pwltr · Oct 9, 2026 · Oct 9, 2026 · Oct 9, 2026
diff --git a/Bitkit/Utilities/Bip21Utils.swift b/Bitkit/Utilities/Bip21Utils.swift
@@ -2,8 +2,6 @@ import Foundation
 
 /// Utility methods for BIP21 URI handling
 enum Bip21Utils {
-    private static let bip21Prefix = "bitcoin:"
-
     static func hardwareInvoice(address: String, amountSats: UInt64, message: String) -> String {
         var components = URLComponents()
         components.scheme = "bitcoin"
@@ -24,16 +22,4 @@ enum Bip21Utils {
         components.queryItems = queryItems.isEmpty ? nil : queryItems
         return components.string ?? "bitcoin:\(address)"
     }
-
-    /// Checks if a BIP21 URI is duplicated (contains multiple bitcoin: prefixes).
-    /// Workaround for https://github.com/synonymdev/bitkit-core/issues/63
-    /// - Parameter input: The string to check
-    /// - Returns: true if the input contains duplicated BIP21 URIs, false otherwise
-    static func isDuplicatedBip21(_ input: String) -> Bool {
-        let lowercased = input.lowercased()
-        guard let firstIndex = lowercased.range(of: bip21Prefix)?.upperBound else {
-            return false
-        }
-        return lowercased[firstIndex...].contains(bip21Prefix)
-    }
 }
diff --git a/Bitkit/Utilities/ClipboardPrompt.swift b/Bitkit/Utilities/ClipboardPrompt.swift
@@ -67,7 +67,6 @@ enum ClipboardPromptValidator {
         }
 
         let normalized = uri.removingLightningSchemes()
-        guard !Bip21Utils.isDuplicatedBip21(normalized) else { return false }
         // Only recognize these shapes here: fetching remote metadata must wait for the user's OK tap.
         if requiresNetworkResolution(normalized) {
             return true

diff --git a/Bitkit/Utilities/ShopPaymentRequest.swift b/Bitkit/Utilities/ShopPaymentRequest.swift
@@ -8,6 +8,16 @@ enum ScanHandlingScope {
 }
 
 enum ShopPaymentRequest {
+    static func decodingErrorToast(for error: Error) -> Toast? {
+        guard error is DecodingError else { return nil }
+        return Toast(
+            type: .error,
+            title: t("other__scan_err_decoding"),
+            description: t("other__scan__error__generic"),
+            accessibilityIdentifier: "InvalidAddressToast"
+        )
+    }
+
     static func isSupported(_ data: BitkitCore.Scanner) -> Bool {
         switch data {
         case .onChain, .lightning, .lnurlPay:

diff --git a/Bitkit/ViewModels/AppViewModel.swift b/Bitkit/ViewModels/AppViewModel.swift
@@ -638,15 +638,6 @@ extension AppViewModel {
             else {
                 throw ScanHandlingError.unsupportedRequest
             }
-            if Bip21Utils.isDuplicatedBip21(uri) {
-                toast(
-                    type: .error,
-                    title: t("other__scan_err_decoding"),
-                    description: t("other__scan__error__generic"),
-                    accessibilityIdentifier: "InvalidAddressToast"
-                )
-                return
-            }
             let data = try await decode(invoice: uri)
             try ensureScannedDataHandlingOwnership(handlingId, claimedContactPaymentContext: claimedContactPaymentContext)
             guard ShopPaymentRequest.isSupported(data) else { throw ScanHandlingError.unsupportedRequest }
@@ -668,17 +659,6 @@ extension AppViewModel {
             return
         }
 
-        // Workaround for duplicated BIP21 URIs (bitkit-core#63)
-        if scope == .unrestricted, Bip21Utils.isDuplicatedBip21(uri) {
-            toast(
-                type: .error,
-                title: t("other__scan_err_decoding"),
-                description: t("other__scan__error__generic"),
-                accessibilityIdentifier: "InvalidAddressToast"
-            )
-            return
-        }
-
         if PubkyAuthRequest.isProtocolURL(uri) {
             guard scope == .unrestricted else {
                 throw ScanHandlingError.pubkyAuthRequest
@@ -1179,15 +1159,6 @@ extension AppViewModel {
             return
         }
 
-        // Workaround for duplicated BIP21 URIs (bitkit-core#63)
-        if Bip21Utils.isDuplicatedBip21(normalized) {
-            guard currentSequence == manualEntryValidationSequence else { return }
-            manualEntryValidationResult = .invalid
-            isManualEntryInputValid = false
-            showValidationErrorToast(for: .invalid)
-            return
-        }
-
         if PubkyPublicKeyFormat.normalized(normalized) != nil {
             guard currentSequence == manualEntryValidationSequence else { return }
             if PaykitFeatureFlags.isUIEnabled {

diff --git a/Bitkit/Views/Shop/ShopMain.swift b/Bitkit/Views/Shop/ShopMain.swift
@@ -68,7 +68,16 @@ struct ShopMain: View {
                     sheetViewModel: sheets
                 )
             } catch {
-                app.toast(error)
+                if let toast = ShopPaymentRequest.decodingErrorToast(for: error) {
+                    app.toast(
+                        type: toast.type,
+                        title: toast.title,
+                        description: toast.description,
+                        accessibilityIdentifier: toast.accessibilityIdentifier
+                    )
+                } else {
+                    app.toast(error)
+                }
             }
         }
     }

diff --git a/BitkitTests/Bip21DecodingTests.swift b/BitkitTests/Bip21DecodingTests.swift
@@ -0,0 +1,100 @@
+@testable import Bitkit
+import BitkitCore
+import Combine
+import XCTest
+
+@MainActor
+final class Bip21DecodingTests: XCTestCase {
+    private let address = "bcrt1qr289x0fhg62672e8urudfnxnsr8tcax64xk2vk"
+
+    private var duplicatedURI: String {
+        "bitcoin:\(address)?amount=0.0000002&message=Bitkit" +
+            "bitcoin:\(address)?amount=0.0000003&message=Bitkit"
+    }
+
+    func testCoreRejectsDuplicateSingletonParameters() async {
+        for uri in [
+            duplicatedURI,
+            "bitcoin:\(address)?amount=0.000035&AMOUNT=0.00005",
+            "bitcoin:\(address)?label=first&LABEL=second",
+            "bitcoin:\(address)?message=first&Message=second",
+            "bitcoin:\(address)?pop=callback%3a&req-pop=callback%3a",
+        ] {
+            do {
+                _ = try await decode(invoice: uri)
+                XCTFail("Expected duplicate singleton parameters to fail: \(uri)")
+            } catch DecodingError.InvalidFormat {
+            } catch {
+                XCTFail("Unexpected error: \(error)")
+            }
+        }
+    }
+
+    func testCorePreservesBitcoinTextInQueryMetadata() async throws {
+        for (key, value) in [
+            ("message", "bitcoin:donation"),
+            ("label", "BITCOIN:donation"),
+            ("custom", "bitcoin:1BoatSLRHtKNngkdXEeobR76b53LETtpyT"),
+            ("message", "Why?"),
+        ] {
+            let data = try await decode(invoice: "bitcoin:\(address)?amount=0.000035&\(key)=\(value)")
+            guard case let .onChain(invoice) = data else {
+                return XCTFail("Expected an on-chain invoice")
+            }
+            XCTAssertEqual(invoice.address, address)
+            XCTAssertEqual(invoice.amountSatoshis, 3500)
+            XCTAssertEqual(invoice.params?[key], value)
+        }
+    }
+
+    func testShopDecodeFailureThrowsWithoutReplacingPreviousInvoice() async {
+        let app = AppViewModel()
+        app.scannedOnchainInvoice = OnChainInvoice(
+            address: address, amountSatoshis: 42, label: nil, message: "Previous invoice", params: [:]
+        )
+
+        do {
+            try await app.handleScannedData(duplicatedURI, scope: .paymentRequests)
+            XCTFail("Expected Shop decoding to throw instead of returning success")
+        } catch DecodingError.InvalidFormat {
+        } catch {
+            XCTFail("Unexpected error: \(error)")
+        }
+
+        XCTAssertEqual(app.scannedOnchainInvoice?.amountSatoshis, 42)
+        XCTAssertEqual(app.scannedOnchainInvoice?.message, "Previous invoice")
+        XCTAssertNil(app.scannedLightningInvoice)
+    }
+
+    func testValidBitcoinNoteReachesPaymentStateInEveryPaymentScope() async throws {
+        for scope: ScanHandlingScope in [.unrestricted, .paymentRequests, .onchainPayments] {
+            let app = AppViewModel()
+            try await app.handleScannedData(
+                "bitcoin:\(address)?amount=0.000035&message=bitcoin:donation",
+                scope: scope,
+                alternativeOnchainBalanceSats: 100_000
+            )
+            XCTAssertEqual(app.scannedOnchainInvoice?.address, address)
+            XCTAssertEqual(app.scannedOnchainInvoice?.amountSatoshis, 3500)
+            XCTAssertEqual(app.scannedOnchainInvoice?.message, "bitcoin:donation")
+        }
+    }
+
+    func testManualEntryUsesCoreValidation() async {
+        for (uri, expected): (String, ManualEntryValidationResult) in [
+            ("bitcoin:\(address)?amount=0.000035&message=bitcoin:donation", .valid),
+            (duplicatedURI, .invalid),
+        ] {
+            let app = AppViewModel()
+            let validated = expectation(description: "manual entry validated")
+            let subscription = app.$manualEntryValidationResult.dropFirst().sink { result in
+                XCTAssertEqual(result, expected)
+                validated.fulfill()
+            }
+            app.validateManualEntryInput(uri, savingsBalanceSats: 100_000, spendingBalanceSats: 0)
+            await fulfillment(of: [validated], timeout: 5)
+            XCTAssertEqual(app.isManualEntryInputValid, expected == .valid)
+            subscription.cancel()
+        }
+    }
+}
diff --git a/BitkitTests/Bip21UtilsTests.swift b/BitkitTests/Bip21UtilsTests.swift
@@ -29,51 +29,4 @@ final class Bip21UtilsTests: XCTestCase {
             "bitcoin:bcrt1qreceive?amount=0.00021&message=Hardware%20receive"
         )
     }
-
-    // MARK: - isDuplicatedBip21 Tests
-
-    func testIsDuplicatedBip21_ReturnsFalseForSingleValidBIP21URI() {
-        let input = "bitcoin:bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq?amount=0.001&message=Bitkit"
-        XCTAssertFalse(Bip21Utils.isDuplicatedBip21(input))
-    }
-
-    func testIsDuplicatedBip21_ReturnsTrueWhenBIP21URIIsDuplicated() {
-        let first = "bitcoin:bcrt1qr289x0fhg62672e8urudfnxnsr8tcax64xk2vk?amount=0.0000002&message=Bitkit"
-        let second = "bitcoin:bcrt1qr289x0fhg62672e8urudfnxnsr8tcax64xk2vk?amount=0.0000003&message=Bitkit"
-        let input = first + second
-        XCTAssertTrue(Bip21Utils.isDuplicatedBip21(input))
-    }
-
-    func testIsDuplicatedBip21_HandlesCaseInsensitiveBitcoinPrefix() {
-        let first = "BITCOIN:bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq?amount=0.001"
-        let second = "bitcoin:bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq?amount=0.002"
-        let input = first + second
-        XCTAssertTrue(Bip21Utils.isDuplicatedBip21(input))
-    }
-
-    func testIsDuplicatedBip21_ReturnsFalseForNonBitcoinURIs() {
-        let input = "lnbc500n1p3k9v3pp5kzmj..."
-        XCTAssertFalse(Bip21Utils.isDuplicatedBip21(input))
-    }
-
-    func testIsDuplicatedBip21_ReturnsFalseForEmptyString() {
-        XCTAssertFalse(Bip21Utils.isDuplicatedBip21(""))
-    }
-
-    func testIsDuplicatedBip21_HandlesMixedCaseDuplicatedURIs() {
-        let first = "Bitcoin:bc1qaddr1?amount=0.001"
-        let second = "BITCOIN:bc1qaddr2?amount=0.002"
-        let input = first + second
-        XCTAssertTrue(Bip21Utils.isDuplicatedBip21(input))
-    }
-
-    func testIsDuplicatedBip21_ReturnsFalseForPlainBitcoinAddress() {
-        let input = "bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq"
-        XCTAssertFalse(Bip21Utils.isDuplicatedBip21(input))
-    }
-
-    func testIsDuplicatedBip21_ReturnsFalseForSingleBIP21WithLightningParam() {
-        let input = "bitcoin:bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq?lightning=lnbc500n1p3k9v3pp5kzmj"
-        XCTAssertFalse(Bip21Utils.isDuplicatedBip21(input))
-    }
 }
diff --git a/BitkitTests/ClipboardPromptValidatorTests.swift b/BitkitTests/ClipboardPromptValidatorTests.swift
@@ -89,13 +89,26 @@ final class ClipboardPromptValidatorTests: XCTestCase {
         }
     }
 
-    func testDuplicateBip21IsRejectedBeforeCandidateRecognition() async {
-        let supported = await ClipboardPromptValidator.isSupportedURI(
-            "bitcoin:bitcoin:invalid?lightning=lnurl1qqqqqq", ownPublicKey: nil, contacts: []
-        ) { _ in
-            XCTFail("Duplicated BIP21 must be rejected before decoding")
-            return true
+    func testBip21ValidationUsesDecoderResult() async {
+        let uri = "bitcoin:mipcBbFg9gMiCh81Kj8tqqdgoZub1ZJRfn?message=bitcoin:donation"
+        for decoderResult in [false, true] {
+            var decodeCount = 0
+            let supported = await ClipboardPromptValidator.isSupportedURI(uri, ownPublicKey: nil, contacts: []) {
+                decodeCount += 1
+                XCTAssertEqual($0, uri)
+                return decoderResult
+            }
+            XCTAssertEqual(decodeCount, 1)
+            XCTAssertEqual(supported, decoderResult)
         }
+    }
+
+    func testDuplicateBip21IsRejectedByCoreDecoder() async {
+        let first = "bitcoin:bcrt1qr289x0fhg62672e8urudfnxnsr8tcax64xk2vk?amount=0.0000002&message=Bitkit"
+        let second = "bitcoin:bcrt1qr289x0fhg62672e8urudfnxnsr8tcax64xk2vk?amount=0.0000003&message=Bitkit"
+        let supported = await ClipboardPromptValidator.isSupportedURI(
+            first + second, ownPublicKey: nil, contacts: []
+        )
         XCTAssertFalse(supported)
     }
 

diff --git a/BitkitTests/ShopPaymentRequestTests.swift b/BitkitTests/ShopPaymentRequestTests.swift
@@ -4,6 +4,22 @@ import XCTest
 
 @MainActor
 final class ShopPaymentRequestTests: XCTestCase {
+    func testDecodingErrorsUseLocalizedScanToast() throws {
+        for error: DecodingError in [.InvalidFormat, .InvalidAmount, .InvalidAddress, .RequestFailed] {
+            let toast = try XCTUnwrap(ShopPaymentRequest.decodingErrorToast(for: error))
+            XCTAssertEqual(toast.type, .error)
+            XCTAssertEqual(toast.title, t("other__scan_err_decoding"))
+            XCTAssertEqual(toast.description, t("other__scan__error__generic"))
+            XCTAssertEqual(toast.accessibilityIdentifier, "InvalidAddressToast")
+        }
+    }
+
+    func testNonDecodingErrorsKeepExistingErrorHandling() {
+        for error in [CancellationError(), ScanHandlingError.unsupportedRequest, ScanHandlingError.pubkyAuthRequest] as [Error] {
+            XCTAssertNil(ShopPaymentRequest.decodingErrorToast(for: error))
+        }
+    }
+
     func testLightningInvoiceIsSupported() {
         XCTAssertTrue(ShopPaymentRequest.isSupported(.lightning(invoice: lightningInvoice)))
     }

diff --git a/changelog.d/next/909.fixed.md b/changelog.d/next/909.fixed.md
@@ -0,0 +1 @@
+Fixed payment URI validation to accept Bitcoin links in notes and reject ambiguous payment requests with localized errors instead of reopening a previous payment.
diff --git a/journeys/send/README.md b/journeys/send/README.md
@@ -0,0 +1,9 @@
+# Send
+
+`bip21-core-validation.xml` is shared with Android, with identical actions and fixtures. It requires a released bitkit-core SDK containing [PR #151](https://github.com/synonymdev/bitkit-core/pull/151); the current 0.5.18 dependency cannot satisfy its duplicate-key checks. Keep the adoption PR in draft until that dependency is bumped and the journey passes.
+
+Deliver each `Open bitcoin:...` action with `xcrun simctl openurl <simulator-udid> "<uri>"`, replacing XML `&amp;` with `&` in the actual URI. Inspect errors immediately. Use XcodeBuildMCP snapshots for payment state and screenshots for transient error toasts.
+
+Use an onboarded regtest wallet with at least 100,000 sats in Savings and Quickpay disabled. The fixture address is not a destination to pay; close every payment sheet without confirming payment.
+
+The native-binding tests also cover labels, proof-of-payment aliases and question marks in notes. App tests cover manual entry and the Shop rejection path; a malformed `payment_intent` from the real third-party Shop cannot be generated through this journey environment. Automatic clipboard prompting additionally has a manual check because arbitrary OS clipboard injection is not listed in the Capabilities table.
diff --git a/journeys/send/bip21-core-validation.xml b/journeys/send/bip21-core-validation.xml
@@ -0,0 +1,17 @@
+<journey name="bip21 core validation">
+  <description>Preconditions: an onboarded English-language regtest wallet with at least 100,000 sats in Savings, Quickpay disabled, and a bitkit-core release containing PR #151. Do not pay any fixture. Open each bitcoin: link through the platform's external-URI delivery command described in this suite's README. This checks that the native decoder rejects ambiguous payments while accepting bitcoin: text as metadata.</description>
+  <actions>
+    <action>Open bitcoin:bcrt1qr289x0fhg62672e8urudfnxnsr8tcax64xk2vk?amount=0.000035&amp;message=bitcoin:donation</action>
+    <action>Verify Send shows the recipient bcrt1qr289x0fhg62672e8urudfnxnsr8tcax64xk2vk, an amount of 3,500 sats, and the note bitcoin:donation without a decoding error</action>
+    <action>Close Send without paying</action>
+    <action>Open bitcoin:bcrt1qr289x0fhg62672e8urudfnxnsr8tcax64xk2vk?amount=0.0000002&amp;message=Bitkitbitcoin:bcrt1qr289x0fhg62672e8urudfnxnsr8tcax64xk2vk?amount=0.0000003&amp;message=Bitkit</action>
+    <action>Verify a decoding error appears and Send does not open with the previous payment</action>
+    <action>Open bitcoin:bcrt1qr289x0fhg62672e8urudfnxnsr8tcax64xk2vk?amount=0.000035&amp;AMOUNT=0.00005</action>
+    <action>Verify a decoding error appears and no payment sheet opens</action>
+    <action>Open bitcoin:bcrt1qr289x0fhg62672e8urudfnxnsr8tcax64xk2vk?message=first&amp;Message=second</action>
+    <action>Verify a decoding error appears and no payment sheet opens</action>
+    <action>Open bitcoin:bcrt1qr289x0fhg62672e8urudfnxnsr8tcax64xk2vk?amount=0.000035&amp;custom=bitcoin:1BoatSLRHtKNngkdXEeobR76b53LETtpyT</action>
+    <action>Verify Send still shows bcrt1qr289x0fhg62672e8urudfnxnsr8tcax64xk2vk as the recipient and 3,500 sats as the amount</action>
+    <action>Close Send without paying</action>
+  </actions>
+</journey>
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		Fixed payment URI validation to accept Bitcoin links in notes and reject ambiguous payment requests with localized errors instead of reopening a previous payment.