connect toggle to preferences and use value in parent buy form

lib/pages/buy_view/buy_form.dart

@@ -42,6 +42,8 @@ class _BuyFormState extends ConsumerState<BuyForm> {
   final FocusNode _fiatFocusNode = FocusNode();
   final FocusNode _cryptoFocusNode = FocusNode();
 
+  bool buyWithFiat = true;
+
   void fiatFieldOnChanged(String value) async {
     if (_fiatFocusNode.hasFocus) {
       final newFromAmount = Decimal.tryParse(value);
@@ -470,6 +472,9 @@ class _BuyFormState extends ConsumerState<BuyForm> {
   Widget build(BuildContext context) {
     debugPrint("BUILD: $runtimeType");
 
+    buyWithFiat = ref.watch(
+        prefsChangeNotifierProvider.select((value) => value.buyWithFiat));
+
     return Column(
       mainAxisSize: MainAxisSize.min,
       crossAxisAlignment: CrossAxisAlignment.stretch,
@@ -557,7 +562,7 @@ class _BuyFormState extends ConsumerState<BuyForm> {
           mainAxisAlignment: MainAxisAlignment.spaceBetween,
           children: [
             Text(
-              "Enter amount",
+              buyWithFiat ? "Enter amount" : "Enter crypto amount",
               style: STextStyles.itemSubtitle(context).copyWith(
                 color: Theme.of(context).extension<StackColors>()!.textDark3,
               ),

lib/pages/buy_view/sub_widgets/fiat_crypto_toggle.dart

@@ -1,57 +1,29 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:stackwallet/providers/providers.dart';
 import 'package:stackwallet/utilities/util.dart';
 import 'package:stackwallet/widgets/custom_buttons/blue_text_button.dart';
 
 class FiatCryptoToggle extends ConsumerWidget {
   const FiatCryptoToggle({
     Key? key,
-    // this.onChanged,
   }) : super(key: key);
 
-  // final void Function(ExchangeRateType)? onChanged;
-
   @override
   Widget build(BuildContext context, WidgetRef ref) {
     debugPrint("BUILD: $runtimeType");
     final isDesktop = Util.isDesktop;
 
-    // final estimated = ref.watch(prefsChangeNotifierProvider
-    //         .select((value) => value.exchangeRateType)) ==
-    //     ExchangeRateType.estimated;
+    final buyWithFiat = ref.watch(
+        prefsChangeNotifierProvider.select((value) => value.buyWithFiat));
 
-    // return Toggle(
-    //   onValueChanged: (value) {
-    //     //   if (!estimated) {
-    //     //     ref.read(prefsChangeNotifierProvider).exchangeRateType =
-    //     //         ExchangeRateType.estimated;
-    //     //     onChanged?.call(ExchangeRateType.estimated);
-    //     //   } else {
-    //     //     onChanged?.call(ExchangeRateType.fixed);
-    //     //   }
-    //   },
-    //   isOn: true,
-    //   onColor: Theme.of(context).extension<StackColors>()!.textFieldDefaultBG,
-    //   offColor: isDesktop
-    //       ? Theme.of(context).extension<StackColors>()!.buttonBackSecondary
-    //       : Theme.of(context).extension<StackColors>()!.popupBG,
-    //   decoration: BoxDecoration(
-    //     borderRadius: BorderRadius.circular(
-    //       Constants.size.circularBorderRadius,
-    //     ),
-    //   ),
-    //   onIcon: Assets.svg.lockOpen,
-    //   onText: "Estimate rate",
-    //   offIcon: Assets.svg.lock,
-    //   offText: "Fixed rate",
-    // );
     return BlueTextButton(
-      text: "Use crypto amount",
+      text: buyWithFiat ? "Use crypto amount" : "Use fiat amount",
       textSize: 14,
       onTap: () {
-        // Navigator.of(context).pushNamed(
-        //   ForgotPasswordDesktopView.routeName,
-        // );
+        final buyWithFiat = ref.read(prefsChangeNotifierProvider).buyWithFiat;
+        ref.read(prefsChangeNotifierProvider).buyWithFiat = !buyWithFiat;
+        // Navigator.of(context).pop();
       },
     );
   }

lib/utilities/prefs.dart

@@ -38,6 +38,7 @@ class Prefs extends ChangeNotifier {
       _startupWalletId = await _getStartupWalletId();
       _externalCalls = await _getHasExternalCalls();
       _familiarity = await _getHasFamiliarity();
+      _buyWithFiat = await _getBuyWithFiat();
 
       _initialized = true;
     }
@@ -350,6 +351,25 @@ class Prefs extends ChangeNotifier {
         0;
   }
 
+  // buy with fiat (default) or crypto
+  bool _buyWithFiat = true;
+  bool get buyWithFiat => _buyWithFiat;
+
+  set buyWithFiat(bool buyWithFiat) {
+    if (this.buyWithFiat != buyWithFiat) {
+      DB.instance.put<dynamic>(
+          boxName: DB.boxNamePrefs, key: "buyWithFiat", value: buyWithFiat);
+      _buyWithFiat = buyWithFiat;
+      notifyListeners();
+    }
+  }
+
+  Future<bool> _getBuyWithFiat() async {
+    return await DB.instance.get<dynamic>(
+            boxName: DB.boxNamePrefs, key: "buyWithFiat") as bool? ??
+        true;
+  }
+
   // show testnet coins
 
   bool _showTestNetCoins = false;