session-ios/SignalMessaging/ViewControllers/ViewControllerUtils.m
Michael Kirk c7662b5a86 Step 2/2 %s/OWSAssert/OWSAssertDebug for existing previous assert semantics
Going forward, we want to prefer safer asserts, but we don't want to blindly
apply crashing asserts across the codebase
2018-09-07 10:00:48 -06:00

157 lines
7.6 KiB
Objective-C

//
// Copyright (c) 2018 Open Whisper Systems. All rights reserved.
//
#import "ViewControllerUtils.h"
#import "NSString+OWS.h"
#import "PhoneNumber.h"
#import <AVFoundation/AVFoundation.h>
#import <SignalMessaging/Environment.h>
#import <SignalServiceKit/PhoneNumberUtil.h>
NS_ASSUME_NONNULL_BEGIN
NSString *const TappedStatusBarNotification = @"TappedStatusBarNotification";
const NSUInteger kMin2FAPinLength = 4;
const NSUInteger kMax2FAPinLength = 16;
@implementation ViewControllerUtils
+ (void)phoneNumberTextField:(UITextField *)textField
shouldChangeCharactersInRange:(NSRange)range
replacementString:(NSString *)insertionText
countryCode:(NSString *)countryCode
{
// Phone numbers takes many forms.
//
// * We only want to let the user enter decimal digits.
// * The user shouldn't have to enter hyphen, parentheses or whitespace;
// the phone number should be formatted automatically.
// * The user should be able to copy and paste freely.
// * Invalid input should be simply ignored.
//
// We accomplish this by being permissive and trying to "take as much of the user
// input as possible".
//
// * Always accept deletes.
// * Ignore invalid input.
// * Take partial input if possible.
NSString *oldText = textField.text;
// Construct the new contents of the text field by:
// 1. Determining the "left" substring: the contents of the old text _before_ the deletion range.
// Filtering will remove non-decimal digit characters like hyphen "-".
NSString *left = [oldText substringToIndex:range.location].digitsOnly;
// 2. Determining the "right" substring: the contents of the old text _after_ the deletion range.
NSString *right = [oldText substringFromIndex:range.location + range.length].digitsOnly;
// 3. Determining the "center" substring: the contents of the new insertion text.
NSString *center = insertionText.digitsOnly;
// 3a. If user hits backspace, they should always delete a _digit_ to the
// left of the cursor, even if the text _immediately_ to the left of
// cursor is "formatting text" (e.g. whitespace, a hyphen or a
// parentheses).
bool isJustDeletion = insertionText.length == 0;
if (isJustDeletion) {
NSString *deletedText = [oldText substringWithRange:range];
BOOL didDeleteFormatting = (deletedText.length == 1 && deletedText.digitsOnly.length < 1);
if (didDeleteFormatting && left.length > 0) {
left = [left substringToIndex:left.length - 1];
}
}
// 4. Construct the "raw" new text by concatenating left, center and right.
NSString *textAfterChange = [[left stringByAppendingString:center] stringByAppendingString:right];
// 4a. Ensure we don't exceed the maximum length for a e164 phone number,
// 15 digits, per: https://en.wikipedia.org/wiki/E.164
//
// NOTE: The actual limit is 18, not 15, because of certain invalid phone numbers in Germany.
// https://github.com/googlei18n/libphonenumber/blob/master/FALSEHOODS.md
const int kMaxPhoneNumberLength = 18;
if (textAfterChange.length > kMaxPhoneNumberLength) {
textAfterChange = [textAfterChange substringToIndex:kMaxPhoneNumberLength];
}
// 5. Construct the "formatted" new text by inserting a hyphen if necessary.
// reformat the phone number, trying to keep the cursor beside the inserted or deleted digit
NSUInteger cursorPositionAfterChange = MIN(left.length + center.length, textAfterChange.length);
NSString *textAfterReformat =
[PhoneNumber bestEffortFormatPartialUserSpecifiedTextToLookLikeAPhoneNumber:textAfterChange
withSpecifiedCountryCodeString:countryCode];
NSUInteger cursorPositionAfterReformat = [PhoneNumberUtil translateCursorPosition:cursorPositionAfterChange
from:textAfterChange
to:textAfterReformat
stickingRightward:isJustDeletion];
textField.text = textAfterReformat;
UITextPosition *pos =
[textField positionFromPosition:textField.beginningOfDocument offset:(NSInteger)cursorPositionAfterReformat];
[textField setSelectedTextRange:[textField textRangeFromPosition:pos toPosition:pos]];
}
+ (void)ows2FAPINTextField:(UITextField *)textField
shouldChangeCharactersInRange:(NSRange)range
replacementString:(NSString *)insertionText
{
// * We only want to let the user enter decimal digits.
// * The user should be able to copy and paste freely.
// * Invalid input should be simply ignored.
//
// We accomplish this by being permissive and trying to "take as much of the user
// input as possible".
//
// * Always accept deletes.
// * Ignore invalid input.
// * Take partial input if possible.
NSString *oldText = textField.text;
// Construct the new contents of the text field by:
// 1. Determining the "left" substring: the contents of the old text _before_ the deletion range.
// Filtering will remove non-decimal digit characters.
NSString *left = [oldText substringToIndex:range.location].digitsOnly;
// 2. Determining the "right" substring: the contents of the old text _after_ the deletion range.
NSString *right = [oldText substringFromIndex:range.location + range.length].digitsOnly;
// 3. Determining the "center" substring: the contents of the new insertion text.
NSString *center = insertionText.digitsOnly;
// 4. Construct the "raw" new text by concatenating left, center and right.
NSString *textAfterChange = [[left stringByAppendingString:center] stringByAppendingString:right];
// 5. Ensure we don't exceed the maximum length for a PIN.
if (textAfterChange.length > kMax2FAPinLength) {
textAfterChange = [textAfterChange substringToIndex:kMax2FAPinLength];
}
// 6. Construct the final text.
textField.text = textAfterChange;
NSUInteger cursorPositionAfterChange = MIN(left.length + center.length, textAfterChange.length);
UITextPosition *pos =
[textField positionFromPosition:textField.beginningOfDocument offset:(NSInteger)cursorPositionAfterChange];
[textField setSelectedTextRange:[textField textRangeFromPosition:pos toPosition:pos]];
}
+ (NSString *)examplePhoneNumberForCountryCode:(NSString *)countryCode callingCode:(NSString *)callingCode
{
OWSAssertDebug(countryCode.length > 0);
OWSAssertDebug(callingCode.length > 0);
NSString *examplePhoneNumber = [PhoneNumberUtil examplePhoneNumberForCountryCode:countryCode];
OWSAssertDebug(!examplePhoneNumber || [examplePhoneNumber hasPrefix:callingCode]);
if (examplePhoneNumber && [examplePhoneNumber hasPrefix:callingCode]) {
NSString *formattedPhoneNumber =
[PhoneNumber bestEffortFormatPartialUserSpecifiedTextToLookLikeAPhoneNumber:examplePhoneNumber
withSpecifiedCountryCodeString:countryCode];
if (formattedPhoneNumber.length > 0) {
examplePhoneNumber = formattedPhoneNumber;
}
return [NSString
stringWithFormat:
NSLocalizedString(@"PHONE_NUMBER_EXAMPLE_FORMAT",
@"A format for a label showing an example phone number. Embeds {{the example phone number}}."),
[examplePhoneNumber substringFromIndex:callingCode.length]];
} else {
return @"";
}
}
@end
NS_ASSUME_NONNULL_END