _type, WOReturnValueHolder *_value) {
  id result = nil;

  //NSLog(@"shall convert value of type '%c'", _type);
  
  switch (_type) {
    case _C_ID:
    case _C_CLASS:
      result = _value->object;
      break;
      
    case _C_VOID:
      result = _value->object;
      break;
      
    case _C_CHR:
    case _C_UCHR:
      result = [NumberClass numberWithUnsignedChar:_value->c];
      break;
      
    case _C_INT:
      result = intNumObj(_value->sint);
      break;
    case _C_UINT:
      result = uintNumObj(_value->uint);
      break;
    case _C_SHT:
      result = [NumberClass numberWithShort:_value->ss];
      break;
    case _C_USHT:
      result = [NumberClass numberWithUnsignedShort:_value->us];
      break;
    case _C_FLT:
      result = [NumberClass numberWithFloat:_value->flt];
      break;
    case _C_DBL:
      result = [NumberClass numberWithDouble:_value->dbl];
      break;

    case _C_CHARPTR:
      result = _value->cstr
        ? [StringClass stringWithCString:_value->cstr]
        : nil;
      break;
            
    default:
      NSLog(@"unsupported type '%c' !", _type);
      [NSException raise:@"WORuntimeException"
                   format:@"in WOKeyPathAssociation: unsupported type '%c'",
                     _type];
      break;
  }

  //NSLog(@"made %@[0x%08X].", NSStringFromClass([result class]), result);
  
  return result;
}

static inline id
_getValueN(WOKeyPathAssociation *self, unsigned _count, id root)
{
  register unsigned cnt;
  id object = root;

  for (cnt = 0; (cnt < _count) && (object != nil); cnt++) {
    WOKeyPathComponent  *info;
    WOReturnValueHolder retValue;
    
    info     = _getComponent(self, cnt);
#if DEBUG
    NSCAssert1(info, @"%s: missing info !", __PRETTY_FUNCTION__);
#endif
    retValue = _getComponentValue(self, object, info);
    
    object = (info->type == WOKeyType_method)
      ? _objectify(info->retType, &retValue)
      : retValue.object;
  }

  //NSLog(@"object %@ for keyPath %@", object, [self keyPath]);

  return object;
}

static inline id _getValue(WOKeyPathAssociation *self, id root) {
  return _getValueN(self, self->size, root);
}

static id _getOneValue(WOKeyPathAssociation *self, id root) {
  WOKeyPathComponent  *info;
  WOReturnValueHolder retValue;

  info     = (WOKeyPathComponent *)self->keyPath;
  retValue = _getComponentValue(self, root, info);
  
  return (info->type == WOKeyType_method)
    ? _objectify(info->retType, &retValue)
    : retValue.object;
}

static inline void _getSetSelName(register unsigned char *buf,
                                  register const unsigned char *_key,
                                  register unsigned _len) {
  buf[0] = 's';
  buf[1] = 'e';
  buf[2] = 't';

  switch (_len) {
    case 0: break;

    case 1:
      buf[3] = _key[0];
      break;
    case 2:
      buf[3] = _key[0]; buf[4] = _key[1];
      break;
    case 3:
      buf[3] = _key[0]; buf[4] = _key[1]; buf[5] = _key[2];
      break;
    case 4:
      buf[3] = _key[0]; buf[4] = _key[1]; buf[5] = _key[2];
      buf[6] = _key[3]; break;
    case 5:
      buf[3] = _key[0]; buf[4] = _key[1]; buf[5] = _key[2];
      buf[6] = _key[3]; buf[7] = _key[4];
      break;
    case 6:
      buf[3] = _key[0]; buf[4] = _key[1]; buf[5] = _key[2];
      buf[6] = _key[3]; buf[7] = _key[4]; buf[8] = _key[5];
      break;
      
    default:
      memcpy(&(buf[3]), _key, _len);
      break;
  }
  buf[3] = toupper(buf[3]);
  buf[_len + 3] = ':';
  buf[_len + 4] = '\0';
}
static inline SEL _getSetSel(register const unsigned char *_key,
                             register unsigned _len) {
  unsigned char buf[259];
  _getSetSelName(buf, _key, _len);
  return sel_get_uid((char *)buf);
}

static BOOL _setValue(WOKeyPathAssociation *self, id _value, id root) {
  WOKeyPathComponent *info;
  id object = root;
  
  if (self->size > 1)
    object = _getValueN(self, self->size - 1, root);

  if (object == nil) // nothing to set ..
    return YES; // receiver == nil isn't an error condition

  info = _getComponent(self, self->size - 1);
  NSCAssert(info->keyLen < 255, @"keysize to big ..");

  _fillInfo(self, object, info);
  
  if (info->type == WOKeyType_method) { // determine set-selector
    SEL setSel = _getSetSel(info->ckey, info->keyLen);
      
    if (![object respondsToSelector:setSel]) {
#if 0
      NSLog(@"%@: Could not set value for key '%s', "
            @"object %@ doesn't respond to %@.",
            self, info->ckey, object,
            setSel ? NSStringFromSelector(setSel) : @"<NULL>");
#endif
      return NO;
    }
    else {
      WOSetMethodType sm;

      if ((sm.method = [object methodForSelector:setSel])) {
        switch (info->retType) {
          case _C_CLASS:
          case _C_ID:
            sm.omethod(object, setSel, _value);
            break;

          case _C_CHR:
            sm.cmethod(object, setSel, [_value charValue]);
            break;
          case _C_UCHR:
            sm.ucmethod(object, setSel, [_value unsignedCharValue]);
            break;

          case _C_SHT:
            sm.smethod(object, setSel, [_value shortValue]);
            break;
          case _C_USHT:
            sm.usmethod(object, setSel, [_value unsignedShortValue]);
            break;
            
          case _C_INT:
            sm.imethod(object, setSel, [_value intValue]);
            break;
          case _C_UINT:
            sm.uimethod(object, setSel, [_value unsignedIntValue]);
            break;

          case _C_FLT:
            sm.fmethod(object, setSel, [_value floatValue]);
            break;
        
          case _C_DBL:
            sm.dmethod(object, setSel, [_value doubleValue]);
            break;

          case _C_CHARPTR:
            if (_value == nil)
              sm.strmethod(object, setSel, NULL);
            else {
              unsigned clen;
              if ((clen = [_value cStringLength]) == 0)
                sm.strmethod(object, setSel, "");
              else {
                char *buf;
                buf = malloc(clen + 4);
                [_value getCString:buf]; buf[clen] = '\0';
                sm.strmethod(object, setSel, buf);
		if (buf != NULL) free(buf);
              }
            }
            break;
            
          default:
            NSLog(@"%@: cannot set type '%c' yet (key=%s, method=%@) ..",
                  self, info->retType, info->ckey,
                  NSStringFromSelector(setSel));
            [NSException raise:@"WORuntimeException"
                         format:
                           @"in WOKeyPathAssociation %@: "
                           @"cannot set type '%c' yet (key=%s, method=%@)",
                           self, info->retType, info->ckey,
                           NSStringFromSelector(setSel)];
            return NO;
        }
        return YES;
      }
      else {
        NSLog(@"%@: did not find method %@ in object %@",
              self, NSStringFromSelector(setSel), object);
        return NO;
      }
    }
  }
  else if (info->type == WOKeyType_kvc) { // takeValue:forKey:..
    NSCAssert(info->extra.key, @"no key object set ..");
#if NeXT_Foundation_LIBRARY || COCOA_Foundation_LIBRARY || \
    APPLE_FOUNDATION_LIBRARY
    if([object isKindOfClass:NSCFDictionaryClass] &&
       !_CFDictionaryIsMutable((CFDictionaryRef)object))
        return NO;
#endif
    [object takeValue:_value forKey:info->extra.key];
    return YES;
  }
  else if (info->type == WOKeyType_binding) { // setValue:forBinding:
    NSCAssert(info->extra.key, @"no key object set ..");
    [object setValue:_value forBinding:info->extra.key];
    return YES;
  }
  else {
    NSLog(@"%@: Could not set value for key '%s'.", self, info->ckey);
    return NO;
  }
}

- (void)setValue:(id)_value inComponent:(WOComponent *)_component {
  if (debugOn)
    NSLog(@"%@: set value %@ component %@", self, _value, _component);
  
  _setValue(self, _value, _component);
}
- (id)valueInComponent:(WOComponent *)_component {
#if DEBUG
  volatile id result;
  if (debugOn)
    NSLog(@"%@: get value in component %@", self, _component);
  
#if USE_EXCEPTION_HANDLERS
  NS_DURING {
#endif
    result = (self->size > 1)
      ? _getValue(self, _component)
      : _getOneValue(self, _component);
#if USE_EXCEPTION_HANDLERS
  }
  NS_HANDLER {
    fprintf(stderr, "during evaluation of keypath %s:\n  %s\n",
            [[self description] cString],
            [[localException description] cString]);
    fflush(stderr);
    [localException raise];
  }
  NS_ENDHANDLER;
#endif
  return result;
#else
  if (debugOn)
    NSLog(@"%@: get value in component %@", self, _component);
  
  return (self->size > 1)
    ? _getValue(self, _component)
    : _getOneValue(self, _component);
#endif
}

- (BOOL)isValueConstant {
  return NO;
}
- (BOOL)isValueSettable {
  return YES;
}

/* special values */

- (void)setUnsignedIntValue:(unsigned int)_value
  inComponent:(WOComponent *)_wo
{
  WOKeyPathComponent *info;
  
  if (debugOn)
    NSLog(@"%@: set uint value %i in component %@", self, _value, _wo);
  
  if (self->size > 1) {
    _setValue(self, uintNumObj(_value), _wo);
    return;
  }

  info = (WOKeyPathComponent *)self->keyPath;
  NSCAssert(info->keyLen < 255, @"keysize to big ..");
    
  _fillInfo(self, _wo, info);
    
  if (info->type == WOKeyType_method) { /* determine set-selector */
    if (info->retType == _C_CHR || info->retType == _C_UCHR ||
	info->retType == _C_INT || info->retType == _C_UINT) {
      SEL             setSel;
      WOSetMethodType sm;
        
      setSel = _getSetSel(info->ckey, info->keyLen);
      sm.method = [_wo methodForSelector:setSel];
      NSAssert1(sm.method, @"didn't find method for key %s", info->ckey);
        
      switch (info->retType) {
          case _C_CHR: {
            if (((int)_value < -126) || ((int)_value > 127))
              NSLog(@"%@: value (%i) out of range for char !", self, _value);
            sm.cmethod(_wo, setSel, (char)_value);
            break;
          }
          case _C_UCHR: {
            if ((_value < 0) || (_value > 255))
              NSLog(@"%@: value (%i) out of range for uchar !", self, _value);
            sm.ucmethod(_wo, setSel, (unsigned char)_value);
            break;
          }
          case _C_INT: {
            sm.imethod(_wo, setSel, (int)_value);
            break;
          }
          case _C_UINT: {
            sm.uimethod(_wo, setSel, (unsigned int)_value);
            break;
          }

          default:
            [NSException raise:@"WORuntimeException"
                         format:
                           @"in WOKeyPathAssociation %@: "
                           @"does not handle type %c",
                           self, info->retType];
            break;
      }
    }
    else {
      // usual setValue
        _setValue(self, uintNumObj(_value), _wo);
    }
    return;
  }

  if (info->type == WOKeyType_kvc) { // takeValue:forKey:..
    NSCAssert(info->extra.key, @"no key object set ..");
    [_wo takeValue:uintNumObj(_value) forKey:info->extra.key];
    return;
  }
  if (info->type == WOKeyType_binding) { // setValue:forBinding:
    NSCAssert(info->extra.key, @"no key object set ..");
    [_wo setValue:uintNumObj(_value) forBinding:info->extra.key];
    return;
  }
  
  NSLog(@"%@: Could not set value for key '%s'.", self, info->ckey);
}
- (unsigned int)unsignedIntValueInComponent:(WOComponent *)_component {
  WOKeyPathComponent  *info;
  WOReturnValueHolder retValue;
    
  if (debugOn)
    NSLog(@"%@: get uint value in component %@", self, _component);
  
  if (self->size > 1)
    return [_getValue(self, _component) unsignedIntValue];

  info     = (WOKeyPathComponent *)self->keyPath;
  retValue = _getComponentValue(self, _component, info);

  if (info->type == WOKeyType_method) {
    switch (info->retType) {
      case _C_UINT: return retValue.uint;
      case _C_INT:  return retValue.sint;
      case _C_UCHR: return retValue.c;
      case _C_CHR:  return retValue.c;
      case _C_SHT:  return retValue.ss;
      case _C_USHT: return retValue.us;
    }
    return [_objectify(info->retType, &retValue) unsignedIntValue];
  }

#if 0
  NSLog(@"ret value object for key '%s' is 0x%08X",
	info->ckey, retValue.object);
  NSLog(@"ret value object class is %@", [retValue.object class]);
#endif
  return [retValue.object unsignedIntValue];
}

- (void)setIntValue:(int)_value inComponent:(WOComponent *)_wo {
  WOKeyPathComponent *info;
  
  if (debugOn)
    NSLog(@"%@: set int value %i in component %@", self, _value, _wo);
  
  if (self->size > 1) {
    _setValue(self, intNumObj(_value), _wo);
    return;
  }

  info = (WOKeyPathComponent *)self->keyPath;
  NSCAssert(info->keyLen < 255, @"keysize to big ..");
    
  _fillInfo(self, _wo, info);
    
  if (info->type == WOKeyType_method) { // determine set-selector
      if (info->retType == _C_CHR || info->retType == _C_UCHR ||
          info->retType == _C_INT || info->retType == _C_UINT) {
        SEL             setSel;
        WOSetMethodType sm;
        
        setSel = _getSetSel(info->ckey, info->keyLen);
        sm.method = [_wo methodForSelector:setSel];
        NSAssert1(sm.method, @"didn't find method for key %s", info->ckey);
        
        switch (info->retType) {
          case _C_CHR: {
            if (((int)_value < -126) || ((int)_value > 127))
              NSLog(@"%@: value (%i) out of range for char !", self, _value);
            sm.cmethod(_wo, setSel, (char)_value);
            break;
          }
          case _C_UCHR: {
            if ((_value < 0) || (_value > 255))
              NSLog(@"%@: value (%i) out of range for uchar !", self, _value);
            sm.ucmethod(_wo, setSel, (unsigned char)_value);
            break;
          }
          case _C_INT: {
            sm.imethod(_wo, setSel, (int)_value);
            break;
          }
          case _C_UINT: {
            sm.uimethod(_wo, setSel, (unsigned int)_value);
            break;
          }

          default:
            [NSException raise:@"WORuntimeException"
                         format:
                           @"in WOKeyPathAssociation %@: "
                           @"does not handle type %c",
                           self, info->retType];
            break;
        }
      }
      else {
        // usual setValue
        _setValue(self, intNumObj(_value), _wo);
      }
      return;
  }

  if (info->type == WOKeyType_kvc) { // takeValue:forKey:
    NSCAssert(info->extra.key, @"no key object set ..");
    [_wo takeValue:intNumObj(_value) forKey:info->extra.key];
    return;
  }
  
  if (info->type == WOKeyType_binding) { // setValue:forBinding:
    NSCAssert(info->extra.key, @"no key object set ..");
    [_wo setValue:intNumObj(_value) forBinding:info->extra.key];
    return;
  }

  NSLog(@"%@: Could not set value for key '%s'.", self, info->ckey);
}
- (int)intValueInComponent:(WOComponent *)_component {
  WOKeyPathComponent  *info;
  WOReturnValueHolder retValue;

  if (debugOn)
    NSLog(@"%@: get int value in component %@", self, _component);
  
  if (self->size > 1)
    return [_getValue(self, _component) intValue];

  info     = (WOKeyPathComponent *)self->keyPath;
  retValue = _getComponentValue(self, _component, info);

  if (info->type != WOKeyType_method)
    return [retValue.object intValue];

  switch (info->retType) {
    case _C_UINT: return retValue.uint;
    case _C_INT:  return retValue.sint;
    case _C_UCHR: return retValue.c;
    case _C_CHR:  return retValue.c;
    case _C_SHT:  return retValue.ss;
    case _C_USHT: return retValue.us;
    default:      return [_objectify(info->retType, &retValue) intValue];
  }
}

- (void)setBoolValue:(BOOL)_value inComponent:(WOComponent *)_wo {
  WOKeyPathComponent *info;
  
  if (debugOn)
    NSLog(@"%@: set bool value %i in component %@", self, _value, _wo);
  
  if (self->size > 1) {
    _setValue(self, [NumberClass numberWithBool:_value], _wo);
    return;
  }

  info = (WOKeyPathComponent *)self->keyPath;
  NSCAssert(info->keyLen < 255, @"keysize to big ..");
    
  _fillInfo(self, _wo, info);
    
  if (info->type == WOKeyType_method) { // determine set-selector
      if (info->retType == _C_CHR || info->retType == _C_UCHR ||
          info->retType == _C_INT || info->retType == _C_UINT) {
        SEL             setSel;
        WOSetMethodType sm;
        
        setSel = _getSetSel(info->ckey, info->keyLen);
        sm.method = [_wo methodForSelector:setSel];
        NSAssert1(sm.method, @"didn't find method for key %s", info->ckey);
        
        switch (info->retType) {
          case _C_CHR: {
            sm.cmethod(_wo, setSel, (char)_value);
            break;
          }
          case _C_UCHR: {
            sm.ucmethod(_wo, setSel, (unsigned char)_value);
            break;
          }
          case _C_INT: {
            sm.imethod(_wo, setSel, (int)_value);
            break;
          }
          case _C_UINT: {
            sm.uimethod(_wo, setSel, (unsigned int)_value);
            break;
          }

          default:
            [NSException raise:@"WORuntimeException"
                         format:
                           @"in WOKeyPathAssociation %@: "
                           @"does not handle type %c",
                           self, info->retType];
            break;
        }
      }
      else {
        // usual setValue
        _setValue(self, [NumberClass numberWithBool:_value], _wo);
      }
  }
  else if (info->type == WOKeyType_kvc) { // takeValue:forKey:
      NSCAssert(info->extra.key, @"no key object set ..");
      [_wo takeValue:[NumberClass numberWithBool:_value]
           forKey:info->extra.key];
  }
  else if (info->type == WOKeyType_binding) { // setValue:forBinding:
      NSCAssert(info->extra.key, @"no key object set ..");
      [_wo setValue:[NumberClass numberWithBool:_value]
           forBinding:info->extra.key];
  }
  else {
      NSLog(@"%@: Could not set value for key '%s'.", self, info->ckey);
  }
}
- (BOOL)boolValueInComponent:(WOComponent *)_component {
  if (debugOn)
    NSLog(@"%@: get bool value in component %@", self, _component);
  
  if (self->size > 1)
    return [_getValue(self, _component) boolValue];
  else {
    WOKeyPathComponent  *info;
    WOReturnValueHolder retValue;

    info     = (WOKeyPathComponent *)self->keyPath;
    retValue = _getComponentValue(self, _component, info);

    if (info->type == WOKeyType_method) {
      switch (info->retType) {
        case _C_UINT: return retValue.uint;
        case _C_INT:  return retValue.sint;
        case _C_UCHR: return retValue.c;
        case _C_CHR:  return retValue.c;
        case _C_SHT:  return retValue.ss;
        case _C_USHT: return retValue.us;

        default:
          return [_objectify(info->retType, &retValue) boolValue];
      }
    }
    else
      return [retValue.object boolValue];
  }
}

- (void)setStringValue:(NSString *)_value inComponent:(WOComponent *)_wo {
  if (debugOn)
    NSLog(@"%@: set string value '%@' in component %@", self, _value, _wo);
  
  _setValue(self, _value, _wo);
}
- (NSString *)stringValueInComponent:(WOComponent *)_component {
  WOKeyPathComponent  *info;
  WOReturnValueHolder retValue;
    
  if (debugOn)
    NSLog(@"%@: get string value in component %@", self, _component);
  
  if (self->size > 1)
    return [_getValue(self, _component) stringValue];

  info     = (WOKeyPathComponent *)self->keyPath;
  retValue = _getComponentValue(self, _component, info);

  if (info->type != WOKeyType_method)
    return [retValue.object stringValue];

  switch (info->retType) {
    case _C_UINT:
      if (IS_UNUMSTR(retValue.uint)) return numStrings[retValue.uint];
      return [StringClass stringWithFormat:@"%u", retValue.uint];
    case _C_INT:
      if (IS_NUMSTR(retValue.sint)) return numStrings[retValue.sint];
      return [StringClass stringWithFormat:@"%d", retValue.sint];
    case _C_UCHR:
      if (IS_UNUMSTR(retValue.c)) return numStrings[retValue.c];
      return [StringClass stringWithFormat:@"%d", (int)retValue.c];
    case _C_CHR:
      if (IS_NUMSTR((signed char)retValue.c)) return numStrings[retValue.c];
      return [StringClass stringWithFormat:@"%d", (int)retValue.c];
    case _C_SHT:
      if (IS_NUMSTR(retValue.ss)) return numStrings[retValue.ss];
      return [StringClass stringWithFormat:@"%d", (int)retValue.ss];
    case _C_USHT:
      if (IS_UNUMSTR(retValue.us)) return numStrings[retValue.us];
      return [StringClass stringWithFormat:@"%d", (int)retValue.us];
    
#if 0      
    case _C_FLT:
      return [StringClass stringWithFormat:@"%0.7g", retValue.flt];
#endif
    default:
      return [_objectify(info->retType, &retValue) stringValue];
  }
}

/* NSCoding */

- (void)encodeWithCoder:(NSCoder *)_coder {
  [_coder encodeObject:[self keyPath]];
}
- (id)initWithCoder:(NSCoder *)_coder {
  return [self initWithKeyPath:[_coder decodeObject]];
}

/* NSCopying */

- (id)copyWithZone:(NSZone *)_zone {
  /* keypath associations are immutable */
  return [self retain];
}

/* description */

- (NSString *)description {
  return [StringClass stringWithFormat:@"<%@[0x%08X]: keyPath=%@>",
                        NSStringFromClass([self class]), self,
                        [self keyPath]];
}

@end /* WOKeyPathAssociation */