Indent stuff

pico.js

     const S = `0${dt.getSeconds()}`.slice(-2)
     return `${H}:${M}:${S}`
 }
+const blockIndent = (text, iStart, iEnd, nLevels) => {
+    // prop
+    const startLine = text.slice(0, iStart).split('\n').length - 1
+    const endLine = text.slice(0, iEnd).split('\n').length - 1
+    const newText = text
+        .split('\n')
+        .map((line, i) => {
+            if(i < startLine || i > endLine || nLevels === 0) {
+                newLine = line
+            }
+            else if(nLevels > 0) {
+                newLine = line.replace(/^/, '    ')
+            }
+            else if(nLevels < 0) {
+                newLine = line.replace(/^    /, '')
+            }
+
+            if(i === startLine) {
+                iStart = iStart + newLine.length - line.length
+            }
+            iEnd = iEnd + newLine.length - line.length
+            return newLine
+        })
+        .join('\n')
+    return [newText, Math.max(0, iStart), Math.max(0, iEnd)]
+}
 const hotKey = (e) => {
     // if isDesktop, Enter posts, unless Shift+Enter
     // use isLandscape as proxy for isDesktop
         e.preventDefault()
         Chat.sendPost()
     }
+    // indent and dedent
+    const modKey = e.ctrlKey || e.metaKey
+    const {value: text, selectionStart: A, selectionEnd: B} = textbox
+    if(e.key === 'Tab') {
+        e.preventDefault()
+        const regex = new RegExp(`([\\s\\S]{${A}})([\\s\\S]{${B - A}})`)
+        textbox.value = text.replace(regex, (m, a, b) => a + ' '.repeat(4))
+        textbox.setSelectionRange(A + 4, A + 4)
+    }
+    if(']['.includes(e.key) && modKey) {
+        e.preventDefault()
+        const nLevels = {']': 1, '[': -1}[e.key]
+        const [newText, newA, newB] = blockIndent(text, A, B, nLevels)
+        textbox.value = newText
+        textbox.setSelectionRange(newA, newB)
+    }
 }
 const Video = {
     appendStream: ({username, stream}) => ({dom}) => {