Branch Picker

'use client'

import { useRef, useState } from 'react'
import './branch-picker.css'

export interface Branch { name: string; ahead: number; behind: number; recent?: boolean }

export interface BranchPickerProps {
  branches: Branch[]
  tags?: string[]
  value?: string
  defaultBranch?: string
  defaultOpen?: boolean
  onChange?: (name: string) => void
  fill?: 'dark' | 'light'
  className?: string
}

const BrIcon = () => <svg viewBox="0 0 16 16" aria-hidden><circle cx="4" cy="3.5" r="1.7" /><circle cx="4" cy="12.5" r="1.7" /><circle cx="12" cy="5" r="1.7" /><path d="M4 5.2v5.6M12 6.7c0 3-4 2.3-7.3 4.6" /></svg>
const Check = () => <svg viewBox="0 0 16 16" aria-hidden><path d="M3 8.5l3 3 7-7" /></svg>

/** Git branch and tag switcher with create. */
export function BranchPicker({ branches, tags = [], value = 'main', defaultBranch = 'main', defaultOpen = false, onChange, fill = 'dark', className }: BranchPickerProps) {
  const [list, setList] = useState(branches)
  const [cur, setCur] = useState(value)
  const [open, setOpen] = useState(defaultOpen)
  const [q, setQ] = useState('')
  const [tab, setTab] = useState<'branches' | 'tags'>('branches')
  const [act, setAct] = useState(0)
  const trig = useRef<HTMLButtonElement>(null)
  const pool = tab === 'branches' ? list.map((b) => b.name) : tags
  const hits = pool.filter((n) => n.toLowerCase().includes(q.trim().toLowerCase()))
  const recent = tab === 'branches' && !q ? list.filter((b) => b.recent).map((b) => b.name) : []
  const rest = hits.filter((n) => !recent.includes(n))
  const create = tab === 'branches' && q.trim() && !pool.includes(q.trim()) ? q.trim().replace(/\s+/g, '-') : null
  const rows = [...(create ? [`+${create}`] : []), ...recent, ...rest]
  const choose = (row: string) => {
    if (row.startsWith('+')) { const n = row.slice(1); setList((l) => [{ name: n, ahead: 0, behind: 0, recent: true }, ...l]); setCur(n); onChange?.(n) }
    else { setCur(row); onChange?.(row) }
    setOpen(false); setQ(''); trig.current?.focus()
  }
  const meta = (n: string) => list.find((b) => b.name === n)
  const opt = (row: string, i: number) => {
    const isNew = row.startsWith('+'), n = isNew ? row.slice(1) : row, m = meta(n)
    return (
      <li key={row} id={`sd-brp-${i}`} role="option" aria-selected={cur === n} className="sd-brp__o" data-act={act === i || undefined} onMouseEnter={() => setAct(i)} onClick={() => choose(row)}>
        {cur === n ? <Check /> : <BrIcon />}
        <span>{isNew ? <>Create <b>{n}</b> from {cur}</> : n}</span>
        {n === defaultBranch && !isNew && <em>default</em>}
        {m && !isNew && n !== defaultBranch && <small>{m.ahead}↑ {m.behind}↓</small>}
      </li>
    )
  }
  return (
    <div className={['sd-brp', className].filter(Boolean).join(' ')} data-fill={fill}>
      <button ref={trig} type="button" className="sd-brp__tr" aria-haspopup="listbox" aria-expanded={open} onClick={() => setOpen((o) => !o)}><BrIcon /><span>{cur}</span>▾</button>
      {open && (
        <div className="sd-brp__p">
          <input autoFocus role="combobox" aria-expanded aria-controls="sd-brp-list" aria-activedescendant={`sd-brp-${act}`} aria-label="Find or create a branch" placeholder="Find or create a branch…" value={q}
            onChange={(e) => { setQ(e.target.value); setAct(0) }}
            onKeyDown={(e) => {
              if (e.key === 'ArrowDown') { e.preventDefault(); setAct((a) => Math.min(rows.length - 1, a + 1)) }
              else if (e.key === 'ArrowUp') { e.preventDefault(); setAct((a) => Math.max(0, a - 1)) }
              else if (e.key === 'Enter' && rows[act]) { e.preventDefault(); choose(rows[act]) }
              else if (e.key === 'Escape') { setOpen(false); trig.current?.focus() }
            }} />
          <div className="sd-brp__tabs" role="tablist">{(['branches', 'tags'] as const).map((t) => <button key={t} type="button" role="tab" aria-selected={tab === t} onClick={() => { setTab(t); setAct(0) }}>{t[0].toUpperCase() + t.slice(1)}</button>)}</div>
          <ul id="sd-brp-list" role="listbox" aria-label={tab}>
            {create && opt(`+${create}`, 0)}
            {recent.length > 0 && <li className="sd-brp__h" role="presentation">Recent</li>}
            {recent.map((r, i) => opt(r, i + (create ? 1 : 0)))}
            {recent.length > 0 && rest.length > 0 && <li className="sd-brp__h" role="presentation">All</li>}
            {rest.map((r, i) => opt(r, i + recent.length + (create ? 1 : 0)))}
            {!rows.length && <li className="sd-brp__none">Nothing matches</li>}
          </ul>
        </div>
      )}
    </div>
  )
}

.sd-brp { --bg: #1c1c1c; --fg: #f6f6f6; --mute: #8e8e8e; --line: rgb(255 255 255 / 0.1); --soft: rgb(255 255 255 / 0.07); --strong: #fafafa; --on: #111; 
  color: var(--fg); font-size: 14px; line-height: 1.4; -webkit-tap-highlight-color: transparent; }
.sd-brp[data-fill='light'] { --bg: #fff; --fg: #121212; --mute: #6f6f6f; --line: rgb(0 0 0 / 0.09); --soft: rgb(0 0 0 / 0.05); --strong: #111; --on: #fff; }
.sd-brp :where(button) { font: inherit; color: inherit; background: none; border: 0; padding: 0; cursor: pointer; }
.sd-brp :focus-visible { outline: 2px solid var(--fg); outline-offset: 2px; }
.sd-brp .sr { position: absolute; width: 1px; height: 1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; }
.sd-brp { position: relative; width: min(100%, 320px); }
.sd-brp__tr { display: flex; align-items: center; gap: 8px; height: 38px; padding: 0 12px; border-radius: 10px; box-shadow: inset 0 0 0 1px var(--line); background: var(--bg) !important; font: 12.5px ui-monospace, monospace; }
.sd-brp__tr svg, .sd-brp__o svg { width: 14px; height: 14px; fill: none; stroke: currentColor; stroke-width: 1.8; flex: none; }
.sd-brp__tr span { flex: 1; text-align: left; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.sd-brp__p { margin-top: 6px; grid-template-columns: minmax(0, 1fr); border-radius: 18px; background: var(--bg); box-shadow: inset 0 0 0 1px var(--line); overflow: hidden; animation: sd-brp-in 160ms ease-out; }
@keyframes sd-brp-in { from { opacity: 0; transform: translateY(-4px); } }
.sd-brp__p input { width: 100%; height: 38px; padding: 0 12px; border: 0; border-bottom: 1px solid var(--line); background: none; color: var(--fg); font: 12.5px ui-monospace, monospace; outline: 0; box-sizing: border-box; }
.sd-brp__tabs { display: flex; gap: 14px; padding: 0 12px; border-bottom: 1px solid var(--line); }
.sd-brp__tabs button { padding: 7px 0; font-size: 12px; color: var(--mute) !important; box-shadow: inset 0 -2px 0 transparent; }
.sd-brp__tabs button[aria-selected='true'] { color: var(--fg) !important; box-shadow: inset 0 -2px 0 var(--fg); }
.sd-brp ul { list-style: none; margin: 0; padding: 4px; max-height: 220px; overflow-y: auto; }
.sd-brp__h { padding: 6px 8px 2px; font-size: 10.5px; color: var(--mute); text-transform: uppercase; letter-spacing: 0.06em; }
.sd-brp__o { display: flex; align-items: center; gap: 8px; padding: 7px 8px; border-radius: 7px; font: 12.5px ui-monospace, monospace; cursor: pointer; }
.sd-brp__o[data-act] { background: var(--soft); }
.sd-brp__o span { flex: 1; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.sd-brp__o small { font: 10.5px ui-sans-serif, system-ui; color: var(--mute); font-variant-numeric: tabular-nums; }
.sd-brp__o em { font: 600 11px ui-sans-serif, system-ui; font-style: normal; padding: 1px 6px; border-radius: 99px; box-shadow: inset 0 0 0 1px var(--line); }
.sd-brp__o[aria-selected='true'] svg { stroke-width: 2.6; }
.sd-brp__none { padding: 16px 8px; text-align: center; font-size: 12px; color: var(--mute); }
@media (prefers-reduced-motion: reduce) { .sd-brp *, .sd-brp *::before, .sd-brp *::after { animation: none !important; transition: none !important; } }