//

// SlackTextViewController

// https://github.com/slackhq/SlackTextViewController

//

// Copyright 2014-2016 Slack Technologies, Inc.

// Licence: MIT-Licence

//

#import "SLKTypingIndicatorView.h"

#import "UIView+SLKAdditions.h"

#import "SLKUIConstants.h"

#define SLKTypingIndicatorViewIdentifier [NSString stringWithFormat:@"%@.%@", SLKTextViewControllerDomain, NSStringFromClass([self class])]

@interface SLKTypingIndicatorView ()

// The text label used to display the typing indicator content.

@property (nonatomic, strong) UILabel *textLabel;

@property (nonatomic, strong) NSMutableArray *usernames;

@property (nonatomic, strong) NSMutableArray *timers;

// Auto-Layout margin constraints used for updating their constants

@property (nonatomic, strong) NSLayoutConstraint *leftContraint;

@property (nonatomic, strong) NSLayoutConstraint *rightContraint;

@end

@implementation SLKTypingIndicatorView

@synthesize visible = _visible;

#pragma mark - Initializer

- (id)init

{

if (self = [super init]) {

[self slk_commonInit];

}

return self;

}

- (instancetype)initWithCoder:(NSCoder *)coder

{

if (self = [super initWithCoder:coder]) {

[self slk_commonInit];

}

return self;

}

- (void)slk_commonInit

{

self.backgroundColor = [UIColor whiteColor];

self.interval = 6.0;

self.canResignByTouch = NO;

self.usernames = [NSMutableArray new];

self.timers = [NSMutableArray new];

self.textColor = [UIColor grayColor];

self.textFont = [UIFont systemFontOfSize:12.0];

self.highlightFont = [UIFont boldSystemFontOfSize:12.0];

self.contentInset = UIEdgeInsetsMake(10.0, 40.0, 10.0, 10.0);

[self addSubview:self.textLabel];

[self slk_setupConstraints];

}

#pragma mark - SLKTypingIndicatorProtocol

- (void)setVisible:(BOOL)visible

{

// Skip when updating the same value, specially to avoid inovking KVO unnecessary

if (self.isVisible == visible) {

return;

}

// Required implementation for key-value observer compliance

[self willChangeValueForKey:NSStringFromSelector(@selector(isVisible))];

_visible = visible;

if (!visible) {

[self slk_invalidateTimers];

}

// Required implementation for key-value observer compliance

[self didChangeValueForKey:NSStringFromSelector(@selector(isVisible))];

}

- (void)dismissIndicator

{

if (self.isVisible) {

self.visible = NO;

}

}

#pragma mark - Getters

- (UILabel *)textLabel

{

if (!_textLabel) {

_textLabel = [UILabel new];

_textLabel.translatesAutoresizingMaskIntoConstraints = NO;

_textLabel.backgroundColor = [UIColor clearColor];

_textLabel.contentMode = UIViewContentModeTopLeft;

_textLabel.userInteractionEnabled = NO;

}

return _textLabel;

}

- (NSAttributedString *)attributedString

{

if (self.usernames.count == 0) {

return nil;

}

NSString *text = @"";

NSString *firstObject = [self.usernames firstObject];

NSString *lastObject = [self.usernames lastObject];

if (self.usernames.count == 1) {

text = [NSString stringWithFormat:NSLocalizedString(@"%@ is typing", nil), firstObject];

}

else if (self.usernames.count == 2) {

text = [NSString stringWithFormat:NSLocalizedString(@"%@ & %@ are typing", nil), firstObject, lastObject];

}

else if (self.usernames.count > 2) {

text = NSLocalizedString(@"Several people are typing", nil);

}

NSMutableParagraphStyle *style = [[NSMutableParagraphStyle alloc] init];

style.alignment = NSTextAlignmentLeft;

style.lineBreakMode = NSLineBreakByTruncatingTail;

style.minimumLineHeight = 10.0;

NSDictionary *attributes = @{NSFontAttributeName: self.textFont,

NSForegroundColorAttributeName: self.textColor,

NSParagraphStyleAttributeName: style,

};

NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];

if (self.usernames.count <= 2) {

[attributedString addAttribute:NSFontAttributeName value:self.highlightFont range:[text rangeOfString:firstObject]];

[attributedString addAttribute:NSFontAttributeName value:self.highlightFont range:[text rangeOfString:lastObject]];

}

return attributedString;

}

- (CGSize)intrinsicContentSize

{

return CGSizeMake(UIViewNoIntrinsicMetric, [self height]);

}

- (CGFloat)height

{

CGFloat height = self.textFont.lineHeight;

height += self.contentInset.top;

height += self.contentInset.bottom;

return height;

}

#pragma mark - Setters

- (void)setContentInset:(UIEdgeInsets)insets

{

if (UIEdgeInsetsEqualToEdgeInsets(self.contentInset, insets)) {

return;

}

if (UIEdgeInsetsEqualToEdgeInsets(self.contentInset, UIEdgeInsetsZero)) {

_contentInset = insets;

return;

}

_contentInset = insets;

[self slk_updateConstraintConstants];

}

- (void)setHidden:(BOOL)hidden

{

if (self.isHidden == hidden) {

return;

}

if (hidden) {

[self slk_prepareForReuse];

}

[super setHidden:hidden];

}

#pragma mark - Public Methods

- (void)insertUsername:(NSString *)username;

{

if (!username) {

return;

}

BOOL isShowing = [self.usernames containsObject:username];

if (_interval > 0.0) {

if (isShowing) {

NSTimer *timer = [self slk_timerWithIdentifier:username];

[self slk_invalidateTimer:timer];

}

NSTimer *timer = [NSTimer timerWithTimeInterval:_interval target:self selector:@selector(slk_shouldRemoveUsername:) userInfo:@{SLKTypingIndicatorViewIdentifier: username} repeats:NO];

[[NSRunLoop currentRunLoop] addTimer:timer forMode:NSDefaultRunLoopMode];

[self.timers addObject:timer];

}

if (isShowing) {

return;

}

[self.usernames addObject:username];

NSAttributedString *attributedString = [self attributedString];

self.textLabel.attributedText = attributedString;

self.visible = YES;

}

- (void)removeUsername:(NSString *)username

{

if (!username || ![self.usernames containsObject:username]) {

return;

}

[self.usernames removeObject:username];

if (self.usernames.count > 0) {

self.textLabel.attributedText = [self attributedString];

}

else {

self.visible = NO;

}

}

#pragma mark - Private Methods

- (void)slk_shouldRemoveUsername:(NSTimer *)timer

{

NSString *identifier = [timer.userInfo objectForKey:SLKTypingIndicatorViewIdentifier];

[self removeUsername:identifier];

[self slk_invalidateTimer:timer];

}

- (NSTimer *)slk_timerWithIdentifier:(NSString *)identifier

{

for (NSTimer *timer in self.timers) {

if ([identifier isEqualToString:[timer.userInfo objectForKey:SLKTypingIndicatorViewIdentifier]]) {

return timer;

}

}

return nil;

}

- (void)slk_invalidateTimer:(NSTimer *)timer

{

if (timer) {

[timer invalidate];

[self.timers removeObject:timer];

timer = nil;

}

}

- (void)slk_invalidateTimers

{

for (NSTimer *timer in self.timers) {

[timer invalidate];

}

[self.timers removeAllObjects];

}

- (void)slk_prepareForReuse

{

[self slk_invalidateTimers];

self.textLabel.text = nil;

[self.usernames removeAllObjects];

}

- (void)slk_setupConstraints

{

NSDictionary *views = @{@"textLabel": self.textLabel};

[self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|[textLabel]|" options:0 metrics:nil views:views]];

[self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|-(0)-[textLabel]-(0@750)-|" options:0 metrics:nil views:views]];

self.leftContraint = [[self slk_constraintsForAttribute:NSLayoutAttributeLeading] firstObject];

self.rightContraint = [[self slk_constraintsForAttribute:NSLayoutAttributeTrailing] firstObject];

[self slk_updateConstraintConstants];

}

- (void)slk_updateConstraintConstants

{

self.leftContraint.constant = self.contentInset.left;

self.rightContraint.constant = self.contentInset.right;

}

#pragma mark - Hit Testing

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event

{

[super touchesBegan:touches withEvent:event];

}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event

{

[super touchesEnded:touches withEvent:event];

if (self.canResignByTouch) {

[self dismissIndicator];

}

}

#pragma mark - Lifeterm

- (void)dealloc

{

[self slk_prepareForReuse];

_textLabel = nil;

_usernames = nil;

_timers = nil;

}

@end