implemented morphing algorithm and tests

tomknig · Jun 13, 2014 · a00d180 · a00d180
1 parent 085f1cd
commit a00d180
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Showing 5 changed files with 417 additions and 39 deletions.
diff --git a/Classes/NSString+Morphing.h b/Classes/NSString+Morphing.h
@@ -8,6 +8,14 @@
 
 #import <Foundation/Foundation.h>
 
+#define kTOMSDictionaryKeyMergedString @"mergedString"
+#define kTOMSDictionaryKeyAdditionRanges @"additionRanges"
+#define kTOMSDictionaryKeyDeletionRanges @"deletionRanges"
+
 @interface NSString (Morphing)
 
+- (NSDictionary *)toms_mergeIntoString:(NSString *)string;
+
+- (NSDictionary *)toms_mergeIntoString:(NSString *)string lookAheadRadius:(NSUInteger)lookAheadRadius;
+
 @end
diff --git a/Classes/NSString+Morphing.m b/Classes/NSString+Morphing.m
@@ -10,4 +10,101 @@
 
 @implementation NSString (Morphing)
 
+- (NSDictionary *)toms_mergeIntoString:(NSString *)string
+{
+    return [self toms_mergeIntoString:string
+                      lookAheadRadius:6];
+}
+
+- (NSDictionary *)toms_mergeIntoString:(NSString *)string
+                       lookAheadRadius:(NSUInteger)lookAheadRadius
+{
+    NSMutableDictionary *result = [[NSMutableDictionary alloc] init];
+
+    NSMutableString *mergeString = [[NSMutableString alloc] init];
+    NSMutableArray *additionRanges = [[NSMutableArray alloc] init];
+    NSMutableArray *deletionRanges = [[NSMutableArray alloc] init];
+
+    __block int startLocation, endLocation;
+    __block int ownIdx = 0, numberOfInsertions = 0;
+
+    [self toms_enumerateCharacters:^(BOOL *stopOwnEnumeration, const unichar ownChar, NSUInteger index){
+        startLocation = -1;
+        endLocation = -1;
+
+        [string toms_enumerateCharacters:^(BOOL *stopAlienEnumeration, const unichar alienChar, NSUInteger alienIdx){
+            if (ownIdx <= alienIdx++) {
+                if (startLocation < 0) {
+                    startLocation = ownIdx;
+                }
+
+                if (ownChar == alienChar) {
+                    endLocation = alienIdx;
+
+                    [mergeString appendString:[string substringWithRange:NSMakeRange(startLocation, endLocation - startLocation)]];
+                    ownIdx = alienIdx;
+                    *stopAlienEnumeration = YES;
+                }
+
+                if (alienIdx - ownIdx >= lookAheadRadius) {
+                    *stopAlienEnumeration = YES;
+                }
+            }
+        }];
+
+        if (endLocation >= 0) {
+            if (endLocation - startLocation - 1 > 0) {
+                NSRange deletionRange = NSMakeRange(startLocation + numberOfInsertions, endLocation - startLocation - 1);
+                [deletionRanges addObject:[NSValue valueWithRange:deletionRange]];
+            }
+        } else {
+            NSRange additionRange = NSMakeRange(mergeString.length, 1);
+            [additionRanges addObject:[NSValue valueWithRange:additionRange]];
+            [mergeString appendFormat:@"%c", ownChar];
+            ++numberOfInsertions;
+        }
+    }];
+
+
+    NSUInteger alienStringLength = string.length;
+    if (ownIdx < alienStringLength) {
+        NSUInteger deletionLength = alienStringLength - ownIdx;
+        NSRange deletionRange = NSMakeRange(mergeString.length, deletionLength);
+        [deletionRanges addObject:[NSValue valueWithRange:deletionRange]];
+        [mergeString appendString:[string substringWithRange:NSMakeRange(ownIdx, deletionLength)]];
+    }
+
+    result[kTOMSDictionaryKeyMergedString] = mergeString;
+    result[kTOMSDictionaryKeyAdditionRanges] = additionRanges;
+    result[kTOMSDictionaryKeyDeletionRanges] = deletionRanges;
+
+    return result;
+}
+
+
+-(void)toms_enumerateCharacters:(void(^)(BOOL *stop, const unichar aChar, NSUInteger index))enumerationBlock
+{
+    const unichar *chars = CFStringGetCharactersPtr((__bridge CFStringRef)self);
+    BOOL stop = NO;
+
+    if (chars != NULL) {
+        NSUInteger index = 0;
+        while (*chars && !stop) {
+            enumerationBlock(&stop, *chars, index);
+            chars++;
+            index++;
+        }
+    } else {
+        SEL sel = @selector(characterAtIndex:);
+        unichar (*charAtIndex)(id, SEL, NSUInteger) = (typeof(charAtIndex)) [self methodForSelector:sel];
+        for (NSUInteger i = 0; i < self.length; i++) {
+            const unichar c = charAtIndex(self, sel, i);
+            enumerationBlock(&stop, c, i);
+            if (stop) {
+                break;
+            }
+        }
+    }
+}
+
 @end
diff --git a/Classes/TOMSMorphingLabel.h b/Classes/TOMSMorphingLabel.h
@@ -7,6 +7,7 @@
 //
 
 #import <UIKit/UIKit.h>
+#import "NSString+Morphing.h"
 
 @interface TOMSMorphingLabel : UILabel
 

diff --git a/TOMSMorphingLabelExample/TOMSMorphingLabelExampleTests/TOMSMorphingLabelExampleTests.m b/TOMSMorphingLabelExample/TOMSMorphingLabelExampleTests/TOMSMorphingLabelExampleTests.m
-Original file line number
+Diff line change
@@ Expand Up / @@ -7,6 +7,7 @@ @@
     //
     #import <UIKit/UIKit.h>
+    #import "NSString+Morphing.h"
     @interface TOMSMorphingLabel : UILabel
@@ Expand Down @@