root/Nuku/trunk/Controller.m

/* $Id$ */

/*
 * Copyright (c) 2000-2006 Axel Andersson
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#import "Controller.h"
#import "Settings.h"
#import "Session.h"
#import "Tutor.h"

@implementation Controller

- (id)init {
        self = [super init];
        
        _tutor = [[Tutor alloc] init];
        
        return self;
}


- (void)dealloc {
        [_tutor release];
        
        [super dealloc];
}

        

#pragma mark -

- (void)awakeFromNib {
        // --- update the settings menu from prefs
        [self updateSettings];
}



/*
        Called when the application receives a shutdown notice, i.e. the user quits.
*/

- (void)applicationWillTerminate:(NSNotification *)notification {
        [Settings setObject:[windowTutor stringWithSavedFrame]
                          forKey:kDefaultsTutorPosition];
}



/*
        Called when the tutor window is about to be closed.
*/

- (void)windowWillClose:(NSNotification *)notification {
        [Settings setObject:[windowTutor stringWithSavedFrame]
                          forKey:kDefaultsTutorPosition];

        [self resetTutor];
}



/*
        Called when the user wrote a char to the text field. Prevents more than
        3 characters from passing through.
*/

- (void)controlTextDidChange:(NSNotification *)notification {
        NSString                *string;
        
        string = [fieldKana stringValue];
        
        if([string length] > 3)
                [fieldKana setStringValue:[string substringToIndex:3]];
}



#pragma mark -


/*
        Opens the tutor window and prepares it.
*/

- (void)openTutor {
        NSArray                 *menuItems;
        NSEnumerator    *enumerator;
        NSMenuItem              *menuItem;
        NSString                *windowPosition;
        bool                    state = YES;
        
        // --- off by default
        _waitingForUser = NO;

        // --- clear all fields
        [textCorrect setStringValue:@""];
        [textAnswer setStringValue:@""];
        [fieldKana setStringValue:@""];
        [self setImageByKanaName:NULL];
        
        // --- lock down the Settings menu if we should
        if([[Settings objectForKey:kDefaultsLockSettings] boolValue])
                state = NO;
        
        [menuSettings setAutoenablesItems:NO];
        menuItems       = [menuSettings itemArray];
        enumerator      = [menuItems objectEnumerator];
        
        while((menuItem = [enumerator nextObject]))
                [menuItem setEnabled:state];
        
        // --- lock quiz/learning if we're in a limited session
        if([[Settings objectForKey:kDefaultsSession] intValue] == kDefaultsSessionLimited) {
                [Settings setObject:[NSNumber numberWithInt:kDefaultsModeQuiz]
                                  forKey:kDefaultsMode];

                [itemQuizMode setState:NSOnState];
                [itemLearningMode setState:NSOffState];

                [itemQuizMode setEnabled:NO];
                [itemLearningMode setEnabled:NO];
        }
        
        // --- select our romanisation system
        [_tutor switchRomanisationStrings:[[Settings objectForKey:kDefaultsRomanisationSystem] intValue]];
        
        // --- update the buttons according to the romanisation system
        [self updateButtonTitles];
        
        // --- update the buttons according to our Lines settings
        [self updateButtons];
        
        // --- set these to 0
        [_tutor setCorrect:0];
        [_tutor setQuestions:0];
        [self updateScore];
        
        // --- move to saved position
        windowPosition = [Settings objectForKey:kDefaultsTutorPosition];
        
        if([windowPosition isEqualTo:@""])
                [windowTutor center];
        else
                [windowTutor setFrameFromString:windowPosition];

        // --- show the window
        [windowTutor makeKeyAndOrderFront:self];

        // --- get a timestamp
        _startTime      = time(NULL);
        _stopTime       = 0;

        // --- install a timer that fires when our time is up if we're in a limited session
        if([[Settings objectForKey:kDefaultsSession] intValue] == kDefaultsSessionLimited &&
           [[Settings objectForKey:kDefaultsTimeLimit] intValue] > 0) {
                _timer = [NSTimer scheduledTimerWithTimeInterval:[[Settings objectForKey:kDefaultsTimeLimit] intValue]
                                                  target:self
                                                  selector:@selector(sessionShouldFinish)
                                                  userInfo:NULL
                                                  repeats:NO];
        }
}




/*
        Resets the tutor to its original state, possibly for a new session.
*/

- (void)resetTutor {
        NSArray                 *menuItems;
        NSEnumerator    *enumerator;
        NSMenuItem              *menuItem;

        // --- re-enable the settings menu
        menuItems               = [menuSettings itemArray];
        enumerator              = [menuItems objectEnumerator];
        
        while((menuItem = [enumerator nextObject]))
                [menuItem setEnabled:YES];

        // --- kill the timer
        if(_timer) {
                [_timer invalidate];
                
                _timer = NULL;
        }
}




- (void)sessionShouldFinish {
        // --- we don't want to do this if we've already finished
        if([sessionOutlet isDone])
                return;
                
        // --- get a timestamp
        _stopTime = time(NULL);
        _diffTime = _stopTime - _startTime;
        
        // --- close this window
        [windowTutor close];
        
        // --- mark as finished
        [sessionOutlet done];

        // --- open the next
        [sessionOutlet showReport];
}



#pragma mark -

/*
        Called when the user clicks a kana button.
*/

- (IBAction)clickKana:(NSMatrix *)sender {
        NSString                *currentKana, *clickedKana, *infoString;
        NSButton                *clickedButton;

        switch([[Settings objectForKey:kDefaultsMode] intValue]) {
                case kDefaultsModeQuiz:
                        // --- if we're waiting for the user to click the mouse and she
                        //     clicked a button, confirm this as a click
                        if(_waitingForUser) {
                                [self userConfirmed];
                                
                                return;
                        }

                        // --- update number of questions
                        [_tutor setQuestions:[_tutor getQuestions] + 1];
                        
                        // --- get the name of the selected button and the correct name
                        clickedButton   = [sender cellAtRow:[sender selectedRow] column:[sender selectedColumn]];
                        clickedKana             = [clickedButton title];
                        currentKana             = [_tutor getCurrentKanaName];
                        [_tutor setCurrentKanaName:currentKana];
                        
                        if([clickedKana isEqualToString:[_tutor getExpandedKanaName:currentKana]])
                                [self userWasCorrect:clickedKana];
                        else
                                [self userWasIncorrect:clickedKana];

                        // --- update the scoreboard
                        [self updateScore];
                        break;
                
                case kDefaultsModeLearning:
                        // --- get the name of the selected button
                        clickedButton   = [sender
                                                                cellAtRow:[sender selectedRow]
                                                                column:[sender selectedColumn]];
                        currentKana             = [clickedButton alternateTitle];

                        // --- set our internal name to it
                        [_tutor setCurrentKanaName:currentKana];
                        
                        // --- display the correct kana image
                        [self setImageByKanaName:currentKana];
                        
                        // --- and display the name of it, as we're in learning mode
                        infoString = [NSString stringWithFormat:@"'%@'",
                                                        [_tutor getExpandedKanaName:currentKana]];
                        [textCorrect setTextColor:[NSColor blackColor]];
                        [textCorrect setStringValue:infoString];
                        break;
        }
        
        // --- drop out if we're done
        if([[Settings objectForKey:kDefaultsKanaLimit] intValue] == [_tutor getQuestions]  &&
           [[Settings objectForKey:kDefaultsSession] intValue] == kDefaultsSessionLimited)
                [self sessionShouldFinish];
}



/*
        Called when the user clicks the OK button.
*/

- (IBAction)writeKana:(NSButton *)sender {
        NSString        *currentKana, *writtenKana, *infoString;
        NSArray         *keys;

        switch([[Settings objectForKey:kDefaultsMode] intValue]) {
                case kDefaultsModeQuiz:
                        // --- if we're waiting for the user to click the mouse and she
                        //     clicked a button, confirm this as a click
                        if(_waitingForUser) {
                                [self userConfirmed];
                                
                                return;
                        }

                        // --- update number of questions
                        [_tutor setQuestions:[_tutor getQuestions] + 1];
                        
                        // --- get the name of the selected button and the correct name
                        writtenKana = [fieldKana stringValue];
                        currentKana = [_tutor getCurrentKanaName];
                        [_tutor setCurrentKanaName:currentKana];
                        
                        if([writtenKana isEqualToString:[_tutor getExpandedKanaName:currentKana]])
                                [self userWasCorrect:currentKana];
                        else
                                [self userWasIncorrect:writtenKana];
                        
                        // --- update the scoreboard
                        [self updateScore];
                        break;
                
                case kDefaultsModeLearning:
                        // --- get the kana
                        writtenKana = [fieldKana stringValue];
                        keys = [[_tutor getCurrentStrings] allKeysForObject:writtenKana];
                        
                        if([keys count] > 0) {
                                currentKana = [keys objectAtIndex:0];

                                // --- set our internal name to it
                                [_tutor setCurrentKanaName:currentKana];
                                
                                // --- display the correct kana image
                                [self setImageByKanaName:currentKana];
                                
                                // --- and display the name of it, as we're in learning mode
                                infoString = [NSString stringWithFormat:@"'%@'", writtenKana];
                                [textCorrect setTextColor:[NSColor blackColor]];
                                [textCorrect setStringValue:infoString];
                        }
                        break;
        }
        
        // --- drop out if we're done
        if([[Settings objectForKey:kDefaultsKanaLimit] intValue] == [_tutor getQuestions]  &&
           [[Settings objectForKey:kDefaultsSession] intValue] == kDefaultsSessionLimited)
                [self sessionShouldFinish];
}



/*
        Increase score, tell the user she was correct, and start on a new kana.
*/

- (void)userWasCorrect:(NSString *)kana {
        NSString                *infoString, *currentKana, *outKana;

        // --- display correct message in green - according to testers,
        //     plain greenColor is a tad too light, so we darken it a bit
        outKana = [_tutor getExpandedKanaName:kana];
        infoString = [NSString stringWithFormat:NSLocalizedString(@"'%@' is correct.", @""), outKana];
        [textCorrect setTextColor:[NSColor colorWithDeviceRed:0.05 green:0.9 blue:0.05 alpha:1.0]];
        [textCorrect setStringValue:infoString];
        
        // --- this should say nothing here
        [textAnswer setStringValue:@""];

        [_tutor setCorrect:[_tutor getCorrect] + 1];
        
        // --- get a random kana name and display its image
        currentKana     = [_tutor getRandomKanaName];
        [_tutor setCurrentKanaName:currentKana];
        [self setImageByKanaName:currentKana];
}



/*
        Tell the user she was incorrect, waiting for her to confirm it if we should.
*/

- (void)userWasIncorrect:(NSString *)kana {
        NSString                *infoString, *currentKana, *outKana;
        
        // --- display incorrect message in red
        [textCorrect setTextColor:[NSColor redColor]];
        
        // --- the user may have written something that isn't even a kana name
        outKana = [_tutor getExpandedKanaName:kana];
        if(!outKana)
                outKana = kana;
        
        // --- tell the user what the correct answer should have been
        infoString = [NSString stringWithFormat:NSLocalizedString(@"The correct answer was '%@'.", @""),
                                        [_tutor getExpandedKanaName:[_tutor getCurrentKanaName]]];
        [textAnswer setStringValue:infoString];

        if([[Settings objectForKey:kDefaultsMouseDownOnIncorrect] boolValue]) {
                // --- wait for the user to confirm her mistake
                infoString = [NSString stringWithFormat:NSLocalizedString(@"'%@' is incorrect. Click to continue.", @""),
                                                outKana];
                [textCorrect setStringValue:infoString];

                // --- this will get cleared in userDidMouseDown
                _waitingForUser = YES;
        } else {
                // --- just say that it's incorrect and continue
                infoString = [NSString stringWithFormat:NSLocalizedString(@"'%@' is incorrect.", @""), outKana];
                [textCorrect setStringValue:infoString];

                // --- get a random kana name and display its image
                currentKana     = [_tutor getRandomKanaName];
                [_tutor setCurrentKanaName:currentKana];
                [self setImageByKanaName:currentKana];
        }
}



#pragma mark -

/*
        Called when the user selects "Lines To Test" from the Settings menu.
*/

- (IBAction)openLines:(id)sender {
        int                     lines;
        
        // --- get our bit field
        lines = [[Settings objectForKey:kDefaultsLines] intValue];

        // --- mark the checkboxes accordingly
        if(lines & kDefaultsLinesA)
                [linesA setState:NSOnState];
        if(lines & kDefaultsLinesBa)
                [linesBa setState:NSOnState];
        if(lines & kDefaultsLinesDa)
                [linesDa setState:NSOnState];
        if(lines & kDefaultsLinesGa)
                [linesGa setState:NSOnState];
        if(lines & kDefaultsLinesHa)
                [linesHa setState:NSOnState];
        if(lines & kDefaultsLinesKa)
                [linesKa setState:NSOnState];
        if(lines & kDefaultsLinesMa)
                [linesMa setState:NSOnState];
        if(lines & kDefaultsLinesNa)
                [linesNa setState:NSOnState];
        if(lines & kDefaultsLinesPa)
                [linesPa setState:NSOnState];
        if(lines & kDefaultsLinesRa)
                [linesRa setState:NSOnState];
        if(lines & kDefaultsLinesSa)
                [linesSa setState:NSOnState];
        if(lines & kDefaultsLinesTa)
                [linesTa setState:NSOnState];
        if(lines & kDefaultsLinesWa)
                [linesWa setState:NSOnState];
        if(lines & kDefaultsLinesYa)
                [linesYa setState:NSOnState];
        if(lines & kDefaultsLinesZa)
                [linesZa setState:NSOnState];
        
        // --- show the window
        [windowLines center];
        [windowLines makeKeyAndOrderFront:self];
}



/*
        Called when the user clicks the OK button in the Lines dialog.
*/

- (IBAction)linesOK:(NSButton *)sender {
        NSString        *currentKana;
        int                     lines = kDefaultsLinesEmpty;
        
        // --- update the bit field
        if([linesA state] == NSOnState)
                lines |= kDefaultsLinesA;
        if([linesBa state] == NSOnState)
                lines |= kDefaultsLinesBa;
        if([linesDa state] == NSOnState)
                lines |= kDefaultsLinesDa;
        if([linesGa state] == NSOnState)
                lines |= kDefaultsLinesGa;
        if([linesHa state] == NSOnState)
                lines |= kDefaultsLinesHa;
        if([linesKa state] == NSOnState)
                lines |= kDefaultsLinesKa;
        if([linesMa state] == NSOnState)
                lines |= kDefaultsLinesMa;
        if([linesNa state] == NSOnState)
                lines |= kDefaultsLinesNa;
        if([linesPa state] == NSOnState)
                lines |= kDefaultsLinesPa;
        if([linesRa state] == NSOnState)
                lines |= kDefaultsLinesRa;
        if([linesSa state] == NSOnState)
                lines |= kDefaultsLinesSa;
        if([linesTa state] == NSOnState)
                lines |= kDefaultsLinesTa;
        if([linesWa state] == NSOnState)
                lines |= kDefaultsLinesWa;
        if([linesYa state] == NSOnState)
                lines |= kDefaultsLinesYa;
        if([linesZa state] == NSOnState)
                lines |= kDefaultsLinesZa;
        
        // --- update the settings
        [Settings setObject:[NSNumber numberWithInt:lines] forKey:kDefaultsLines];
        
        // --- re-initiate the currentStrings dict so we can starting
        //     reducing from from a fresh one
        [_tutor switchRomanisationStrings:
                [[Settings objectForKey:kDefaultsRomanisationSystem] intValue]];
        
        // --- update the Tutor window
        [self updateButtons];
        
        if([[Settings objectForKey:kDefaultsMode] intValue] == kDefaultsModeQuiz) {
                // --- we might have an old kana in the well
                currentKana     = [_tutor getRandomKanaName];
                [_tutor setCurrentKanaName:currentKana];
                [self setImageByKanaName:currentKana];
        }
        
        // --- and close
        [windowLines close];
}



/*
        Called when the user click the "Select All" button in the Lines dialog.
*/

- (IBAction)linesSelectAll:(NSButton *)sender {
        [linesA setState:NSOnState];
        [linesBa setState:NSOnState];
        [linesDa setState:NSOnState];
        [linesGa setState:NSOnState];
        [linesHa setState:NSOnState];
        [linesKa setState:NSOnState];
        [linesMa setState:NSOnState];
        [linesNa setState:NSOnState];
        [linesPa setState:NSOnState];
        [linesRa setState:NSOnState];
        [linesSa setState:NSOnState];
        [linesTa setState:NSOnState];
        [linesWa setState:NSOnState];
        [linesYa setState:NSOnState];
        [linesZa setState:NSOnState];
}





#pragma mark -

/*
        Set up a new quiz/learning.
*/

- (void)start {
        // --- go nuku go
        switch([[Settings objectForKey:kDefaultsMode] intValue]) {
                case kDefaultsModeQuiz:
                        [self startNewQuiz];
                        break;
                
                case kDefaultsModeLearning:
                        [self startNewLearning];
                        break;
        }
}



/*
        Set up a new quiz, zero out the score table and kick it off.
*/

- (void)startNewQuiz {
        NSString                *currentKana;
        
        [windowTutor setTitle:NSLocalizedString(@"Nuku - Quiz Mode", @"")];

        // --- clear all fields
        [textCorrect setStringValue:@""];
        [textAnswer setStringValue:@""];
        [fieldKana setStringValue:@""];
        
        // --- set these to 0
        [_tutor setCorrect:0];
        [_tutor setQuestions:0];
        
        // --- display the score
        [self updateScore];

        // --- get a random kana and display it, kicking off the quiz
        currentKana = [_tutor getRandomKanaName];
        [_tutor setCurrentKanaName:currentKana];
        [self setImageByKanaName:currentKana];
}



/*
        Prepare for learning mode, clear score and image out.
*/

- (void)startNewLearning {
        [windowTutor setTitle:NSLocalizedString(@"Nuku - Learning Mode", @"")];

        // --- clear all fields
        [textCorrect setStringValue:@""];
        [textAnswer setStringValue:@""];
        [fieldKana setStringValue:@""];
        [self setImageByKanaName:NULL];
        
        // --- set these to 0
        [_tutor setCorrect:0];
        [_tutor setQuestions:0];
        
        // --- display the score
        [self updateScore];
}



#pragma mark -

/*
        Updates the Settings menu from prefs.
*/

- (void)updateSettings {
        // --- set up initial kana type
        switch([[Settings objectForKey:kDefaultsKanaType] intValue]) {
                case kDefaultsKanaTypeHiragana:
                        [itemHiragana setState:NSOnState];
                        break;
                
                case kDefaultsKanaTypeKatakana:
                        [itemKatakana setState:NSOnState];
                        break;
                
                case kDefaultsKanaTypeMixed:
                        [itemMixed setState:NSOnState];
                        break;
        }
        
        // --- set up initial romanisation system
        switch([[Settings objectForKey:kDefaultsRomanisationSystem] intValue]) {
                case kDefaultsRomanisationSystemHepburn:
                        [itemHepburn setState:NSOnState];
                        break;
                
                case kDefaultsRomanisationSystemKunreiSiki:
                        [itemKunreiSiki setState:NSOnState];
                        break;
                
                case kDefaultsRomanisationSystemNihonSiki:
                        [itemNihonSiki setState:NSOnState];
                        break;
        }
        
        // --- set up initial mode
        switch([[Settings objectForKey:kDefaultsMode] intValue]) {
                case kDefaultsModeQuiz:
                        [itemQuizMode setState:NSOnState];
                        break;
                
                case kDefaultsModeLearning:
                        [itemLearningMode setState:NSOnState];
                        break;
        }
}



/*
        Update the scoreboard and set the scores accordingly.
*/

- (void)updateScore {
        int                             correct, questions;
        float                   percent;
        
        correct                 = [_tutor getCorrect];
        questions               = [_tutor getQuestions];
        
        if(questions == 0)
                percent         = 0;
        else
                percent         = ((float) correct / (float) questions) * 100;

        [textScore setStringValue:[NSString stringWithFormat:@"%d/%d", correct, questions]];
        [textPercent setFloatValue:percent];
}



/*
        Update the buttons that have different names between the romanisation systems.
*/

- (void)updateButtonTitles {
        [kanaSi setTitle:[_tutor getExpandedKanaName:[kanaSi alternateTitle]]];
        [kanaZi setTitle:[_tutor getExpandedKanaName:[kanaZi alternateTitle]]];
        [kanaTi setTitle:[_tutor getExpandedKanaName:[kanaTi alternateTitle]]];
        [kanaTu setTitle:[_tutor getExpandedKanaName:[kanaTu alternateTitle]]];
        [kanaDi setTitle:[_tutor getExpandedKanaName:[kanaDi alternateTitle]]];
        [kanaDu setTitle:[_tutor getExpandedKanaName:[kanaDu alternateTitle]]];
        [kanaHu setTitle:[_tutor getExpandedKanaName:[kanaHu alternateTitle]]];
}



/*
        Update the buttons according to the Lines settings.
*/

- (void)updateButtons {
        int                             i, j, lines;
        NSButton                *button;
        
        // --- get our bit field
        lines                   = [[Settings objectForKey:kDefaultsLines] intValue];
        
        for(i = 0; i < 15; i++) {
                for(j = 0; j < 5; j++) {
                        button = [buttonsKana cellAtRow:j column:i];
                        
                        // --- we store the bit mask in the tag of the button
                        if(lines & [button tag])
                                [button setEnabled: YES];
                        else {
                                [_tutor reduceRomanisationStrings:[button alternateTitle]];
                                [button setEnabled: NO];
                        }
                }
        }
}



#pragma mark -

/*
        Set the image well to display the kana provided.
*/

- (void)setImageByKanaName:(NSString *)kanaName {
        [imageKana setImage:[_tutor getKanaImageByName:kanaName]];
}



/*
        Get a new random kana and clear the waitingForUser flag to determine
        that the user has confirmed.
*/

- (void)userConfirmed {
        NSString                *currentKana;
        
        if(_waitingForUser) {
                // --- clear these
                [textCorrect setStringValue:@""];
                [textAnswer setStringValue:@""];
                
                // --- get a random kana name and display its image
                currentKana     = [_tutor getRandomKanaName];
                [_tutor setCurrentKanaName:currentKana];
                [self setImageByKanaName:currentKana];
                
                _waitingForUser = NO;
        }
}



#pragma mark -

/*
        Called when user switches between quiz and learning mode.
*/

- (IBAction)changeMode:(id)sender {
        // --- store value in settings for later retrieval
        [Settings setObject:[NSNumber numberWithInt:[sender tag]]
                          forKey:kDefaultsMode];
        
        // --- turn off everyone, then turn on the sender
        [itemQuizMode setState:NSOffState];
        [itemLearningMode setState:NSOffState];
        [sender setState:NSOnState];

        switch([[Settings objectForKey:kDefaultsMode] intValue]) {
                case kDefaultsModeQuiz:
                        [self startNewQuiz];
                        break;
                
                case kDefaultsModeLearning:
                        [self startNewLearning];
                        break;
        }
}



/*
        Called when user changes kana type.
*/

- (IBAction)changeKanaType:(id)sender {
        // --- store value in settings for later retrieval
        [Settings setObject:[NSNumber numberWithInt:[sender tag]]
                          forKey:kDefaultsKanaType];
        
        // --- turn off everyone, then turn on the sender
        [itemHiragana setState:NSOffState];
        [itemKatakana setState:NSOffState];
        [itemMixed setState:NSOffState];
        [sender setState:NSOnState];
        
        // --- update the image
        [self setImageByKanaName:[_tutor getCurrentKanaName]];
}



/*
        Called when user switches romanisation system.
*/

- (IBAction)changeRomanisationSystem:(id)sender {
        NSString                *currentKana, *infoString;
        
        // --- store value in settings for later retrieval
        [Settings setObject:[NSNumber numberWithInt:[sender tag]]
                          forKey:kDefaultsRomanisationSystem];

        // turn off everyone, then turn on the sender
        [itemHepburn setState:NSOffState];
        [itemKunreiSiki setState:NSOffState];
        [itemNihonSiki setState:NSOffState];
        [sender setState:NSOnState];
        
        // --- update the current strings
        [_tutor switchRomanisationStrings:[sender tag]];
        
        // --- update the current display if we're in learning mode
        currentKana = [_tutor getCurrentKanaName];

        if([[Settings objectForKey:kDefaultsMode] intValue] == kDefaultsModeLearning &&
           currentKana != NULL) {
                // --- 'kana'
                infoString = [NSString stringWithFormat:@"'%@'",
                        [_tutor getExpandedKanaName:currentKana]];
                [textCorrect setStringValue:infoString];
        }
        
        // --- update the button titles
        [self updateButtonTitles];
        
        // --- update the buttons
        [self updateButtons];
}



#pragma mark -

/*
        Get the number of questions.
*/

- (int)getQuestions {
        return [_tutor getQuestions];
}



/*
        Get the number of corrects.
*/

- (int)getCorrect {
        return [_tutor getCorrect];
}



/*
        Get the elapsed time.
*/

- (int)getTime {
        return _diffTime;
}


@end