Marked.jsというMarkdowonパーサ(text -> html)を使ったMarkdowonエディタ

admin

4時間前

<!doctype html>
<html lang="ja">
<head>
  <meta charset="utf-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1" />
  <title>Markdown Editor — Vanilla JS</title>
  <!-- 最小依存: marked / DOMPurify / highlight.js（任意） をCDNから読み込み -->
  <script src="https://cdn.jsdelivr.net/npm/marked/marked.min.js"></script>
  <script src="https://cdn.jsdelivr.net/npm/dompurify@3.1.6/dist/purify.min.js"></script>
  <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/highlight.js@11.9.0/styles/github-dark.min.css">
  <script src="https://cdn.jsdelivr.net/npm/highlight.js@11.9.0/lib/highlight.min.js"></script>
  <style>
    /* ざっくりとしたUIスタイル。Tailwind等なしで動作可 */
    :root {
      --bg: #0b0b0c;
      --panel: #111214;
      --text: #e7e7ea;
      --muted: #9aa0a6;
      --border: #2a2c30;
      --accent: #4f46e5;
    }
    * { box-sizing: border-box; }
    html, body { height: 100%; }
    body {
      margin: 0; background: var(--bg); color: var(--text);
      font: 14px/1.6 system-ui, -apple-system, Segoe UI, Roboto, "Noto Sans JP", sans-serif;
    }
    header {
      position: sticky; top: 0; z-index: 10;
      backdrop-filter: blur(6px);
      background: color-mix(in oklab, var(--bg) 80%, transparent);
      border-bottom: 1px solid var(--border);
    }
    .wrap { max-width: 1200px; margin: 0 auto; padding: 12px 16px; }
    .title { font-weight: 700; }
    .toolbar { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
    .btn {
      background: var(--panel); border: 1px solid var(--border); color: var(--text);
      padding: 6px 10px; border-radius: 10px; cursor: pointer;
    }
    .btn:hover { background: #17181b; }
    .btn.secondary { color: var(--muted); }
    .spacer { flex: 1; }

    /* 2カラム: 左エディタ / 右プレビュー（中央ドラッグでサイズ変更） */
    .grid {
      display: grid; grid-template-columns: 1fr 8px 1fr; gap: 0; height: calc(100vh - 112px);
    }
    .panel { background: var(--panel); border: 1px solid var(--border); border-radius: 12px; overflow: hidden; display: flex; flex-direction: column; }
    .panel-head { padding: 8px 12px; font-size: 12px; color: var(--muted); border-bottom: 1px solid var(--border); }
    .panel-body { flex: 1; min-height: 0; overflow: auto; }
    textarea {
      width: 100%; height: 100%;
      background: transparent; color: var(--text); border: 0; outline: none;
      font: 13px/1.7 ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
      padding: 12px; resize: none; caret-color: var(--accent);
      tab-size: 2;
    }
    .preview { padding: 12px 16px; }
    .divider { cursor: col-resize; background: var(--border); }

    /* Prose風 見た目（最低限） */
    .preview :is(h1,h2,h3) { margin-top: 1.2em; }
    .preview h1 { font-size: 1.8rem; }
    .preview h2 { font-size: 1.4rem; }
    .preview h3 { font-size: 1.2rem; }
    .preview p, .preview li, .preview code, .preview pre { font-size: 0.95rem; }
    .preview a { color: #93c5fd; }
    .preview blockquote { border-left: 4px solid #394150; padding-left: 12px; color: #c3c7ce; }
    .preview table { border-collapse: collapse; width: 100%; }
    .preview th, .preview td { border: 1px solid var(--border); padding: 6px 8px; }
    .preview code { background: #20222a; padding: 2px 4px; border-radius: 6px; }
    .preview pre { background: #0c0d10; padding: 12px; border-radius: 10px; overflow: auto; }
    .muted { color: var(--muted); }
    .kicker { font-size: 12px; color: var(--muted); }

    @media (max-width: 900px) {
      .grid { grid-template-columns: 1fr; height: auto; gap: 12px; }
      .divider { display: none; }
    }
  </style>
</head>
<body>
  <header>
    <div class="wrap" style="display:flex; gap: 12px; align-items:center;">
      <div class="title">Markdown Editor（Vanilla JS）</div>
      <div class="kicker" id="themeLabel">テーマ: ダーク</div>
      <div class="spacer"></div>
      <div class="toolbar">
        <!-- ツールバー（Markdownシンタックスの挿入） -->
        <button class="btn" data-action="h1">H1</button>
        <button class="btn" data-action="h2">H2</button>
        <button class="btn" data-action="bold"><b>B</b></button>
        <button class="btn" data-action="italic"><i>I</i></button>
        <button class="btn" data-action="strike">S</button>
        <button class="btn" data-action="code">&lt;/&gt;</button>
        <button class="btn" data-action="list">•</button>
        <button class="btn" data-action="num">1.</button>
        <button class="btn" data-action="quote">&gt;</button>
        <button class="btn" data-action="checkbox">☑</button>
        <button class="btn" data-action="hr">―</button>
        <div class="spacer"></div>
        <button class="btn secondary" id="btnTheme">テーマ切替</button>
        <button class="btn secondary" id="btnExport">書き出し(.md)</button>
        <label class="btn secondary" for="fileIn">読み込み(.md)</label>
        <input id="fileIn" type="file" accept=".md,text/markdown,text/plain" style="display:none" />
        <button class="btn secondary" id="btnCopyHtml">HTMLコピー</button>
        <button class="btn secondary" id="btnSample">サンプル読込</button>
        <button class="btn secondary" id="btnClear">クリア</button>
      </div>
    </div>
  </header>

  <main class="wrap">
    <div class="grid" id="grid">
      <!-- 左ペイン: エディタ -->
      <section class="panel" aria-label="エディタ">
        <div class="panel-head">エディタ（Ctrl/⌘+B:太字, Ctrl/⌘+I:斜体）</div>
        <div class="panel-body">
          <textarea id="area" spellcheck="false" placeholder="ここにMarkdownを書いてください…"></textarea>
        </div>
      </section>

      <!-- 仕切り（ドラッグで幅変更） -->
      <div class="divider" id="divider" role="separator" aria-orientation="vertical" aria-label="サイズ変更バー" tabindex="0"></div>

      <!-- 右ペイン: プレビュー -->
      <section class="panel" aria-label="プレビュー">
        <div class="panel-head">プレビュー <span class="muted">（サニタイズ済み）</span></div>
        <div id="preview" class="panel-body preview"></div>
      </section>
    </div>

    <p class="kicker" style="text-align:center; margin: 10px 0 24px;">AutoSave: localStorage / Export: .md / Import: .md / Copy: HTML</p>
  </main>

  <script>
    // ============================
    // 設定・定数
    // ============================
    const LS_KEY = 'md-editor-content-v1';
    const LS_THEME = 'md-editor-theme-v1';

    // サンプル本文
    const SAMPLE = `# ようこそ Markdown エディタへ ✨\n\n右側にプレビューが表示されます。左側で編集してみましょう。\n\n## 主な機能\n- **太字** / *斜体* / ~~取り消し~~\n- [リンク](https://example.com)\n- コード: `console.log('hello')`\n- 箇条書き\n  - サブ項目\n- 引用\n> 引用はこんな感じ\n\n---\n\nチェックボックス:\n- [ ] やること1\n- [x] 完了したこと\n\n表:\n\n| 見出しA | 見出しB |\n| --- | --- |\n| セル1 | セル2 |\n\n\n\n\n\n`; // 末尾余白でスクロールの感覚をよくする

    // markedの設定（GFM, 改行など）
    marked.setOptions({ gfm: true, breaks: true, headerIds: true, mangle: false });

    // 要素参照
    const area = document.getElementById('area');
    const preview = document.getElementById('preview');
    const themeLabel = document.getElementById('themeLabel');

    // ============================
    // テーマ（ダーク/ライト）
    // ============================
    const applyTheme = (t) => {
      if (t === 'light') {
        document.documentElement.style.setProperty('--bg', '#f6f7f8');
        document.documentElement.style.setProperty('--panel', '#ffffff');
        document.documentElement.style.setProperty('--text', '#0f172a');
        document.documentElement.style.setProperty('--muted', '#657084');
        document.documentElement.style.setProperty('--border', '#e5e7eb');
        document.documentElement.style.setProperty('--accent', '#4f46e5');
        themeLabel.textContent = 'テーマ: ライト';
      } else {
        document.documentElement.style.setProperty('--bg', '#0b0b0c');
        document.documentElement.style.setProperty('--panel', '#111214');
        document.documentElement.style.setProperty('--text', '#e7e7ea');
        document.documentElement.style.setProperty('--muted', '#9aa0a6');
        document.documentElement.style.setProperty('--border', '#2a2c30');
        document.documentElement.style.setProperty('--accent', '#4f46e5');
        themeLabel.textContent = 'テーマ: ダーク';
      }
    };
    const initialTheme = localStorage.getItem(LS_THEME) || 'dark';
    applyTheme(initialTheme);

    document.getElementById('btnTheme').addEventListener('click', () => {
      const next = (localStorage.getItem(LS_THEME) || 'dark') === 'dark' ? 'light' : 'dark';
      localStorage.setItem(LS_THEME, next);
      applyTheme(next);
    });

    // ============================
    // レンダリング（Markdown → HTML → サニタイズ → プレビュー）
    // ============================
    const render = () => {
      const raw = marked.parse(area.value || '');
      const clean = DOMPurify.sanitize(raw);
      preview.innerHTML = clean;
      // コードブロックのハイライト
      if (window.hljs) {
        document.querySelectorAll('pre code').forEach((el) => hljs.highlightElement(el));
      }
    };

    // ============================
    // 入出力（保存/読込/エクスポート/HTMLコピー）
    // ============================
    const save = () => localStorage.setItem(LS_KEY, area.value);
    const load = () => localStorage.getItem(LS_KEY) || SAMPLE;

    const exportMd = () => {
      const blob = new Blob([area.value], { type: 'text/markdown;charset=utf-8' });
      const url = URL.createObjectURL(blob);
      const a = document.createElement('a');
      a.href = url; a.download = 'document.md'; a.click();
      URL.revokeObjectURL(url);
    };

    const importMd = (file) => {
      if (!file) return;
      const reader = new FileReader();
      reader.onload = () => { area.value = String(reader.result || ''); onInput(); };
      reader.readAsText(file);
    };

    const copyHtml = async () => {
      try {
        await navigator.clipboard.writeText(preview.innerHTML);
        alert('HTMLをコピーしました');
      } catch (e) {
        alert('コピーに失敗しました');
      }
    };

    // ============================
    // 編集操作（シンタックス挿入）
    // ============================
    const applySyntax = (fn) => {
      const start = area.selectionStart || 0;
      const end = area.selectionEnd || 0;
      const before = area.value.slice(0, start);
      const sel = area.value.slice(start, end);
      const after = area.value.slice(end);
      const replaced = fn(sel);
      area.value = before + replaced + after;
      const caret = (before + replaced).length;
      area.focus();
      area.setSelectionRange(caret, caret);
      onInput();
    };

    const toolbarActions = {
      h1: (s) => `# ${s || '見出し1'}`,
      h2: (s) => `## ${s || '見出し2'}`,
      bold: (s) => `**${s || '太字'}**`,
      italic: (s) => `*${s || '斜体'}*`,
      strike: (s) => `~~${s || '取り消し'}~~`,
      code: (s) => ``${s || 'code'}``,
      list: (s) => (s || '項目').split('\n').map(l => `- ${l}`).join('\n'),
      num: (s) => (s || '項目').split('\n').map((l,i) => `${i+1}. ${l}`).join('\n'),
      quote: (s) => (s || '引用').split('\n').map(l => `> ${l}`).join('\n'),
      checkbox: (s) => (s || 'やること').split('\n').map(l => `- [ ] ${l}`).join('\n'),
      hr: () => `\n\n---\n\n`,
    };

    document.querySelectorAll('[data-action]').forEach(btn => {
      btn.addEventListener('click', () => {
        const key = btn.getAttribute('data-action');
        const fn = toolbarActions[key];
        if (fn) applySyntax(fn);
      });
    });

    // ============================
    // 入力・ショートカット・ドラッグ&ドロップ
    // ============================
    const onInput = () => { save(); render(); };
    area.addEventListener('input', onInput);

    area.addEventListener('keydown', (e) => {
      const accel = e.metaKey || e.ctrlKey;
      if (!accel) return;
      const k = e.key.toLowerCase();
      if (k === 'b') { e.preventDefault(); applySyntax(toolbarActions.bold); }
      if (k === 'i') { e.preventDefault(); applySyntax(toolbarActions.italic); }
    });

    // ファイル読み込み
    document.getElementById('fileIn').addEventListener('change', (e) => {
      const file = e.target.files && e.target.files[0];
      importMd(file);
      e.target.value = '';
    });

    // ボタン群
    document.getElementById('btnExport').addEventListener('click', exportMd);
    document.getElementById('btnCopyHtml').addEventListener('click', copyHtml);
    document.getElementById('btnSample').addEventListener('click', () => { area.value = SAMPLE; onInput(); });
    document.getElementById('btnClear').addEventListener('click', () => { area.value = ''; onInput(); });

    // ドラッグ&ドロップで.md読込
    area.addEventListener('dragover', (e) => e.preventDefault());
    area.addEventListener('drop', (e) => {
      e.preventDefault();
      const file = e.dataTransfer.files && e.dataTransfer.files[0];
      if (file && /\.md$/i.test(file.name)) importMd(file);
    });

    // 仕切りのドラッグで幅変更
    const divider = document.getElementById('divider');
    const grid = document.getElementById('grid');
    let dragging = false;
    const startDrag = () => dragging = true;
    const stopDrag = () => dragging = false;
    const onMove = (clientX) => {
      const rect = grid.getBoundingClientRect();
      const x = Math.min(Math.max(clientX - rect.left, 180), rect.width - 180); // 最小幅を確保
      grid.style.gridTemplateColumns = `${x}px 8px 1fr`;
    };
    divider.addEventListener('mousedown', (e) => { startDrag(); onMove(e.clientX); });
    window.addEventListener('mousemove', (e) => { if (dragging) onMove(e.clientX); });
    window.addEventListener('mouseup', stopDrag);

    // キーボードでも調整（左右キーで±20px）
    divider.addEventListener('keydown', (e) => {
      if (e.key === 'ArrowLeft' || e.key === 'ArrowRight') {
        e.preventDefault();
        const rect = grid.getBoundingClientRect();
        const cols = getComputedStyle(grid).gridTemplateColumns.split(' ');
        const left = parseFloat(cols[0]);
        const delta = e.key === 'ArrowLeft' ? -20 : 20;
        const next = Math.min(Math.max(left + delta, 180), rect.width - 180);
        grid.style.gridTemplateColumns = `${next}px 8px 1fr`;
      }
    });

    // ============================
    // 初期化
    // ============================
    area.value = load();
    render();
  </script>
</body>
</html>

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

264

265

266

267

268

269

270

271

272

273

274

275

276

277

278

279

280

281

282

283

284

285

286

287

288

289

290

291

292

293

294

295

296

297

298

299

300

301

302

303

304

305

306

307

308

309

310

311

312

313

314

315

316

317

318

319

320

321

322

323

324

325

326

327

328

329

330

331

332

333

334

335

336

337

338

<!doctype html>

<head>

<title>Markdown Editor — Vanilla JS</title>

<style>

/* ざっくりとしたUIスタイル。Tailwind等なしで動作可 */

:root {

--bg: #0b0b0c;

--panel: #111214;

--text: #e7e7ea;

--muted: #9aa0a6;

--border: #2a2c30;

--accent: #4f46e5;

}

* { box-sizing: border-box; }

html, body { height: 100%; }

body {

margin: 0; background: var(--bg); color: var(--text);

font: 14px/1.6 system-ui, -apple-system, Segoe UI, Roboto, "Noto Sans JP", sans-serif;

}

header {

position: sticky; top: 0; z-index: 10;

backdrop-filter: blur(6px);

background: color-mix(in oklab, var(--bg) 80%, transparent);

border-bottom: 1px solid var(--border);

}

.wrap { max-width: 1200px; margin: 0 auto; padding: 12px 16px; }

.title { font-weight: 700; }

.toolbar { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }

.btn {

background: var(--panel); border: 1px solid var(--border); color: var(--text);

padding: 6px 10px; border-radius: 10px; cursor: pointer;

}

.btn:hover { background: #17181b; }

.btn.secondary { color: var(--muted); }

.spacer { flex: 1; }

/* 2カラム: 左エディタ / 右プレビュー（中央ドラッグでサイズ変更） */

.grid {

display: grid; grid-template-columns: 1fr 8px 1fr; gap: 0; height: calc(100vh - 112px);

}

.panel { background: var(--panel); border: 1px solid var(--border); border-radius: 12px; overflow: hidden; display: flex; flex-direction: column; }

.panel-head { padding: 8px 12px; font-size: 12px; color: var(--muted); border-bottom: 1px solid var(--border); }

.panel-body { flex: 1; min-height: 0; overflow: auto; }

textarea {

width: 100%; height: 100%;

background: transparent; color: var(--text); border: 0; outline: none;

font: 13px/1.7 ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;

padding: 12px; resize: none; caret-color: var(--accent);

tab-size: 2;

}

.preview { padding: 12px 16px; }

.divider { cursor: col-resize; background: var(--border); }

/* Prose風見た目（最低限） */

.preview :is(h1,h2,h3) { margin-top: 1.2em; }

.preview h1 { font-size: 1.8rem; }

.preview h2 { font-size: 1.4rem; }

.preview h3 { font-size: 1.2rem; }

.preview p, .preview li, .preview code, .preview pre { font-size: 0.95rem; }

.preview a { color: #93c5fd; }

.preview blockquote { border-left: 4px solid #394150; padding-left: 12px; color: #c3c7ce; }

.preview table { border-collapse: collapse; width: 100%; }

.preview th, .preview td { border: 1px solid var(--border); padding: 6px 8px; }

.preview code { background: #20222a; padding: 2px 4px; border-radius: 6px; }

.preview pre { background: #0c0d10; padding: 12px; border-radius: 10px; overflow: auto; }

.muted { color: var(--muted); }

.kicker { font-size: 12px; color: var(--muted); }

@media (max-width: 900px) {

.grid { grid-template-columns: 1fr; height: auto; gap: 12px; }

.divider { display: none; }

}

</style>

</head>

<body>

<div class="title">Markdown Editor（Vanilla JS）</div>

<button class="btn secondary" id="btnTheme">テーマ切替</button>

<button class="btn secondary" id="btnCopyHtml">HTMLコピー</button>

<button class="btn secondary" id="btnSample">サンプル読込</button>

</div>

</header>

</div>

</section>

<div class="panel-head">プレビュー <span class="muted">（サニタイズ済み）</span></div>

</section>

</div>

<p class="kicker" style="text-align:center; margin: 10px 0 24px;">AutoSave: localStorage / Export: .md / Import: .md / Copy: HTML</p>

</main>

// ============================

// 設定・定数

// ============================

const LS_KEY = 'md-editor-content-v1';

const LS_THEME = 'md-editor-theme-v1';

// サンプル本文

const SAMPLE = `# ようこそ Markdown エディタへ ✨\n\n右側にプレビューが表示されます。左側で編集してみましょう。\n\n## 主な機能\n- **太字** / *斜体* / ~~取り消し~~\n- [リンク](https://example.com)\n- コード: `console.log('hello')`\n- 箇条書き\n - サブ項目\n- 引用\n> 引用はこんな感じ\n\n---\n\nチェックボックス:\n- [ ] やること1\n- [x] 完了したこと\n\n表:\n\n| 見出しA | 見出しB |\n| --- | --- |\n| セル1 | セル2 |\n\n\n\n\n\n`; // 末尾余白でスクロールの感覚をよくする

// markedの設定（GFM, 改行など）

marked.setOptions({ gfm: true, breaks: true, headerIds: true, mangle: false });

// 要素参照

const area = document.getElementById('area');

const preview = document.getElementById('preview');

const themeLabel = document.getElementById('themeLabel');

// ============================

// テーマ（ダーク/ライト）

// ============================

const applyTheme = (t) => {

if (t === 'light') {

document.documentElement.style.setProperty('--bg', '#f6f7f8');

document.documentElement.style.setProperty('--panel', '#ffffff');

document.documentElement.style.setProperty('--text', '#0f172a');

document.documentElement.style.setProperty('--muted', '#657084');

document.documentElement.style.setProperty('--border', '#e5e7eb');

document.documentElement.style.setProperty('--accent', '#4f46e5');

themeLabel.textContent = 'テーマ: ライト';

} else {

document.documentElement.style.setProperty('--bg', '#0b0b0c');

document.documentElement.style.setProperty('--panel', '#111214');

document.documentElement.style.setProperty('--text', '#e7e7ea');

document.documentElement.style.setProperty('--muted', '#9aa0a6');

document.documentElement.style.setProperty('--border', '#2a2c30');

document.documentElement.style.setProperty('--accent', '#4f46e5');

themeLabel.textContent = 'テーマ: ダーク';

}

};

const initialTheme = localStorage.getItem(LS_THEME) || 'dark';

applyTheme(initialTheme);

document.getElementById('btnTheme').addEventListener('click', () => {

const next = (localStorage.getItem(LS_THEME) || 'dark') === 'dark' ? 'light' : 'dark';

localStorage.setItem(LS_THEME, next);

applyTheme(next);

});

// ============================

// レンダリング（Markdown → HTML → サニタイズ → プレビュー）

// ============================

const render = () => {

const raw = marked.parse(area.value || '');

const clean = DOMPurify.sanitize(raw);

preview.innerHTML = clean;

// コードブロックのハイライト

if (window.hljs) {

document.querySelectorAll('pre code').forEach((el) => hljs.highlightElement(el));

}

};

// ============================

// 入出力（保存/読込/エクスポート/HTMLコピー）

// ============================

const save = () => localStorage.setItem(LS_KEY, area.value);

const load = () => localStorage.getItem(LS_KEY) || SAMPLE;

const exportMd = () => {

const blob = new Blob([area.value], { type: 'text/markdown;charset=utf-8' });

const url = URL.createObjectURL(blob);

const a = document.createElement('a');

a.href = url; a.download = 'document.md'; a.click();

URL.revokeObjectURL(url);

};

const importMd = (file) => {

if (!file) return;

const reader = new FileReader();

reader.onload = () => { area.value = String(reader.result || ''); onInput(); };

reader.readAsText(file);

};

const copyHtml = async () => {

try {

await navigator.clipboard.writeText(preview.innerHTML);

alert('HTMLをコピーしました');

} catch (e) {

alert('コピーに失敗しました');

}

};

// ============================

// 編集操作（シンタックス挿入）

// ============================

const applySyntax = (fn) => {

const start = area.selectionStart || 0;

const end = area.selectionEnd || 0;

const before = area.value.slice(0, start);

const sel = area.value.slice(start, end);

const after = area.value.slice(end);

const replaced = fn(sel);

area.value = before + replaced + after;

const caret = (before + replaced).length;

area.focus();

area.setSelectionRange(caret, caret);

onInput();

};

const toolbarActions = {

h1: (s) => `# ${s || '見出し1'}`,

h2: (s) => `## ${s || '見出し2'}`,

bold: (s) => `**${s || '太字'}**`,

italic: (s) => `*${s || '斜体'}*`,

strike: (s) => `~~${s || '取り消し'}~~`,

code: (s) => ``${s || 'code'}``,

list: (s) => (s || '項目').split('\n').map(l => `- ${l}`).join('\n'),

num: (s) => (s || '項目').split('\n').map((l,i) => `${i+1}. ${l}`).join('\n'),

quote: (s) => (s || '引用').split('\n').map(l => `> ${l}`).join('\n'),

checkbox: (s) => (s || 'やること').split('\n').map(l => `- [ ] ${l}`).join('\n'),

hr: () => `\n\n---\n\n`,

};

document.querySelectorAll('[data-action]').forEach(btn => {

btn.addEventListener('click', () => {

const key = btn.getAttribute('data-action');

const fn = toolbarActions[key];

if (fn) applySyntax(fn);

});

// ============================

// 入力・ショートカット・ドラッグ&ドロップ

// ============================

const onInput = () => { save(); render(); };

area.addEventListener('input', onInput);

area.addEventListener('keydown', (e) => {

const accel = e.metaKey || e.ctrlKey;

if (!accel) return;

const k = e.key.toLowerCase();

if (k === 'b') { e.preventDefault(); applySyntax(toolbarActions.bold); }

if (k === 'i') { e.preventDefault(); applySyntax(toolbarActions.italic); }

});

// ファイル読み込み

document.getElementById('fileIn').addEventListener('change', (e) => {

const file = e.target.files && e.target.files[0];

importMd(file);

e.target.value = '';

});

// ボタン群

document.getElementById('btnExport').addEventListener('click', exportMd);

document.getElementById('btnCopyHtml').addEventListener('click', copyHtml);

document.getElementById('btnSample').addEventListener('click', () => { area.value = SAMPLE; onInput(); });

document.getElementById('btnClear').addEventListener('click', () => { area.value = ''; onInput(); });

// ドラッグ&ドロップで.md読込

area.addEventListener('dragover', (e) => e.preventDefault());

area.addEventListener('drop', (e) => {

e.preventDefault();

const file = e.dataTransfer.files && e.dataTransfer.files[0];

if (file && /\.md$/i.test(file.name)) importMd(file);

});

// 仕切りのドラッグで幅変更

const divider = document.getElementById('divider');

const grid = document.getElementById('grid');

let dragging = false;

const startDrag = () => dragging = true;

const stopDrag = () => dragging = false;

const onMove = (clientX) => {

const rect = grid.getBoundingClientRect();

const x = Math.min(Math.max(clientX - rect.left, 180), rect.width - 180); // 最小幅を確保

grid.style.gridTemplateColumns = `${x}px 8px 1fr`;

};

divider.addEventListener('mousedown', (e) => { startDrag(); onMove(e.clientX); });

window.addEventListener('mousemove', (e) => { if (dragging) onMove(e.clientX); });

window.addEventListener('mouseup', stopDrag);

// キーボードでも調整（左右キーで±20px）

divider.addEventListener('keydown', (e) => {

if (e.key === 'ArrowLeft' || e.key === 'ArrowRight') {

e.preventDefault();

const rect = grid.getBoundingClientRect();

const cols = getComputedStyle(grid).gridTemplateColumns.split(' ');

const left = parseFloat(cols[0]);

const delta = e.key === 'ArrowLeft' ? -20 : 20;

const next = Math.min(Math.max(left + delta, 180), rect.width - 180);

grid.style.gridTemplateColumns = `${next}px 8px 1fr`;

}

});

// ============================

// 初期化

// ============================

area.value = load();

render();

</script>

</body>

</html>

関連記事