/*

 Copyright (C) 2018 Apple Inc. All Rights Reserved.

 See LICENSE.txt for this sample’s licensing information

 Abstract:

 View controller for the initial screen.  Manages creating the Quiz  

  and displaying the user's highest score.

 */

#import "MainMenuViewController.h"

#import "Quiz.h"

#import "QuestionViewController.h"

#import "ResultsViewController.h"

@interface MainMenuViewController () <UITableViewDataSource, UITabBarControllerDelegate>

@property (nonatomic, weak) IBOutlet UITableView *tableView;

@property (readwrite) float highScore;

@end

@implementation MainMenuViewController

//| ----------------------------------------------------------------------------

- (void)viewDidLoad

{

    [super viewDidLoad];

    // match the background color to the status bar

    [[UINavigationBar appearance] setTranslucent:NO];

    // No highscrore when the view first loads.

    self.highScore = -1.0f;

}

//| ----------------------------------------------------------------------------

- (void)viewWillAppear:(BOOL)animated

{

    [super viewWillAppear:animated];

    [self.tableView reloadData];

}

//| ----------------------------------------------------------------------------

//  This method will be called when the 'Begin' button is tapped.

//

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender

{

    // Set the quiz of the destination view controller.

    // In a navigation stack the segue.destinationViewController is instantiated.

    // However for a custom segue it is not, so we will set the quiz in the segue's -perform method.

    if ([segue.destinationViewController isKindOfClass:[UINavigationController class]])

    {

        [Quiz setQuizOnQuestionViewController:segue.destinationViewController.childViewControllers.firstObject];

    }

}

//| ----------------------------------------------------------------------------

//! Unwinds from the ResultsViewController back to the MainMenuViewController

//! when the user taps the 'Return to the Home Screen' button.

//

//  This is an unwind action.  Note that the sender parameter is a

//  'UIStoryboardSegue*' instead of the usual 'id'.  Like all unwind actions,

//  this method is invoked early in the unwind process, before the visual

//  transition.  Note that the receiver of this method is the

//  destinationViewController of the segue.  Your view controller should use

//  this callback to retrieve information from the sourceViewController.  Used

//  properly, this method can replace existing delegation techniques for

//  passing information from a detail view controller to a previous view

//  controller in the navigation hierarchy.

//

- (IBAction)exitToHomeScreen:(UIStoryboardSegue *)unwindSegue

{

    // Retrieve the score from the ResultsViewController and update the high

    // score.

    ResultsViewController *resultVC = (ResultsViewController*)unwindSegue.sourceViewController;

    self.highScore = MAX(resultVC.currentQuiz.percentageScore, self.highScore);

}

#pragma mark -

#pragma mark UITableViewDatasource

//| ----------------------------------------------------------------------------

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView

{

    // If there is a highscore to display, there are three sections.  Else,

    // there are two sections.

    return (self.highScore > -1.0f) ? 3 : 2;

}

//| ----------------------------------------------------------------------------

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section

{

    // There is only one row per section.

    return 1;

}

//| ----------------------------------------------------------------------------

- (UITableViewCell*)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath

{

    UITableViewCell *cell;

    if (indexPath.section == 0)

        cell = [tableView dequeueReusableCellWithIdentifier:@"Instructions"];

    else if (indexPath.section == 1 && tableView.numberOfSections == 3)

    // If there are three setions being displayed, the second row shows the

    // highscore.

    {

        cell = [tableView dequeueReusableCellWithIdentifier:@"Score"];

        cell.textLabel.text = [NSString stringWithFormat:@"Your best recorded score is %.0f%%", self.highScore * 100];

    }

    else

        // Last section is always the Begin button.

        cell = [tableView dequeueReusableCellWithIdentifier:@"Begin"];

    return cell;

}

#pragma mark -

#pragma mark UITableViewDelegate

//| ----------------------------------------------------------------------------

//  This delegate method is implemented because the height of the

//  instructions cell will need to change depending on the height required to

//  display the instruction text.  As the device rotates this will change.

//

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath

{

    if (indexPath.section == 0)

    // Instructions cell

    {

        UITableViewCell *instructionsCell = [tableView dequeueReusableCellWithIdentifier:@"Instructions"];

        UILabel *instructionsLabel = instructionsCell.textLabel;

        // Use the -boundingRectWithSize:options:attributes:context: method of NSString to

        // determine the required height of the instructions cell in order

        // to display the instructions without cutting off any of the text.

        // The width must be constrained to the width of the table view minus the

        // left and right margin of a grouped style cell.

        // Unfortunately, there is no way to lookup exactly what that margin is,

        // so it must be hardcoded.

        // The height is left unconstrained.

        CGSize constrainingSize = CGSizeMake(tableView.bounds.size.width - 40*2, MAXFLOAT);

        return ceill([instructionsLabel.text boundingRectWithSize:constrainingSize options:NSStringDrawingUsesLineFragmentOrigin attributes:nil context:nil].size.height + 40);

    }

    return tableView.rowHeight;

}

@end