/**
 * Ice-scene bubbles: the glossy orbs (and Aero's bubbles) must rise through
 * the open band — clear of the header, the bottom chrome and the desktop
 * rail — with sway + slight scale, fade in and out inside it so no visible
 * float ever touches the band's clip, animate only transform/opacity on their
 * own composited layers, stay behind everything, park under reduced motion,
 * while the tab is hidden, while the window has no focus and under a dialog
 * scrim, and keep the per-breakpoint count (5 desktop / 3 tablet / 2 phones).
 * The cost contract rides along: no mask on the animated layer, no blend-mode
 * grain, static blobs, and no backdrop blur on glass that sits still.
 */
import { BASE, DECK, launchBrowser, makeChecker, makePage, seed } from "./lib.mjs";

const { check, finish } = makeChecker();
const browser = await launchBrowser();

/** Reads the phase-1 orb's rendered state after parking its animation there.
    CSS animations render at (currentTime - delay), and the delay is negative,
    so the requested phase has to be offset by it. */
async function orbAt(page, phase) {
  return page.evaluate(async (phase) => {
    const orb = document.querySelector(".ice-orb-1");
    const animation = orb.getAnimations().find((entry) => entry.animationName === "ice-rise");
    const timing = animation.effect.getTiming();
    animation.pause();
    // Chrome ignores a negative currentTime, so wrap into the loop.
    const wanted = phase * timing.duration + (timing.delay ?? 0);
    animation.currentTime = ((wanted % timing.duration) + timing.duration) % timing.duration;
    await new Promise((resolve) => requestAnimationFrame(() => requestAnimationFrame(resolve)));
    const rect = orb.getBoundingClientRect();
    const band = document.querySelector(".ice-floats").getBoundingClientRect();
    return {
      top: rect.top,
      bottom: rect.bottom,
      left: rect.left,
      width: rect.width,
      opacity: Number(getComputedStyle(orb).opacity),
      band: { top: band.top, bottom: band.bottom, left: band.left },
    };
  }, phase);
}

/** Parks every displayed float matching `selector` at 41 phases of its pass
    and lists the frames where a visible one (opacity > 0.05) pokes out of the
    band — the band's top, its bottom and, where it starts right of the
    viewport edge, its left side (the rail). Those are the frames where the
    clip would slice a bubble. */
async function sweep(page, selector) {
  return page.evaluate(async (selector) => {
    const band = document.querySelector(".ice-floats").getBoundingClientRect();
    const floats = [...document.querySelectorAll(selector)].filter((el) => getComputedStyle(el).display !== "none");
    const animations = floats.map((el) => {
      const animation = el.getAnimations()[0];
      animation.pause();
      return animation;
    });
    const misses = [];
    let samples = 0;
    for (let step = 0; step <= 40; step += 1) {
      const phase = step / 40;
      for (const animation of animations) {
        const timing = animation.effect.getTiming();
        const wanted = phase * timing.duration + (timing.delay ?? 0);
        animation.currentTime = ((wanted % timing.duration) + timing.duration) % timing.duration;
      }
      await new Promise((resolve) => requestAnimationFrame(resolve));
      floats.forEach((el) => {
        const opacity = Number(getComputedStyle(el).opacity);
        if (opacity <= 0.05) return;
        samples += 1;
        const rect = el.getBoundingClientRect();
        const out =
          rect.top < band.top - 2 || rect.bottom > band.bottom + 2 || (band.left > 0 && rect.left < band.left - 2);
        if (out) misses.push(`${el.className} @${phase}: ${Math.round(rect.top)}-${Math.round(rect.bottom)} x${Math.round(rect.left)} (${opacity.toFixed(2)})`);
      });
    }
    return { floats: floats.length, samples, misses };
  }, selector);
}

/* 1. scene contract (desktop) ---------------------------------------- */
{
  const { context, page } = await makePage(browser, { width: 1280, height: 900, deviceScaleFactor: 1 });
  await seed(page, { decks: [DECK] });
  await page.goto(BASE, { waitUntil: "networkidle" });
  await page.waitForTimeout(1200);

  const scene = await page.evaluate(() => {
    const element = document.querySelector(".ice-scene");
    const style = getComputedStyle(element);
    return {
      position: style.position,
      zIndex: style.zIndex,
      pointerEvents: style.pointerEvents,
      overflow: style.overflow,
      ariaHidden: element.getAttribute("aria-hidden"),
    };
  });
  check("scene: fixed, z-index -1, no pointer events, clipped", scene.position === "fixed" && scene.zIndex === "-1" && scene.pointerEvents === "none" && scene.overflow === "hidden");
  check("scene: hidden from assistive tech", scene.ariaHidden === "true");

  const orbs = await page.evaluate(() =>
    [...document.querySelectorAll(".ice-orb")].map((orb) => {
      const style = getComputedStyle(orb);
      return {
        animation: style.animationName,
        willChange: style.willChange,
        filter: style.filter,
        backdropFilter: style.backdropFilter || style.webkitBackdropFilter,
        duration: parseFloat(style.animationDuration),
        delay: style.animationDelay,
        opacity: Number(style.opacity),
      };
    }),
  );
  check("orbs: five on desktop, all running the rise", orbs.length === 5 && orbs.every((orb) => orb.animation === "ice-rise"));
  check("orbs: will-change transform, no filter/backdrop-filter", orbs.every((orb) => orb.willChange === "transform" && orb.filter === "none" && (orb.backdropFilter === "none" || !orb.backdropFilter)));
  check("orbs: negative delays spread them on load", orbs.every((orb) => orb.delay.startsWith("-")));
  check("orbs: own duration per pass (30-70s, 5 distinct)", orbs.every((orb) => orb.duration >= 30 && orb.duration <= 70) && new Set(orbs.map((orb) => orb.duration)).size === 5, orbs.map((orb) => orb.duration).join(","));
  check("orbs: reduced opacity token applied", orbs.every((orb) => orb.opacity > 0.3 && orb.opacity < 0.45), String(orbs[0]?.opacity));

  /* The floats layer: orbs + bubbles live in one wrapper that is the open
     band between the chrome — a plain rectangular clip, never a mask (a mask
     re-renders the whole animated layer offscreen on every frame). */
  const floats = await page.evaluate(() => {
    const layer = document.querySelector(".ice-floats");
    const style = layer ? getComputedStyle(layer) : null;
    const rect = layer?.getBoundingClientRect();
    return {
      children: layer ? layer.children.length : 0,
      orbs: document.querySelectorAll(".ice-floats .ice-orb").length,
      bubbles: document.querySelectorAll(".ice-floats .ice-bubble").length,
      mask: style ? style.maskImage || style.webkitMaskImage || "none" : "",
      overflow: style?.overflow,
      top: rect?.top,
      bottom: rect?.bottom,
      left: rect?.left,
      right: rect?.right,
      viewport: { width: document.documentElement.clientWidth, height: window.innerHeight },
    };
  });
  check(
    "floats: orbs and bubbles ride one layer",
    floats.children === 23 && floats.orbs === 5 && floats.bubbles === 18,
    JSON.stringify(floats),
  );
  check("floats: a plain clip, no mask on the animated layer", floats.mask === "none" && floats.overflow === "hidden", `${floats.mask} / ${floats.overflow}`);
  check(
    "floats: the band clears the header, the bottom chrome and the rail",
    floats.top === 68 && floats.viewport.height - floats.bottom === 151 && floats.left === 268 && floats.right === floats.viewport.width,
    JSON.stringify(floats),
  );

  const keyframes = await page.evaluate(() => {
    for (const sheet of document.styleSheets) {
      try {
        for (const rule of sheet.cssRules) {
          if (rule instanceof CSSKeyframesRule && rule.name === "ice-rise") {
            return [...rule.cssRules].map((frame) => ({ offset: frame.keyText, props: [...frame.style] }));
          }
        }
      } catch {
        /* cross-origin sheet */
      }
    }
    return null;
  });
  check("keyframes: only transform + opacity animate", Boolean(keyframes) && keyframes.every((frame) => frame.props.every((prop) => prop === "transform" || prop === "opacity")), JSON.stringify(keyframes?.map((frame) => frame.props)));
  const fadeIn = keyframes?.find((frame) => frame.offset === "0%");
  const fadeOut = keyframes?.find((frame) => frame.offset === "100%");
  check("keyframes: fade to 0 at both edges", fadeIn?.props.includes("opacity") && fadeOut?.props.includes("opacity"));

  const start = await orbAt(page, 0.01);
  const lower = await orbAt(page, 0.2);
  const mid = await orbAt(page, 0.5);
  const upper = await orbAt(page, 0.8);
  const end = await orbAt(page, 0.99);
  check(
    "rise: starts at the band's bottom, ends at its top",
    Math.abs(start.bottom - start.band.bottom) < 8 && Math.abs(end.top - end.band.top) < 12,
    `start ${Math.round(start.bottom)}/${start.band.bottom}, end ${Math.round(end.top)}/${end.band.top}`,
  );
  check("rise: moves upward the whole way", lower.top < start.top && mid.top < lower.top && upper.top < mid.top && end.top < upper.top);
  check("sway: swings across the path", Math.abs(mid.left - lower.left) > 30 && Math.abs(upper.left - mid.left) > 15, `${Math.round(lower.left)} → ${Math.round(mid.left)} → ${Math.round(upper.left)}`);
  check("scale: drifts slightly across the pass", end.width > start.width + 8, `${start.width.toFixed(1)} → ${end.width.toFixed(1)}`);
  check("fade: in at the bottom, out at the top, full between", start.opacity < 0.1 && mid.opacity > 0.3 && end.opacity < 0.1, `${start.opacity} / ${mid.opacity} / ${end.opacity}`);

  const swept = await sweep(page, ".ice-orb");
  check(
    "band: a visible orb never touches its edges (nothing to slice)",
    swept.floats === 5 && swept.samples > 100 && swept.misses.length === 0,
    swept.misses.slice(0, 3).join(" | ") || `${swept.samples} visible frames`,
  );

  /* The cost contract of the static parts: the blobs are painted once (their
     drift was invisible but made every frame a full-screen redraw) and there
     is no blend-mode grain over the animated layer. */
  const still = await page.evaluate(() => {
    const blobs = [...document.querySelectorAll(".ice-blob")].map((blob) => {
      const style = getComputedStyle(blob);
      return { animation: style.animationName, willChange: style.willChange };
    });
    const blended = [...document.querySelectorAll(".ice-scene, .ice-scene *")].filter(
      (el) => getComputedStyle(el).mixBlendMode !== "normal",
    ).length;
    return { blobs, blended, grain: document.querySelector(".ice-grain") !== null };
  });
  check(
    "blobs: static, painted once (no drift, no own layer)",
    still.blobs.length === 4 && still.blobs.every((blob) => blob.animation === "none" && blob.willChange === "auto"),
    JSON.stringify(still.blobs),
  );
  check("scene: no blend-mode grain over the animated layer", !still.grain && still.blended === 0, JSON.stringify(still));

  const layoutBefore = await page.evaluate(() => ({ width: document.documentElement.scrollWidth, height: document.documentElement.scrollHeight }));
  await page.waitForTimeout(1400);
  const layoutAfter = await page.evaluate(() => ({ width: document.documentElement.scrollWidth, height: document.documentElement.scrollHeight }));
  check("layout: no shift or scrollbar change while rising", layoutBefore.width === layoutAfter.width && layoutBefore.height === layoutAfter.height && layoutAfter.width <= 1280 + 1, JSON.stringify({ layoutBefore, layoutAfter }));

  const hit = await page.evaluate(() => {
    const point = document.elementFromPoint(window.innerWidth / 2, 6);
    return { sceneHit: point?.closest?.(".ice-scene") !== null, tag: point?.tagName ?? "" };
  });
  check("stacking: the scene never sits in front of the chrome", !hit.sceneHit, hit.tag);
  await context.close();
}

/* 1b. Aero's bubbles ride the same band ------------------------------- */
for (const [width, height] of [[1280, 900], [390, 844]]) {
  const { context, page } = await makePage(browser, { width, height, deviceScaleFactor: 1 });
  await seed(page, { decks: [DECK], theme: "aero" });
  await page.goto(BASE, { waitUntil: "networkidle" });
  await page.waitForTimeout(1000);
  const band = await page.evaluate(() => {
    const rect = document.querySelector(".ice-floats").getBoundingClientRect();
    return { top: rect.top, bottom: window.innerHeight - rect.bottom, left: rect.left };
  });
  check(
    `aero ${width}px: the band clears the chrome`,
    band.top === 68 && band.bottom === (width >= 640 ? 151 : 172) && band.left === (width >= 1024 ? 268 : 0),
    JSON.stringify(band),
  );
  const swept = await sweep(page, ".ice-bubble, .ice-orb");
  check(
    `aero ${width}px: a visible bubble never touches the band's edges`,
    swept.floats >= 20 && swept.samples > 300 && swept.misses.length === 0,
    swept.misses.slice(0, 3).join(" | ") || `${swept.floats} floats, ${swept.samples} visible frames`,
  );
  await context.close();
}

/* 2. per-breakpoint counts + phone pacing ----------------------------- */
{
  const counts = {};
  for (const width of [1280, 768, 390, 360]) {
    const { context, page } = await makePage(browser, { width, height: 800, deviceScaleFactor: 1 });
    await seed(page, { decks: [DECK] });
    await page.goto(BASE, { waitUntil: "networkidle" });
    await page.waitForTimeout(900);
    const info = await page.evaluate(() =>
      [...document.querySelectorAll(".ice-orb")]
        .filter((orb) => getComputedStyle(orb).display !== "none")
        .map((orb) => ({ duration: parseFloat(getComputedStyle(orb).animationDuration), delay: getComputedStyle(orb).animationDelay })),
    );
    counts[width] = info;
    check(`${width}px: no horizontal overflow`, await page.evaluate(() => document.documentElement.scrollWidth <= window.innerWidth + 1));
    await context.close();
  }
  check("desktop keeps 5 orbs", counts[1280].length === 5, String(counts[1280].length));
  check("tablet keeps 3 orbs", counts[768].length === 3, String(counts[768].length));
  check("phone keeps 2 orbs (fewer than before is not allowed)", counts[390].length === 2 && counts[360].length === 2, `${counts[390].length}/${counts[360].length}`);
  check("phone pacing is slower than desktop", counts[390][0].duration > counts[1280][0].duration && counts[390][1].duration > counts[1280][1].duration, `${counts[1280][0].duration}s → ${counts[390][0].duration}s`);
  check("all phone passes stay in 30-70s", counts[390].every((orb) => orb.duration >= 30 && orb.duration <= 70), counts[390].map((orb) => orb.duration).join(","));
  check("all phone delays negative", counts[390].every((orb) => orb.delay.startsWith("-")));
}

/* 3. reduced motion: static and visible ------------------------------- */
{
  const { context, page } = await makePage(browser, { reducedMotion: "reduce" });
  await seed(page, { decks: [DECK] });
  await page.goto(BASE, { waitUntil: "networkidle" });
  await page.waitForTimeout(900);
  const state = await page.evaluate(() => {
    const orb = document.querySelector(".ice-orb-1");
    const style = getComputedStyle(orb);
    const rect = orb.getBoundingClientRect();
    const floats = document.querySelector(".ice-floats").getBoundingClientRect();
    return {
      animation: style.animationName,
      willChange: style.willChange,
      opacity: Number(style.opacity),
      top: rect.top,
      left: rect.left,
      floats: { top: floats.top, bottom: floats.bottom, viewport: window.innerHeight },
    };
  });
  check(
    "reduced motion: the floats cover the whole scene again (parked orbs keep their spots)",
    state.floats.top === 0 && state.floats.bottom === state.floats.viewport,
    JSON.stringify(state.floats),
  );
  check("reduced motion: rise removed, layer released", state.animation === "none" && state.willChange === "auto", JSON.stringify(state));
  check("reduced motion: orb visible and faded in at a static spot", state.opacity > 0.08 && state.top > 0 && state.top < 900, JSON.stringify(state));
  await page.waitForTimeout(1100);
  const after = await page.evaluate(() => {
    const rect = document.querySelector(".ice-orb-1").getBoundingClientRect();
    return { top: rect.top, left: rect.left };
  });
  check("reduced motion: no movement over a second", Math.abs(after.top - state.top) < 1 && Math.abs(after.left - state.left) < 1, `${state.top.toFixed(1)} → ${after.top.toFixed(1)}`);
  await context.close();
}

/* 4. tab hidden, window blurred, dialog open: everything parks -------- */
{
  const { context, page } = await makePage(browser);
  await seed(page, { decks: [DECK] });
  await page.goto(BASE, { waitUntil: "networkidle" });
  await page.waitForTimeout(900);
  await page.evaluate(() => {
    Object.defineProperty(document, "hidden", { configurable: true, get: () => true });
    document.dispatchEvent(new Event("visibilitychange"));
  });
  await page.waitForTimeout(200);
  const paused = await page.evaluate(() => ({
    scene: document.querySelector(".ice-scene").classList.contains("ice-paused"),
    orb: getComputedStyle(document.querySelector(".ice-orb-1")).animationPlayState,
    transform: getComputedStyle(document.querySelector(".ice-orb-1")).transform,
    top: document.querySelector(".ice-orb-1").getBoundingClientRect().top,
  }));
  check("tab hidden: scene class + orb parked", paused.scene && paused.orb === "paused", JSON.stringify(paused));
  check("tab hidden: parked orb keeps its frame (no jump)", paused.transform !== "none", paused.transform);
  await page.waitForTimeout(500);
  const held = await page.evaluate(() => document.querySelector(".ice-orb-1").getBoundingClientRect().top);
  check("tab hidden: parked orb does not move", Math.abs(held - paused.top) < 1, `${paused.top.toFixed(1)} → ${held.toFixed(1)}`);
  await page.evaluate(() => {
    Object.defineProperty(document, "hidden", { configurable: true, get: () => false });
    document.dispatchEvent(new Event("visibilitychange"));
  });
  await page.waitForTimeout(200);
  const running = await page.evaluate(() => ({
    scene: document.querySelector(".ice-scene").classList.contains("ice-paused"),
    orb: getComputedStyle(document.querySelector(".ice-orb-1")).animationPlayState,
  }));
  check("tab visible again: rise resumes", !running.scene && running.orb === "running", JSON.stringify(running));

  /* A visible window without focus (another app in front, the browser on a
     second screen) parks too, and focus brings it back. */
  const focus = await page.evaluate(async () => {
    const frame = () => new Promise((resolve) => setTimeout(resolve, 150));
    const read = () => ({
      scene: document.querySelector(".ice-scene").classList.contains("ice-paused"),
      orb: getComputedStyle(document.querySelector(".ice-orb-1")).animationPlayState,
    });
    document.hasFocus = () => false;
    window.dispatchEvent(new Event("blur"));
    await frame();
    const blurred = read();
    document.hasFocus = () => true;
    window.dispatchEvent(new Event("focus"));
    await frame();
    return { blurred, focused: read() };
  });
  check("window blurred: the scene parks", focus.blurred.scene && focus.blurred.orb === "paused", JSON.stringify(focus.blurred));
  check("window focused again: the rise resumes", !focus.focused.scene && focus.focused.orb === "running", JSON.stringify(focus.focused));

  /* A dialog or sheet: its scrim (and the sheet's glass) blur whatever is
     behind them, so the scene holds still while one is open. */
  const scrim = await page.evaluate(async () => {
    const frame = () => new Promise((resolve) => setTimeout(resolve, 100));
    const overlay = document.createElement("div");
    overlay.className = "scene-pause";
    document.body.append(overlay);
    await frame();
    const open = getComputedStyle(document.querySelector(".ice-orb-1")).animationPlayState;
    overlay.remove();
    await frame();
    return { open, closed: getComputedStyle(document.querySelector(".ice-orb-1")).animationPlayState };
  });
  check("dialog scrim: the scene parks while it is open, resumes after", scrim.open === "paused" && scrim.closed === "running", JSON.stringify(scrim));
  await context.close();
}

/* 5. glass that sits still never blurs -------------------------------- */
{
  /* The study feed: only its floating chrome (header + pager pills, which
     the slides scroll under) keeps a backdrop blur. */
  const { context, page } = await makePage(browser, { width: 1280, height: 900, deviceScaleFactor: 1 });
  await seed(page, { decks: [DECK] });
  await page.goto(`${BASE}/deck/${DECK.id}`, { waitUntil: "networkidle" });
  await page.waitForTimeout(1200);
  const blurred = await page.evaluate(() =>
    [...document.querySelectorAll("body *")]
      .filter((el) => {
        const style = getComputedStyle(el);
        const filter = style.backdropFilter || style.webkitBackdropFilter;
        return filter && filter !== "none" && style.display !== "none" && el.getClientRects().length > 0;
      })
      .map((el) => String(el.className).split(" ")[0]),
  );
  check(
    "study feed: only the floating chrome blurs (no blur on tiles, chips or hints)",
    blurred.length > 0 && blurred.every((name) => name === "study-chrome"),
    blurred.join(", "),
  );
  await context.close();

  /* Aero desktop: under the opaque bake a live blur never shows, so the chat
     chrome carries none; touch drops the bake and keeps the blur. */
  for (const touch of [false, true]) {
    const aero = await makePage(browser, touch ? { width: 390, height: 844, isMobile: true, hasTouch: true } : { width: 1280, height: 900, deviceScaleFactor: 1 });
    await seed(aero.page, { decks: [DECK], theme: "aero" });
    await aero.page.goto(`${BASE}/chat`, { waitUntil: "networkidle" });
    await aero.page.waitForTimeout(1000);
    const chrome = await aero.page.evaluate(() =>
      [".chat-header", ".chat-composer-band"].map((selector) => {
        const style = getComputedStyle(document.querySelector(selector));
        return { filter: style.backdropFilter || style.webkitBackdropFilter, bake: style.backgroundImage.includes("background-blur") };
      }),
    );
    check(
      touch ? "aero touch: the chat chrome keeps its live blur (no bake)" : "aero desktop: the baked chat chrome drops the hidden live blur",
      touch
        ? chrome.every((panel) => !panel.bake && panel.filter.includes("blur"))
        : chrome.every((panel) => panel.bake && panel.filter === "none"),
      JSON.stringify(chrome),
    );
    await aero.context.close();
  }
}

await browser.close();
finish();