Signal-iOS/SignalMessaging/utils/OWSContactAvatarBuilder.m

//
//  Copyright (c) 2021 Open Whisper Systems. All rights reserved.
//

#import "OWSContactAvatarBuilder.h"
#import "OWSContactsManager.h"
#import "TSContactThread.h"
#import "TSGroupThread.h"
#import "TSThread.h"
#import "UIFont+OWS.h"
#import <SignalMessaging/SignalMessaging-Swift.h>
#import <SignalServiceKit/SSKEnvironment.h>

NS_ASSUME_NONNULL_BEGIN

@interface OWSContactAvatarBuilder ()

@property (nonatomic, readonly, nullable) SignalServiceAddress *address;
@property (nonatomic, readonly, nullable) NSPersonNameComponents *contactNameComponents;
@property (nonatomic, readonly) ConversationColorName colorName;
@property (nonatomic, readonly) NSUInteger diameter;

@end

@implementation OWSContactAvatarBuilder

#pragma mark - Dependencies

- (OWSContactsManager *)contactsManager
{
    return (OWSContactsManager *)SSKEnvironment.shared.contactsManager;
}

- (SDSDatabaseStorage *)databaseStorage
{
    return SDSDatabaseStorage.shared;
}

#pragma mark - Initializers

- (instancetype)initWithAddress:(nullable SignalServiceAddress *)address
                 nameComponents:(nullable NSPersonNameComponents *)nameComponents
                      colorName:(ConversationColorName)colorName
                       diameter:(NSUInteger)diameter
{
    self = [super init];
    if (!self) {
        return self;
    }

    OWSAssertDebug(colorName.length > 0);

    _address = address;
    _contactNameComponents = nameComponents;
    _colorName = colorName;
    _diameter = diameter;

    return self;
}

- (instancetype)initWithAddress:(SignalServiceAddress *)address
                      colorName:(ConversationColorName)colorName
                       diameter:(NSUInteger)diameter
{
    // Components for avatar initials.
    __block NSPersonNameComponents *_Nullable nameComponents;
    [self.databaseStorage uiReadWithBlock:^(SDSAnyReadTransaction *transaction) {
        nameComponents = [self.contactsManager nameComponentsForAddress:address transaction:transaction];
    }];
    return [self initWithAddress:address nameComponents:nameComponents colorName:colorName diameter:diameter];
}

- (instancetype)initWithAddress:(SignalServiceAddress *)address
                      colorName:(ConversationColorName)colorName
                       diameter:(NSUInteger)diameter
                    transaction:(SDSAnyReadTransaction *)transaction
{
    // Components for avatar initials.
    NSPersonNameComponents *_Nullable nameComponents = [self.contactsManager nameComponentsForAddress:address
                                                                                          transaction:transaction];
    return [self initWithAddress:address nameComponents:nameComponents colorName:colorName diameter:diameter];
}

- (instancetype)initWithNonSignalNameComponents:(NSPersonNameComponents *)nonSignalNameComponents
                                      colorSeed:(NSString *)colorSeed
                                       diameter:(NSUInteger)diameter
{
    ConversationColorName colorName = [TSThread stableColorNameForNewConversationWithString:colorSeed];
    return [self initWithAddress:nil nameComponents:nonSignalNameComponents colorName:colorName diameter:diameter];
}

- (instancetype)initForLocalUserWithDiameter:(NSUInteger)diameter
{
    OWSAssertDebug(diameter > 0);
    OWSAssertDebug(TSAccountManager.localAddress.isValid);

    __block OWSContactAvatarBuilder *instance;
    [self.databaseStorage uiReadWithBlock:^(SDSAnyReadTransaction *transaction) {
        instance = [self initWithAddress:TSAccountManager.localAddress
                               colorName:ConversationColorNameDefault
                                diameter:diameter
                             transaction:transaction];
    }];
    return instance;
}

- (instancetype)initForLocalUserWithDiameter:(NSUInteger)diameter transaction:(SDSAnyReadTransaction *)transaction
{
    OWSAssertDebug(diameter > 0);
    OWSAssertDebug(TSAccountManager.localAddress.isValid);

    return [self initWithAddress:TSAccountManager.localAddress
                       colorName:ConversationColorNameDefault
                        diameter:diameter
                     transaction:transaction];
}

+ (nullable UIImage *)buildImageForAddress:(SignalServiceAddress *)address
                                  diameter:(NSUInteger)diameter
                               transaction:(SDSAnyReadTransaction *)transaction
{
    ConversationColorName color = [self.contactsManager conversationColorNameForAddress:address
                                                                            transaction:transaction];
    return [[[self alloc] initWithAddress:address
                                colorName:color
                                 diameter:diameter
                              transaction:transaction] build];
}

#pragma mark - Dependencies

+ (OWSContactsManager *)contactsManager
{
    return (OWSContactsManager *)SSKEnvironment.shared.contactsManager;
}

#pragma mark - Instance methods

- (nullable UIImage *)buildSavedImage
{
    if (!self.address.isValid) {
        return nil;
    }

    if (self.address.isLocalAddress) {
        return self.buildImageForLocalUser;
    }

    return [OWSContactAvatarBuilder.contactsManager imageForAddressWithSneakyTransaction:self.address];
}

- (nullable UIImage *)buildSavedImageWithTransaction:(SDSAnyReadTransaction *)transaction
{
    if (!self.address.isValid) {
        return nil;
    }

    if (self.address.isLocalAddress) {
        return self.buildImageForLocalUser;
    }

    return [OWSContactAvatarBuilder.contactsManager imageForAddress:self.address transaction:transaction];
}

- (nullable UIImage *)buildImageForLocalUser
{
    OWSCAssertDebug(self.address.isLocalAddress);
    NSString *noteToSelfCacheKey = [NSString stringWithFormat:@"%@:note-to-self", self.cacheKey];
    UIImage *_Nullable cachedAvatar =
        [OWSContactAvatarBuilder.contactsManager getImageFromAvatarCacheWithKey:noteToSelfCacheKey
                                                                       diameter:(CGFloat)self.diameter];
    if (cachedAvatar) {
        return cachedAvatar;
    }

    UIImage *image = [self noteToSelfImageWithConversationColorName:self.colorName diameter:(CGFloat)self.diameter];
    if (!image) {
        OWSFailDebug(@"Could not generate avatar.");
        return nil;
    }

    [OWSContactAvatarBuilder.contactsManager setImageForAvatarCache:image
                                                             forKey:noteToSelfCacheKey
                                                           diameter:self.diameter];
    return image;
}

- (id)cacheKey
{
    if (self.address.isValid) {
        return [NSString stringWithFormat:@"%@-%d", self.address.stringForDisplay, Theme.isDarkThemeEnabled];
    } else {
        return [NSString stringWithFormat:@"%@-%d", self.contactInitials, Theme.isDarkThemeEnabled];
    }
}

- (nullable NSString *)contactInitials
{
    if (self.contactNameComponents == nil) {
        return nil;
    }

    NSString *_Nullable abbreviation = [NSPersonNameComponentsFormatter
        localizedStringFromPersonNameComponents:self.contactNameComponents
                                          style:NSPersonNameComponentsFormatterStyleAbbreviated
                                        options:0];
    if (abbreviation.length > 0 && abbreviation.length < 4) {
        return abbreviation;
    }

    // Some languages, such as Arabic, don't natively support abbreviations or
    // have default abbreviations that are too long. In this case, we will not
    // show an abbreviation. This matches the behavior of iMessage.
    return nil;
}

- (nullable UIImage *)buildDefaultImage
{
    UIImage *_Nullable cachedAvatar =
        [OWSContactAvatarBuilder.contactsManager getImageFromAvatarCacheWithKey:self.cacheKey
                                                                       diameter:(CGFloat)self.diameter];
    if (cachedAvatar) {
        return cachedAvatar;
    }

    UIColor *color = [OWSConversationColor conversationColorOrDefaultForColorName:self.colorName].themeColor;
    OWSAssertDebug(color);

    UIImage *_Nullable image;
    if (self.contactInitials.length == 0) {
        // We don't have a name for this contact, so we can't make an "initials" image.

        UIImage *icon;
        if (self.diameter > kStandardAvatarSize) {
            icon = [UIImage imageNamed:@"contact-avatar-1024"];
        } else {
            icon = [UIImage imageNamed:@"contact-avatar-84"];
        }
        CGFloat assetWidthPixels = CGImageGetWidth(icon.CGImage);
        // The contact-avatar asset is designed to be 28pt if the avatar is kStandardAvatarSize.
        // Adjust its size to reflect the actual output diameter.
        // We use an oversize 1024px version of the asset to ensure quality results for larger avatars.
        CGFloat scaling = (self.diameter / (CGFloat)kStandardAvatarSize) * (28 / assetWidthPixels);

        CGSize iconSize = CGSizeScale(icon.size, scaling);
        image = [OWSAvatarBuilder avatarImageWithIcon:icon
                                             iconSize:iconSize
                                      backgroundColor:color
                                             diameter:self.diameter];
    } else {
        image = [OWSAvatarBuilder avatarImageWithInitials:self.contactInitials
                                          backgroundColor:color
                                                 diameter:self.diameter];
    }

    if (!image) {
        OWSFailDebug(@"Could not generate avatar.");
        return nil;
    }

    [OWSContactAvatarBuilder.contactsManager setImageForAvatarCache:image forKey:self.cacheKey diameter:self.diameter];
    return image;
}

- (nullable UIImage *)noteToSelfImageWithConversationColorName:(ConversationColorName)conversationColorName
                                                      diameter:(CGFloat)diameter
{
    UIImage *iconImage = [[UIImage imageNamed:@"note-112"] asTintedImageWithColor:UIColor.whiteColor];
    UIColor *backgroundColor = [OWSConversationColor conversationColorOrDefaultForColorName:conversationColorName].themeColor;

    CGFloat circleWidth = diameter;
    UIGraphicsBeginImageContextWithOptions(CGSizeMake(circleWidth, circleWidth), NO, 0.0);
    CGContextRef _Nullable context = UIGraphicsGetCurrentContext();
    if (context == nil) {
        OWSFailDebug(@"failure: context was unexpectedly nil");
        return nil;
    }
    [backgroundColor setFill];
    CGContextFillRect(context, CGRectMake(0, 0, circleWidth, circleWidth));

    CGFloat iconWidth = diameter * (CGFloat)0.625;
    CGFloat iconOffset = (circleWidth - iconWidth) / 2;
    CGRect iconRect = CGRectMake(iconOffset, iconOffset, iconWidth, iconWidth);
    [iconImage drawInRect:iconRect];

    UIImage *paddedImage = UIGraphicsGetImageFromCurrentImageContext();
    if (paddedImage == nil) {
        OWSFailDebug(@"failure: paddedImage was unexpectedly nil");
        return nil;
    }
    UIGraphicsEndImageContext();

    return paddedImage;
}

@end

NS_ASSUME_NONNULL_END