stack_wallet/lib/models/exchange/exchange_form_state.dart
2022-10-15 20:47:59 -06:00

422 lines
11 KiB
Dart

import 'package:decimal/decimal.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:stackwallet/models/exchange/response_objects/currency.dart';
import 'package:stackwallet/models/exchange/response_objects/estimate.dart';
import 'package:stackwallet/models/exchange/response_objects/fixed_rate_market.dart';
import 'package:stackwallet/pages/exchange_view/sub_widgets/exchange_rate_sheet.dart';
import 'package:stackwallet/services/exchange/change_now/change_now_exchange.dart';
import 'package:stackwallet/services/exchange/exchange.dart';
import 'package:stackwallet/services/exchange/simpleswap/simpleswap_exchange.dart';
import 'package:stackwallet/utilities/logger.dart';
class ExchangeFormState extends ChangeNotifier {
Exchange? _exchange;
Exchange? get exchange => _exchange;
set exchange(Exchange? value) {
_exchange = value;
_onExchangeTypeChanged();
}
ExchangeRateType _exchangeType = ExchangeRateType.estimated;
ExchangeRateType get exchangeType => _exchangeType;
set exchangeType(ExchangeRateType value) {
_exchangeType = value;
_onExchangeRateTypeChanged();
}
bool reversed = false;
Decimal? fromAmount;
Decimal? toAmount;
Decimal? minAmount;
Decimal? maxAmount;
Decimal? rate;
Estimate? estimate;
FixedRateMarket? _market;
FixedRateMarket? get market => _market;
Currency? _from;
Currency? _to;
@override
String toString() {
return 'ExchangeFormState: {_exchange: $_exchange, _exchangeType: $_exchangeType, reversed: $reversed, fromAmount: $fromAmount, toAmount: $toAmount, minAmount: $minAmount, maxAmount: $maxAmount, rate: $rate, estimate: $estimate, _market: $_market, _from: $_from, _to: $_to, _onError: $_onError}';
}
String? get fromTicker {
switch (exchangeType) {
case ExchangeRateType.estimated:
return _from?.ticker;
case ExchangeRateType.fixed:
switch (exchange?.name) {
case SimpleSwapExchange.exchangeName:
return _from?.ticker;
case ChangeNowExchange.exchangeName:
return market?.from;
default:
return null;
}
}
}
String? get toTicker {
switch (exchangeType) {
case ExchangeRateType.estimated:
return _to?.ticker;
case ExchangeRateType.fixed:
switch (exchange?.name) {
case SimpleSwapExchange.exchangeName:
return _to?.ticker;
case ChangeNowExchange.exchangeName:
return market?.to;
default:
return null;
}
}
}
void Function(String)? _onError;
Currency? get from => _from;
Currency? get to => _to;
void setCurrencies(Currency from, Currency to) {
_from = from;
_to = to;
}
String get warning {
if (reversed) {
if (toTicker != null && toAmount != null) {
if (minAmount != null &&
toAmount! < minAmount! &&
toAmount! > Decimal.zero) {
return "Minimum amount ${minAmount!.toString()} ${toTicker!.toUpperCase()}";
} else if (maxAmount != null && toAmount! > maxAmount!) {
return "Maximum amount ${maxAmount!.toString()} ${toTicker!.toUpperCase()}";
}
}
} else {
if (fromTicker != null && fromAmount != null) {
if (minAmount != null &&
fromAmount! < minAmount! &&
fromAmount! > Decimal.zero) {
return "Minimum amount ${minAmount!.toString()} ${fromTicker!.toUpperCase()}";
} else if (maxAmount != null && fromAmount! > maxAmount!) {
return "Maximum amount ${maxAmount!.toString()} ${fromTicker!.toUpperCase()}";
}
}
}
return "";
}
String get fromAmountString => fromAmount?.toStringAsFixed(8) ?? "";
String get toAmountString => toAmount?.toStringAsFixed(8) ?? "";
bool get canExchange {
if (exchange?.name == ChangeNowExchange.exchangeName &&
exchangeType == ExchangeRateType.fixed) {
return _market != null &&
fromAmount != null &&
toAmount != null &&
warning.isEmpty;
} else {
return fromAmount != null &&
fromAmount != Decimal.zero &&
toAmount != null &&
rate != null &&
warning.isEmpty;
}
}
void clearAmounts(bool shouldNotifyListeners) {
fromAmount = null;
toAmount = null;
minAmount = null;
maxAmount = null;
rate = null;
if (shouldNotifyListeners) {
notifyListeners();
}
}
Future<void> setFromAmountAndCalculateToAmount(
Decimal newFromAmount,
bool shouldNotifyListeners,
) async {
if (newFromAmount == Decimal.zero) {
toAmount = Decimal.zero;
}
fromAmount = newFromAmount;
reversed = false;
await updateRanges(shouldNotifyListeners: false);
await updateEstimate(
shouldNotifyListeners: false,
reversed: reversed,
);
if (shouldNotifyListeners) {
notifyListeners();
}
}
Future<void> setToAmountAndCalculateFromAmount(
Decimal newToAmount,
bool shouldNotifyListeners,
) async {
if (newToAmount == Decimal.zero) {
fromAmount = Decimal.zero;
}
toAmount = newToAmount;
reversed = true;
await updateRanges(shouldNotifyListeners: false);
await updateEstimate(
shouldNotifyListeners: false,
reversed: reversed,
);
if (shouldNotifyListeners) {
notifyListeners();
}
}
Future<void> updateTo(Currency to, bool shouldNotifyListeners) async {
try {
_to = to;
if (_from == null) {
rate = null;
notifyListeners();
return;
}
await updateRanges(shouldNotifyListeners: false);
await updateEstimate(
shouldNotifyListeners: false,
reversed: reversed,
);
debugPrint(
"_updated TO: _from=${_from!.ticker} _to=${_to!.ticker} _fromAmount=$fromAmount _toAmount=$toAmount rate:$rate for: $exchange");
if (shouldNotifyListeners) {
notifyListeners();
}
} catch (e, s) {
Logging.instance.log("$e\n$s", level: LogLevel.Error);
}
}
Future<void> updateFrom(Currency from, bool shouldNotifyListeners) async {
try {
_from = from;
if (_to == null) {
rate = null;
notifyListeners();
return;
}
await updateRanges(shouldNotifyListeners: false);
await updateEstimate(
shouldNotifyListeners: false,
reversed: reversed,
);
debugPrint(
"_updated FROM: _from=${_from!.ticker} _to=${_to!.ticker} _fromAmount=$fromAmount _toAmount=$toAmount rate:$rate for: $exchange");
if (shouldNotifyListeners) {
notifyListeners();
}
} catch (e, s) {
Logging.instance.log("$e\n$s", level: LogLevel.Error);
}
}
Future<void> updateMarket(
FixedRateMarket? market,
bool shouldNotifyListeners,
) async {
_market = market;
if (_market == null) {
fromAmount = null;
toAmount = null;
} else {
if (fromAmount != null) {
if (fromAmount! <= Decimal.zero) {
toAmount = Decimal.zero;
} else {
await updateRanges(shouldNotifyListeners: false);
await updateEstimate(
shouldNotifyListeners: false,
reversed: reversed,
);
}
}
}
if (shouldNotifyListeners) {
notifyListeners();
}
}
void _onExchangeRateTypeChanged() {
print("_onExchangeRateTypeChanged");
}
void _onExchangeTypeChanged() {
updateRanges(shouldNotifyListeners: true).then(
(_) => updateEstimate(
shouldNotifyListeners: true,
reversed: reversed,
),
);
}
Future<void> updateRanges({required bool shouldNotifyListeners}) async {
if (exchange?.name == SimpleSwapExchange.exchangeName) {
reversed = false;
}
final _fromTicker = reversed ? toTicker : fromTicker;
final _toTicker = reversed ? fromTicker : toTicker;
if (_fromTicker == null || _toTicker == null) {
Logging.instance.log(
"Tried to $runtimeType.updateRanges where (from: $_fromTicker || to: $_toTicker) for: $exchange",
level: LogLevel.Info,
);
return;
}
final response = await exchange?.getRange(
_fromTicker,
_toTicker,
exchangeType == ExchangeRateType.fixed,
);
if (response?.value == null) {
Logging.instance.log(
"Tried to $runtimeType.updateRanges for: $exchange where response: $response",
level: LogLevel.Info,
);
return;
}
final range = response!.value!;
minAmount = range.min;
maxAmount = range.max;
debugPrint(
"updated range for: $exchange for $_fromTicker-$_toTicker: $range");
if (shouldNotifyListeners) {
notifyListeners();
}
}
Future<void> updateEstimate({
required bool shouldNotifyListeners,
required bool reversed,
}) async {
if (exchange?.name == SimpleSwapExchange.exchangeName) {
reversed = false;
}
final amount = reversed ? toAmount : fromAmount;
if (fromTicker == null ||
toTicker == null ||
amount == null ||
amount <= Decimal.zero) {
Logging.instance.log(
"Tried to $runtimeType.updateEstimate for: $exchange where (from: $fromTicker || to: $toTicker || amount: $amount)",
level: LogLevel.Info,
);
return;
}
final response = await exchange?.getEstimate(
fromTicker!,
toTicker!,
amount,
exchangeType == ExchangeRateType.fixed,
reversed,
);
if (response?.value == null) {
Logging.instance.log(
"Tried to $runtimeType.updateEstimate for: $exchange where response: $response",
level: LogLevel.Info,
);
return;
}
estimate = response!.value!;
if (reversed) {
fromAmount = estimate!.estimatedAmount;
} else {
toAmount = estimate!.estimatedAmount;
}
rate = (toAmount! / fromAmount!).toDecimal(scaleOnInfinitePrecision: 12);
debugPrint(
"updated estimate for: $exchange for $fromTicker-$toTicker: $estimate");
if (shouldNotifyListeners) {
notifyListeners();
}
}
void setOnError({
required void Function(String)? onError,
bool shouldNotifyListeners = false,
}) {
_onError = onError;
if (shouldNotifyListeners) {
notifyListeners();
}
}
Future<void> swap({FixedRateMarket? market}) async {
final Decimal? newToAmount = fromAmount;
final Decimal? newFromAmount = toAmount;
fromAmount = newFromAmount;
toAmount = newToAmount;
minAmount = null;
maxAmount = null;
if (exchangeType == ExchangeRateType.fixed &&
exchange?.name == ChangeNowExchange.exchangeName) {
await updateMarket(market, false);
} else {
final Currency? newTo = from;
final Currency? newFrom = to;
_to = newTo;
_from = newFrom;
await updateRanges(shouldNotifyListeners: false);
await updateEstimate(
shouldNotifyListeners: false,
reversed: reversed,
);
}
notifyListeners();
}
}