feat: extract quality switching and mode selection

static/player/quality.ts

@@ -0,0 +1,59 @@
+import { state } from './state'
+import { displayTimeFromAbsolute, absoluteTimeFromDisplay } from './timeline'
+
+const streamUrlForMode = (mode: string, quality?: string): string => {
+  const src = state.modeSources[mode]
+  if (!src?.token) return ''
+  let url = `${state.streamURL}?mode=${encodeURIComponent(mode)}&token=${encodeURIComponent(src.token)}`
+  if (quality && quality !== 'best') url += `&quality=${encodeURIComponent(quality)}`
+  return url
+}
+
+const loadVideo = (url: string): void => {
+  if (!url) return
+  const wasPlaying = !state.video.paused
+  const prevTime = displayTimeFromAbsolute(state.video.currentTime)
+  state.video.src = url
+  state.video.load()
+  state.pendingSeekTime = prevTime
+  if (wasPlaying) state.video.play().catch(() => {})
+}
+
+export const switchQuality = (quality: string): void => {
+  const url = streamUrlForMode(state.currentMode, quality)
+  if (!url) return
+  localStorage.setItem('mal:preferred-quality', quality)
+  loadVideo(url)
+}
+
+export const updateQualityOptions = (): void => {
+  const select = state.container.querySelector('[data-quality-select]') as HTMLSelectElement | null
+  if (!select) return
+  const qualities = state.modeSources[state.currentMode]?.qualities ?? []
+  select.innerHTML = ''
+
+  const best = document.createElement('option')
+  best.value = 'best'
+  best.textContent = 'Auto / Best'
+  select.appendChild(best)
+
+  qualities.forEach(q => {
+    const opt = document.createElement('option')
+    opt.value = q
+    opt.textContent = q
+    select.appendChild(opt)
+  })
+
+  const preferred = localStorage.getItem('mal:preferred-quality') || 'best'
+  select.value = qualities.includes(preferred) ? preferred : 'best'
+
+  const wrapper = select.parentElement
+  wrapper?.classList.toggle('hidden', qualities.length === 0)
+}
+
+export const setupQuality = (): void => {
+  const select = state.container.querySelector('[data-quality-select]') as HTMLSelectElement | null
+  select?.addEventListener('change', (e) => {
+    switchQuality((e.target as HTMLSelectElement).value)
+  })
+}