static NSString* kGeoServerUrl = @"http://maps.google.com/maps/api/geocode/json?latlng=%f,%f&sensor=true&language=en";
static NSString* kLatitudeUserInfoKey = @"latitudeUserInfoKey";
static NSString* kLongitudeUserInfoKey = @"longitudeUserInfoKey";

//
// It's tje solution for replacing MKReverseGeocoder that has problem in China.
//
- (void)startedReverseGeoderWithLatitude:(double)latitude longitude:(double)longitude {
  NSString *url = [NSString stringWithFormat:kGeoServerUrl, latitude, longitude];
  DOUHttpRequest *req = [DOUHttpRequest requestWithURL:[NSURL URLWithString:url] target:self];
  
  NSNumber *lat = [NSNumber numberWithDouble:latitude];
  NSNumber *lon = [NSNumber numberWithDouble:longitude];
  req.userInfo = [NSDictionary dictionaryWithObjectsAndKeys:lat, kLatitudeUserInfoKey, lon, kLongitudeUserInfoKey, nil];
  
  DOUService *service = [DOUService sharedInstance];  
  [service addRequest:req];
}


- (NSDictionary *)addressDictionary:(NSObject *)obj {
  
  NSArray* ary = nil;
  if (IS_INSTANCE_OF(obj, NSDictionary)) {
    NSObject* data = [(NSDictionary*)obj objectForKey:@"results"];
    if (IS_INSTANCE_OF(data, NSArray)) {
      ary = (NSArray*)data;
      NSDictionary *dic = [ary objectAtIndex:0];
      
      NSArray *addressComps = [dic objectForKey:@"address_components"];
      
      //NSString *streetNumber = @"";
      NSString *route = @"";
      NSString *locality = @"";
      NSString *country = @"";
      for (NSDictionary *comp in addressComps) {
        NSArray *types = [comp objectForKey:@"types"];
        NSString *type = [types objectAtIndex:0];
        
//        if ([type isEqualToString:@"street_number"]) {
//          streetNumber = [comp objectForKey:@"long_name"];
//        }
        
        if ([type isEqualToString:@"route"]) {
          route = [comp objectForKey:@"long_name"];
        }
        
        if ([type isEqualToString:@"locality"]) {
          locality = [comp objectForKey:@"long_name"];
        }
        
        if ([type isEqualToString:@"country"]) {
          country = [comp objectForKey:@"long_name"];
        }        
      }
      
      NSDictionary *addressDic = [NSDictionary dictionaryWithObjectsAndKeys:route, kABPersonAddressStreetKey,
                                  locality, kABPersonAddressCityKey,                                        
                                  country, kABPersonAddressCountryKey, nil];
      return addressDic;
    }
  }
  return nil;
}


- (void)requestFinished:(DOUHttpRequest *)req {
  NSError *error = [req error];
  if (!error) {
    DebugLog(@"str:%@", [req responseString]);
    
    NSObject *obj = [[req responseString] JSONValue];
    NSDictionary *addressDic = [self addressDictionary:obj];
    
    CLLocationCoordinate2D coordinate;
    coordinate.latitude = [[req.userInfo objectForKey:kLatitudeUserInfoKey] doubleValue];
    coordinate.longitude = [[req.userInfo objectForKey:kLongitudeUserInfoKey] doubleValue]; 
    MKPlacemark *placemark = [[[MKPlacemark alloc] initWithCoordinate:coordinate 
                                                   addressDictionary:addressDic] autorelease];
    [self reverseGeocoder:nil didFindPlacemark:placemark];
  }
}

- (void)requestFailed:(DOUHttpRequest *)req { 
  [self reverseGeocoder:nil didFailWithError:[req error]];
}


#pragma mark - MKReverseGeocoderDelegate

static NSString * const AppleLanguagesKey = @"AppleLanguages";

- (void)reverseGeocoder:(MKReverseGeocoder *)geocoder didFindPlacemark:(MKPlacemark *)placemark {

  NSArray *array = [[NSUserDefaults standardUserDefaults] objectForKey:AppleLanguagesKey];
  NSString *currentLanguage = [array objectAtIndex:0];
  
  // set current language as english
  [[NSUserDefaults standardUserDefaults] setObject:[NSArray arrayWithObjects:@"zh-Hans", nil] 
                                            forKey:AppleLanguagesKey];
  NSString *local = [placemark.locality lowercaseString];
 
  [AppContext sharedInstance].currentCityUid = local;
  
  // reset current language
  [[NSUserDefaults standardUserDefaults] setObject:[NSArray arrayWithObjects:currentLanguage, nil] 
                                            forKey:AppleLanguagesKey];
}

- (void)reverseGeocoder:(MKReverseGeocoder *)geocoder didFailWithError:(NSError *)error {
  TraceLog(@"reverseGeocoder :%@", [error localizedDescription]);  
}