EcUserDefaults.m

/** Enterprise Control Configuration and Logging

   Copyright (C) 2012 Free Software Foundation, Inc.

   Written by: Richard Frith-Macdonald <rfm@gnu.org>
   Date: Febrary 2010
   Originally developed from 1996 to 2012 by Brainstorm, and donated to
   the FSF.

   This file is part of the GNUstep project.

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 3 of the License, or (at your option) any later version.

   This library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with this library; if not, write to the Free
   Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
   Boston, MA 02111 USA.

   */

#import	<Foundation/NSDictionary.h>
#import	<Foundation/NSException.h>
#import	<Foundation/NSInvocation.h>
#import	<Foundation/NSLock.h>
#import	<Foundation/NSMethodSignature.h>
#import	<Foundation/NSNotification.h>
#import	<Foundation/NSProxy.h>
#import	<Foundation/NSString.h>

#import	"EcUserDefaults.h"

static NSUserDefaults		*latest = nil;
static NSLock 			*lock = nil;
static NSMutableDictionary	*lifetimes = nil;
static NSMutableDictionary	*overrides = nil;
static NSTimeInterval		defaultDuration = (72.0 * 60.0 * 60.0);

@interface	EcUserDefaults : NSProxy
{
  NSUserDefaults	*defs;
  NSString		*prefix;
}
- (id) initWithPrefix: (NSString*)p;
- (NSString*) _getKey: (NSString*)baseKey;
@end

@implementation	EcUserDefaults

+ (void) initialize
{
  if (nil == lock)
    {
      lock = [NSLock new];
      lifetimes = [NSMutableDictionary new];
      overrides = [NSMutableDictionary new];
      [[NSObject leakAt: &lock] release];
      [[NSObject leakAt: &latest] release];
      [[NSObject leakAt: &lifetimes] release];
      [[NSObject leakAt: &overrides] release];
    }
}

- (NSArray*) arrayForKey: (NSString*)aKey
{
  return [defs arrayForKey: [self _getKey: aKey]];
}

- (BOOL) boolForKey: (NSString*)aKey
{
  return [defs boolForKey: [self _getKey: aKey]];
}

- (NSDictionary*) commandExpiries
{
  return [defs commandExpiries];
}

- (id) commandObjectForKey: (NSString*)aKey
{
  return [defs commandObjectForKey: aKey];
}

- (NSData*) dataForKey: (NSString*)aKey
{
  return [defs dataForKey: [self _getKey: aKey]];
}

- (void) dealloc
{
  [lock lock];
  if (latest == (NSUserDefaults*)self)
    {
      latest = nil;
    }
  [lock unlock];
  [prefix release];
  [defs release];
  [super dealloc];
}

- (NSString*) defaultsPrefix
{
  return prefix;
}

- (NSDictionary*) dictionaryForKey: (NSString*)aKey
{
  return [defs dictionaryForKey: [self _getKey: aKey]];
}

- (double) doubleForKey: (NSString*)aKey
{
  return [defs doubleForKey: [self _getKey: aKey]];
}

- (float) floatForKey: (NSString*)aKey
{
  return [defs floatForKey: [self _getKey: aKey]];
}

- (void) forwardInvocation: (NSInvocation*)anInvocation
{
  [anInvocation invokeWithTarget: defs];
}

- (NSString*) _getKey: (NSString*)aKey
{
  /* Make sure we have the prefix.
   */
  if (nil != prefix)
    {
      if (NO == [aKey hasPrefix: prefix])
	{
	  aKey = [prefix stringByAppendingString: aKey];
	}
      if (nil == [defs objectForKey: aKey])
	{
	  /* Nothing found for key ... try without the prefix.
	   */
	  aKey = [aKey substringFromIndex: [prefix length]];
	}
    }
  return aKey;
}

- (id) init
{
  [self release];
  return nil;
}

- (id) initWithPrefix: (NSString*)p
{
  NSMutableArray	*list;

  [lock lock];
  defs = [[NSUserDefaults standardUserDefaults] retain];
  if (0 == [p length])
    {
      p = [defs stringForKey: @"EcUserDefaultsPrefix"]; 
      if (0 == [p length])
	{
	  p = nil;
	}
    }
  prefix = [p copy];

  /* Make sure the defaults database has our special domains at the start
   * of the search list and in the correct order.
   */
  list = [[defs searchList] mutableCopy];
  [list removeObject: @"EcCommand"];
  [list removeObject: @"EcConfiguration"];
  [list insertObject: @"EcCommand" atIndex: 0]; 
  [list insertObject: @"EcConfiguration" atIndex: 1]; 
  [defs setSearchList: list];
  [list release];
  ASSIGN(latest, (NSUserDefaults*)self);
  [lock unlock];
  return self;
}

- (NSInteger) integerForKey: (NSString*)aKey
{
  return [defs integerForKey: [self _getKey: aKey]];
}

- (NSString*) key: (NSString*)aKey
{
  /* Make sure we have the prefix.
   */
  if (nil != prefix && NO == [aKey hasPrefix: prefix])
    {
      aKey = [prefix stringByAppendingString: aKey];
    }
  return aKey;
}

- (NSMethodSignature*) methodSignatureForSelector: (SEL)aSelector
{
  if (class_respondsToSelector(object_getClass(self), aSelector))
    {
      return [super methodSignatureForSelector: aSelector];
    }
  return [defs methodSignatureForSelector: aSelector];
}

- (id) objectForKey: (NSString*)aKey
{
  return [defs objectForKey: [self _getKey: aKey]];
}

- (void) purgeSettings
{
  [defs purgeSettings];
}

- (void) removeObjectForKey: (NSString*)aKey
{
  return [defs removeObjectForKey: [self _getKey: aKey]];
}

- (void) revertSettings
{
  [defs revertSettings];
}

- (void) setBool: (BOOL)value forKey: (NSString*)aKey
{
  [defs setBool: value forKey: aKey];
}

- (BOOL) setCommand: (id)val forKey: (NSString*)key
{
  return [defs setCommand: val forKey: key];
}

- (BOOL) setCommand: (id)val
	     forKey: (NSString*)key
	   lifetime: (NSTimeInterval)t
{
  return [defs setCommand: val forKey: key lifetime: t];
}

- (void) setDouble: (double)value forKey: (NSString*)aKey
{
  [defs setDouble: value forKey: aKey];
}

- (void) setFloat: (float)value forKey: (NSString*)aKey
{
  [defs setFloat: value forKey: aKey];
}

- (void) setInteger: (NSInteger)value forKey: (NSString*)aKey
{
  [defs setInteger: value forKey: aKey];
}

- (void) setObject: (id)anObject forKey: (NSString*)aKey
{
  [defs setObject: anObject forKey: aKey];
}

- (NSArray*) stringArrayForKey: (NSString*)aKey
{
  return [defs stringArrayForKey: [self _getKey: aKey]];
}

- (NSString*) stringForKey: (NSString*)aKey
{
  return [defs stringForKey: [self _getKey: aKey]];
}

- (NSUserDefaults*) target
{
  return defs;
}

@end


@implementation	NSUserDefaults (EcUserDefaults)

+ (NSUserDefaults*) prefixedDefaults
{
  NSUserDefaults	*defs = nil;

  if (Nil != [EcUserDefaults class])
    {
      [lock lock];
      defs = [latest retain];
      [lock unlock];
    }
  return [defs autorelease];
}

+ (void) setDefaultLifetime: (NSTimeInterval)t
{
  if (t != t || t <= 0)
    {
      t = 72.0 * 60.0 * 60.0;
    }
  defaultDuration = t;
}

+ (NSUserDefaults*) userDefaultsWithPrefix: (NSString*)aPrefix
{
  return (NSUserDefaults*)[[[EcUserDefaults alloc]
    initWithPrefix: aPrefix] autorelease];
}

- (NSDictionary*) commandExpiries
{
  NSDictionary	*d;

  [lock lock];
  d = [lifetimes copy];
  [lock unlock];
  return [d autorelease];
}

- (id) commandObjectForKey: (NSString*)aKey
{
  id	val;

  [lock lock];
  val = [[overrides objectForKey: aKey] retain];
  [lock unlock];
  return [val autorelease];
}

- (NSDictionary*) configuration
{
  return [self volatileDomainForName: @"EcConfiguration"];
}

- (NSString*) defaultsPrefix
{
  return nil;	// No prefix in use ... this is not a proxy
}

- (NSString*) key: (NSString*)aKey
{
  NSString	*prefix = [self defaultsPrefix];

  /* Make sure we have the prefix.
   */
  if (nil != prefix && NO == [aKey hasPrefix: prefix])
    {
      aKey = [prefix stringByAppendingString: aKey];
    }
  return aKey;
}

- (void) purgeSettings
{
  NSDictionary	*new = nil;
  BOOL		changed = NO;
  NSEnumerator	*enumerator;
  NSString	*key;
  NSDate	*now = [NSDate date];

  [lock lock];
  enumerator = [[lifetimes allKeys] objectEnumerator];
  while (nil != (key = [enumerator nextObject]))
    {
      NSDate	*expires = [lifetimes objectForKey: key];

      if ([expires laterDate: now] != expires)
	{
	  [lifetimes removeObjectForKey: key];
	  [overrides removeObjectForKey: key];
	  changed = YES;
	}
    }
  if (YES == changed && [overrides count] > 0)
    {
      new = [overrides copy];
    }
  [lock unlock];
  if (YES == changed)
    {
      [self removeVolatileDomainForName: @"EcCommand"];
      if (new != nil)
	{
	  [self setVolatileDomain: new forName: @"EcCommand"];
          [new release];
	}
      [[NSNotificationCenter defaultCenter] postNotificationName:
	NSUserDefaultsDidChangeNotification object: self];
    }
}

- (void) revertSettings
{
  BOOL		changed = NO;

  [lock lock];
  if (YES == (changed = [overrides count] > 0 ? YES : NO))
    {
      [lifetimes removeAllObjects];
      [overrides removeAllObjects];
    }
  [lock unlock];
  if (YES == changed)
    {
      [self removeVolatileDomainForName: @"EcCommand"];
      [[NSNotificationCenter defaultCenter] postNotificationName:
	NSUserDefaultsDidChangeNotification object: self];
    }
}

- (BOOL) setCommand: (id)val forKey: (NSString*)key
{
  return [self setCommand: val forKey: key lifetime: defaultDuration];
}

- (BOOL) setCommand: (id)val forKey: (NSString*)key lifetime: (NSTimeInterval)t
{
  NSDictionary	*new = nil;
  BOOL		changed = NO;
  id		old;
  
  [lock lock];
  old = [overrides objectForKey: key];
  if (old != val && NO == [old isEqual: val])
    {
      if (nil == val)
	{
	  [overrides removeObjectForKey: key];
	  [lifetimes removeObjectForKey: key];
	}
      else
	{
	  [overrides setObject: val forKey: key];
	  [lifetimes setObject: [NSDate dateWithTimeIntervalSinceNow: t]
		        forKey: key];
	}
      if ([overrides count] > 0)
	{
	  new = [overrides copy];
	}
      changed = YES;
    }
  else if (old != nil)
    {
      /* No change to the value, only to its expiry time.
       */
      [lifetimes setObject: [NSDate dateWithTimeIntervalSinceNow: t]
		   forKey: key];
    }
  [lock unlock];

  if (YES == changed)
    {
      [self removeVolatileDomainForName: @"EcCommand"];
      if (nil != new)
	{
	  [self setVolatileDomain: new forName: @"EcCommand"];
          [new release];
	}
      [[NSNotificationCenter defaultCenter] postNotificationName:
	NSUserDefaultsDidChangeNotification object: self];
    }
  return changed;
}

- (BOOL) setConfiguration: (NSDictionary*)config
{
  NSDictionary	*old = [self volatileDomainForName: @"EcConfiguration"];

  if (old != config && NO == [old isEqual: config])
    {
      if (nil != old)
	{
	  [self removeVolatileDomainForName: @"EcConfiguration"];
	}
      if (nil != config)
	{
	  [self setVolatileDomain: config forName: @"EcConfiguration"];
	}
      [[NSNotificationCenter defaultCenter] postNotificationName:
	NSUserDefaultsDidChangeNotification
	object: self];
      return YES;
    }
  return NO;
}

@end