fix(ui/chat): improve ChatInput resizability; improve send button animation

ui/components/src/main/kotlin/com/getcode/ui/components/chat/ChatInput.kt

@@ -1,32 +1,23 @@
 package com.getcode.ui.components.chat
 
-import androidx.compose.animation.AnimatedContent
+import androidx.compose.animation.animateContentSize
+import androidx.compose.animation.core.animateFloatAsState
 import androidx.compose.animation.core.spring
-import androidx.compose.animation.fadeIn
-import androidx.compose.animation.fadeOut
-import androidx.compose.animation.scaleIn
-import androidx.compose.animation.scaleOut
-import androidx.compose.animation.togetherWith
 import androidx.compose.foundation.background
 import androidx.compose.foundation.clickable
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
-import androidx.compose.foundation.layout.IntrinsicSize
 import androidx.compose.foundation.layout.PaddingValues
 import androidx.compose.foundation.layout.Row
-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.requiredSize
 import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.text.KeyboardOptions
 import androidx.compose.foundation.text.input.TextFieldState
 import androidx.compose.foundation.text.input.rememberTextFieldState
 import androidx.compose.material3.Icon
-import androidx.compose.material.icons.Icons
-import androidx.compose.material.icons.rounded.ArrowUpward
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
 import androidx.compose.runtime.remember
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
@@ -57,13 +48,25 @@ fun ChatInput(
     onSendMessage: () -> Unit,
 ) {
     val shape = CodeTheme.shapes.medium
+    val sendVisible = state.text.isNotEmpty()
+    val sendSpec = spring<Float>(dampingRatio = 0.66f, stiffness = 4000f)
+    val sendAlpha by animateFloatAsState(
+        targetValue = if (sendVisible) 1f else 0f,
+        animationSpec = sendSpec,
+        label = "send button alpha",
+    )
+    val sendScale by animateFloatAsState(
+        targetValue = if (sendVisible) 1f else 0.6f,
+        animationSpec = sendSpec,
+        label = "send button scale",
+    )
     Row(
         modifier = Modifier
             .graphicsLayer { compositingStrategy = CompositingStrategy.Offscreen }
             .clip(shape)
             .then(modifier)
             .fillMaxWidth()
-            .height(IntrinsicSize.Min),
+            .animateContentSize(),
         horizontalArrangement = Arrangement.spacedBy(CodeTheme.dimens.grid.x2),
         verticalAlignment = Alignment.Bottom
     ) {
@@ -93,36 +96,27 @@ fun ChatInput(
                 unfocusedBorderColor = Color.Transparent,
             ),
             trailingIcon = {
-                AnimatedContent(
-                    targetState = state.text.isNotEmpty(),
-                    label = "show/hide send button",
-                    transitionSpec = {
-                        val spec = spring<Float>(dampingRatio = 0.66f, stiffness = 4000f)
-                        (fadeIn(spec) + scaleIn(spec, initialScale = 0.6f)) togetherWith
-                                (fadeOut(spec) + scaleOut(spec, targetScale = 0.6f))
-                    }
-                ) { show ->
-                    if (show) {
-                        Icon(
-                            modifier = Modifier
-                                .padding(vertical = CodeTheme.dimens.grid.x1)
-                                .padding(end = CodeTheme.dimens.staticGrid.x1)
-                                .background(
-                                    Color.White,
-                                    shape = CodeTheme.shapes.extraSmall
-                                )
-                                .clip(CodeTheme.shapes.extraSmall)
-                                .clickable { onSendMessage() }
-                                .padding(CodeTheme.dimens.staticGrid.x1)
-                                .size(CodeTheme.dimens.staticGrid.x5),
-                            painter = painterResource(R.drawable.ic_arrow_up),
-                            tint = Color.Black,
-                            contentDescription = "Send message"
+                Icon(
+                    modifier = Modifier
+                        .graphicsLayer {
+                            alpha = sendAlpha
+                            scaleX = sendScale
+                            scaleY = sendScale
+                        }
+                        .padding(vertical = CodeTheme.dimens.grid.x1)
+                        .padding(end = CodeTheme.dimens.staticGrid.x1)
+                        .background(
+                            Color.White,
+                            shape = CodeTheme.shapes.extraSmall
                         )
-                    } else {
-                        Spacer(Modifier.requiredSize(CodeTheme.dimens.staticGrid.x9))
-                    }
-                }
+                        .clip(CodeTheme.shapes.extraSmall)
+                        .clickable(enabled = sendVisible) { onSendMessage() }
+                        .padding(CodeTheme.dimens.staticGrid.x1)
+                        .size(CodeTheme.dimens.staticGrid.x5),
+                    painter = painterResource(R.drawable.ic_arrow_up),
+                    tint = Color.Black,
+                    contentDescription = "Send message"
+                )
             }
         )
     }