From 6d5f9760c3d210ebce52b4dfc3d7f4be5efdfb93 Mon Sep 17 00:00:00 2001
From: junkwarrior87 <115852752+junkwarrior87@users.noreply.github.com>
Date: Wed, 12 Mar 2025 17:41:34 +0800
Subject: [PATCH] fix(stage-web): fix textarea behaviors (#72)

---
 .../components/Layouts/InteractiveArea.vue    |  2 +-
 .../stage-ui/src/components/BasicTextarea.vue | 64 +++++--------------
 2 files changed, 16 insertions(+), 50 deletions(-)

diff --git a/apps/stage-web/src/components/Layouts/InteractiveArea.vue b/apps/stage-web/src/components/Layouts/InteractiveArea.vue
index eb851dc85..3349c01a0 100644
--- a/apps/stage-web/src/components/Layouts/InteractiveArea.vue
+++ b/apps/stage-web/src/components/Layouts/InteractiveArea.vue
@@ -198,7 +198,7 @@ onAfterSend(async () => {
             :placeholder="t('stage.message')"
             text="primary-300 hover:primary-500 dark:primary-300/50 dark:hover:primary-500 placeholder:primary-300 placeholder:hover:primary-500 placeholder:dark:primary-300/50 placeholder:dark:hover:primary-500"
             bg="primary-100 dark:primary-400/20"
-            min-h="[100px]" w-full
+            min-h="[100px]" max-h="[300px]" w-full
             rounded-t-xl p-4 font-medium
             outline-none transition="all duration-250 ease-in-out placeholder:all placeholder:duration-250 placeholder:ease-in-out"
             @submit="handleSend"
diff --git a/packages/stage-ui/src/components/BasicTextarea.vue b/packages/stage-ui/src/components/BasicTextarea.vue
index b5b1d68cd..d74983d0a 100644
--- a/packages/stage-ui/src/components/BasicTextarea.vue
+++ b/packages/stage-ui/src/components/BasicTextarea.vue
@@ -1,7 +1,5 @@
-<script setup lang="ts" generic="T extends any, O extends any">
-import type { CSSProperties } from 'vue'
-
-import { nextTick, onMounted, ref } from 'vue'
+<script setup lang="ts">
+import { ref, watch } from 'vue'
 
 const events = defineEmits<{
   (event: 'submit', message: string): void
@@ -12,65 +10,33 @@ const input = defineModel<string>({
 })
 
 const textareaRef = ref<HTMLTextAreaElement>()
-const textareaStyle = ref<CSSProperties>({
-  height: 'auto',
-  overflowY: 'hidden',
-})
+const textareaHeight = ref('auto')
 
-// javascript - Creating a textarea with auto-resize - Stack Overflow
-// https://stackoverflow.com/questions/454202/creating-a-textarea-with-auto-resize
-function onInput(e: Event) {
-  if (!(e.target instanceof HTMLTextAreaElement))
-    return
-
-  e.target.style.height = 'auto'
-  e.target.style.height = `${e.target.scrollHeight}px`
-}
-
-// javascript - How do I detect "shift+enter" and generate a new line in Textarea? - Stack Overflow
-// https://stackoverflow.com/questions/6014702/how-do-i-detect-shiftenter-and-generate-a-new-line-in-textarea
 function onKeyDown(e: KeyboardEvent) {
-  if (!(e.target instanceof HTMLTextAreaElement))
-    return
-
-  if (e.code === 'Enter' && e.shiftKey) {
-    e.preventDefault()
-    const start = e.target?.selectionStart
-    const end = e.target?.selectionEnd
-    input.value = `${input.value.substring(0, start)}\n${input.value.substring(end)}`
-
-    // javascript - height of textarea increases when value increased but does not reduce when value is decreased - Stack Overflow
-    // https://stackoverflow.com/questions/10722058/height-of-textarea-increases-when-value-increased-but-does-not-reduce-when-value
-    textareaStyle.value.height = '0'
-
-    nextTick().then(() => {
-      if (!textareaRef.value)
-        return
-
-      textareaRef.value.selectionStart = textareaRef.value.selectionEnd = start + 1
-      textareaStyle.value.height = `${textareaRef.value.scrollHeight}px`
-    })
-  }
-  else if (e.code === 'Enter') { // block enter
+  if (e.code === 'Enter' && !e.shiftKey) { // just block Enter is enough, Shift+Enter by default generates a newline
     e.preventDefault()
     events('submit', input.value)
   }
 }
 
-onMounted(() => {
-  if (!textareaRef.value)
-    return
+// javascript - Creating a textarea with auto-resize - Stack Overflow
+// https://stackoverflow.com/questions/454202/creating-a-textarea-with-auto-resize
+watch(input, () => {
+  textareaHeight.value = 'auto'
+  requestAnimationFrame(() => {
+    if (!textareaRef.value)
+      return
 
-  textareaStyle.value.height = `${textareaRef.value.scrollHeight}px`
-})
+    textareaHeight.value = `${textareaRef.value.scrollHeight}px`
+  })
+}, { immediate: true })
 </script>
 
 <template>
   <textarea
     ref="textareaRef"
     v-model="input"
-    :style="textareaStyle"
-    @input="onInput"
+    :style="{ height: textareaHeight }"
     @keydown="onKeyDown"
   />
 </template>