//
//  UIViewControllerDateRangeEditor.m
//  UIViewControllerDateRangeEditor
//

#import "UIViewControllerDateRangeEditor.h"

@interface UIViewControllerDateRangeEditor ( PrivateMethods )

- (NSDateFormatter*) createDateFormatter;

- (NSTimeInterval) limitTimeInterval:(NSTimeInterval)_timeValue;

- (NSString*) stringFromDateTimeInterval:(NSTimeInterval)_interval;

- (void) selectButtonHold:(id)sender;

@end


@implementation UIViewControllerDateRangeEditor

#pragma mark ---------------------------------------------------------
#pragma mark === Properties  ===
#pragma mark ---------------------------------------------------------

-(NSTimeInterval) startTimeInterval
{
	return startTimeInterval;
}
- (void) setStartTimeInterval:(NSTimeInterval)_timeValue
{
	startTimeInterval = _timeValue;
	
	// setup the display
	[startDate setText:[self stringFromDateTimeInterval:startTimeInterval]];
}

-(NSTimeInterval) endTimeInterval
{
	return endTimeInterval;
}
- (void) setEndTimeInterval:(NSTimeInterval)_timeValue
{
	endTimeInterval = _timeValue;
	
	// setup the display
	[endDate setText:[self stringFromDateTimeInterval:endTimeInterval]];
}

@synthesize minTimeInterval;
@synthesize maxTimeInterval;
@synthesize savePressed;

#pragma mark ---------------------------------------------------------
#pragma mark === End Properties  ===
#pragma mark ---------------------------------------------------------

#pragma mark ---------------------------------------------------------
#pragma mark === Constructor / Destructor Functions  ===
#pragma mark ---------------------------------------------------------

// -------------------------------------------------------------------
// Initialisation
// -------------------------------------------------------------------
- (id)initWithCoder:(NSCoder*)coder 
{
	if (self = [super initWithCoder:coder]) 
	{
		dateFormatter = [self createDateFormatter];
		
		[self reset];
	}
	return self;
}

// -------------------------------------------------------------------
// Initialisation
// -------------------------------------------------------------------
- (id) initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil 
{
    if (self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]) 
	{
		dateFormatter = [self createDateFormatter];
		
		[self reset];
    }
    return self;
}

// -------------------------------------------------------------------
// dealloc
// -------------------------------------------------------------------
- (void) dealloc
{	
	[leftBarButton release];
	[rightBarButton release];
	
	[startLabel release];
	[startDate release];
	
	[endLabel release];
	[endDate release];
	
	[buttonStart release];
	[buttonSelected release];
	[buttonImage release];
	
	[datePicker release];
	
	[normalColor release];
	[highlightColor release];
	
	[dateFormatter release];
	
    [super dealloc];
}

#pragma mark ---------------------------------------------------------
#pragma mark === End Constructor / Destructor Functions  ===
#pragma mark ---------------------------------------------------------

#pragma mark ---------------------------------------------------------
#pragma mark === View Functions  ===
#pragma mark ---------------------------------------------------------

// -------------------------------------------------------------------
// view did load
// -------------------------------------------------------------------
- (void) viewDidLoad 
{
	[super viewDidLoad];
	
	// Setup the navigation bar
	self.navigationItem.leftBarButtonItem = leftBarButton;
	self.navigationItem.rightBarButtonItem = rightBarButton;
	
	// grab the start date colors
	if ( normalColor == nil )
		normalColor = [[startDate textColor] retain];
	if ( highlightColor == nil )
		highlightColor = [[startDate highlightedTextColor] retain];
}

// -------------------------------------------------------------------
// view is about to appear
// -------------------------------------------------------------------
- (void) viewWillAppear:(BOOL)animated 
{	
	[super viewWillAppear:animated];
	
	// save has not been pressed
	savePressed = FALSE;
	
	// limit the start and end dates to be within the min and max values
	self.startTimeInterval	= [self limitTimeInterval:self.startTimeInterval];
	self.endTimeInterval	= [self limitTimeInterval:self.endTimeInterval];
	
	// set the date in the picker
	[datePicker setDate:[NSDate dateWithTimeIntervalSince1970:startTimeInterval] animated:FALSE];
	
	// always start editing the start date
	[self selectStartDate:buttonStart];
	
	// set the min and max date values
	[datePicker setMinimumDate:[NSDate dateWithTimeIntervalSince1970:minTimeInterval]];
	[datePicker setMaximumDate:[NSDate dateWithTimeIntervalSince1970:maxTimeInterval]];
}

// -------------------------------------------------------------------
// view is did to disappear
// -------------------------------------------------------------------
- (void) viewDidDisappear:(BOOL)animated
{
	[super viewWillDisappear:animated];
	
	if ( delayReset )
	{
		[self reset];
	}
	
	// ----------------------------------------------
	// reset the button back to it's normal state.
	// ----------------------------------------------
	[buttonSelected setBackgroundImage:buttonImage forState:UIControlStateNormal];
	[buttonSelected setSelected:FALSE];
	[buttonImage release];
	[buttonSelected release];
	buttonImage = nil;
	buttonSelected = nil;
	// ----------------------------------------------
}

#pragma mark ---------------------------------------------------------
#pragma mark === View Functions  ===
#pragma mark ---------------------------------------------------------

#pragma mark ---------------------------------------------------------
#pragma mark === Public Functions  ===
#pragma mark ---------------------------------------------------------

// -------------------------------------------------------------------
// reset the date value to the current date
// -------------------------------------------------------------------
- (void) reset
{
	if ( [self.view superview] )
	{
		delayReset		= TRUE;
	}
	else
	{
		savePressed				= FALSE;
		editingStartDate		= TRUE;
		
		self.startTimeInterval	= [[NSDate date] timeIntervalSince1970];
		self.endTimeInterval	= [[NSDate date] timeIntervalSince1970] + ( 60  * 60 * 48 ); // add 48 hours
		self.minTimeInterval	= [[NSDate distantPast] timeIntervalSince1970];
		self.maxTimeInterval	= [[NSDate distantFuture] timeIntervalSince1970];
	}
}

// -------------------------------------------------------------------
// cancel button has been pressed
// -------------------------------------------------------------------
- (IBAction) cancel:(id)sender 
{	
    // cancel edits	
	if ( [self.navigationController.viewControllers count] > 1 )
	{
		[self.navigationController popViewControllerAnimated:YES];
	}
	else
	{	
		[self.navigationController dismissModalViewControllerAnimated:YES];
	}
}

// -------------------------------------------------------------------
// save button has been pressed
// -------------------------------------------------------------------
- (IBAction)save:(id)sender 
{	
	// is the date range unacceptiable
	if ( startTimeInterval > endTimeInterval )
	{
		NSString * titleString   = @"Problem!";
		NSString * messageString = @"Choose an end date that is after the start date please.";
		NSString * buttonString  = @"OK";
		
		UIAlertView* alertView = [[UIAlertView alloc] initWithTitle:titleString 
															message:messageString 
														   delegate:nil 
												  cancelButtonTitle:buttonString 
												  otherButtonTitles:nil];
		[alertView show];
		[alertView release];
	}
	else
	{
		// save has been pressed
		savePressed = TRUE;
		[self cancel:sender];
	}
}

// -------------------------------------------------------------------
// date picker value has changed
// -------------------------------------------------------------------
- (IBAction) dateChanged:(id)sender 
{
	NSTimeInterval newTimeInterval = [datePicker.date timeIntervalSince1970];
	
	if ( editingStartDate )
	{
		self.startTimeInterval	= newTimeInterval;
	}
	else 
	{
		self.endTimeInterval	= newTimeInterval;
	}
	
	// indicate that there is an error
	if ( startTimeInterval > endTimeInterval )
	{
		[startDate setTextColor:[UIColor redColor]];
		[startDate setHighlightedTextColor:[UIColor redColor]];
	}
	else 
	{
		[startDate setTextColor:normalColor];
		[startDate setHighlightedTextColor:highlightColor];
	}
	
}

// -------------------------------------------------------------------
// select the start date
// -------------------------------------------------------------------
- (IBAction) selectStartDate:(id)sender
{
	[self selectButtonHold:sender];
	
	editingStartDate = TRUE;
	[datePicker setDate:[NSDate dateWithTimeIntervalSince1970:startTimeInterval] animated:TRUE];
	
	[startLabel		setHighlighted:TRUE];
	[startDate		setHighlighted:TRUE];
	
	[endLabel		setHighlighted:FALSE];
	[endDate		setHighlighted:FALSE];
}

// -------------------------------------------------------------------
// select the end date
// -------------------------------------------------------------------
- (IBAction) selectEndDate:(id)sender
{
	[self selectButtonHold:sender];
	
	editingStartDate = FALSE;
	[datePicker setDate:[NSDate dateWithTimeIntervalSince1970:endTimeInterval] animated:TRUE];
	
	[startLabel		setHighlighted:FALSE];
	[startDate		setHighlighted:FALSE];
	
	[endLabel		setHighlighted:TRUE];
	[endDate		setHighlighted:TRUE];
}

#pragma mark ---------------------------------------------------------
#pragma mark === End Public Functions  ===
#pragma mark ---------------------------------------------------------

#pragma mark ---------------------------------------------------------
#pragma mark === Privte Functions  ===
#pragma mark ---------------------------------------------------------

// -------------------------------------------------------------------
// create the date formatter
// -------------------------------------------------------------------
- (NSDateFormatter*) createDateFormatter
{
	NSDateFormatter * formatter = [[NSDateFormatter alloc] init];
	
	// set the fromatter to be medium style “Nov 23, 1937”
	[formatter setDateStyle:NSDateFormatterMediumStyle];
	[formatter setTimeStyle:NSDateFormatterShortStyle];
	
	// set the formatter to provide a localized version.
	// “Nov 23, 1937” US to UK would be “23 Nov, 1937”
	[formatter setLocale:[NSLocale currentLocale]];
	
	return formatter;
}

// -------------------------------------------------------------------
// limit the time interval
// -------------------------------------------------------------------
- (NSTimeInterval) limitTimeInterval:(NSTimeInterval)_timeValue
{
	if ( _timeValue < minTimeInterval )
	{
		_timeValue = minTimeInterval;
	}
	else if ( _timeValue > maxTimeInterval )
	{
		_timeValue = maxTimeInterval;
	}
	
	return _timeValue;
}

// -------------------------------------------------------------------
// Convert a Time interval to a date string
// -------------------------------------------------------------------
- (NSString*) stringFromDateTimeInterval:(NSTimeInterval)_interval
{	
	NSDate * date = [NSDate dateWithTimeIntervalSince1970:_interval];
	
	if ( ( [date compare:[NSDate distantPast]] != NSOrderedSame ) &&
		( [date compare:[NSDate distantFuture]] != NSOrderedSame ) )
	{
		return [dateFormatter stringFromDate:date];
	}
	return nil;
}

// -------------------------------------------------------------------
// select and hold the button so it looks like it's highlighted
// -------------------------------------------------------------------
- (void) selectButtonHold:(id)sender
{
	// This will grab the highlight image and
	// replace the normal image so the button
	// looks like it's still on.
	//
	// Note : you can use the Selected property
	//        but it sometimes flickers.
	if ( [sender isKindOfClass:[UIButton class]] )
	{
		// ----------------------------------------------
		// reset the button back to it's normal state.
		// ----------------------------------------------
		[buttonSelected setBackgroundImage:buttonImage forState:UIControlStateNormal];
		[buttonSelected setSelected:FALSE];
		[buttonImage release];
		[buttonSelected release];
		// ----------------------------------------------
		
		// ----------------------------------------------
		// update the next button state
		// ----------------------------------------------
		buttonSelected = [sender retain];
		buttonImage    = [[buttonSelected backgroundImageForState:UIControlStateNormal] retain];
		[buttonSelected setBackgroundImage:[buttonSelected backgroundImageForState:UIControlStateHighlighted] forState:UIControlStateNormal];
		[buttonSelected setSelected:TRUE];
		// ----------------------------------------------
	}
}

#pragma mark ---------------------------------------------------------
#pragma mark === End Privte Functions  ===
#pragma mark ---------------------------------------------------------

@end