(ios) Fix several UI issues (#493)

- Fixing compiler issues (latest lightning-kmp changes)

- Hide fee bumping button in irrelevant cases (funding 
and closing). Fixes #488.

- Don't allow users to send on-chain transactions with sat/vByte
below minimumFee

phoenix-ios/phoenix-ios/Localizable.xcstrings

@@ -8229,6 +8229,12 @@
           }
         }
       }
+    },
+    "Feerate below minimum allowed by mempool: %@" : {
+
+    },
+    "Feerate below minimum allowed by mempool." : {
+
     },
     "Fees" : {
       "comment" : "Label in SummaryInfoGrid",

phoenix-ios/phoenix-ios/views/inspect/CpfpView.swift

@@ -26,7 +26,8 @@ struct MinerFeeCPFP {
 }
 
 enum CpfpError: Error {
-	case feeTooLow
+	case feeBelowMinimum
+	case feeNotIncreased
 	case noChannels
 	case errorThrown(message: String)
 	case executeError(problem: SpliceOutProblem)
@@ -180,7 +181,7 @@ struct CpfpView: View {
 			minerFeeFormula()
 				.padding(.bottom)
 
-			payButton()
+			footer()
 		}
 		.padding(.horizontal, 40)
 	}
@@ -387,7 +388,7 @@ struct CpfpView: View {
 	}
 
 	@ViewBuilder
-	func payButton() -> some View {
+	func footer() -> some View {
 
 		VStack(alignment: HorizontalAlignment.center, spacing: 10) {
 
@@ -412,7 +413,13 @@ struct CpfpView: View {
 
 				Group {
 					switch cpfpError {
-					case .feeTooLow:
+					case .feeBelowMinimum:
+						if let mrr = mempoolRecommendedResponse {
+							Text("Feerate below minimum allowed by mempool: \(satsPerByteString(mrr.minimumFee))")
+						} else {
+							Text("Feerate below minimum allowed by mempool.")
+						}
+					case .feeNotIncreased:
 						Text(
 							"""
 							This feerate is below what your transactions are already using. \
@@ -527,15 +534,19 @@ struct CpfpView: View {
 		}
 
 		let doubleValue = mempoolRecommendedResponse.feeForPriority(priority)
-
+		let stringValue = satsPerByteString(doubleValue)
+
+		return (doubleValue, stringValue)
+	}
+
+	func satsPerByteString(_ value: Double) -> String {
+
 		let nf = NumberFormatter()
 		nf.numberStyle = .decimal
 		nf.minimumFractionDigits = 0
 		nf.maximumFractionDigits = 1
 
-		let stringValue = nf.string(from: NSNumber(value: doubleValue)) ?? "?"
-
-		return (doubleValue, stringValue)
+		return nf.string(from: NSNumber(value: value)) ?? "?"
 	}
 
 	func satsPerByteString(_ priority: MinerFeePriority) -> String {
@@ -619,26 +630,29 @@ struct CpfpView: View {
 	func satsPerByteChanged() {
 		log.trace("satsPerByteChanged(): \(satsPerByte)")
 
+		minerFeeInfo = nil
 		guard
 			let satsPerByte_number = try? parsedSatsPerByte.get(),
 			let peer = Biz.business.peerManager.peerStateValue()
 		else {
-			minerFeeInfo = nil
 			return
 		}
 
+		if let mrr = mempoolRecommendedResponse, mrr.minimumFee > satsPerByte_number.doubleValue {
+			cpfpError = .feeBelowMinimum
+			return
+		}
+		cpfpError = nil
+
 		let originalSatsPerByte = satsPerByte
 
 		let satsPerByte_satoshi = Bitcoin_kmpSatoshi(sat: satsPerByte_number.int64Value)
 		let effectiveFeerate = Lightning_kmpFeeratePerByte(feerate: satsPerByte_satoshi)
 		let effectiveFeeratePerKw = Lightning_kmpFeeratePerKw(feeratePerByte: effectiveFeerate)
 
-		cpfpError = nil
-		minerFeeInfo = nil
-
 		Task { @MainActor in
 
-			var pair: KotlinPair<Lightning_kmpFeeratePerKw, Bitcoin_kmpSatoshi>? = nil
+			var pair: KotlinPair<Lightning_kmpFeeratePerKw, Lightning_kmpChannelCommand.CommitmentSpliceFees>? = nil
 			do {
 				pair = try await peer.estimateFeeForSpliceCpfp(
 					channelId: onChainPayment.channelId,
@@ -658,7 +672,8 @@ struct CpfpView: View {
 				let cpfpFeeratePerKw: Lightning_kmpFeeratePerKw = pair.first!
 				let cpfpFeerate = Lightning_kmpFeeratePerByte(feeratePerKw: cpfpFeeratePerKw)
 
-				let minerFee: Bitcoin_kmpSatoshi = pair.second!
+				let spliceFees: Lightning_kmpChannelCommand.CommitmentSpliceFees = pair.second!
+				let minerFee: Bitcoin_kmpSatoshi = spliceFees.miningFee
 
 				// From the docs (in lightning-kmp):
 				//
@@ -679,8 +694,8 @@ struct CpfpView: View {
 						minerFee: minerFee
 					)
 				} else {
-					log.error("Error: peer.estimateFeeForSpliceCpfp() => too low")
-					self.cpfpError = .feeTooLow
+					log.error("Error: peer.estimateFeeForSpliceCpfp() => fee not increased")
+					self.cpfpError = .feeNotIncreased
 				}
 
 			} else {
@@ -696,6 +711,9 @@ struct CpfpView: View {
 
 		// The UI will change, so we need to reset the geometry measurements
 		priorityBoxWidth = nil
+
+		// Might need to display an error (if minimumFee increased)
+		satsPerByteChanged()
 	}
 
 	func executePayment() {

phoenix-ios/phoenix-ios/views/inspect/SummaryView.swift

@@ -324,7 +324,7 @@ struct SummaryView: View {
 					}
 				} // </confirmationDialog>
 
-				if confirmations == 0 {
+				if confirmations == 0 && supportsBumpFee(onChainPayment) {
 					NavigationLink(destination: cpfpView(onChainPayment)) {
 						Label {
 							Text("Accelerate transaction")
@@ -651,6 +651,15 @@ struct SummaryView: View {
 		}
 	}
 
+	func supportsBumpFee(_ onChainPayment: Lightning_kmpOnChainOutgoingPayment) -> Bool {
+
+		switch onChainPayment {
+			case is Lightning_kmpSpliceOutgoingPayment     : return true
+			case is Lightning_kmpSpliceCpfpOutgoingPayment : return true
+			default                                        : return false
+		}
+	}
+
 	// --------------------------------------------------
 	// MARK: Tasks
 	// --------------------------------------------------

phoenix-ios/phoenix-ios/views/send/MinerFeeSheet.swift

@@ -24,6 +24,7 @@ struct MinerFeeSheet: View {
 	@Binding var mempoolRecommendedResponse: MempoolRecommendedResponse?
 
 	@State var explicitlySelectedPriority: MinerFeePriority? = nil
+	@State var feeBelowMinimum: Bool = false
 
 	@Environment(\.colorScheme) var colorScheme: ColorScheme
 	@EnvironmentObject var smartModalState: SmartModalState
@@ -296,16 +297,28 @@ struct MinerFeeSheet: View {
 	@ViewBuilder
 	func footer() -> some View {
 
-		HStack(alignment: VerticalAlignment.center, spacing: 0) {
-			Spacer()
+		VStack(alignment: HorizontalAlignment.center, spacing: 10) {
+
 			Button {
 				reviewTransactionButtonTapped()
 			} label: {
 				Text("Review Transaction")
 			}
 			.font(.title3)
 			.disabled(minerFeeInfo == nil)
-			Spacer()
+
+			if feeBelowMinimum {
+				Group {
+					if let mrr = mempoolRecommendedResponse {
+						Text("Feerate below minimum allowed by mempool: \(satsPerByteString(mrr.minimumFee))")
+					} else {
+						Text("Feerate below minimum allowed by mempool.")
+					}
+				}
+				.font(.callout)
+				.foregroundColor(.appNegative)
+				.multilineTextAlignment(.center)
+			}
 		}
 		.padding()
 		.padding(.top)
@@ -348,15 +361,19 @@ struct MinerFeeSheet: View {
 		}
 
 		let doubleValue = mempoolRecommendedResponse.feeForPriority(priority)
-
+		let stringValue = satsPerByteString(doubleValue)
+
+		return (doubleValue, stringValue)
+	}
+
+	func satsPerByteString(_ value: Double) -> String {
+
 		let nf = NumberFormatter()
 		nf.numberStyle = .decimal
 		nf.minimumFractionDigits = 0
 		nf.maximumFractionDigits = 1
 
-		let stringValue = nf.string(from: NSNumber(value: doubleValue)) ?? "?"
-
-		return (doubleValue, stringValue)
+		return nf.string(from: NSNumber(value: value)) ?? "?"
 	}
 
 	func satsPerByteString(_ priority: MinerFeePriority) -> String {
@@ -440,23 +457,29 @@ struct MinerFeeSheet: View {
 	func satsPerByteChanged() {
 		log.trace("satsPerByteChanged(): \(satsPerByte)")
 
+		minerFeeInfo = nil
 		guard
 			let satsPerByte_number = try? parsedSatsPerByte.get(),
 			let peer = Biz.business.peerManager.peerStateValue(),
 			let scriptBytes = Parser.shared.addressToPublicKeyScript(chain: Biz.business.chain, address: btcAddress)
 		else {
-			minerFeeInfo = nil
 			return
 		}
 
+		if let mrr = mempoolRecommendedResponse, mrr.minimumFee > satsPerByte_number.doubleValue {
+			feeBelowMinimum = true
+			return
+		} else {
+			feeBelowMinimum = false
+		}
+
 		let originalSatsPerByte = satsPerByte
 		let scriptVector = Bitcoin_kmpByteVector(bytes: scriptBytes)
 
 		let satsPerByte_satoshi = Bitcoin_kmpSatoshi(sat: satsPerByte_number.int64Value)
 		let feePerByte = Lightning_kmpFeeratePerByte(feerate: satsPerByte_satoshi)
 		let feePerKw = Lightning_kmpFeeratePerKw(feeratePerByte: feePerByte)
 
-		minerFeeInfo = nil
 		Task { @MainActor in
 			do {
 				let pair = try await peer.estimateFeeForSpliceOut(
@@ -467,13 +490,13 @@ struct MinerFeeSheet: View {
 
 				if let pair = pair,
 				   let updatedFeePerKw: Lightning_kmpFeeratePerKw = pair.first,
-				   let fee: Bitcoin_kmpSatoshi = pair.second
+				   let fees: Lightning_kmpChannelCommand.CommitmentSpliceFees = pair.second
 				{
 					if self.satsPerByte == originalSatsPerByte {
 						self.minerFeeInfo = MinerFeeInfo(
 							pubKeyScript: scriptVector,
 							feerate: updatedFeePerKw,
-							minerFee: fee
+							minerFee: fees.miningFee
 						)
 					}
 				} else {
@@ -492,6 +515,9 @@ struct MinerFeeSheet: View {
 
 		// The UI will change, so we need to reset the geometry measurements
 		priorityBoxWidth = nil
+
+		// Might need to display an error (if minimumFee increased)
+		satsPerByteChanged()
 	}
 
 	func closeButtonTapped() {