gistfile1.m

//
//  UpgradeController.m
//  Caffeinated
//
//  Created by Curtis Hard on 25/07/2013.
//
//

#import "UpgradeController.h"

@implementation UpgradeController

#define UPGRADE_CLASS_PREFIX @"UpgradeVersion"

- (void)dealloc
{
    [window release], window = nil;
    [context release], context = nil;
    [super dealloc];
}

- (id)initWithManagedObjectContext:(NSManagedObjectContext *)aContext
                             isNew:(BOOL)flag
{
    if( ( self = [super init] ) != nil )
    {
        context = [aContext retain];
        isNew = flag;
    }
    return self;
}

- (void)step
{
    [progressIndicator incrementBy:1];
    [NSThread sleepForTimeInterval:0.001];
}

- (void)upgrade
{
    // we need to check the current DB version
    NSEntityDescription * configEntity = [NSEntityDescription entityForName:@"Config"
                                                     inManagedObjectContext:context];
    
    // find the version
    NSFetchRequest * request = [[[NSFetchRequest alloc] init] autorelease];
    [request setEntity:configEntity];
    [request setFetchLimit:1];
    
    NSError * error = nil;
    NSArray * results = [context executeFetchRequest:request
                                               error:&error];
    
    NSInteger currentVersion = 0;
    Config * config = nil;
    if( [results count] != 0 )
    {
        config = [results objectAtIndex:0];
        currentVersion = [[config version] integerValue];
    } else
        config = [NSEntityDescription insertNewObjectForEntityForName:[configEntity name]
                                               inManagedObjectContext:context];
    
    // find the classes
    NSInteger start = currentVersion;
    NSInteger counter = start;
    NSInteger latestFoundVersion = 0;
    NSMutableArray * objs = [[[NSMutableArray alloc] init] autorelease];
    while( TRUE )
    {
        counter++;
        
        // see if there is a class available from the start version upwards...
        Class upgradeClass = NSClassFromString( [NSString stringWithFormat:@"%@%ld",UPGRADE_CLASS_PREFIX,counter] );
        if( upgradeClass == nil )
            break;
        
        // add the upgrade
        Upgrade * upgrade = [[[upgradeClass alloc] initWithManagedObjectContext:context
                                                                     controller:self] autorelease];
        [objs addObject:upgrade];
        
        // store the latest version
        if( [upgrade versionNumber] > latestFoundVersion )
            latestFoundVersion = [upgrade versionNumber];
    }
    
    // nothing to do
    if( [objs count] == 0 )
        return;
    
    // are we new?
    if( isNew )
    {
        [config setVersion:[NSNumber numberWithInteger:latestFoundVersion]];
        [context save:&error];
        return;
    }
    
    // there is an upgrade to perform...
    // load the nib and run the modal window
    [NSBundle loadNibNamed:@"Upgrade"
                     owner:self];
    
    [label setStringValue:@"Preparing database upgrade..."];
    
    // set up the indicator
    [progressIndicator setUsesThreadedAnimation:YES];
    [progressIndicator startAnimation:nil];
    [progressIndicator setIndeterminate:YES];
    
    NSPersistentStoreCoordinator * coordinator = [context persistentStoreCoordinator];
    // start the async...
    dispatch_block_t upgradeBlock = ^{
        
        NSInteger itemsToUpgrade = 0;
        
        for( Upgrade * up in objs )
        {
            
            // create the context per request
            NSManagedObjectContext * mContext = [[[NSManagedObjectContext alloc] init] autorelease];
            [mContext setUndoManager:nil];
            [mContext setPersistentStoreCoordinator:coordinator];

            // set the context
            [up setManagedObjectContext:mContext];
            [up prefetch];
            itemsToUpgrade += [up numberOfUpgradingObjects];
        }
        
        // set the min and max on the progress indicator
        [progressIndicator setMinValue:0];
        [progressIndicator setMaxValue:itemsToUpgrade];
        [progressIndicator setIndeterminate:NO];
        
        // label
        dispatch_sync( dispatch_get_main_queue(), ^{
            [label setStringValue:@"Upgrading database..."];
        });
        
        // run the main
        for( Upgrade * up in objs )
        {
            NSLog(@"Upgrading DB to version %ld",[up versionNumber]);
            [up main];
            [up save];
            [up clean];
            [config setVersion:[NSNumber numberWithInteger:[up versionNumber]]];
            NSLog(@"Upgraded DB to version %ld",[up versionNumber]);
        }
        
        // stop the modal
        dispatch_sync( dispatch_get_main_queue(), ^{
            
            [label setStringValue:@"Cleaning up..."];
            // clean up...
            [progressIndicator setIndeterminate:YES];
            [progressIndicator startAnimation:nil];
            
            double delayInSeconds = 2.0;
            dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
            dispatch_after(popTime, dispatch_get_main_queue(), ^(void)
            {
                // set the label back
                [label setStringValue:@"Database upgrade complete."];
                
                [progressIndicator setIndeterminate:NO];
                [progressIndicator startAnimation:nil];
                
                // kill the modal
                double delayInSeconds = 2.0;
                dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
                dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
                    // abort the modal
                    [NSApp abortModal];
                });
            });
            
        });
        
    };
       
    // dispatch the async block after a delay
    double delayInSeconds = 1.0;
    dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
    dispatch_after(popTime, dispatch_get_global_queue( DISPATCH_QUEUE_PRIORITY_HIGH, 0 ), ^(void)
    {
        dispatch_async( dispatch_get_main_queue(), ^{
            
            // set the label to backup
            [label setStringValue:@"Creating database backup..."];
            
            dispatch_async( dispatch_get_global_queue( DISPATCH_QUEUE_PRIORITY_HIGH, 0 ), ^{
                
                // create backup here...
                NSURL * storeURL = [[[[context persistentStoreCoordinator] persistentStores] objectAtIndex:0] URL];
                if( [[NSFileManager defaultManager] fileExistsAtPath:[storeURL path]] )
                {
                    NSDateFormatter * dateFormatter = [[[NSDateFormatter alloc] init] autorelease];
                    [dateFormatter setDateFormat:@"yyyy-MM-dd HH-mm-ss"];
                    NSError * error = nil;
                    NSString * location = [NSString stringWithFormat:@"%@/%@.cafdb",NSUserLibraryPathWithDirectory( @"Backup/Databases" ),[dateFormatter stringFromDate:[NSDate date]]];
                    [[NSFileManager defaultManager] copyItemAtPath:[storeURL path]
                                                            toPath:location
                                                             error:&error];
                }
                
                double delayInSeconds = 2.0;
                dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
                dispatch_after(popTime, dispatch_get_current_queue(), upgradeBlock );
                
            });
            
        });
    });
    
    // stop the run loop and make it modal...basically just block the window
    while( [NSApp runModalForWindow:window] == NSRunContinuesResponse )
        continue;
    
    // save the objects
    [context save:&error];
    
    // now its done we need to store the new version number
    [window close], window = nil;
    
}

@end