OfflineReverseGeocoder

OfflineReverseGeocoder.h

//
//  OfflineReverseGeocoder.h
//  OfflineReverseGeocoder
//
//  Created by Zachry Thayer on 11/4/11.
//  Copyright (c) 2011 Zachry Thayer. All rights reserved.
//

#import <Foundation/Foundation.h>
#import <CoreLocation/CoreLocation.h>

#define kORGCountryKey @"Country"
#define kORGCountryCodeKey @"CountryCode"

#define kORGRegionKey @"Region"
#define kORGRegionCodeKey @"RegionCode"

@interface OfflineReverseGeocoder : NSObject


- (id)initWithDictionary:(NSDictionary*)dictionary;
- (NSDictionary*)reverseGeocodeLocation:(CLLocationCoordinate2D)location;

@end

OfflineReverseGeocoder.m

//
//  OfflineReverseGeocoder.m
//  OfflineReverseGeocoder
//
//  Created by Zachry Thayer on 11/4/11.
//  Copyright (c) 2011 Zachry Thayer. All rights reserved.
//

#import "OfflineReverseGeocoder.h"

@interface OfflineReverseGeocoder ()
{
    NSDictionary *geologicalRegions;
}

- (UIBezierPath*)bezierPathForGeographicalPolygon:(NSArray*)polygonPoints;

- (NSString*)countryForLocation:(CLLocationCoordinate2D)location;
- (NSString*)regionForLocation:(CLLocationCoordinate2D)location inCountry:(NSString*)country;
@end

@implementation OfflineReverseGeocoder

- (id)initWithDictionary:(NSDictionary*)dictionary{
    
    self = [self init];
    if (self) {
        
        geologicalRegions = dictionary;
        
    }
    
    return self;
}

- (NSDictionary*)reverseGeocodeLocation:(CLLocationCoordinate2D)location{
    
    NSString *thisCountryName = [self countryForLocation:location];
    
    if (!thisCountryName) {
        return nil;
    }
    
    NSMutableDictionary *reverseGeocode = [NSMutableDictionary dictionary];
    
    [reverseGeocode setObject:thisCountryName forKey:kORGCountryKey];
    
    NSDictionary *allCountries = [geologicalRegions objectForKey:@"Countries"];
    NSDictionary *thisCountry = [allCountries objectForKey:thisCountryName];
    NSString *thisCountryCode = [thisCountry objectForKey:@"Code"];
    
    [reverseGeocode setObject:thisCountryCode forKey:kORGRegionCodeKey];
    
     NSString *thisRegionName = [self regionForLocation:location inCountry:thisCountryName];
    
    if (thisRegionName){
        
        [reverseGeocode setObject:thisRegionName forKey:kORGRegionKey];
        
        NSDictionary *thisCountriesRegions = [thisCountry objectForKey:@"Regions"];
        NSDictionary *thisRegion = [thisCountriesRegions objectForKey:thisRegionName];
        NSString *thisRegionCode = [thisRegion objectForKey:@"Code"];
        
        [reverseGeocode setObject:thisRegionCode forKey:kORGRegionCodeKey];
        
    }else{
        
        [reverseGeocode setObject:[NSNull null] forKey:kORGRegionKey];
        [reverseGeocode setObject:[NSNull null] forKey:kORGRegionCodeKey];
        
    }
    
    return reverseGeocode;
    
}

#pragma mark - Private Helpers

- (NSString*)countryForLocation:(CLLocationCoordinate2D)location{
    
    NSDictionary *allCountries = [geologicalRegions objectForKey:@"Countries"];
    
    if (!allCountries) {
        return nil;
    }
    
    for (NSString *thisCountryKey in allCountries) {
        NSDictionary *thisCountry = [allCountries objectForKey:thisCountryKey];
        
        if (!thisCountry) {
            return nil;
        }
        
        UIBezierPath *thisCountryPath = [self bezierPathForGeographicalPolygon:[thisCountry objectForKey:@"Polygon"]];
        
        CGPoint locationCGPoint = CGPointMake(location.latitude, location.longitude);
        
        if ([thisCountryPath containsPoint:locationCGPoint]) {
            thisCountryPath = nil;//ARC release
            
            return thisCountryKey;//Return valid match
            
        }
        
    }
    
    return nil;//Nothing was found
    
}

- (NSString*)regionForLocation:(CLLocationCoordinate2D)location inCountry:(NSString*)country{
    
    NSDictionary *allCountries = [geologicalRegions objectForKey:@"Countries"];
    NSDictionary *thisCountry = [allCountries objectForKey:country];
    
    if (!thisCountry) {
        return nil;
    }
    
    NSDictionary *thisCountriesRegions = [thisCountry objectForKey:@"Regions"];
    
    for (NSString *thisRegionKey in thisCountriesRegions) {
        NSDictionary *thisRegion = [thisCountriesRegions objectForKey:thisRegionKey];
        
        if (!thisRegion) {
            return nil;
        }
        
        UIBezierPath *thisRegionPath = [self bezierPathForGeographicalPolygon:[thisRegion objectForKey:@"Polygon"]];
        
        CGPoint locationCGPoint = CGPointMake(location.latitude, location.longitude);
        
        if ([thisRegionPath containsPoint:locationCGPoint]) {
            thisRegionPath = nil;//ARC release
            
            return thisRegionKey;//Return valid match
            
        }
        
    }
    
    
    return nil;//Nothing was found
}

- (UIBezierPath*)bezierPathForGeographicalPolygon:(NSArray*)polygonPoints{
    
    if (!polygonPoints) {
        return nil;
    }
    
    if ([polygonPoints count] < 3) {
        return nil;
    }
    
    UIBezierPath *bezierPath = [[UIBezierPath alloc] init];
    
    for (NSDictionary *thisPoint in polygonPoints) {
        
        CGFloat latitude = [[thisPoint objectForKey:@"lat"] floatValue];
        CGFloat longitude = [[thisPoint objectForKey:@"lon"] floatValue];
        CGPoint locationCGPoint = CGPointMake(latitude, longitude);
        
        [bezierPath addLineToPoint:locationCGPoint];
        
    }
    
    [bezierPath closePath];
    
    return bezierPath;
}

@end