Revert "app: remove now uneeded navigation code"

This reverts commit 41c64f4b02.

app/src/androidTest/java/dev/msfjarvis/lobsters/BottomNavigationLayoutTest.kt

@@ -0,0 +1,115 @@
+package dev.msfjarvis.lobsters
+
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.test.assertContentDescriptionEquals
+import androidx.compose.ui.test.assertCountEquals
+import androidx.compose.ui.test.assertHasClickAction
+import androidx.compose.ui.test.assertIsDisplayed
+import androidx.compose.ui.test.assertIsNotSelected
+import androidx.compose.ui.test.assertIsSelected
+import androidx.compose.ui.test.assertTextEquals
+import androidx.compose.ui.test.junit4.createComposeRule
+import androidx.compose.ui.test.onChildAt
+import androidx.compose.ui.test.onChildren
+import androidx.compose.ui.test.onNodeWithTag
+import androidx.compose.ui.test.performClick
+import dev.msfjarvis.lobsters.ui.main.LobstersBottomNav
+import dev.msfjarvis.lobsters.ui.navigation.Destination
+import dev.msfjarvis.lobsters.ui.theme.LobstersTheme
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
+
+
+class BottomNavigationLayoutTest {
+
+  @get:Rule
+  val composeTestRule = createComposeRule()
+
+  @Before
+  fun setUp() {
+    composeTestRule.setContent {
+      LobstersTheme {
+        var mutableDestination by remember { mutableStateOf(Destination.startDestination) }
+
+        LobstersBottomNav(
+          currentDestination = mutableDestination,
+          navigateToDestination = { mutableDestination = it },
+          jumpToIndex = {}
+        )
+      }
+    }
+  }
+
+  @Test
+  fun bottomNavItemCountTest() {
+    // Test to make sure total items are equal to enum objects present in Destination
+    composeTestRule.onNodeWithTag("LobstersBottomNav")
+      .assertExists()
+      .assertIsDisplayed()
+      .onChildren()
+      .assertCountEquals(Destination.values().size)
+  }
+
+  @Test
+  fun bottomNavItemTest() {
+    // Check hottest BottomNavItem is rendered correctly
+    composeTestRule.onNodeWithTag("LobstersBottomNav")
+      .assertExists()
+      .assertIsDisplayed()
+      .onChildAt(0)
+      .assertTextEquals("Hottest")
+      .assertContentDescriptionEquals("Hottest")
+      .assertHasClickAction()
+
+    // Check saved BottomNavItem is rendered correctly
+    composeTestRule.onNodeWithTag("LobstersBottomNav")
+      .assertExists()
+      .assertIsDisplayed()
+      .onChildAt(1)
+      .assertTextEquals("Saved")
+      .assertContentDescriptionEquals("Saved")
+      .assertHasClickAction()
+  }
+
+  @Test
+  fun bottomNavItemSelectedTest() {
+    // Check hottest BottomNav item is selected
+    composeTestRule.onNodeWithTag("LobstersBottomNav")
+      .assertExists()
+      .assertIsDisplayed()
+      .onChildAt(0)
+      .assertIsSelected()
+      .assertTextEquals("Hottest")
+
+    // Check saved BottomNav item is not selected
+    composeTestRule.onNodeWithTag("LobstersBottomNav")
+      .assertExists()
+      .assertIsDisplayed()
+      .onChildAt(1)
+      .assertIsNotSelected()
+
+    // Select the saved BottomNav item
+    composeTestRule.onNodeWithTag("LobstersBottomNav")
+      .onChildAt(1)
+      .performClick()
+
+    // Check hottest BottomNav item is not selected
+    composeTestRule.onNodeWithTag("LobstersBottomNav")
+      .assertExists()
+      .assertIsDisplayed()
+      .onChildAt(0)
+      .assertIsNotSelected()
+
+    // Check saved BottomNav item is selected
+    composeTestRule.onNodeWithTag("LobstersBottomNav")
+      .assertExists()
+      .assertIsDisplayed()
+      .onChildAt(1)
+      .assertIsSelected()
+      .assertTextEquals("Saved")
+  }
+}

app/src/main/java/dev/msfjarvis/lobsters/ui/navigation/Destination.kt

@@ -0,0 +1,26 @@
+package dev.msfjarvis.lobsters.ui.navigation
+
+import androidx.annotation.DrawableRes
+import androidx.annotation.StringRes
+import dev.msfjarvis.lobsters.R
+
+/**
+ * Destinations for navigation within the app.
+ */
+enum class Destination(
+  val route: String,
+  @StringRes val labelRes: Int,
+  @DrawableRes val badgeRes: Int,
+) {
+  Hottest("hottest", R.string.hottest_posts, R.drawable.ic_whatshot_24px),
+  Saved("saved", R.string.saved_posts, R.drawable.ic_favorite_24px),
+  ;
+
+  companion object {
+    val startDestination = Hottest
+
+    fun getDestinationFromRoute(route: String): Destination {
+      return values().firstOrNull { it.route == route } ?: error("Incorrect route passed")
+    }
+  }
+}