#import "KeychainHelper.h"

NS_ASSUME_NONNULL_BEGIN

@implementation KeychainHelper

+ (NSString *)authenticationKey {
    CFDictionaryRef query = (__bridge CFDictionaryRef)@{
        (__bridge NSString *)kSecClass: (__bridge NSString *)kSecClassGenericPassword,
        (__bridge NSString *)kSecAttrService: kKeychainService,
        (__bridge NSString *)kSecAttrAccount: kAuthenticationKeyKeychainKey,
        (__bridge NSString *)kSecReturnData: @YES,
        (__bridge NSString *)kSecMatchLimit: (__bridge NSString *)kSecMatchLimitOne
    };
    
    CFTypeRef result = NULL;
    OSStatus status = SecItemCopyMatching(query, &result);
    
    if (status == errSecSuccess && result != NULL) {
        NSData *keyData = (__bridge NSData *)result;
        NSString *authenticationKey = [[[NSString alloc] initWithData:keyData
                                                             encoding:NSUTF8StringEncoding] autorelease];
        CFRelease(result);
        return authenticationKey;
    }
    
    return nil;
}

+ (OSStatus)setAuthenticationKey:(NSString *)authenticationKey {
    NSData *passwordData = [authenticationKey dataUsingEncoding:NSUTF8StringEncoding];
    
    // First try to update existing item
    CFDictionaryRef query = (__bridge CFDictionaryRef)@{
        (__bridge NSString *)kSecClass: (__bridge NSString *)kSecClassGenericPassword,
        (__bridge NSString *)kSecAttrService: kKeychainService,
        (__bridge NSString *)kSecAttrAccount: kAuthenticationKeyKeychainKey
    };
    
    CFDictionaryRef attributesToUpdate = (__bridge CFDictionaryRef)@{
        (__bridge NSString *)kSecValueData: passwordData
    };
    
    OSStatus status = SecItemUpdate(query, attributesToUpdate);
    
    if (status == errSecItemNotFound) {
        // Item doesn't exist, create new one
        CFDictionaryRef attributes = (__bridge CFDictionaryRef)@{
            (__bridge NSString *)kSecClass: (__bridge NSString *)kSecClassGenericPassword,
            (__bridge NSString *)kSecAttrService: kKeychainService,
            (__bridge NSString *)kSecAttrAccount: kAuthenticationKeyKeychainKey,
            (__bridge NSString *)kSecValueData: passwordData,
            (__bridge NSString *)kSecAttrAccessible: (__bridge NSString *)kSecAttrAccessibleWhenUnlockedThisDeviceOnly
        };
        
        status = SecItemAdd(attributes, NULL);
    }
    
    return status;
}

+ (OSStatus)deleteAuthenticationKey {
    CFDictionaryRef query = (__bridge CFDictionaryRef)@{
        (__bridge NSString *)kSecClass: (__bridge NSString *)kSecClassGenericPassword,
        (__bridge NSString *)kSecAttrService: kKeychainService,
        (__bridge NSString *)kSecAttrAccount: kAuthenticationKeyKeychainKey
    };
    
    OSStatus status = SecItemDelete(query);
    return status;
}

@end

NS_ASSUME_NONNULL_END