[Woo POS][Barcodes] Timeout a partial scan with no terminating character (#15952)

Author: staskus

WooCommerce/Classes/POS/Models/Cart+BarcodeScanError.swift

@@ -121,9 +121,9 @@ extension PointOfSaleBarcodeScanError {
         )
 
         static let incompleteScan = NSLocalizedString(
-            "pointOfSale.barcodeScan.error.incompleteScan",
-            value: "Partial barcode scan",
-            comment: "Error message shown when scan is incomplete."
+            "pointOfSale.barcodeScan.error.incompleteScan.2",
+            value: "The scanner did not send an end-of-line character",
+            comment: "Error message shown when scanner times out without sending end-of-line character."
         )
 
         static let parsingError = NSLocalizedString(

WooCommerce/Classes/POS/Presentation/Barcode Scanning/GameControllerBarcodeParser.swift

@@ -15,6 +15,7 @@ final class GameControllerBarcodeParser {
     private var buffer = ""
     private var lastKeyPressTime: Date?
     private var scanStartTime: Date?
+    private var timeoutTimer: Timer?
 
     init(configuration: HIDBarcodeParserConfiguration,
          onScan: @escaping (HIDBarcodeParserResult) -> Void,
@@ -49,6 +50,7 @@ final class GameControllerBarcodeParser {
             }
 
             buffer.append(character)
+            scheduleTimeoutTimer()
         }
     }
 
@@ -186,6 +188,31 @@ final class GameControllerBarcodeParser {
         buffer = ""
         lastKeyPressTime = nil
         scanStartTime = nil
+        cancelTimeoutTimer()
+    }
+
+    private func scheduleTimeoutTimer() {
+        cancelTimeoutTimer()
+        timeoutTimer = timeProvider.scheduleTimer(
+            timeInterval: configuration.maximumInterCharacterTime,
+            target: self,
+            selector: #selector(handleTimeoutExpiry)
+        )
+    }
+
+    private func cancelTimeoutTimer() {
+        timeoutTimer?.invalidate()
+        timeoutTimer = nil
+    }
+
+    @objc private func handleTimeoutExpiry() {
+        guard !buffer.isEmpty else { return }
+
+        let scanDurationMs = calculateScanDurationMs()
+        let result = HIDBarcodeParserResult.failure(error: HIDBarcodeParserError.timedOut(barcode: buffer), scanDurationMs: scanDurationMs)
+
+        onScan(result)
+        resetScan()
     }
 
     private func calculateScanDurationMs() -> Int {
@@ -194,6 +221,7 @@ final class GameControllerBarcodeParser {
     }
 
     private func processScan() {
+        cancelTimeoutTimer()
         checkForTimeoutBetweenKeystrokes()
         let scanDurationMs = calculateScanDurationMs()
 

WooCommerce/Classes/POS/Presentation/Barcode Scanning/TimeProvider.swift

@@ -2,10 +2,15 @@ import Foundation
 
 protocol TimeProvider {
     func now() -> Date
+    func scheduleTimer(timeInterval: TimeInterval, target: Any, selector: Selector) -> Timer
 }
 
 struct DefaultTimeProvider: TimeProvider {
     func now() -> Date {
         Date()
     }
+
+    func scheduleTimer(timeInterval: TimeInterval, target: Any, selector: Selector) -> Timer {
+        return Timer.scheduledTimer(timeInterval: timeInterval, target: target, selector: selector, userInfo: nil, repeats: false)
+    }
 }