Implement a nice money input field.

Telegram/Resources/langs/lang.strings

@@ -1891,9 +1891,10 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 "lng_payments_password_title" = "Payment Confirmation";
 "lng_payments_password_description" = "Your card {card} is on file. To pay with this card, please enter your 2-Step-Verification password.";
 "lng_payments_password_submit" = "Pay";
-"lng_payments_tips_label" = "Tips";
-"lng_payments_tips_title" = "Tips";
-"lng_payments_tips_enter" = "Enter tips amount";
+"lng_payments_tips_label" = "Tip (Optional)";
+"lng_payments_tips_add" = "Add Tip";
+"lng_payments_tips_box_title" = "Add Tip";
+"lng_payments_tips_max" = "Max possible tip amount: {amount}";
 
 "lng_call_status_incoming" = "is calling you...";
 "lng_call_status_connecting" = "connecting...";

Telegram/SourceFiles/payments/payments_checkout_process.cpp

@@ -418,7 +418,8 @@ bool CheckoutProcess::panelWebviewNavigationAttempt(const QString &uri) {
 }
 
 void CheckoutProcess::panelCancelEdit() {
-	if (_submitState != SubmitState::None) {
+	if (_submitState != SubmitState::None
+		&& _submitState != SubmitState::Validated) {
 		return;
 	}
 	showForm();
@@ -463,7 +464,8 @@ void CheckoutProcess::showForm() {
 }
 
 void CheckoutProcess::showEditInformation(Ui::InformationField field) {
-	if (_submitState != SubmitState::None) {
+	if (_submitState != SubmitState::None
+		&& _submitState != SubmitState::Validated) {
 		return;
 	}
 	_panel->showEditInformation(
@@ -473,6 +475,8 @@ void CheckoutProcess::showEditInformation(Ui::InformationField field) {
 }
 
 void CheckoutProcess::showInformationError(Ui::InformationField field) {
+	Expects(_submitState != SubmitState::Validated);
+
 	if (_submitState != SubmitState::None) {
 		return;
 	}
@@ -483,7 +487,8 @@ void CheckoutProcess::showInformationError(Ui::InformationField field) {
 }
 
 void CheckoutProcess::showCardError(Ui::CardField field) {
-	if (_submitState != SubmitState::None) {
+	if (_submitState != SubmitState::None
+		&& _submitState != SubmitState::Validated) {
 		return;
 	}
 	_panel->showCardError(_form->paymentMethod().ui.native, field);

Telegram/SourceFiles/payments/ui/payments.style

@@ -59,6 +59,10 @@ paymentsIconPhone: icon {{ "payments/payment_phone", menuIconFg }};
 paymentsIconShippingMethod: icon {{ "payments/payment_shipping", menuIconFg }};
 
 paymentsField: defaultInputField;
+paymentsFieldAdditional: FlatLabel(defaultFlatLabel) {
+	style: boxTextStyle;
+}
+
 paymentsFieldPadding: margins(28px, 0px, 28px, 2px);
 paymentsSaveCheckboxPadding: margins(28px, 20px, 28px, 8px);
 paymentsExpireCvcSkip: 34px;
@@ -79,3 +83,9 @@ paymentsShippingPrice: FlatLabel(defaultFlatLabel) {
 }
 paymentsShippingLabelPosition: point(43px, 8px);
 paymentsShippingPricePosition: point(43px, 29px);
+
+paymentTipsErrorLabel: FlatLabel(defaultFlatLabel) {
+	minWidth: 275px;
+	textFg: boxTextFgError;
+}
+paymentTipsErrorPadding: margins(22px, 6px, 22px, 0px);

Telegram/SourceFiles/payments/ui/payments_field.cpp

@@ -9,6 +9,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 
 #include "ui/widgets/input_fields.h"
 #include "ui/boxes/country_select_box.h"
+#include "ui/text/format_values.h"
 #include "ui/ui_utility.h"
 #include "ui/special_fields.h"
 #include "data/data_countries.h"
@@ -16,12 +17,190 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "base/event_filter.h"
 #include "styles/style_payments.h"
 
+#include <QtCore/QRegularExpression>
+
 namespace Payments::Ui {
 namespace {
 
+struct SimpleFieldState {
+	QString value;
+	int position = 0;
+};
+
+[[nodiscard]] char FieldThousandsSeparator(const CurrencyRule &rule) {
+	return (rule.thousands == '.' || rule.thousands == ',')
+		? ' '
+		: rule.thousands;
+}
+
+[[nodiscard]] QString RemoveNonNumbers(QString value) {
+	return value.replace(QRegularExpression("[^0-9]"), QString());
+}
+
+[[nodiscard]] SimpleFieldState CleanMoneyState(
+		const CurrencyRule &rule,
+		SimpleFieldState state) {
+	const auto withDecimal = state.value.replace(
+		QChar('.'),
+		rule.decimal
+	).replace(
+		QChar(','),
+		rule.decimal
+	);
+	const auto digitsLimit = 16 - rule.exponent;
+	const auto beforePosition = state.value.mid(0, state.position);
+	auto decimalPosition = withDecimal.lastIndexOf(rule.decimal);
+	if (decimalPosition < 0) {
+		state = {
+			.value = RemoveNonNumbers(state.value),
+			.position = RemoveNonNumbers(beforePosition).size(),
+		};
+	} else {
+		const auto onlyNumbersBeforeDecimal = RemoveNonNumbers(
+			state.value.mid(0, decimalPosition));
+		state = {
+			.value = (onlyNumbersBeforeDecimal
+				+ QChar(rule.decimal)
+				+ RemoveNonNumbers(state.value.mid(decimalPosition + 1))),
+			.position = (RemoveNonNumbers(beforePosition).size()
+				+ (state.position > decimalPosition ? 1 : 0)),
+		};
+		decimalPosition = onlyNumbersBeforeDecimal.size();
+		const auto maxLength = decimalPosition + 1 + rule.exponent;
+		if (state.value.size() > maxLength) {
+			state = {
+				.value = state.value.mid(0, maxLength),
+				.position = std::min(state.position, maxLength),
+			};
+		}
+	}
+	if (!state.value.isEmpty() && state.value[0] == QChar(rule.decimal)) {
+		state = {
+			.value = QChar('0') + state.value,
+			.position = state.position + 1,
+		};
+		if (decimalPosition >= 0) {
+			++decimalPosition;
+		}
+	}
+	auto skip = 0;
+	while (state.value.size() > skip + 1
+		&& state.value[skip] == QChar('0')
+		&& state.value[skip + 1] != QChar(rule.decimal)) {
+		++skip;
+	}
+	state = {
+		.value = state.value.mid(skip),
+		.position = std::max(state.position - skip, 0),
+	};
+	if (decimalPosition >= 0) {
+		Assert(decimalPosition >= skip);
+		decimalPosition -= skip;
+	}
+	if (decimalPosition > digitsLimit) {
+		state = {
+			.value = (state.value.mid(0, digitsLimit)
+				+ state.value.mid(decimalPosition)),
+			.position = (state.position > digitsLimit
+				? std::max(
+					state.position - (decimalPosition - digitsLimit),
+					digitsLimit)
+				: state.position),
+		};
+	}
+	return state;
+}
+
+[[nodiscard]] SimpleFieldState PostprocessMoneyResult(
+		const CurrencyRule &rule,
+		SimpleFieldState result) {
+	const auto position = result.value.indexOf(rule.decimal);
+	const auto from = (position >= 0) ? position : result.value.size();
+	for (auto insertAt = from - 3; insertAt > 0; insertAt -= 3) {
+		result.value.insert(insertAt, QChar(FieldThousandsSeparator(rule)));
+		if (result.position >= insertAt) {
+			++result.position;
+		}
+	}
+	return result;
+}
+
+[[nodiscard]] bool IsBackspace(const FieldValidateRequest &request) {
+	return (request.wasAnchor == request.wasPosition)
+		&& (request.wasPosition == request.nowPosition + 1)
+		&& (request.wasValue.midRef(0, request.wasPosition - 1)
+			== request.nowValue.midRef(0, request.nowPosition))
+		&& (request.wasValue.midRef(request.wasPosition)
+			== request.nowValue.midRef(request.nowPosition));
+}
+
+[[nodiscard]] bool IsDelete(const FieldValidateRequest &request) {
+	return (request.wasAnchor == request.wasPosition)
+		&& (request.wasPosition == request.nowPosition)
+		&& (request.wasValue.midRef(0, request.wasPosition)
+			== request.nowValue.midRef(0, request.nowPosition))
+		&& (request.wasValue.midRef(request.wasPosition + 1)
+			== request.nowValue.midRef(request.nowPosition));
+}
+
+[[nodiscard]] auto MoneyValidator(const CurrencyRule &rule) {
+	return [=](FieldValidateRequest request) {
+		const auto realNowState = [&] {
+			const auto backspaced = IsBackspace(request);
+			const auto deleted = IsDelete(request);
+			if (!backspaced && !deleted) {
+				return CleanMoneyState(rule, {
+					.value = request.nowValue,
+					.position = request.nowPosition,
+				});
+			}
+			const auto realWasState = CleanMoneyState(rule, {
+				.value = request.wasValue,
+				.position = request.wasPosition,
+			});
+			const auto changedValue = deleted
+				? (realWasState.value.mid(0, realWasState.position)
+					+ realWasState.value.mid(realWasState.position + 1))
+				: (realWasState.position > 1)
+				? (realWasState.value.mid(0, realWasState.position - 1)
+					+ realWasState.value.mid(realWasState.position))
+				: realWasState.value.mid(realWasState.position);
+			return SimpleFieldState{
+				.value = changedValue,
+				.position = (deleted
+					? realWasState.position
+					: std::max(realWasState.position - 1, 0))
+			};
+		}();
+		const auto postprocessed = PostprocessMoneyResult(
+			rule,
+			realNowState);
+		return FieldValidateResult{
+			.value = postprocessed.value,
+			.position = postprocessed.position,
+		};
+	};
+}
+
 [[nodiscard]] QString Parse(const FieldConfig &config) {
 	if (config.type == FieldType::Country) {
 		return Data::CountryNameByISO2(config.value);
+	} else if (config.type == FieldType::Money) {
+		const auto amount = config.value.toLongLong();
+		if (!amount) {
+			return QString();
+		}
+		const auto rule = LookupCurrencyRule(config.currency);
+		const auto value = std::abs(amount) / std::pow(10., rule.exponent);
+		const auto precision = (!rule.stripDotZero
+			|| std::floor(value) != value)
+			? rule.exponent
+			: 0;
+		return FormatWithSeparators(
+			value,
+			precision,
+			rule.decimal,
+			FieldThousandsSeparator(rule));
 	}
 	return config.value;
 }
@@ -32,6 +211,20 @@ namespace {
 		const QString &countryIso2) {
 	if (config.type == FieldType::Country) {
 		return countryIso2;
+	} else if (config.type == FieldType::Money) {
+		const auto rule = LookupCurrencyRule(config.currency);
+		const auto real = QString(parsed).replace(
+			QChar(rule.decimal),
+			QChar('.')
+		).replace(
+			QChar(','),
+			QChar('.')
+		).replace(
+			QRegularExpression("[^0-9\\.]"),
+			QString()
+		).toDouble();
+		return QString::number(
+			int64(std::round(real * std::pow(10., rule.exponent))));
 	}
 	return parsed;
 }
@@ -46,7 +239,7 @@ namespace {
 	case FieldType::CardCVC:
 	case FieldType::Country:
 	case FieldType::Phone:
-	case FieldType::PriceAmount:
+	case FieldType::Money:
 		return true;
 	}
 	Unexpected("FieldType in Payments::Ui::UseMaskedField.");
@@ -68,7 +261,7 @@ namespace {
 	case FieldType::CardCVC:
 	case FieldType::Country:
 	case FieldType::Phone:
-	case FieldType::PriceAmount:
+	case FieldType::Money:
 		return base::make_unique_q<RpWidget>(parent);
 	}
 	Unexpected("FieldType in Payments::Ui::CreateWrap.");
@@ -82,9 +275,106 @@ namespace {
 		: static_cast<InputField*>(wrap.get());
 }
 
+[[nodiscard]] MaskedInputField *CreateMoneyField(
+		not_null<RpWidget*> wrap,
+		FieldConfig &config,
+		rpl::producer<> textPossiblyChanged) {
+	struct State {
+		CurrencyRule rule;
+		style::InputField st;
+		QString currencyText;
+		int currencySkip = 0;
+		FlatLabel *left = nullptr;
+		FlatLabel *right = nullptr;
+	};
+	const auto state = wrap->lifetime().make_state<State>(State{
+		.rule = LookupCurrencyRule(config.currency),
+		.st = st::paymentsField,
+	});
+	const auto &rule = state->rule;
+	state->currencySkip = rule.space ? state->st.font->spacew : 0;
+	state->currencyText = ((!rule.left && rule.space)
+		? QString(QChar(' '))
+		: QString()) + (*rule.international
+			? QString(rule.international)
+			: config.currency) + ((rule.left && rule.space)
+				? QString(QChar(' '))
+				: QString());
+	if (rule.left) {
+		state->left = CreateChild<FlatLabel>(
+			wrap.get(),
+			state->currencyText,
+			st::paymentsFieldAdditional);
+	}
+	state->right = CreateChild<FlatLabel>(
+		wrap.get(),
+		QString(),
+		st::paymentsFieldAdditional);
+	const auto leftSkip = state->left
+		? (state->left->naturalWidth() + state->currencySkip)
+		: 0;
+	const auto rightSkip = st::paymentsFieldAdditional.style.font->width(
+		QString(QChar(rule.decimal))
+		+ QString(QChar('0')).repeated(rule.exponent)
+		+ (rule.left ? QString() : state->currencyText));
+	state->st.textMargins += QMargins(leftSkip, 0, rightSkip, 0);
+	state->st.placeholderMargins -= QMargins(leftSkip, 0, rightSkip, 0);
+	const auto result = CreateChild<MaskedInputField>(
+		wrap.get(),
+		state->st,
+		std::move(config.placeholder),
+		Parse(config));
+	result->setPlaceholderHidden(true);
+	if (state->left) {
+		state->left->move(0, state->st.textMargins.top());
+	}
+	const auto updateRight = [=] {
+		const auto text = result->getLastText();
+		const auto width = state->st.font->width(text);
+		const auto rect = result->getTextRect();
+		const auto &rule = state->rule;
+		const auto symbol = QChar(rule.decimal);
+		const auto decimal = text.indexOf(symbol);
+		const auto zeros = (decimal >= 0)
+			? std::max(rule.exponent - (text.size() - decimal - 1), 0)
+			: rule.stripDotZero
+			? 0
+			: rule.exponent;
+		const auto valueDecimalSeparator = (decimal >= 0 || !zeros)
+			? QString()
+			: QString(symbol);
+		const auto zeroString = QString(QChar('0'));
+		const auto valueRightPart = (text.isEmpty() ? zeroString : QString())
+			+ valueDecimalSeparator
+			+ zeroString.repeated(zeros);
+		const auto right = valueRightPart
+			+ (rule.left ? QString() : state->currencyText);
+		state->right->setText(right);
+		state->right->setTextColorOverride(valueRightPart.isEmpty()
+			? std::nullopt
+			: std::make_optional(st::windowSubTextFg->c));
+		state->right->move(
+			(state->st.textMargins.left()
+				+ width
+				+ ((rule.left || !valueRightPart.isEmpty())
+					? 0
+					: state->currencySkip)),
+			state->st.textMargins.top());
+	};
+	std::move(
+		textPossiblyChanged
+	) | rpl::start_with_next(updateRight, result->lifetime());
+	if (state->left) {
+		state->left->raise();
+	}
+	state->right->raise();
+	return result;
+}
+
 [[nodiscard]] MaskedInputField *LookupMaskedField(
 		not_null<RpWidget*> wrap,
-		FieldConfig &config) {
+		FieldConfig &config,
+		rpl::producer<> textPossiblyChanged) {
 	if (!UseMaskedField(config.type)) {
 		return nullptr;
 	}
@@ -96,7 +386,6 @@ namespace {
 	case FieldType::CardExpireDate:
 	case FieldType::CardCVC:
 	case FieldType::Country:
-	case FieldType::PriceAmount:
 		return CreateChild<MaskedInputField>(
 			wrap.get(),
 			st::paymentsField,
@@ -109,6 +398,11 @@ namespace {
 			std::move(config.placeholder),
 			ExtractPhonePrefix(config.defaultPhone),
 			Parse(config));
+	case FieldType::Money:
+		return CreateMoneyField(
+			wrap,
+			config,
+			std::move(textPossiblyChanged));
 	}
 	Unexpected("FieldType in Payments::Ui::LookupMaskedField.");
 }
@@ -119,7 +413,10 @@ Field::Field(QWidget *parent, FieldConfig &&config)
 : _config(config)
 , _wrap(CreateWrap(parent, config))
 , _input(LookupInputField(_wrap.get(), config))
-, _masked(LookupMaskedField(_wrap.get(), config))
+, _masked(LookupMaskedField(
+	_wrap.get(),
+	config,
+	_textPossiblyChanged.events_starting_with({})))
 , _countryIso2(config.value) {
 	if (_masked) {
 		setupMaskedGeometry();
@@ -129,6 +426,8 @@ Field::Field(QWidget *parent, FieldConfig &&config)
 	}
 	if (const auto &validator = config.validator) {
 		setupValidator(validator);
+	} else if (config.type == FieldType::Money) {
+		setupValidator(MoneyValidator(LookupCurrencyRule(config.currency)));
 	}
 	setupFrontBackspace();
 }
@@ -210,7 +509,7 @@ void Field::setupValidator(Fn<ValidateResult(ValidateRequest)> validator) {
 			const auto selectionStart = _masked->selectionStart();
 			const auto selectionEnd = _masked->selectionEnd();
 			return {
-				.value = value(),
+				.value = _masked->getLastText(),
 				.position = position,
 				.anchor = (selectionStart == selectionEnd
 					? position
@@ -221,7 +520,7 @@ void Field::setupValidator(Fn<ValidateResult(ValidateRequest)> validator) {
 		}
 		const auto cursor = _input->textCursor();
 		return {
-			.value = value(),
+			.value = _input->getLastText(),
 			.position = cursor.position(),
 			.anchor = cursor.anchor(),
 		};
@@ -253,6 +552,7 @@ void Field::setupValidator(Fn<ValidateResult(ValidateRequest)> validator) {
 		const auto guard = gsl::finally([&] {
 			_validating = false;
 			save();
+			_textPossiblyChanged.fire({});
 		});
 
 		const auto now = state();

Telegram/SourceFiles/payments/ui/payments_field.h

@@ -29,7 +29,7 @@ enum class FieldType {
 	Country,
 	Phone,
 	Email,
-	PriceAmount,
+	Money,
 };
 
 struct FieldValidateRequest {
@@ -83,6 +83,7 @@ struct FieldConfig {
 	QString value;
 	Fn<FieldValidateResult(FieldValidateRequest)> validator;
 	Fn<void(object_ptr<BoxContent>)> showBox;
+	QString currency;
 	QString defaultPhone;
 	QString defaultCountry;
 };
@@ -124,6 +125,7 @@ private:
 	const base::unique_qptr<RpWidget> _wrap;
 	rpl::event_stream<> _frontBackspace;
 	rpl::event_stream<> _finished;
+	rpl::event_stream<> _textPossiblyChanged; // Must be above _masked.
 	InputField *_input = nullptr;
 	MaskedInputField *_masked = nullptr;
 	QString _countryIso2;

Telegram/SourceFiles/payments/ui/payments_form_summary.cpp

@@ -279,7 +279,9 @@ void FormSummary::setupPrices(not_null<VerticalLayout*> layout) {
 			add(tr::lng_payments_tips_label(tr::now), tips);
 		}
 	} else if (_invoice.tipsMax > 0) {
-		const auto text = formatAmount(_invoice.tipsSelected);
+		const auto text = _invoice.tipsSelected
+			? formatAmount(_invoice.tipsSelected)
+			: tr::lng_payments_tips_add(tr::now);
 		const auto label = addRow(
 			tr::lng_payments_tips_label(tr::now),
 			Ui::Text::Link(text, "internal:edit_tips"));

Telegram/SourceFiles/payments/ui/payments_panel.cpp

@@ -14,6 +14,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "payments/ui/payments_field.h"
 #include "ui/widgets/separate_panel.h"
 #include "ui/widgets/checkbox.h"
+#include "ui/wrap/fade_wrap.h"
 #include "ui/boxes/single_choice_box.h"
 #include "ui/text/format_values.h"
 #include "lang/lang_keys.h"
@@ -23,18 +24,6 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "styles/style_layers.h"
 
 namespace Payments::Ui {
-namespace {
-
-[[nodiscard]] auto PriceAmountValidator(int64 min, int64 max) {
-	return [=](FieldValidateRequest request) {
-		return FieldValidateResult{
-			.value = request.nowValue,
-			.position = request.nowPosition,
-		};
-	};
-}
-
-} // namespace
 
 Panel::Panel(not_null<PanelDelegate*> delegate)
 : _delegate(delegate)
@@ -193,27 +182,52 @@ void Panel::chooseTips(const Invoice &invoice) {
 	const auto min = invoice.tipsMin;
 	const auto max = invoice.tipsMax;
 	const auto now = invoice.tipsSelected;
+	const auto currency = invoice.currency;
 	showBox(Box([=](not_null<Ui::GenericBox*> box) {
-		box->setTitle(tr::lng_payments_tips_title());
-
+		box->setTitle(tr::lng_payments_tips_box_title());
 		const auto row = box->lifetime().make_state<Field>(
 			box,
 			FieldConfig{
-				.type = FieldType::PriceAmount,
-				.placeholder = tr::lng_payments_tips_enter(),
+				.type = FieldType::Money,
 				.value = QString::number(now),
-				.validator = PriceAmountValidator(min, max),
+				.currency = ([&]() -> QString {
+					static auto counter = 0;
+					switch (++counter % 9) {
+					case 0: return "USD";
+					case 1: return "EUR";
+					case 2: return "IRR";
+					case 3: return "BRL";
+					case 4: return "ALL";
+					case 5: return "AZN";
+					case 6: return "CHF";
+					case 7: return "DKK";
+					case 8: return "KZT";
+					}
+					return currency;
+				})(), // #TODO payments currency,
 			});
 		box->setFocusCallback([=] {
 			row->setFocusFast();
 		});
 		box->addRow(row->ownedWidget());
-		box->addRow(object_ptr<FlatLabel>(box, "Min: " + QString::number(min), st::defaultFlatLabel));
-		box->addRow(object_ptr<FlatLabel>(box, "Max: " + QString::number(max), st::defaultFlatLabel));
+		const auto errorWrap = box->addRow(
+			object_ptr<FadeWrap<FlatLabel>>(
+				box,
+				object_ptr<FlatLabel>(
+					box,
+					tr::lng_payments_tips_max(
+						lt_amount,
+						rpl::single(FillAmountAndCurrency(max, currency))),
+					st::paymentTipsErrorLabel)),
+			st::paymentTipsErrorPadding);
+		errorWrap->hide(anim::type::instant);
 		box->addButton(tr::lng_settings_save(), [=] {
 			const auto value = row->value().toLongLong();
-			if (value < min || value > max) {
+			if (value < min) {
 				row->showError();
+			} else if (value > max) {
+				row->showError();
+				errorWrap->show(anim::type::normal);
 			} else {
 				_delegate->panelChangeTips(value);
 				box->closeBox();

Telegram/SourceFiles/ui/text/format_values.cpp

@@ -45,40 +45,6 @@ namespace {
 	return phrase(tr::now, lt_ready, readyStr, lt_total, totalStr, lt_mb, mb);
 }
 
-[[nodiscard]] QString FormatWithSeparators(
-		double amount,
-		int precision,
-		char decimal,
-		char thousands) {
-	Expects(decimal != 0);
-
-	// Thanks https://stackoverflow.com/a/5058949
-	struct FormattingHelper : std::numpunct<char> {
-		FormattingHelper(char decimal, char thousands)
-		: decimal(decimal)
-		, thousands(thousands) {
-		}
-
-		char do_decimal_point() const override { return decimal; }
-		char do_thousands_sep() const override { return thousands; }
-
-		char decimal = '.';
-		char thousands = ',';
-	};
-
-	auto stream = std::ostringstream();
-	stream.imbue(std::locale(
-		stream.getloc(),
-		new FormattingHelper(decimal, thousands ? thousands : '?')));
-	stream.precision(precision);
-	stream << std::fixed << amount;
-	auto result = QString::fromStdString(stream.str());
-	if (!thousands) {
-		result.replace('?', QString());
-	}
-	return result;
-}
-
 } // namespace
 
 QString FormatSizeText(qint64 size) {
@@ -162,16 +128,37 @@ QString FormatPlayedText(qint64 played, qint64 duration) {
 }
 
 QString FillAmountAndCurrency(int64 amount, const QString &currency) {
-	struct Rule {
-		//const char *name = "";
-		//const char *native = "";
-		const char *international = "";
-		char thousands = ',';
-		char decimal = '.';
-		bool left = true;
-		bool space = false;
-	};
-	static const auto kRules = std::vector<std::pair<QString, Rule>>{
+	const auto rule = LookupCurrencyRule(currency);
+
+	const auto prefix = (amount < 0)
+		? QString::fromUtf8("\xe2\x88\x92")
+		: QString();
+	const auto value = std::abs(amount) / std::pow(10., rule.exponent);
+	const auto name = (*rule.international)
+		? QString::fromUtf8(rule.international)
+		: currency;
+	auto result = prefix;
+	if (rule.left) {
+		result.append(name);
+		if (rule.space) result.append(' ');
+	}
+	const auto precision = (!rule.stripDotZero || std::floor(value) != value)
+		? rule.exponent
+		: 0;
+	result.append(FormatWithSeparators(
+		value,
+		precision,
+		rule.decimal,
+		rule.thousands));
+	if (!rule.left) {
+		if (rule.space) result.append(' ');
+		result.append(name);
+	}
+	return result;
+}
+
+CurrencyRule LookupCurrencyRule(const QString &currency) {
+	static const auto kRules = std::vector<std::pair<QString, CurrencyRule>>{
 		{ u"AED"_q, { "", ',', '.', true, true } },
 		{ u"AFN"_q, {} },
 		{ u"ALL"_q, { "", '.', ',', false } },
@@ -185,11 +172,11 @@ QString FillAmountAndCurrency(int64 amount, const QString &currency) {
 		{ u"BND"_q, { "", '.', ',', } },
 		{ u"BOB"_q, { "", '.', ',', true, true } },
 		{ u"BRL"_q, { "R$", '.', ',', true, true } },
-		{ u"BHD"_q, { "", ',', '.', true, true } },
-		{ u"BYR"_q, { "", ' ', ',', false, true } },
+		{ u"BHD"_q, { "", ',', '.', true, true, 3 } },
+		{ u"BYR"_q, { "", ' ', ',', false, true, 0 } },
 		{ u"CAD"_q, { "CA$" } },
 		{ u"CHF"_q, { "", '\'', '.', false, true } },
-		{ u"CLP"_q, { "", '.', ',', true, true } },
+		{ u"CLP"_q, { "", '.', ',', true, true, 0 } },
 		{ u"CNY"_q, { "\x43\x4E\xC2\xA5" } },
 		{ u"COP"_q, { "", '.', ',', true, true } },
 		{ u"CRC"_q, { "", '.', ',', } },
@@ -209,12 +196,12 @@ QString FillAmountAndCurrency(int64 amount, const QString &currency) {
 		{ u"IDR"_q, { "", '.', ',', } },
 		{ u"ILS"_q, { "\xE2\x82\xAA", ',', '.', true, true } },
 		{ u"INR"_q, { "\xE2\x82\xB9" } },
-		{ u"ISK"_q, { "", '.', ',', false, true } },
+		{ u"ISK"_q, { "", '.', ',', false, true, 0 } },
 		{ u"JMD"_q, {} },
-		{ u"JPY"_q, { "\xC2\xA5" } },
+		{ u"JPY"_q, { "\xC2\xA5", ',', '.', true, false, 0 } },
 		{ u"KES"_q, {} },
 		{ u"KGS"_q, { "", ' ', '-', false, true } },
-		{ u"KRW"_q, { "\xE2\x82\xA9" } },
+		{ u"KRW"_q, { "\xE2\x82\xA9", ',', '.', true, false, 0 } },
 		{ u"KZT"_q, { "", ' ', '-', } },
 		{ u"LBP"_q, { "", ',', '.', true, true } },
 		{ u"LKR"_q, { "", ',', '.', true, true } },
@@ -236,7 +223,7 @@ QString FillAmountAndCurrency(int64 amount, const QString &currency) {
 		{ u"PHP"_q, {} },
 		{ u"PKR"_q, {} },
 		{ u"PLN"_q, { "", ' ', ',', false, true } },
-		{ u"PYG"_q, { "", '.', ',', true, true } },
+		{ u"PYG"_q, { "", '.', ',', true, true, 0 } },
 		{ u"QAR"_q, { "", ',', '.', true, true } },
 		{ u"RON"_q, { "", '.', ',', false, true } },
 		{ u"RSD"_q, { "", '.', ',', false, true } },
@@ -251,27 +238,27 @@ QString FillAmountAndCurrency(int64 amount, const QString &currency) {
 		{ u"TWD"_q, { "NT$" } },
 		{ u"TZS"_q, {} },
 		{ u"UAH"_q, { "", ' ', ',', false } },
-		{ u"UGX"_q, {} },
+		{ u"UGX"_q, { "", ',', '.', true, false, 0 } },
 		{ u"USD"_q, { "$" } },
 		{ u"UYU"_q, { "", '.', ',', true, true } },
 		{ u"UZS"_q, { "", ' ', ',', false, true } },
-		{ u"VND"_q, { "\xE2\x82\xAB", '.', ',', false, true } },
+		{ u"VND"_q, { "\xE2\x82\xAB", '.', ',', false, true, 0 } },
 		{ u"YER"_q, { "", ',', '.', true, true } },
 		{ u"ZAR"_q, { "", ',', '.', true, true } },
-		{ u"IRR"_q, { "", ',', '/', false, true } },
-		{ u"IQD"_q, { "", ',', '.', true, true } },
+		{ u"IRR"_q, { "", ',', '/', false, true, 2, true } },
+		{ u"IQD"_q, { "", ',', '.', true, true, 3 } },
 		{ u"VEF"_q, { "", '.', ',', true, true } },
 		{ u"SYP"_q, { "", ',', '.', true, true } },
 
-		//{ u"VUV"_q, { "", ',', '.', false } },
+		//{ u"VUV"_q, { "", ',', '.', false, false, 0 } },
 		//{ u"WST"_q, {} },
-		//{ u"XAF"_q, { "FCFA", ',', '.', false } },
+		//{ u"XAF"_q, { "FCFA", ',', '.', false, false, 0 } },
 		//{ u"XCD"_q, {} },
-		//{ u"XOF"_q, { "CFA", ' ', ',', false } },
-		//{ u"XPF"_q, { "", ',', '.', false } },
+		//{ u"XOF"_q, { "CFA", ' ', ',', false, false, 0 } },
+		//{ u"XPF"_q, { "", ',', '.', false, false, 0 } },
 		//{ u"ZMW"_q, {} },
 		//{ u"ANG"_q, {} },
-		//{ u"RWF"_q, { "", ' ', ',', true, true } },
+		//{ u"RWF"_q, { "", ' ', ',', true, true, 0 } },
 		//{ u"PGK"_q, {} },
 		//{ u"TOP"_q, {} },
 		//{ u"SBD"_q, {} },
@@ -286,109 +273,85 @@ QString FillAmountAndCurrency(int64 amount, const QString &currency) {
 		//{ u"AOA"_q, {} },
 		//{ u"AWG"_q, {} },
 		//{ u"BBD"_q, {} },
-		//{ u"BIF"_q, { "", ',', '.', false } },
+		//{ u"BIF"_q, { "", ',', '.', false, false, 0 } },
 		//{ u"BMD"_q, {} },
 		//{ u"BSD"_q, {} },
 		//{ u"BWP"_q, {} },
 		//{ u"BZD"_q, {} },
 		//{ u"CDF"_q, { "", ',', '.', false } },
-		//{ u"CVE"_q, {} },
-		//{ u"DJF"_q, { "", ',', '.', false } },
+		//{ u"CVE"_q, { "", ',', '.', true, false, 0 } },
+		//{ u"DJF"_q, { "", ',', '.', false, false, 0 } },
 		//{ u"ETB"_q, {} },
 		//{ u"FJD"_q, {} },
 		//{ u"FKP"_q, {} },
 		//{ u"GIP"_q, {} },
 		//{ u"GMD"_q, { "", ',', '.', false } },
-		//{ u"GNF"_q, { "", ',', '.', false } },
+		//{ u"GNF"_q, { "", ',', '.', false, false, 0 } },
 		//{ u"GYD"_q, {} },
 		//{ u"HTG"_q, {} },
 		//{ u"KHR"_q, { "", ',', '.', false } },
-		//{ u"KMF"_q, { "", ',', '.', false } },
+		//{ u"KMF"_q, { "", ',', '.', false, false, 0 } },
 		//{ u"KYD"_q, {} },
 		//{ u"LAK"_q, { "", ',', '.', false } },
 		//{ u"LRD"_q, {} },
 		//{ u"LSL"_q, { "", ',', '.', false } },
-		//{ u"MGA"_q, {} },
+		//{ u"MGA"_q, { "", ',', '.', true, false, 0 } },
 		//{ u"MKD"_q, { "", '.', ',', false, true } },
 		//{ u"MOP"_q, {} },
 		//{ u"MWK"_q, {} },
 		//{ u"NAD"_q, {} },
+		//{ u"CLF"_q, { "", ',', '.', true, false, 4 } },
+		//{ u"JOD"_q, { "", ',', '.', true, false, 3 } },
+		//{ u"KWD"_q, { "", ',', '.', true, false, 3 } },
+		//{ u"LYD"_q, { "", ',', '.', true, false, 3 } },
+		//{ u"OMR"_q, { "", ',', '.', true, false, 3 } },
+		//{ u"TND"_q, { "", ',', '.', true, false, 3 } },
+		//{ u"UYI"_q, { "", ',', '.', true, false, 0 } },
+		//{ u"MRO"_q, { "", ',', '.', true, false, 1 } },
 	};
 	static const auto kRulesMap = [] {
 		// flat_multi_map_pair_type lacks some required constructors :(
-		auto &&pairs = kRules | ranges::views::transform([](auto &&pair) {
-			return base::flat_multi_map_pair_type<QString, Rule>(
+		auto &&list = kRules | ranges::views::transform([](auto &&pair) {
+			return base::flat_multi_map_pair_type<QString, CurrencyRule>(
 				pair.first,
 				pair.second);
 		});
-		return base::flat_map<QString, Rule>(begin(pairs), end(pairs));
+		return base::flat_map<QString, CurrencyRule>(begin(list), end(list));
 	}();
-	static const auto kExponents = base::flat_map<QString, int>{
-		{ u"CLF"_q, 4 },
-		{ u"BHD"_q, 3 },
-		{ u"IQD"_q, 3 },
-		{ u"JOD"_q, 3 },
-		{ u"KWD"_q, 3 },
-		{ u"LYD"_q, 3 },
-		{ u"OMR"_q, 3 },
-		{ u"TND"_q, 3 },
-		{ u"BIF"_q, 0 },
-		{ u"BYR"_q, 0 },
-		{ u"CLP"_q, 0 },
-		{ u"CVE"_q, 0 },
-		{ u"DJF"_q, 0 },
-		{ u"GNF"_q, 0 },
-		{ u"ISK"_q, 0 },
-		{ u"JPY"_q, 0 },
-		{ u"KMF"_q, 0 },
-		{ u"KRW"_q, 0 },
-		{ u"MGA"_q, 0 },
-		{ u"PYG"_q, 0 },
-		{ u"RWF"_q, 0 },
-		{ u"UGX"_q, 0 },
-		{ u"UYI"_q, 0 },
-		{ u"VND"_q, 0 },
-		{ u"VUV"_q, 0 },
-		{ u"XAF"_q, 0 },
-		{ u"XOF"_q, 0 },
-		{ u"XPF"_q, 0 },
-		{ u"MRO"_q, 1 },
+	const auto i = kRulesMap.find(currency);
+	return (i != end(kRulesMap)) ? i->second : CurrencyRule{};
+}
+
+[[nodiscard]] QString FormatWithSeparators(
+		double amount,
+		int precision,
+		char decimal,
+		char thousands) {
+	Expects(decimal != 0);
+
+	// Thanks https://stackoverflow.com/a/5058949
+	struct FormattingHelper : std::numpunct<char> {
+		FormattingHelper(char decimal, char thousands)
+		: decimal(decimal)
+		, thousands(thousands) {
+		}
+
+		char do_decimal_point() const override { return decimal; }
+		char do_thousands_sep() const override { return thousands; }
+
+		char decimal = '.';
+		char thousands = ',';
 	};
 
-	const auto prefix = (amount < 0)
-		? QString::fromUtf8("\xe2\x88\x92")
-		: QString();
-
-	const auto exponentIt = kExponents.find(currency);
-	const auto exponent = (exponentIt != end(kExponents))
-		? exponentIt->second
-		: 2;
-	const auto value = std::abs(amount) / std::pow(10., exponent);
-	const auto ruleIt = kRulesMap.find(currency);
-	if (ruleIt == end(kRulesMap)) {
-		return prefix + QLocale::system().toCurrencyString(value, currency);
-	}
-	const auto &rule = ruleIt->second;
-	const auto name = (*rule.international)
-		? QString::fromUtf8(rule.international)
-		: currency;
-	auto result = prefix;
-	if (rule.left) {
-		result.append(name);
-		if (rule.space) result.append(' ');
-	}
-	const auto precision = (currency != u"IRR"_q
-		|| std::floor(value) != value)
-		? exponent
-		: 0;
-	result.append(FormatWithSeparators(
-		value,
-		precision,
-		rule.decimal,
-		rule.thousands));
-	if (!rule.left) {
-		if (rule.space) result.append(' ');
-		result.append(name);
+	auto stream = std::ostringstream();
+	stream.imbue(std::locale(
+		stream.getloc(),
+		new FormattingHelper(decimal, thousands ? thousands : '?')));
+	stream.precision(precision);
+	stream << std::fixed << amount;
+	auto result = QString::fromStdString(stream.str());
+	if (!thousands) {
+		result.replace('?', QString());
 	}
 	return result;
 }

Telegram/SourceFiles/ui/text/format_values.h

@@ -23,9 +23,25 @@ inline constexpr auto FileStatusSizeFailed = 0x7FFFFFF2;
 [[nodiscard]] QString FormatGifAndSizeText(qint64 size);
 [[nodiscard]] QString FormatPlayedText(qint64 played, qint64 duration);
 
+struct CurrencyRule {
+	const char *international = "";
+	char thousands = ',';
+	char decimal = '.';
+	bool left = true;
+	bool space = false;
+	int exponent = 2;
+	bool stripDotZero = false;
+};
+
 [[nodiscard]] QString FillAmountAndCurrency(
 	int64 amount,
 	const QString &currency);
+[[nodiscard]] CurrencyRule LookupCurrencyRule(const QString &currency);
+[[nodiscard]] QString FormatWithSeparators(
+	double amount,
+	int precision,
+	char decimal,
+	char thousands);
 
 [[nodiscard]] QString ComposeNameString(
 	const QString &filename,