Reinstate landing chat animation

app/src/main/java/org/thoughtcrime/securesms/onboarding/LandingActivity.kt

@@ -3,18 +3,33 @@ package org.thoughtcrime.securesms.onboarding
 import android.content.Intent
 import android.net.Uri
 import android.os.Bundle
+import androidx.annotation.StringRes
+import androidx.compose.animation.AnimatedVisibility
+import androidx.compose.animation.core.tween
+import androidx.compose.animation.fadeIn
+import androidx.compose.animation.slideInVertically
+import androidx.compose.foundation.ExperimentalFoundationApi
 import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
-import androidx.compose.foundation.layout.ColumnScope
 import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.lazy.rememberLazyListState
 import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material.MaterialTheme
 import androidx.compose.material.Text
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
@@ -25,6 +40,7 @@ import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.tooling.preview.PreviewParameter
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
+import kotlinx.coroutines.delay
 import network.loki.messenger.R
 import org.session.libsession.utilities.TextSecurePreferences
 import org.thoughtcrime.securesms.BaseActionBarActivity
@@ -40,9 +56,21 @@ import org.thoughtcrime.securesms.ui.OutlineButton
 import org.thoughtcrime.securesms.ui.PreviewTheme
 import org.thoughtcrime.securesms.ui.ThemeResPreviewParameterProvider
 import org.thoughtcrime.securesms.ui.classicDarkColors
-import org.thoughtcrime.securesms.ui.contentDescription
 import org.thoughtcrime.securesms.ui.session_accent
 import org.thoughtcrime.securesms.util.setUpActionBarSessionLogo
+import kotlin.time.Duration.Companion.milliseconds
+
+private data class TextData(
+    @StringRes val stringId: Int,
+    val isOutgoing: Boolean = false
+)
+
+private val MESSAGES = listOf(
+    TextData(R.string.onboardingBubbleWelcomeToSession),
+    TextData(R.string.onboardingBubbleSessionIsEngineered, isOutgoing = true),
+    TextData(R.string.onboardingBubbleNoPhoneNumber),
+    TextData(R.string.onboardingBubbleCreatingAnAccountIsEasy, isOutgoing = true)
+)
 
 class LandingActivity : BaseActionBarActivity() {
 
@@ -75,19 +103,51 @@ class LandingActivity : BaseActionBarActivity() {
         }
     }
 
+    @OptIn(ExperimentalFoundationApi::class)
     @Composable
     private fun LandingScreen() {
+
+        var count by remember { mutableStateOf(0) }
+        val listState = rememberLazyListState()
+
+        LaunchedEffect(Unit) {
+            delay(500.milliseconds)
+            while(count < MESSAGES.size) {
+                count += 1
+                listState.animateScrollToItem(0.coerceAtLeast((count - 1)))
+                delay(1500L)
+            }
+        }
+
         Column(modifier = Modifier.padding(horizontal = 36.dp)) {
             Spacer(modifier = Modifier.weight(1f))
-            Text(stringResource(R.string.onboardingBubblePrivacyInYourPocket), modifier = Modifier.align(Alignment.CenterHorizontally), style = MaterialTheme.typography.h4, textAlign = TextAlign.Center)
+            Text(
+                stringResource(R.string.onboardingBubblePrivacyInYourPocket),
+                modifier = Modifier.align(Alignment.CenterHorizontally),
+                style = MaterialTheme.typography.h4,
+                textAlign = TextAlign.Center
+            )
             Spacer(modifier = Modifier.height(24.dp))
-            IncomingText(stringResource(R.string.onboardingBubbleWelcomeToSession))
-            Spacer(modifier = Modifier.height(14.dp))
-            OutgoingText(stringResource(R.string.onboardingBubbleSessionIsEngineered))
-            Spacer(modifier = Modifier.height(14.dp))
-            IncomingText(stringResource(R.string.onboardingBubbleNoPhoneNumber))
-            Spacer(modifier = Modifier.height(14.dp))
-            OutgoingText(stringResource(R.string.onboardingBubbleCreatingAnAccountIsEasy))
+
+            LazyColumn(
+                state = listState,
+                modifier = Modifier
+                    .fillMaxWidth()
+                    .weight(1f),
+                verticalArrangement = Arrangement.spacedBy(16.dp)
+            ) {
+                items(
+                    MESSAGES.take(count),
+                    key = { it.stringId }
+                ) { item ->
+                    MessageText(
+                        stringResource(item.stringId),
+                        item.isOutgoing,
+                        modifier = Modifier.animateItemPlacement()
+                    )
+                }
+            }
+
             Spacer(modifier = Modifier.weight(1f))
 
             OutlineButton(
@@ -139,23 +199,31 @@ class LandingActivity : BaseActionBarActivity() {
     }
 
     @Composable
-    private fun IncomingText(text: String) {
-        ChatText(
-            text,
-            color = classicDarkColors[2]
-        )
+    private fun MessageText(text: String, isOutgoing: Boolean, modifier: Modifier) {
+        if (isOutgoing) OutgoingText(text, modifier) else IncomingText(text, modifier)
     }
 
     @Composable
-    private fun ColumnScope.OutgoingText(text: String) {
+    private fun IncomingText(text: String, modifier: Modifier) {
         ChatText(
             text,
-            color = session_accent,
-            textColor = MaterialTheme.colors.primary,
-            modifier = Modifier.align(Alignment.End)
+            color = classicDarkColors[2],
+            modifier = modifier
         )
     }
 
+    @Composable
+    private fun OutgoingText(text: String, modifier: Modifier) {
+        Box(modifier = modifier then Modifier.fillMaxWidth()) {
+            ChatText(
+                text,
+                color = session_accent,
+                textColor = MaterialTheme.colors.primary,
+                modifier = Modifier.align(Alignment.TopEnd)
+            )
+        }
+    }
+
     @Composable
     private fun ChatText(
         text: String,