Extend shielding state (#1322)

- This adds `ShieldState.Shielded` that helps us keep the correct UI state of the Transparent funds widget after the user starts shielding action
- This also brings little UI improvement in PrimaryButton sizing

ui-design-lib/src/main/java/co/electriccoin/zcash/ui/design/component/Button.kt

@@ -86,7 +86,7 @@ fun PrimaryButton(
             horizontal = ZcashTheme.dimens.spacingNone,
             vertical = ZcashTheme.dimens.spacingSmall
         ),
-    contentPaddingValues: PaddingValues = PaddingValues(all = 15.dp)
+    contentPaddingValues: PaddingValues = PaddingValues(all = 15.5.dp)
 ) {
     Button(
         shape = RectangleShape,

ui-lib/src/main/java/co/electriccoin/zcash/ui/screen/balances/AndroidBalances.kt

@@ -8,12 +8,14 @@ import androidx.compose.runtime.Composable
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.rememberCoroutineScope
 import androidx.compose.runtime.saveable.rememberSaveable
+import androidx.compose.ui.platform.LocalContext
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import cash.z.ecc.android.sdk.SdkSynchronizer
 import cash.z.ecc.android.sdk.Synchronizer
 import cash.z.ecc.android.sdk.model.UnifiedSpendingKey
 import cash.z.ecc.android.sdk.model.Zatoshi
 import co.electriccoin.zcash.spackle.Twig
+import co.electriccoin.zcash.ui.R
 import co.electriccoin.zcash.ui.common.model.WalletRestoringState
 import co.electriccoin.zcash.ui.common.model.WalletSnapshot
 import co.electriccoin.zcash.ui.common.viewmodel.CheckUpdateViewModel
@@ -85,6 +87,8 @@ internal fun WrapBalances(
 ) {
     val scope = rememberCoroutineScope()
 
+    val context = LocalContext.current
+
     // To show information about the app update, if available
     val isUpdateAvailable =
         checkUpdateViewModel.updateInfo.collectAsStateWithLifecycle().value.let {
@@ -94,15 +98,10 @@ internal fun WrapBalances(
     val isFiatConversionEnabled = ConfigurationEntries.IS_FIAT_CONVERSION_ENABLED.getValue(RemoteConfig.current)
 
     val (shieldState, setShieldState) =
-        rememberSaveable(stateSaver = ShieldState.Saver) {
+        rememberSaveable(stateSaver = ShieldState.Saver) { mutableStateOf(ShieldState.None) }
-            mutableStateOf(
+
-                if (walletSnapshot?.hasTransparentFunds == true) {
+    // Keep the state always up-to-date with the latest transparent balance
-                    ShieldState.Available
+    setShieldState(updateTransparentBalanceState(shieldState, walletSnapshot))
-                } else {
-                    ShieldState.None
-                }
-            )
-        }
 
     val (isShowingErrorDialog, setShowErrorDialog) = rememberSaveable { mutableStateOf(false) }
 
@@ -145,10 +144,12 @@ internal fun WrapBalances(
                             transparentReceiver = null
                         )
                     }.onSuccess { newProposal ->
-                        Twig.debug { "Shielding proposal result: ${newProposal?.toPrettyString()}" }
+                        Twig.info { "Shielding proposal result: ${newProposal?.toPrettyString()}" }
 
                         if (newProposal == null) {
-                            showShieldingError(null)
+                            showShieldingError(
+                                context.getString(R.string.balances_shielding_dialog_error_below_threshold)
+                            )
                         } else {
                             val result =
                                 createTransactionsViewModel.runCreateTransactions(
@@ -159,7 +160,7 @@ internal fun WrapBalances(
                             when (result) {
                                 SubmitResult.Success -> {
                                     Twig.info { "Shielding transaction done successfully" }
-                                    setShieldState(ShieldState.None)
+                                    setShieldState(ShieldState.Shielded)
                                     // Triggering transaction history refresh to be notified about the newly created
                                     // transaction asap
                                     (synchronizer as SdkSynchronizer).refreshTransactions()
@@ -188,3 +189,21 @@ internal fun WrapBalances(
         )
     }
 }
+
+fun updateTransparentBalanceState(
+    currentShieldState: ShieldState,
+    walletSnapshot: WalletSnapshot?
+): ShieldState {
+    return when {
+        (walletSnapshot == null) -> {
+            currentShieldState
+        }
+        (
+            walletSnapshot.transparentBalance >= Zatoshi(DEFAULT_SHIELDING_THRESHOLD) &&
+                currentShieldState.isEnabled()
+        ) -> ShieldState.Available
+        else -> {
+            currentShieldState
+        }
+    }
+}

ui-lib/src/main/java/co/electriccoin/zcash/ui/screen/balances/model/ShieldState.kt

@@ -9,12 +9,17 @@ sealed class ShieldState {
 
     data object Running : ShieldState()
 
+    data object Shielded : ShieldState()
+
     data class Failed(val error: String) : ShieldState()
 
+    fun isEnabled() = this != Running && this !is Failed && this != Shielded
+
     companion object {
         private const val TYPE_NONE = "none" // $NON-NLS
         private const val TYPE_AVAILABLE = "available" // $NON-NLS
         private const val TYPE_RUNNING = "running" // $NON-NLS
+        private const val TYPE_SHIELDED = "shielded" // $NON-NLS
         private const val TYPE_FAILED = "failed" // $NON-NLS
         private const val KEY_TYPE = "type" // $NON-NLS
 
@@ -34,6 +39,7 @@ sealed class ShieldState {
                                     TYPE_NONE -> None
                                     TYPE_AVAILABLE -> Available
                                     TYPE_RUNNING -> Running
+                                    TYPE_SHIELDED -> Shielded
                                     TYPE_FAILED -> Failed((it[KEY_ERROR] as String))
                                     else -> null
                                 }
@@ -48,6 +54,7 @@ sealed class ShieldState {
                 None -> saverMap[KEY_TYPE] = TYPE_NONE
                 Available -> saverMap[KEY_TYPE] = TYPE_AVAILABLE
                 Running -> saverMap[KEY_TYPE] = TYPE_RUNNING
+                Shielded -> saverMap[KEY_TYPE] = TYPE_SHIELDED
                 is Failed -> {
                     saverMap[KEY_TYPE] = TYPE_FAILED
                     saverMap[KEY_ERROR] = this.error

ui-lib/src/main/res/ui/balances/values/strings.xml

@@ -33,4 +33,5 @@
     <string name="balances_shielding_dialog_error_title">Failed to shield funds</string>
     <string name="balances_shielding_dialog_error_text">Error: The attempt to shield the transparent funds failed. Try it again, please.</string>
     <string name="balances_shielding_dialog_error_btn">OK</string>
+    <string name="balances_shielding_dialog_error_below_threshold">The current transparent balance is zero or below the allowed shielding limit.</string>
 </resources>