Omnibar: Pixel and Clear action regressions (#5304)

Task/Issue URL:
https://app.asana.com/0/1205782002757341/1208820359395089/f

### Description

### Steps to test this PR
Looks at this task for different scenarios:
https://app.asana.com/0/1174433894299346/1208812333027437/f

_Pixel for clearing address bar - Site_
- [x] Navigate to a site
- [x] Tap into address bar
- [x] X to delete entry (don’t type anything new)
- [x] Swipe gesture to close keyboard 
- [x] Verify pixel `m_addressbar_focus_clear_entry_website` is fired
only once

_Pixel for clearing address bar - SERP_
- [x] Navigate to a site
- [x] Tap into address bar
- [x] X to delete entry (don’t type anything new)
- [x] Swipe gesture to close keyboard 
- [x] Verify pixel `m_addressbar_focus_clear_entry_serp ` is fired only
once

_Pixel for clearing address bar - NTP_
- [x] Navigate to a site
- [x] Tap into address bar
- [x] X to delete entry (don’t type anything new)
- [x] Swipe gesture to close keyboard 
- [x] Verify pixel `m_addressbar_focus_clear_entry_ntp ` is fired only
once

_Swipe gesture to close keyboard - Site_
- [x] Navigate to a site
- [x] Tap into address bar
- [x] X to delete entry (don’t type anything new)
- [x] Swipe gesture to close keyboard 
- [x] Verify Site url is displayed

_Swipe gesture to close keyboard - SERP_
- [x] Enter a search query on SERP
- [x] Tap into address bar
- [x] X to delete entry (don’t type anything new)
- [x] Swipe gesture to close keyboard 
- [x] Verify query is displayed

_Manually close keyboard  + Scroll- Site_
- [x] Navigate to a site
- [x] Tap into address bar
- [x] X to delete entry (don’t type anything new)
- [x] Manually close keyboard
- [x] Scroll down the site
- [x] Verify Site url is displayed

_Manually close keyboard  + Scroll- SERP_
- [x] Enter a search query on SERP
- [x] Tap into address bar
- [x] X to delete entry (don’t type anything new)
- [x] Manually close keyboard
- [x] Scroll down the site
- [x] Verify query is displayed

_Close keyboard - Site_
- [x] Ensure 3 button navigation is enabled (via device Settings)
- [x] Navigate to a site
- [x] Tap into address bar
- [x] X to delete entry (don’t type anything new)
- [x] Close keyboard (press back)
- [x] Verify Site url is displayed

_Close keyboard - SERP_
- [x] Ensure 3 button navigation is enabled (via device Settings)
- [x] Enter a search query on SERP
- [x] Tap into address bar
- [x] X to delete entry (don’t type anything new)
- [x] Close keyboard (press back)
- [x] Verify query is displayed

app/src/main/java/com/duckduckgo/app/browser/BrowserTabFragment.kt

@@ -955,8 +955,10 @@ class BrowserTabFragment :
     }
 
     private fun onOmnibarClearTextButtonPressed() {
-        viewModel.onClearOmnibarTextInput()
-        omnibar.setText("")
+        if (!changeOmnibarPositionFeature.refactor().isEnabled()) {
+            viewModel.onClearOmnibarTextInput()
+            omnibar.setText("")
+        }
     }
 
     private fun configureCustomTab() {

app/src/main/java/com/duckduckgo/app/browser/omnibar/OmnibarLayout.kt

@@ -296,11 +296,15 @@ class OmnibarLayout @JvmOverloads constructor(
 
         omnibarTextInput.replaceTextChangedListener(
             object : TextChangedWatcher() {
+                var clearQuery = false
+                var deleteLastCharacter = false
                 override fun afterTextChanged(editable: Editable) {
                     if (isAttachedToWindow) {
                         viewModel.onInputStateChanged(
                             omnibarTextInput.text.toString(),
                             omnibarTextInput.hasFocus(),
+                            clearQuery,
+                            deleteLastCharacter,
                         )
                     }
                     omnibarTextListener?.onOmnibarTextChanged(
@@ -310,6 +314,12 @@ class OmnibarLayout @JvmOverloads constructor(
                         ),
                     )
                 }
+
+                override fun beforeTextChanged(s: CharSequence, start: Int, count: Int, after: Int) {
+                    Timber.d("Omnibar: $count characters beginning at $start are about to be replaced by new text with length $after")
+                    clearQuery = start == 0 && after == 0
+                    deleteLastCharacter = count == 1 && clearQuery
+                }
             },
         )
 
@@ -445,7 +455,6 @@ class OmnibarLayout @JvmOverloads constructor(
     }
 
     private fun renderBrowserMode(viewState: ViewState) {
-        Timber.d("Omnibar: render browserMode $viewState")
         renderOutline(viewState.hasFocus)
         if (viewState.updateOmnibarText) {
             omnibarTextInput.setText(viewState.omnibarText)

app/src/main/java/com/duckduckgo/app/browser/omnibar/OmnibarLayoutViewModel.kt

@@ -23,6 +23,7 @@ import androidx.lifecycle.viewModelScope
 import com.duckduckgo.anvil.annotations.ContributesViewModel
 import com.duckduckgo.app.browser.DuckDuckGoUrlDetector
 import com.duckduckgo.app.browser.omnibar.Omnibar.ViewMode
+import com.duckduckgo.app.browser.omnibar.Omnibar.ViewMode.Browser
 import com.duckduckgo.app.browser.omnibar.Omnibar.ViewMode.CustomTab
 import com.duckduckgo.app.browser.omnibar.Omnibar.ViewMode.Error
 import com.duckduckgo.app.browser.omnibar.Omnibar.ViewMode.NewTab
@@ -90,6 +91,7 @@ class OmnibarLayoutViewModel @Inject constructor(
         val leadingIconState: LeadingIconState = LeadingIconState.SEARCH,
         val privacyShield: PrivacyShield = PrivacyShield.UNKNOWN,
         val hasFocus: Boolean = false,
+        val query: String = "",
         val omnibarText: String = "",
         val url: String = "",
         val expanded: Boolean = false,
@@ -171,6 +173,20 @@ class OmnibarLayoutViewModel @Inject constructor(
             }
         } else {
             _viewState.update {
+                val shouldUpdateOmnibarText = it.viewMode is Browser
+                Timber.d("Omnibar: lost focus in Browser mode $shouldUpdateOmnibarText")
+                val omnibarText = if (shouldUpdateOmnibarText) {
+                    if (duckDuckGoUrlDetector.isDuckDuckGoQueryUrl(it.url)) {
+                        Timber.d("Omnibar: is DDG url, showing query ${it.query}")
+                        it.query
+                    } else {
+                        Timber.d("Omnibar: is url, showing URL ${it.url}")
+                        it.url
+                    }
+                } else {
+                    Timber.d("Omnibar: not browser mode, not changing omnibar text")
+                    it.omnibarText
+                }
                 it.copy(
                     hasFocus = false,
                     expanded = false,
@@ -187,6 +203,8 @@ class OmnibarLayoutViewModel @Inject constructor(
                         urlLoaded = _viewState.value.url,
                     ),
                     shouldMoveCaretToStart = true,
+                    updateOmnibarText = shouldUpdateOmnibarText,
+                    omnibarText = omnibarText,
                 )
             }
         }
@@ -386,13 +404,28 @@ class OmnibarLayoutViewModel @Inject constructor(
     fun onInputStateChanged(
         query: String,
         hasFocus: Boolean,
+        clearQuery: Boolean,
+        deleteLastCharacter: Boolean,
     ) {
-        Timber.d("Omnibar: onInputStateChanged")
         val showClearButton = hasFocus && query.isNotBlank()
         val showControls = !hasFocus || query.isBlank()
 
+        Timber.d("Omnibar: onInputStateChanged query $query hasFocus $hasFocus clearQuery $clearQuery deleteLastCharacter $deleteLastCharacter")
+
         _viewState.update {
+            val updatedQuery = if (deleteLastCharacter) {
+                Timber.d("Omnibar: deleting last character, old query ${it.query} also deleted")
+                it.url
+            } else if (clearQuery) {
+                Timber.d("Omnibar: clearing old query ${it.query}, we keep it as reference")
+                it.query
+            } else {
+                Timber.d("Omnibar: not clearing or deleting old query ${it.query}, updating query to $query")
+                query
+            }
+
             it.copy(
+                query = updatedQuery,
                 omnibarText = query,
                 updateOmnibarText = false,
                 hasFocus = hasFocus,
@@ -501,6 +534,7 @@ class OmnibarLayoutViewModel @Inject constructor(
     }
 
     fun onUserTouchedOmnibarTextInput(touchAction: Int) {
+        Timber.d("Omnibar: onUserTouchedOmnibarTextInput")
         if (touchAction == ACTION_UP) {
             firePixelBasedOnCurrentUrl(
                 AppPixelName.ADDRESS_BAR_NEW_TAB_PAGE_CLICKED,
@@ -517,6 +551,12 @@ class OmnibarLayoutViewModel @Inject constructor(
             AppPixelName.ADDRESS_BAR_SERP_CANCELLED,
             AppPixelName.ADDRESS_BAR_WEBSITE_CANCELLED,
         )
+        _viewState.update {
+            it.copy(
+                omnibarText = it.url,
+                updateOmnibarText = true,
+            )
+        }
     }
 
     fun onEnterKeyPressed() {

app/src/test/java/com/duckduckgo/app/browser/omnibar/OmnibarLayoutViewModelTest.kt

@@ -627,7 +627,9 @@ class OmnibarLayoutViewModelTest {
     fun whenInputStateChangedAndQueryEmptyThenViewStateCorrect() = runTest {
         val query = ""
         val hasFocus = true
-        testee.onInputStateChanged(query, hasFocus)
+        val clearQuery = true
+        val deleteLastCharacter = false
+        testee.onInputStateChanged(query, hasFocus, clearQuery, deleteLastCharacter)
 
         testee.viewState.test {
             val viewState = awaitItem()
@@ -645,7 +647,9 @@ class OmnibarLayoutViewModelTest {
     fun whenInputStateChangedAndQueryNotEmptyThenViewStateCorrect() = runTest {
         val query = "query"
         val hasFocus = true
-        testee.onInputStateChanged(query, hasFocus)
+        val clearQuery = true
+        val deleteLastCharacter = false
+        testee.onInputStateChanged(query, hasFocus, clearQuery, deleteLastCharacter)
 
         testee.viewState.test {
             val viewState = awaitItem()
@@ -815,6 +819,92 @@ class OmnibarLayoutViewModelTest {
         }
     }
 
+    @Test
+    fun whenOmnibarTextClearedAndBackPressedThenUrlIsShown() = runTest {
+        givenSiteLoaded(RANDOM_URL)
+        testee.onClearTextButtonPressed()
+        testee.onBackKeyPressed()
+
+        testee.viewState.test {
+            val viewState = awaitItem()
+            assertTrue(viewState.omnibarText == RANDOM_URL)
+        }
+    }
+
+    @Test
+    fun whenHidingKeyboardAfterClearingInputWhileInSiteThenURLisShown() = runTest {
+        givenSiteLoaded(RANDOM_URL)
+        testee.onClearTextButtonPressed()
+        val hasFocus = true
+        val clearQuery = true
+        val deleteLastCharacter = false
+        testee.onInputStateChanged("", hasFocus, clearQuery, deleteLastCharacter)
+        testee.onOmnibarFocusChanged(false, "")
+        testee.onInputStateChanged(RANDOM_URL, false, false, false)
+
+        testee.viewState.test {
+            val viewState = awaitItem()
+            assertTrue(viewState.omnibarText == RANDOM_URL)
+        }
+    }
+
+    @Test
+    fun whenHidingKeyboardAfterClearingInputWhileInSERPThenURLisShown() = runTest {
+        givenSiteLoaded(SERP_URL)
+
+        val hasFocus = true
+        val clearQuery = true
+        val deleteLastCharacter = false
+
+        testee.onClearTextButtonPressed()
+        testee.onInputStateChanged("", hasFocus, clearQuery, deleteLastCharacter)
+        testee.onOmnibarFocusChanged(false, "")
+        testee.onInputStateChanged(SERP_URL, false, false, false)
+
+        testee.viewState.test {
+            val viewState = awaitItem()
+            assertTrue(viewState.omnibarText == SERP_URL)
+        }
+    }
+
+    @Test
+    fun whenClosingKeyboardAfterDeletingLastCharacterFromOmnibaWhileInSERPThenURLisShown() = runTest {
+        givenSiteLoaded(SERP_URL)
+
+        val hasFocus = true
+        val clearQuery = true
+        val deleteLastCharacter = true
+
+        testee.onClearTextButtonPressed()
+        testee.onInputStateChanged("", hasFocus, clearQuery, deleteLastCharacter)
+        testee.onOmnibarFocusChanged(false, "")
+        testee.onInputStateChanged(SERP_URL, false, false, deleteLastCharacter)
+
+        testee.viewState.test {
+            val viewState = awaitItem()
+            assertTrue(viewState.omnibarText == SERP_URL)
+        }
+    }
+
+    @Test
+    fun whenClosingKeyboardAfterDeletingLastCharacterFromOmnibaWhileInSitehenURLisShown() = runTest {
+        givenSiteLoaded(RANDOM_URL)
+
+        val hasFocus = true
+        val clearQuery = true
+        val deleteLastCharacter = true
+
+        testee.onClearTextButtonPressed()
+        testee.onInputStateChanged("", hasFocus, clearQuery, deleteLastCharacter)
+        testee.onOmnibarFocusChanged(false, "")
+        testee.onInputStateChanged(RANDOM_URL, false, false, deleteLastCharacter)
+
+        testee.viewState.test {
+            val viewState = awaitItem()
+            assertTrue(viewState.omnibarText == RANDOM_URL)
+        }
+    }
+
     private fun givenSiteLoaded(loadedUrl: String) {
         testee.onViewModeChanged(ViewMode.Browser(loadedUrl))
         testee.onExternalStateChange(