ZXAccountController.m

/*
 * Name: 	ZXAccountController.m
 * Project:	Strongbox
 * Created on:	2008-06-03
 *
 * Copyright (C) 2008 Pierre-Hans Corcoran
 *
 * --------------------------------------------------------------------------
 *  This program is  free software;  you can redistribute  it and/or modify it
 *  under the terms of the GNU General Public License (version 2) as published 
 *  by  the  Free Software Foundation.  This  program  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 General Public License  for  more  details.  You should have 
 *  received  a  copy  of  the  GNU General Public License   along  with  this 
 *  program;   if  not,  write  to  the  Free  Software  Foundation,  Inc., 51 
 *  Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * --------------------------------------------------------------------------
 */

#import "ZXAccountController.h"
#import "ZXAccountMO.h"
#import "ZXCurrencyFormatter.h"
#import "ZXNotification.h"
#import "ZXTransactionController.h"

@interface ZXAccountController (Private)
- (NSString *)uniqueNewName:(NSString *)newDesiredName;
- (void)updateUsedNames;
- (void)validatesNewAccountName:(NSNotification *)aNotification;
@end


@implementation ZXAccountController
@synthesize usedNames, generalMessage, owner;

- (id)init
{
	if(self = [super init]) {
		self.usedNames = [NSMutableDictionary dictionary];
	}
	return self;
}

//! Prepares the content of the controller
/*!
 If there is no accounts, adds one. Registers to validate name change, and sets 
 up used names dictionary.
 \sa updateUsedNames, validatesNewAccountName:
 */
- (void)prepareContent
{
	[super prepareContent];
	[[owner managedObjectContext] processPendingChanges];
	[[owner undoManager] disableUndoRegistration];
	NSFetchRequest *fetchRequest = [[[NSFetchRequest alloc] init] autorelease];
	[fetchRequest setEntity:[NSEntityDescription entityForName:@"Account" 
					    inManagedObjectContext:[self managedObjectContext]]];
	
	NSError *error = nil;
	NSArray *array = [[self managedObjectContext] executeFetchRequest:fetchRequest 
								    error:&error];
	if(array == nil) {
		// FIXME: Real error management needed.
		[[owner undoManager] enableUndoRegistration];
		NSLog(@"Could not load accounts: %@", error);
		return;
	}
	
	if([array count] < 1) {
		[[self newObject] autorelease];
	}
	[self updateUsedNames];
	[[NSNotificationCenter defaultCenter] addObserver:self 
						 selector:@selector(validatesNewAccountName:) 
						     name:ZXAccountNameDidChangeNotification 
						   object:nil];
	[[owner managedObjectContext] processPendingChanges];
	[[owner undoManager] enableUndoRegistration];
}

//! Controls special cases of key-value changes
/*!
 Posts a ZXActiveAccountDidChangeNotification upon selection change.
 */
- (void)setValue:(id)newValue forKey:(id)key
{
	[super setValue:newValue forKey:key];
	if([key isEqual:@"selectionIndex"] || [key isEqual:@"selectionIndexes"]) {
		[ZXNotification postNotificationName:ZXActiveAccountDidChangeNotification 
					      object:self];
	}
}

//! Basic initialization
/*!
 Registers to recalculate balances of selection when account total changes, or 
 when active account changes.
 Also, update the general message when account total or name changes, when 
 active account changes or when transaction selection changes.
 \sa recalculateBalance:
 \sa updateGeneralMessage:
 */
- (void)awakeFromNib
{
	[super awakeFromNib];
	id nc = [NSNotificationCenter defaultCenter];
	id arr = [NSArray arrayWithObjects:ZXAccountTotalDidChangeNotification, 
		  ZXActiveAccountDidChangeNotification, nil];
	for(id note in arr) {
		[nc addObserver:self 
		       selector:@selector(recalculateBalance:) 
			   name:note 
			 object:nil];
	}
	
	arr = [NSArray arrayWithObjects:ZXAccountTotalDidChangeNotification, ZXActiveAccountDidChangeNotification, 
	       ZXAccountNameDidChangeNotification, ZXTransactionSelectionDidChangeNotification, nil];
	for(id note in arr) {
		[nc addObserver:self 
		       selector:@selector(updateGeneralMessage:) 
			   name:note 
			 object:nil];
	}
}

- (void)recalculateBalance:(NSNotification *)note
{
	[[owner managedObjectContext] processPendingChanges];
	[[owner undoManager] disableUndoRegistration];
	if([self valueForKeyPath:@"selection.self"] != NSNoSelectionMarker) {
		[[self valueForKeyPath:@"selection.self"] recalculateBalance:note];
	}
	[[owner managedObjectContext] processPendingChanges];
	[[owner undoManager] enableUndoRegistration];
}

//! Creates a new object
/*! 
 Sets up new name to hard-coded "New Account" (to fix)
 */
- (id)newObject
{
	id obj = [super newObject];
	// FIXME: Hard-coded english
	[obj specialSetName:[self uniqueNewName:@"New Account"]];
	[self.usedNames setValue:[obj objectID] 
			  forKey:[obj valueForKey:@"name"]];
	return obj;
}

//! Sets the name of the account in the notification to avoid conflicts.
/*! 
 This function changes the name of the account in the notification if there is
 a duplicate with existing labels.
 \param aNotification NSNotification containing the new account as object.
 \sa uniqueNewName:
 */
- (void)validatesNewAccountName:(NSNotification *)aNotification
{
	id obj = [aNotification object];
	if(![[self content] containsObject:obj]) return;
	[obj specialSetName:[self uniqueNewName:[obj valueForKey:@"name"]]];
	[self updateUsedNames];
}

//! Generates a non-conflicting name from given name
/*! 
 Returns a new name from the given so that no conflict arises inserting a new 
 account with that name. Appends a number after the name if already exists.
 \param newDesiredName String containing the desired name of the account.
 \return Same or modified name depending on if conflict was found. 
 */
- (NSString *)uniqueNewName:(NSString *)newDesiredName
{
	NSString *allowedName = newDesiredName;
	int counter = 1;
	while([self.usedNames valueForKey:allowedName]) {
		allowedName = [NSString stringWithFormat:@"%@ %d", newDesiredName, counter++];
	}
	return allowedName;
}

//! Updates the dictionary containing the used names
/*!
 Is an expensive method. Uses Core Data fetches to get used names and reconstruct
 the dictionary from scratch.
 */
- (void)updateUsedNames
{
	id desc = [NSEntityDescription entityForName:@"Account" 
			      inManagedObjectContext:[self managedObjectContext]];
	NSFetchRequest *fetchRequest = [[[NSFetchRequest alloc] init] autorelease];
	[fetchRequest setEntity:desc];
	
	NSError *error = nil;
	NSArray *allAccounts = [[self managedObjectContext] executeFetchRequest:fetchRequest 
									  error:&error];
	if(allAccounts == nil) {
		return;
	}
	id usedNamesDict = [NSMutableDictionary dictionaryWithCapacity:[allAccounts count]];
	for(id account in allAccounts) {
		if([account valueForKey:@"name"] == nil) continue;
		[usedNamesDict setValue:[account objectID] 
				 forKey:[account valueForKey:@"name"]];
	}
	self.usedNames = usedNamesDict;
}

- (IBAction)remove:(id)sender
{
	[super remove:sender];
	[self updateUsedNames];
}

- (void)updateGeneralMessage:(NSNotification *)note
{
	static BOOL infiniteLoopBreaker = YES;
	// We postone the update until a first account is created
	if([self valueForKeyPath:@"selection.self"] == NSNoSelectionMarker) {
		if(infiniteLoopBreaker) {
			infiniteLoopBreaker = NO;
			[ZXNotification enqueueNotification:note 
					       postingStyle:NSPostWhenIdle];
		}
		return;
	}
	infiniteLoopBreaker = YES;
	
	id controller = [owner valueForKey:@"transactionController"];
	id count, name;
	count = [self valueForKeyPath:@"selection.transactions.@count"];
	name = [self valueForKeyPath:@"selection.name"];
	if(note != nil && [[controller valueForKeyPath:@"selectionIndexes.count"] intValue] > 1) {
		id partial = [controller valueForKeyPath:@"selectionIndexes.count"];
		id sum = [controller valueForKeyPath:@"selectedObjects.@sum.amount"];
		sum = [[ZXCurrencyFormatter currencyFormatter] stringFromNumber:sum];
		// FIXME: Hard-coded english
		self.generalMessage = [NSString stringWithFormat:@"%@ of %@ transactions in %@. Subtotal: %@", partial, count, name, sum];
	} else {
		id balance;
		balance = [self valueForKeyPath:@"selection.balance"];
		if(!balance) balance = [NSNumber numberWithInt:0];
		balance = [[ZXCurrencyFormatter currencyFormatter] stringFromNumber:balance];
		// FIXME: Hard-coded english
		self.generalMessage = [NSString stringWithFormat:@"%@ transactions in %@. Total: %@", count, name, balance];
	}
}

- (void)dealloc
{
	[[NSNotificationCenter defaultCenter] removeObserver:self];
	[usedNames release];
	[generalMessage release];
	[super dealloc];
}
@end