YAJLGen.m

//
//  YAJLGen.m
//  YAJL
//
//  Created by Gabriel Handford on 7/19/09.
//  Copyright 2009. All rights reserved.
//
//  Permission is hereby granted, free of charge, to any person
//  obtaining a copy of this software and associated documentation
//  files (the "Software"), to deal in the Software without
//  restriction, including without limitation the rights to use,
//  copy, modify, merge, publish, distribute, sublicense, and/or sell
//  copies of the Software, and to permit persons to whom the
//  Software is furnished to do so, subject to the following
//  conditions:
//
//  The above copyright notice and this permission notice shall be
//  included in all copies or substantial portions of the Software.
//
//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
//  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
//  OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
//  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
//  HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
//  WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
//  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
//  OTHER DEALINGS IN THE SOFTWARE.
//

#import "YAJLGen.h"
#import "GTMBase64.h"

NSString *const YAJLGenInvalidObjectException = @"YAJLGenInvalidObjectException";

@implementation YAJLGen

- (id)init {
  return [self initWithGenOptions:YAJLGenOptionsNone indentString:@""];
}

- (id)initWithGenOptions:(YAJLGenOptions)genOptions indentString:(NSString *)indentString {
  if ((self = [super init])) {
    genOptions_ = genOptions;
    yajl_gen_config cfg = { 
      ((genOptions & YAJLGenOptionsBeautify) ? 1 : 0),
      [indentString UTF8String]
    };    
    gen_ = yajl_gen_alloc(&cfg, NULL);    
  }
  return self;
}

- (void)dealloc { 
  if (gen_ != NULL) yajl_gen_free(gen_);
  [super dealloc];
}

- (void)object:(id)obj {  
  if ([obj respondsToSelector:@selector(JSON)]) {
    return [self object:[obj JSON]];
  } else if ([obj isKindOfClass:[NSArray class]]) {
    [self startArray];
    for(id element in obj)
      [self object:element];
    [self endArray];
  } else if ([obj isKindOfClass:[NSDictionary class]]) {
    [self startDictionary];
    for(id key in obj) {
      [self object:key];
      [self object:[obj objectForKey:key]];
    }
    [self endDictionary];
  } else if ([obj isKindOfClass:[NSNumber class]]) {
    if ('c' != *[obj objCType]) {
      [self number:obj];
    } else {
      [self bool:[obj boolValue]];
    }
  } else if ([obj isKindOfClass:[NSString class]]) {
    [self string:obj];
  } else if ([obj isKindOfClass:[NSNull class]]) {
    [self null];
  } else {    
    
    BOOL unknownType = NO;
    if (genOptions_ & YAJLGenOptionsIncludeUnsupportedTypes) {
      // Begin with support for non-JSON representable (PList) types
      if ([obj isKindOfClass:[NSDate class]]) { 
        [self number:[NSNumber numberWithLongLong:round([obj timeIntervalSince1970] * 1000)]];
      } else if ([obj isKindOfClass:[NSData class]]) {
        [self string:[YAJL_GTMBase64 stringByEncodingData:obj]];
      } else if ([obj isKindOfClass:[NSURL class]]) {
        [self string:[obj absoluteString]];
      } else {
        unknownType = YES;
      }
    } else {
      unknownType = YES;
    }
    
    // If we didn't handle special PList types
    if (unknownType) {
      if (!(genOptions_ & YAJLGenOptionsIgnoreUnknownTypes)) {
        [NSException raise:YAJLGenInvalidObjectException format:@"Unknown object type: %@ (%@)", [obj class], obj];
      } else {
        [self null]; // Use null value for unknown type if we are ignoring
      }
    }
  }
}

- (void)null {
  yajl_gen_null(gen_);
}

- (void)bool:(BOOL)b {
  yajl_gen_bool(gen_, b);
}

- (void)number:(NSNumber *)number {
  if ([number isEqualToNumber:[NSDecimalNumber notANumber]]) {
    yajl_gen_null(gen_);
  } else {
    NSString *s = [number stringValue];
    unsigned int length = [s lengthOfBytesUsingEncoding:NSUTF8StringEncoding];
    const char *c = [s UTF8String];
    yajl_gen_number(gen_, c, length);
  }
}

- (void)string:(NSString *)s {
  unsigned int length = [s lengthOfBytesUsingEncoding:NSUTF8StringEncoding];
  const unsigned char *c = (const unsigned char *)[s UTF8String]; 
  yajl_gen_string(gen_, c, length);
}

- (void)startDictionary {
  yajl_gen_map_open(gen_);
}

- (void)endDictionary {
  yajl_gen_map_close(gen_);
}

- (void)startArray {
  yajl_gen_array_open(gen_);
}

- (void)endArray {
  yajl_gen_array_close(gen_);
}

- (void)clear {
  yajl_gen_clear(gen_);
}

- (NSString *)buffer {
  const unsigned char *buf;  
  unsigned int len;
  yajl_gen_get_buf(gen_, &buf, &len); 
  NSString *s = [NSString stringWithUTF8String:(const char*)buf]; 
  return s;
} 

@end