From 2e503422c8a1cb45a5d024fc6eb6381112c764db Mon Sep 17 00:00:00 2001
From: Harsh Shandilya <me@msfjarvis.dev>
Date: Mon, 7 Feb 2022 14:53:08 +0530
Subject: [PATCH] android: fix navigation backstack handling

As seen previously in #66
---
 .../kotlin/dev/msfjarvis/claw/android/ui/LobstersApp.kt    | 2 +-
 .../claw/android/ui/decorations/ClawNavigationBar.kt       | 7 ++++++-
 .../msfjarvis/claw/android/ui/navigation/Destinations.kt   | 5 +++++
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/android/src/main/kotlin/dev/msfjarvis/claw/android/ui/LobstersApp.kt b/android/src/main/kotlin/dev/msfjarvis/claw/android/ui/LobstersApp.kt
index e497afca..d3c4693e 100644
--- a/android/src/main/kotlin/dev/msfjarvis/claw/android/ui/LobstersApp.kt
+++ b/android/src/main/kotlin/dev/msfjarvis/claw/android/ui/LobstersApp.kt
@@ -122,7 +122,7 @@ fun LobstersApp(
       ) {
         NavHost(
           navController,
-          startDestination = Destinations.Hottest.getRoute(),
+          startDestination = Destinations.startDestination.getRoute(),
           modifier = Modifier.padding(top = 8.dp),
         ) {
           composable(Destinations.Hottest.getRoute()) {
diff --git a/android/src/main/kotlin/dev/msfjarvis/claw/android/ui/decorations/ClawNavigationBar.kt b/android/src/main/kotlin/dev/msfjarvis/claw/android/ui/decorations/ClawNavigationBar.kt
index 14857741..1da832e0 100644
--- a/android/src/main/kotlin/dev/msfjarvis/claw/android/ui/decorations/ClawNavigationBar.kt
+++ b/android/src/main/kotlin/dev/msfjarvis/claw/android/ui/decorations/ClawNavigationBar.kt
@@ -19,6 +19,7 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.painter.Painter
 import androidx.navigation.NavController
 import dev.msfjarvis.claw.android.ui.AnimationDuration
+import dev.msfjarvis.claw.android.ui.navigation.Destinations
 
 @Composable
 fun ClawNavigationBar(
@@ -53,7 +54,11 @@ fun ClawNavigationBar(
           selected = selectedIndex == index,
           onClick = {
             selectedIndex = index
-            navController.navigate(navItem.route)
+            if (navController.currentDestination?.route == navItem.route) return@NavigationBarItem
+            navController.popBackStack(navController.graph.startDestinationRoute!!, false)
+            if (navItem.route != Destinations.startDestination.getRoute()) {
+              navController.navigate(navItem.route)
+            }
           }
         )
       }
diff --git a/android/src/main/kotlin/dev/msfjarvis/claw/android/ui/navigation/Destinations.kt b/android/src/main/kotlin/dev/msfjarvis/claw/android/ui/navigation/Destinations.kt
index d422a429..e1f6b309 100644
--- a/android/src/main/kotlin/dev/msfjarvis/claw/android/ui/navigation/Destinations.kt
+++ b/android/src/main/kotlin/dev/msfjarvis/claw/android/ui/navigation/Destinations.kt
@@ -12,4 +12,9 @@ sealed class Destinations(internal val route: String) {
   object Comments : Destinations("comments/%s") {
     fun getRoute(postId: String) = route.format(postId)
   }
+
+  companion object {
+    val startDestination
+      get() = Hottest
+  }
 }