comboctl-main: Check for unchanging screen type in navigateToRTScreen()

Signed-off-by: Carlos Rafael Giani <crg7475@mailbox.org>

pump/combov2/comboctl/src/commonMain/kotlin/info/nightscout/comboctl/main/RTNavigation.kt

@@ -986,6 +986,7 @@ suspend fun navigateToRTScreen(
     var cycleCount = 0
     val pathIt = path.iterator()
     var nextPathItem = pathIt.next()
+    var previousScreenType: KClassifier? = null
     while (true) {
         if (cycleCount >= rtNavigationContext.maxNumCycleAttempts)
             throw CouldNotFindRTScreenException(targetScreenType)
@@ -993,6 +994,16 @@ suspend fun navigateToRTScreen(
         val parsedDisplayFrame = rtNavigationContext.getParsedDisplayFrame(filterDuplicates = true) ?: continue
         val parsedScreen = parsedDisplayFrame.parsedScreen
 
+        // Check if we got the same screen with different content, for example
+        // when remaining TBR duration is shown on the main screen and the
+        // duration happens to change during this loop. If this occurs,
+        // skip the redundant screen.
+        if ((previousScreenType != null) && (previousScreenType == parsedScreen::class)) {
+            logger(LogLevel.DEBUG) { "Got a screen of the same type ${parsedScreen::class}; skipping" }
+            continue
+        }
+        previousScreenType = parsedScreen::class
+
         // A path item's targetNodeValue is the screen type we are trying
         // to reach, and the edgeValue is the RT button to press to reach it.
         // We stay at the same path item until we reach the screen type that

pump/combov2/comboctl/src/jvmTest/kotlin/info/nightscout/comboctl/main/RTNavigationTest.kt

@@ -597,6 +597,50 @@ class RTNavigationTest {
         assertContentEquals(expectedShortRTButtonPressSequence, rtNavigationContext.shortPressedRTButtons)
     }
 
+    @Test
+    fun checkRTNavigationFromMainToQuickinfoWithChangingRemainingTbrDuration() {
+        // Check that RT screen navigation skips a newly received screen
+        // if it is of the same type as the previously observed screen.
+        // This typically happens because a quantity like the remaining
+        // TBR duration changes on screen. The navigation code has to
+        // check that the _type_ of the screen changed, and if not, it
+        // must skip the screen. Here, we simulate a main TBR screen
+        // whose remaining TBR duration changes. We expect the navigation
+        // code to detect this and press CHECK just _once_ (because the
+        // second TBR main screen is skipped by the detection). Without
+        // the screen type check, it would press CHECK _twice_.
+
+        val rtNavigationContext = TestRTNavigationContext(listOf(
+            ParsedScreen.MainScreen(MainScreenContent.Tbr(
+                currentTime = LocalDateTime(year = 2020, monthNumber = 10, dayOfMonth = 4, hour = 0, minute = 0),
+                remainingTbrDurationInMinutes = 28,
+                tbrPercentage = 110,
+                activeBasalProfileNumber = 1,
+                currentBasalRateFactor = 300,
+                batteryState = BatteryState.FULL_BATTERY
+            )),
+            ParsedScreen.MainScreen(MainScreenContent.Tbr(
+                currentTime = LocalDateTime(year = 2020, monthNumber = 10, dayOfMonth = 4, hour = 0, minute = 0),
+                remainingTbrDurationInMinutes = 27,
+                tbrPercentage = 110,
+                activeBasalProfileNumber = 1,
+                currentBasalRateFactor = 300,
+                batteryState = BatteryState.FULL_BATTERY
+            )),
+            ParsedScreen.QuickinfoMainScreen(Quickinfo(availableUnits = 105, reservoirState = ReservoirState.FULL))
+        ))
+
+        runBlockingWithWatchdog(6000) {
+            navigateToRTScreen(rtNavigationContext, ParsedScreen.QuickinfoMainScreen::class, isComboStopped = false)
+        }
+
+        val expectedShortRTButtonPressSequence = listOf(
+            RTNavigationButton.CHECK
+        )
+
+        assertContentEquals(expectedShortRTButtonPressSequence, rtNavigationContext.shortPressedRTButtons)
+    }
+
     @Test
     fun checkLongPressRTButtonUntil() {
         // Test long RT button presses by simulating transitions