//
//  SharingDictionaryTransformer.m
//  pithos-macos
//
// Copyright 2011 GRNET S.A. All rights reserved.
//
// Redistribution and use in source and binary forms, with or
// without modification, are permitted provided that the following
// conditions are met:
// 
//   1. Redistributions of source code must retain the above
//      copyright notice, this list of conditions and the following
//      disclaimer.
// 
//   2. Redistributions in binary form must reproduce the above
//      copyright notice, this list of conditions and the following
//      disclaimer in the documentation and/or other materials
//      provided with the distribution.
// 
// THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS
// OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
// USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
// AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
// ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
// 
// The views and conclusions contained in the software and
// documentation are those of the authors and should not be
// interpreted as representing official policies, either expressed
// or implied, of GRNET S.A.

#import "SharingDictionaryTransformer.h"

@implementation SharingDictionaryTransformer

+ (Class)transformedValueClass {
	return [NSMutableDictionary class];
}

+ (BOOL)allowsReverseTransformation {
	return YES;
}

- (id)transformedValue:(id)value {
    NSMutableDictionary *sharingDictionary = [NSMutableDictionary dictionary];
    
    if (value == nil)
        return sharingDictionary;
    
    NSRange readRange = [(NSString *)value rangeOfString:@"read=" options:NSCaseInsensitiveSearch];
    NSUInteger readStart = readRange.location + readRange.length;
    NSRange writeRange = [(NSString *)value rangeOfString:@"write=" options:NSCaseInsensitiveSearch];
    NSUInteger writeStart = writeRange.location + writeRange.length;
    if (writeRange.length == 0) {
        if (readRange.length == 0) {
            return sharingDictionary;
        }
        for (NSString *readUser in [[(NSString *)value substringFromIndex:readStart] componentsSeparatedByString:@","]) {
            [sharingDictionary setValue:@"read" forKey:readUser];
        }
    } else if (readRange.length == 0) {
        for (NSString *writeUser in [[(NSString *)value substringFromIndex:writeStart] componentsSeparatedByString:@","]) {
            [sharingDictionary setValue:@"write" forKey:writeUser];
        }
    } else if (readRange.location < writeRange.location) {
        NSRange semicolonRange = [(NSString *)value rangeOfString:@";"];
        for (NSString *readUser in [[(NSString *)value substringWithRange:NSMakeRange(readStart, semicolonRange.location - readStart)] componentsSeparatedByString:@","]) {
            [sharingDictionary setValue:@"read" forKey:readUser];
        }
        for (NSString *writeUser in [[(NSString *)value substringFromIndex:writeStart] componentsSeparatedByString:@","]) {
            [sharingDictionary setValue:@"write" forKey:writeUser];
        }        
    } else {
        NSRange semicolonRange = [(NSString *)value rangeOfString:@";"];
        for (NSString *readUser in [[(NSString *)value substringFromIndex:readStart] componentsSeparatedByString:@","]) {
            [sharingDictionary setValue:@"read" forKey:readUser];
        }                
        for (NSString *writeUser in [[(NSString *)value substringWithRange:NSMakeRange(writeStart, semicolonRange.location - writeStart)] componentsSeparatedByString:@","]) {
            [sharingDictionary setValue:@"write" forKey:writeUser];
        }
    }
    
    return sharingDictionary;
}

- (id)reverseTransformedValue:(id)value {
    if (value == nil || ([(NSMutableDictionary *)value count] == 0))
        return nil;
    
    NSString *readSharingString = nil;
    NSArray *readUsers = [(NSMutableDictionary *)value allKeysForObject:@"read"];
    if ([readUsers count])
        readSharingString = [NSString stringWithFormat:@"read=%@", [readUsers componentsJoinedByString:@","]];
    NSString *writeSharingString = nil;
    
    NSArray *writeUsers = [(NSMutableDictionary *)value allKeysForObject:@"write"];
    if ([writeUsers count])
        writeSharingString = [NSString stringWithFormat:@"write=%@", [writeUsers componentsJoinedByString:@","]];
        

    if (readSharingString) {
        if (writeSharingString) {
            return [NSString stringWithFormat:@"%@;%@", readSharingString, writeSharingString];
        }
        return readSharingString;
    } else {
        return writeSharingString;
    }
}

+ (void)initialize {
    [[NSValueTransformer class] setValueTransformer:[self new] forName:@"SharingDictionaryTransformer"];
}

@end