feat: PC용 툴바 마크다운 에디터 (한글 IME 정상)

- Toast UI 는 Windows IME 와 충돌(업스트림 버그)하므로 PC(Electron)에선 textarea 기반
  마크다운 에디터 사용: 툴바(제목·굵게·기울임·취소선·인용·목록·체크·링크·코드·구분선) + Write/Preview 탭
- textarea(v-model)라 한글 IME 정상. 웹/APK 는 Toast UI 위지윅 유지

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/components/editor/MarkdownEditor.vue

@@ -1,10 +1,11 @@
 <script setup>
-import { ref, onMounted, onBeforeUnmount, watch } from 'vue'
+import { ref, onMounted, onBeforeUnmount, watch, nextTick } from 'vue'
 import Editor from '@toast-ui/editor'
 import '@toast-ui/editor/dist/toastui-editor.css'
 import codeSyntaxHighlight from '@toast-ui/editor-plugin-code-syntax-highlight/dist/toastui-editor-plugin-code-syntax-highlight-all'
 import 'prismjs/themes/prism-tomorrow.css'
 import '@toast-ui/editor-plugin-code-syntax-highlight/dist/toastui-editor-plugin-code-syntax-highlight.css'
+import MarkdownViewer from '@/components/editor/MarkdownViewer.vue'
 
 const props = defineProps({
   modelValue: { type: String, default: '' },
@@ -14,13 +15,16 @@ const props = defineProps({
 })
 const emit = defineEmits(['update:modelValue'])
 
-// PC(Electron)는 Toast UI 에디터(위지윅·CodeMirror 모두)에서 한글 IME 첫 자음이 중복되는
+// PC(Electron)는 Toast UI 에디터(위지윅·CodeMirror)가 Windows IME 와 충돌해 한글 첫 자음이 중복된다
-// Chromium 버그가 있다(제목 등 일반 입력은 정상). → PC 에선 일반 textarea(네이티브 IME)로 입력받는다.
+// (tui.editor 업스트림 버그, 일반 input/textarea 는 정상). → PC 에선 textarea 기반 마크다운 에디터를 쓴다.
 // 웹/모바일(APK)은 기존 Toast UI 위지윅 유지.
 const isElectron = typeof navigator !== 'undefined' && /electron/i.test(navigator.userAgent)
 
-// ===== PC: 일반 textarea (Vue v-model 이 IME 조합을 올바르게 처리) =====
+/* ===================== PC: textarea 기반 마크다운 에디터 ===================== */
 const text = ref(props.modelValue || '')
+const taRef = ref(null)
+const mode = ref('write') // 'write' | 'preview'
+
 if (isElectron) {
   watch(text, (v) => emit('update:modelValue', v))
   watch(
@@ -31,7 +35,75 @@ if (isElectron) {
   )
 }
 
-// ===== 웹/APK: Toast UI 위지윅 =====
+// 선택 영역을 마커로 감싸기(굵게/기울임/코드 등)
+function surround(before, after = before, placeholder = '') {
+  const ta = taRef.value
+  if (!ta) return
+  const s = ta.selectionStart
+  const e = ta.selectionEnd
+  const val = text.value
+  const sel = val.slice(s, e) || placeholder
+  text.value = val.slice(0, s) + before + sel + after + val.slice(e)
+  nextTick(() => {
+    ta.focus()
+    const start = s + before.length
+    ta.setSelectionRange(start, start + sel.length)
+  })
+}
+
+// 선택한 줄들 앞에 접두어 추가(제목/인용/목록 등)
+function linePrefix(prefix) {
+  const ta = taRef.value
+  if (!ta) return
+  const s = ta.selectionStart
+  const e = ta.selectionEnd
+  const val = text.value
+  const lineStart = val.lastIndexOf('\n', s - 1) + 1
+  const block = val.slice(lineStart, e)
+  const prefixed = block
+    .split('\n')
+    .map((ln) => prefix + ln)
+    .join('\n')
+  text.value = val.slice(0, lineStart) + prefixed + val.slice(e)
+  nextTick(() => {
+    ta.focus()
+    ta.setSelectionRange(lineStart, lineStart + prefixed.length)
+  })
+}
+
+// 현재 위치에 블록 삽입(코드블록/구분선)
+function insertBlock(block) {
+  const ta = taRef.value
+  if (!ta) return
+  const s = ta.selectionStart
+  const val = text.value
+  const nl = s > 0 && val[s - 1] !== '\n' ? '\n' : ''
+  const insert = nl + block + '\n'
+  text.value = val.slice(0, s) + insert + val.slice(s)
+  nextTick(() => {
+    ta.focus()
+    const pos = s + insert.length
+    ta.setSelectionRange(pos, pos)
+  })
+}
+
+function insertLink() {
+  const ta = taRef.value
+  if (!ta) return
+  const s = ta.selectionStart
+  const e = ta.selectionEnd
+  const val = text.value
+  const sel = val.slice(s, e) || '링크텍스트'
+  const md = `[${sel}](url)`
+  text.value = val.slice(0, s) + md + val.slice(e)
+  nextTick(() => {
+    ta.focus()
+    const urlStart = s + sel.length + 3 // "[sel]("
+    ta.setSelectionRange(urlStart, urlStart + 3)
+  })
+}
+
+/* ===================== 웹/APK: Toast UI 위지윅 ===================== */
 const el = ref(null)
 let editor = null
 let lastEmitted = props.modelValue || ''
@@ -77,34 +149,136 @@ onBeforeUnmount(() => {
 </script>
 
 <template>
-  <!-- PC(Electron): 일반 textarea — 한글 IME 정상 -->
+  <!-- PC(Electron): textarea 기반 마크다운 에디터 (툴바 + 미리보기) — 한글 IME 정상 -->
+  <div v-if="isElectron" class="mde">
+    <div class="mde-tabs">
+      <button type="button" :class="{ active: mode === 'write' }" @click="mode = 'write'">Write</button>
+      <button type="button" :class="{ active: mode === 'preview' }" @click="mode = 'preview'">Preview</button>
+    </div>
+
+    <div v-show="mode === 'write'">
+      <div class="mde-toolbar">
+        <button type="button" title="제목" @click="linePrefix('## ')"><span class="t-h">H</span></button>
+        <button type="button" title="굵게" @click="surround('**', '**', '굵게')"><b>B</b></button>
+        <button type="button" title="기울임" @click="surround('*', '*', '기울임')"><i>I</i></button>
+        <button type="button" title="취소선" @click="surround('~~', '~~', '취소선')"><s>S</s></button>
+        <span class="mde-div"></span>
+        <button type="button" title="인용" @click="linePrefix('&gt; ')">❝</button>
+        <button type="button" title="목록" @click="linePrefix('- ')">•</button>
+        <button type="button" title="번호 목록" @click="linePrefix('1. ')">1.</button>
+        <button type="button" title="체크리스트" @click="linePrefix('- [ ] ')">☑</button>
+        <span class="mde-div"></span>
+        <button type="button" title="링크" @click="insertLink()">🔗</button>
+        <button type="button" title="인라인 코드" @click="surround('`', '`', '코드')">&lt;/&gt;</button>
+        <button type="button" title="코드 블록" @click="insertBlock('```\n코드\n```')">{ }</button>
+        <button type="button" title="구분선" @click="insertBlock('---')">―</button>
+      </div>
       <textarea
-    v-if="isElectron"
+        ref="taRef"
         v-model="text"
-    class="md-textarea"
+        class="mde-textarea"
         :placeholder="placeholder"
         :style="{ height }"
       ></textarea>
-  <!-- 웹/APK: Toast UI 에디터 -->
+    </div>
+
+    <div v-show="mode === 'preview'" class="mde-preview" :style="{ minHeight: height }">
+      <MarkdownViewer v-if="text.trim()" :content="text" />
+      <p v-else class="mde-empty">미리볼 내용이 없습니다.</p>
+    </div>
+  </div>
+
+  <!-- 웹/APK: Toast UI 위지윅 -->
   <div v-else ref="el"></div>
 </template>
 
 <style scoped>
-.md-textarea {
+.mde {
+  border: 1px solid var(--color-border);
+  border-radius: 6px;
+  overflow: hidden;
+  background: var(--color-background-soft);
+}
+.mde-tabs {
+  display: flex;
+  gap: 0.25rem;
+  padding: 0.35rem 0.5rem 0;
+  border-bottom: 1px solid var(--color-border);
+}
+.mde-tabs button {
+  padding: 0.35rem 0.9rem;
+  border: 1px solid transparent;
+  border-bottom: 0;
+  border-radius: 6px 6px 0 0;
+  background: transparent;
+  color: var(--color-text);
+  font-size: 0.85rem;
+  cursor: pointer;
+  opacity: 0.6;
+}
+.mde-tabs button.active {
+  background: var(--color-background);
+  border-color: var(--color-border);
+  opacity: 1;
+  font-weight: 600;
+}
+.mde-toolbar {
+  display: flex;
+  flex-wrap: wrap;
+  align-items: center;
+  gap: 0.15rem;
+  padding: 0.4rem 0.5rem;
+  border-bottom: 1px solid var(--color-border);
+  background: var(--color-background);
+}
+.mde-toolbar button {
+  min-width: 1.9rem;
+  height: 1.9rem;
+  padding: 0 0.4rem;
+  border: 0;
+  border-radius: 4px;
+  background: transparent;
+  color: var(--color-text);
+  font-size: 0.9rem;
+  cursor: pointer;
+  line-height: 1;
+}
+.mde-toolbar button:hover {
+  background: var(--color-background-mute);
+}
+.mde-toolbar .t-h {
+  font-weight: 800;
+}
+.mde-div {
+  width: 1px;
+  height: 1.1rem;
+  margin: 0 0.25rem;
+  background: var(--color-border);
+}
+.mde-textarea {
+  display: block;
   width: 100%;
   box-sizing: border-box;
-  padding: 0.75rem 0.9rem;
+  padding: 0.8rem 0.9rem;
-  border: 1px solid var(--color-border);
+  border: 0;
-  border-radius: 4px;
+  background: var(--color-background);
-  background: var(--color-background-soft);
   color: var(--color-text);
   font-family: inherit;
   font-size: 0.95rem;
-  line-height: 1.6;
+  line-height: 1.7;
   resize: vertical;
 }
-.md-textarea:focus {
+.mde-textarea:focus {
   outline: none;
-  border-color: hsla(160, 100%, 37%, 1);
+}
+.mde-preview {
+  padding: 0.8rem 0.9rem;
+  background: var(--color-background);
+  overflow: auto;
+}
+.mde-empty {
+  opacity: 0.5;
+  font-size: 0.9rem;
+  margin: 0;
 }
 </style>