Braille Progress

"use client"

import * as React from "react"
import { BrailleProgress } from "@/components/ui/braille-progress"

const FIT_CSS = "html,body{overflow:hidden}[data-fit-small] [data-fit-hide]{display:none!important}"

/**
 * 21st shows a demo in a small frame: about 674 by 421 on a component page, 358 by 224 on a
 * phone and 245 by 139 on a profile card. A demo taller than its frame gets scrollbars, which
 * render white on dark pages. FitFrame fills the frame exactly instead.
 *
 * - "scale": the content shrinks until it fits, centered. For visuals such as orbs.
 * - "crop": the content stays at full size from the top and fades out at the bottom. For text
 *   that streams in, where a changing scale would make the page breathe.
 *
 * `minWidth` lays out a wide demo (a table, a two column panel) at that width and scales it down
 * to the frame, instead of letting it collapse to a narrow layout. The frame centers it, so it
 * shrinks evenly on both sides.
 *
 * Anything marked `data-fit-hide` (state buttons, the chatcn.dev line) drops out in frames
 * shorter than `hideBelow`, so a profile card shows the visual alone.
 */
function FitFrame({
  children,
  mode = "scale",
  hideBelow = 360,
  minWidth,
}: {
  children: React.ReactNode
  mode?: "scale" | "crop"
  hideBelow?: number
  minWidth?: string
}) {
  const content = React.useRef<HTMLDivElement>(null)
  const [cropped, setCropped] = React.useState(false)

  React.useLayoutEffect(() => {
    const el = content.current
    if (!el) return
    const measure = () => {
      const vw = window.innerWidth
      const vh = window.innerHeight
      el.toggleAttribute("data-fit-small", vh < hideBelow)
      // Layout sizes ignore the transform, so measuring never feeds back.
      const w = Math.max(el.offsetWidth, el.scrollWidth)
      const h = Math.max(el.offsetHeight, el.scrollHeight)
      const scale = mode === "scale" ? Math.min(1, vw / w, vh / h) : 1
      el.style.transform = scale < 1 ? `scale(${scale})` : ""
      setCropped(mode === "crop" && h > vh + 1)
    }
    measure()
    const observer = new ResizeObserver(measure)
    observer.observe(el)
    window.addEventListener("resize", measure)
    return () => {
      observer.disconnect()
      window.removeEventListener("resize", measure)
    }
  }, [mode, hideBelow])

  const fade = "linear-gradient(to bottom, #000 calc(100% - 40px), transparent)"
  return (
    <div
      className="flex w-full justify-center overflow-hidden"
      style={{
        height: "100dvh",
        alignItems: mode === "crop" ? "flex-start" : "center",
        maskImage: cropped ? fade : undefined,
        WebkitMaskImage: cropped ? fade : undefined,
      }}
    >
      <style>{FIT_CSS}</style>
      <div
        ref={content}
        className="w-full shrink-0"
        style={{ transformOrigin: mode === "crop" ? "top center" : "center", minWidth }}
      >
        {children}
      </div>
    </div>
  )
}

const FILES = [
  { name: "unet.safetensors", size: "3.4 GB", rate: 0.9 },
  { name: "text_encoder.safetensors", size: "1.4 GB", rate: 1.5 },
  { name: "vae.safetensors", size: "335 MB", rate: 2.8 },
  { name: "scheduler.json", size: "14 KB", rate: 6 },
  { name: "tokenizer.json", size: "2.1 MB", rate: 9 },
]

/** The line under each 21st demo that points back to the kit. */
function MoreOn({ slug, children }: { slug: string; children: React.ReactNode }) {
  return (
    <p data-fit-hide className="text-[0.75rem]/[1rem] text-(color:--chatcn-fg-faint) text-center text-balance">
      {children}{" "}
      <a
        href={`https://chatcn.dev/docs/components/${slug}`}
        target="_blank"
        rel="noopener"
        className="text-(color:--chatcn-fg-subtle) hover:text-(color:--chatcn-fg) underline underline-offset-2"
      >
        chatcn.dev
      </a>
    </p>
  )
}

/**
 * Weights downloading in a terminal, each bar moving at eight steps per character, while the
 * resolver line runs with no known length. The pull starts over once every file is in.
 */
export default function BrailleProgressPreview() {
  const [t, setT] = React.useState(0)
  React.useEffect(() => {
    if (window.matchMedia("(prefers-reduced-motion: reduce)").matches) {
      setT(60)
      return
    }
    const id = window.setInterval(() => setT((v) => (v >= 75 ? 0 : v + 1)), 40)
    return () => window.clearInterval(id)
  }, [])
  const resolved = t > 12

  return (
    <FitFrame minWidth="44rem">
      <div className="flex w-full flex-col items-center justify-center gap-6 p-6">
        <div className="bg-(color:--chatcn-inset) rounded-(--chatcn-radius-xl) shadow-(--chatcn-shadow-border) text-[0.8125rem]/[1.25rem] w-full max-w-2xl p-5 font-mono leading-6">
          <p className="text-(color:--chatcn-fg-subtle)">$ pull image-model --weights fp16</p>
          <div className="mt-2 flex flex-col">
            <div className="flex min-w-0 items-baseline gap-[1ch]">
              <BrailleProgress
                value={resolved ? 100 : undefined}
                label={
                  <span className="inline-block w-[25ch] align-bottom">resolving manifest</span>
                }
                width={24}
                className="min-w-0"
              />
            </div>
            {FILES.map((f) => (
              <div key={f.name} className="flex min-w-0 items-baseline gap-[1ch]">
                <BrailleProgress
                  value={Math.max(0, Math.min(100, (t - 12) * f.rate * 1.9))}
                  label={
                    <span className="inline-block w-[25ch] truncate align-bottom">{f.name}</span>
                  }
                  width={24}
                  className="min-w-0"
                />
                <span className="text-(color:--chatcn-fg-subtle) ms-auto shrink-0">{f.size}</span>
              </div>
            ))}
          </div>
        </div>
        <MoreOn slug="braille-progress">Real text, eight steps per character. On</MoreOn>
      </div>
    </FitFrame>
  )
}