From 600053c63e69dfac83a76720115bae63d38915a0 Mon Sep 17 00:00:00 2001
From: Senko-san <senko@Senko-sans-Mac-mini.local>
Date: Fri, 12 Jun 2026 15:04:30 +0300
Subject: [PATCH] feat: fix lil stuff

---
 src/components/slider/index.tsx     |   6 -
 src/components/tabs/index.tsx       |  80 +++++++--
 src/components/text-field/index.tsx | 267 +---------------------------
 src/stories/Slider.stories.tsx      |   5 -
 src/stories/Tabs.stories.tsx        |  25 +++
 src/styles/components.css           | 201 +++++++--------------
 6 files changed, 163 insertions(+), 421 deletions(-)

diff --git a/src/components/slider/index.tsx b/src/components/slider/index.tsx
index d8b5a91..2532152 100644
--- a/src/components/slider/index.tsx
+++ b/src/components/slider/index.tsx
@@ -5,8 +5,6 @@ type Mark = { value: number; label?: string };
 type MarksProp = boolean | Array<number | Mark>;
 type NotchPlacement = 'top' | 'bottom' | 'both' | 'none';
 
-type KnobStyle = 'square' | 'round';
-
 type SliderProps = Omit<ComponentPropsWithoutRef<typeof RSlider.Root>, 'className'> & {
   /**
    * Step marks.
@@ -20,8 +18,6 @@ type SliderProps = Omit<ComponentPropsWithoutRef<typeof RSlider.Root>, 'classNam
    * (labels still render when provided). No effect without `marks`.
    */
   notches?: NotchPlacement;
-  /** Thumb shape. `'square'` (default) has a small border-radius; `'round'` is a full circle. */
-  knobStyle?: KnobStyle;
   /**
    * Enable step-glide animation. Defaults to `true` when `marks` is set, `false` otherwise.
    * Explicitly setting this always overrides the default.
@@ -77,7 +73,6 @@ const NotchLayer = ({
 export const Slider = ({
   marks,
   notches = 'bottom',
-  knobStyle = 'square',
   animated,
   min = 0,
   max = 100,
@@ -94,7 +89,6 @@ export const Slider = ({
 
   const cls = [
     'mta-slider',
-    `mta-slider--knob-${knobStyle}`,
     isAnimated && 'mta-slider--animated',
     hasMarks && 'mta-slider--has-marks',
     hasLabels && 'mta-slider--has-labels',
diff --git a/src/components/tabs/index.tsx b/src/components/tabs/index.tsx
index c0bf826..1c8e6a0 100644
--- a/src/components/tabs/index.tsx
+++ b/src/components/tabs/index.tsx
@@ -1,4 +1,4 @@
-import { type ComponentPropsWithoutRef } from 'react';
+import { type ComponentPropsWithoutRef, useEffect, useRef } from 'react';
 import { Tabs as RTabs } from 'radix-ui';
 import { cx } from '../utils';
 
@@ -6,23 +6,69 @@ export const Tabs = RTabs.Root;
 
 export const TabsList = ({
   items,
+  variant = 'primary',
   className,
   ...props
-}: { items: Array<{ value: string; label: string }> } & Omit<
-  ComponentPropsWithoutRef<typeof RTabs.List>,
-  'children'
->) => (
-  <RTabs.List className={cx('mta-tabs', className)} {...props}>
-    {items.map((it) => (
-      <RTabs.Trigger
-        key={it.value}
-        value={it.value}
-        className="mta-tabs__trigger"
-      >
-        {it.label}
-      </RTabs.Trigger>
-    ))}
-  </RTabs.List>
-);
+}: {
+  items: Array<{ value: string; label: string }>;
+  /** Visual style. `'primary'` (default) is the segmented pill track; `'secondary'` is the underline style. */
+  variant?: 'primary' | 'secondary';
+} & Omit<ComponentPropsWithoutRef<typeof RTabs.List>, 'children'>) => {
+  const listRef = useRef<HTMLDivElement>(null);
+  const thumbRef = useRef<HTMLSpanElement>(null);
+  const initialized = useRef(false);
+
+  useEffect(() => {
+    const list = listRef.current;
+    const thumb = thumbRef.current;
+    if (!list || !thumb) return;
+
+    const update = () => {
+      const active = list.querySelector<HTMLElement>('[role="tab"][data-state="active"]');
+      if (!active) return;
+
+      if (!initialized.current) {
+        thumb.style.transition = 'none';
+      }
+      thumb.style.transform = `translateX(${active.offsetLeft}px)`;
+      thumb.style.width = `${active.offsetWidth}px`;
+      if (!initialized.current) {
+        thumb.getBoundingClientRect();
+        thumb.style.transition = '';
+        initialized.current = true;
+      }
+    };
+
+    update();
+
+    const attrObserver = new MutationObserver(update);
+    list.querySelectorAll('[role="tab"]').forEach((tab) =>
+      attrObserver.observe(tab, { attributes: true, attributeFilter: ['data-state'] }),
+    );
+
+    const resizeObserver = new ResizeObserver(update);
+    resizeObserver.observe(list);
+
+    return () => {
+      attrObserver.disconnect();
+      resizeObserver.disconnect();
+    };
+  }, [variant, items]);
+
+  return (
+    <RTabs.List ref={listRef} className={cx('mta-tabs', `mta-tabs--${variant}`, className)} {...props}>
+      <span ref={thumbRef} className="mta-tabs__thumb" aria-hidden />
+      {items.map((it) => (
+        <RTabs.Trigger
+          key={it.value}
+          value={it.value}
+          className="mta-tabs__trigger"
+        >
+          {it.label}
+        </RTabs.Trigger>
+      ))}
+    </RTabs.List>
+  );
+};
 
 export const TabsContent = RTabs.Content;
diff --git a/src/components/text-field/index.tsx b/src/components/text-field/index.tsx
index 3f3bd77..7fe08cd 100644
--- a/src/components/text-field/index.tsx
+++ b/src/components/text-field/index.tsx
@@ -1,269 +1,20 @@
-import {
-  forwardRef,
-  useCallback,
-  useId,
-  useLayoutEffect,
-  useRef,
-  useState,
-  type ComponentPropsWithoutRef,
-  type ReactNode,
-  type Ref,
-} from 'react';
+import { forwardRef, type ComponentPropsWithoutRef, type ReactNode } from 'react';
 import { cx } from '../utils';
 
-/* ------------------------------------------------------------------ *
- * Typing animation (osu!-lazer style)
- *
- * Native inputs draw their own text, so individual letters can't be
- * animated. Instead the real field renders transparent (caret stays
- * visible) and a mirrored per-character <span> overlay sits behind it:
- * newly typed letters rise + fade in, erased letters fall + fade out.
- * ------------------------------------------------------------------ */
-
-type FieldElement = HTMLInputElement | HTMLTextAreaElement;
-
-interface CharEntry {
-  id: number;
-  char: string;
-  leaving: boolean;
-  x?: number;
-  y?: number;
-}
-
-/** Longest-common-subsequence match so unchanged letters keep their id
- *  (and thus don't replay the appear animation on every keystroke). */
-function diffChars(prev: ReadonlyArray<{ id: number; char: string }>, next: string) {
-  const n = prev.length;
-  const m = next.length;
-  const dp: number[][] = Array.from({ length: n + 1 }, () => new Array(m + 1).fill(0));
-  for (let i = n - 1; i >= 0; i--) {
-    for (let j = m - 1; j >= 0; j--) {
-      dp[i][j] =
-        prev[i].char === next[j]
-          ? dp[i + 1][j + 1] + 1
-          : Math.max(dp[i + 1][j], dp[i][j + 1]);
-    }
-  }
-  const reusedId: Array<number | null> = new Array(m).fill(null);
-  const keptPrev = new Array(n).fill(false);
-  let i = 0;
-  let j = 0;
-  while (i < n && j < m) {
-    if (prev[i].char === next[j]) {
-      reusedId[j] = prev[i].id;
-      keptPrev[i] = true;
-      i++;
-      j++;
-    } else if (dp[i + 1][j] >= dp[i][j + 1]) {
-      i++;
-    } else {
-      j++;
-    }
-  }
-  return { reusedId, keptPrev };
-}
-
-function useFieldAnimation(
-  multiline: boolean,
-  externalRef: Ref<FieldElement>,
-  controlledValue: ComponentPropsWithoutRef<'input'>['value'],
-  initial: ComponentPropsWithoutRef<'input'>['defaultValue'],
-) {
-  const innerRef = useRef<FieldElement | null>(null);
-  const overlayRef = useRef<HTMLDivElement | null>(null);
-  const spanRefs = useRef<Map<number, HTMLSpanElement>>(new Map());
-  const present = useRef<Array<{ id: number; char: string }>>([]);
-  const nextId = useRef(0);
-  const idPrefix = useId();
-
-  const [text, setText] = useState(() => String(controlledValue ?? initial ?? ''));
-  const [entries, setEntries] = useState<CharEntry[]>([]);
-
-  const setRef = useCallback(
-    (node: FieldElement | null) => {
-      innerRef.current = node;
-      if (typeof externalRef === 'function') externalRef(node);
-      else if (externalRef) (externalRef as { current: FieldElement | null }).current = node;
-    },
-    [externalRef],
-  );
-
-  const syncScroll = useCallback(() => {
-    const el = innerRef.current;
-    const ov = overlayRef.current;
-    if (el && ov) ov.style.transform = `translate(${-el.scrollLeft}px, ${-el.scrollTop}px)`;
-  }, []);
-
-  // Reconcile the overlay whenever the text changes.
-  useLayoutEffect(() => {
-    const prev = present.current;
-    const { reusedId, keptPrev } = diffChars(prev, text);
-
-    const nextPresent: Array<{ id: number; char: string }> = [];
-    for (let k = 0; k < text.length; k++) {
-      const id = reusedId[k] ?? nextId.current++;
-      nextPresent.push({ id, char: text[k] });
-    }
-
-    // Letters that were removed fall away — pin them where they last sat.
-    const leaving: CharEntry[] = [];
-    for (let k = 0; k < prev.length; k++) {
-      if (keptPrev[k]) continue;
-      const el = spanRefs.current.get(prev[k].id);
-      if (el) {
-        leaving.push({
-          id: prev[k].id,
-          char: prev[k].char,
-          leaving: true,
-          x: el.offsetLeft,
-          y: el.offsetTop,
-        });
-      }
-    }
-
-    present.current = nextPresent;
-    setEntries((current) => [
-      ...nextPresent.map((e) => ({ ...e, leaving: false })),
-      ...current.filter((e) => e.leaving),
-      ...leaving,
-    ]);
-    syncScroll();
-  }, [text, syncScroll]);
-
-  // Stay in sync when used as a controlled component.
-  useLayoutEffect(() => {
-    if (controlledValue !== undefined) setText(String(controlledValue));
-  }, [controlledValue]);
-
-  const handleChange = useCallback((value: string) => setText(value), []);
-
-  const onLeaveEnd = useCallback((id: number) => {
-    spanRefs.current.delete(id);
-    setEntries((current) => current.filter((e) => e.id !== id));
-  }, []);
-
-  const overlay = (
-    <div
-      ref={overlayRef}
-      aria-hidden="true"
-      className={cx('mta-field-overlay', multiline && 'mta-field-overlay--multiline')}
-    >
-      {entries.map((e) =>
-        e.leaving ? (
-          <span
-            key={`${idPrefix}-${e.id}`}
-            className="mta-field-char mta-field-char--leaving"
-            style={{ left: e.x, top: e.y }}
-            onAnimationEnd={() => onLeaveEnd(e.id)}
-          >
-            {e.char}
-          </span>
-        ) : (
-          <span
-            key={`${idPrefix}-${e.id}`}
-            ref={(node) => {
-              if (node) spanRefs.current.set(e.id, node);
-              else spanRefs.current.delete(e.id);
-            }}
-            className={cx('mta-field-char', !multiline && 'mta-field-char--composited')}
-          >
-            {e.char}
-          </span>
-        ),
-      )}
-    </div>
-  );
-
-  return { setRef, overlay, handleChange, syncScroll };
-}
-
-type TextFieldProps = ComponentPropsWithoutRef<'input'> & { animated?: boolean };
-type TextAreaProps = ComponentPropsWithoutRef<'textarea'> & { animated?: boolean };
+type TextFieldProps = ComponentPropsWithoutRef<'input'>;
+type TextAreaProps = ComponentPropsWithoutRef<'textarea'>;
 
 export const TextField = forwardRef<HTMLInputElement, TextFieldProps>(
-  ({ className, style, onChange, onScroll, animated = true, ...props }, ref) => {
-    const { setRef, overlay, handleChange, syncScroll } = useFieldAnimation(
-      false,
-      ref,
-      props.value,
-      props.defaultValue,
-    );
-    if (!animated) {
-      return (
-        <input
-          ref={ref}
-          className={cx('mta-field', className)}
-          style={style}
-          onChange={onChange}
-          onScroll={onScroll}
-          {...props}
-        />
-      );
-    }
-    return (
-      <div className={cx('mta-field-wrap', className)} style={style}>
-        <input
-          ref={setRef}
-          className="mta-field mta-field--animated"
-          onChange={(e) => {
-            handleChange(e.currentTarget.value);
-            onChange?.(e);
-          }}
-          onScroll={(e) => {
-            syncScroll();
-            onScroll?.(e);
-          }}
-          {...props}
-        />
-        {overlay}
-      </div>
-    );
-  },
+  ({ className, ...props }, ref) => (
+    <input ref={ref} className={cx('mta-field', className)} {...props} />
+  ),
 );
 TextField.displayName = 'TextField';
 
 export const TextArea = forwardRef<HTMLTextAreaElement, TextAreaProps>(
-  ({ className, style, onChange, onScroll, animated = true, ...props }, ref) => {
-    const { setRef, overlay, handleChange, syncScroll } = useFieldAnimation(
-      true,
-      ref,
-      props.value,
-      props.defaultValue,
-    );
-    if (!animated) {
-      return (
-        <textarea
-          ref={ref}
-          className={cx('mta-field', className)}
-          style={style}
-          onChange={onChange}
-          onScroll={onScroll}
-          {...props}
-        />
-      );
-    }
-    return (
-      <div
-        className={cx('mta-field-wrap', 'mta-field-wrap--multiline', className)}
-        style={style}
-      >
-        <textarea
-          ref={setRef}
-          className="mta-field mta-field--animated"
-          onChange={(e) => {
-            handleChange(e.currentTarget.value);
-            onChange?.(e);
-          }}
-          onScroll={(e) => {
-            syncScroll();
-            onScroll?.(e);
-          }}
-          {...props}
-        />
-        {overlay}
-      </div>
-    );
-  },
+  ({ className, ...props }, ref) => (
+    <textarea ref={ref} className={cx('mta-field', className)} {...props} />
+  ),
 );
 TextArea.displayName = 'TextArea';
 
diff --git a/src/stories/Slider.stories.tsx b/src/stories/Slider.stories.tsx
index 03719dc..a39902f 100644
--- a/src/stories/Slider.stories.tsx
+++ b/src/stories/Slider.stories.tsx
@@ -28,11 +28,6 @@ const meta = {
       options: ['top', 'bottom', 'both', 'none'],
       description: 'Notch tick placement relative to the track (labels still render when `none`).',
     },
-    knobStyle: {
-      control: 'inline-radio',
-      options: ['square', 'round'],
-      description: 'Knob shape: `square` (default) or `round`.',
-    },
     className: { control: 'text' },
   },
   decorators: [(Story) => <div style={{ width: 280 }}><Story /></div>],
diff --git a/src/stories/Tabs.stories.tsx b/src/stories/Tabs.stories.tsx
index efab539..9b17a67 100644
--- a/src/stories/Tabs.stories.tsx
+++ b/src/stories/Tabs.stories.tsx
@@ -45,3 +45,28 @@ export const Playground: Story = {
     </Tabs>
   ),
 };
+
+/** `variant="secondary"` swaps the segmented pill track for an underline. */
+export const Secondary: Story = {
+  render: () => (
+    <Tabs defaultValue="overview" style={{ width: 420 }}>
+      <TabsList
+        variant="secondary"
+        items={[
+          { value: 'overview', label: 'Overview' },
+          { value: 'activity', label: 'Activity' },
+          { value: 'settings', label: 'Settings' },
+        ]}
+      />
+      <TabsContent value="overview" style={{ paddingTop: 16 }} className="mta-body">
+        Project at a glance.
+      </TabsContent>
+      <TabsContent value="activity" style={{ paddingTop: 16 }} className="mta-body">
+        Recent activity feed.
+      </TabsContent>
+      <TabsContent value="settings" style={{ paddingTop: 16 }} className="mta-body">
+        Preferences and configuration.
+      </TabsContent>
+    </Tabs>
+  ),
+};
diff --git a/src/styles/components.css b/src/styles/components.css
index d04a825..c076b95 100644
--- a/src/styles/components.css
+++ b/src/styles/components.css
@@ -195,117 +195,6 @@ textarea.mta-field {
   padding-left: 34px;
 }
 
-/* ---------- TYPING ANIMATION (osu!-lazer style char in/out) ---------- */
-/* The real field renders transparent over a mirrored per-letter overlay. */
-.mta-field-wrap {
-  position: relative;
-  width: 100%;
-}
-.mta-search .mta-field-wrap {
-  width: 100%;
-}
-.mta-field--animated {
-  color: transparent;
-  caret-color: var(--color-text-primary);
-}
-.mta-field--animated::placeholder {
-  color: var(--color-text-muted);
-}
-
-.mta-field-overlay {
-  position: absolute;
-  inset: 0;
-  overflow: hidden;
-  pointer-events: none;
-  /* transparent border mirrors the field's 1px border so content aligns */
-  border: 1px solid transparent;
-  padding: var(--field-pad-y) var(--field-pad-x);
-  font-family: var(--mta-font-sans);
-  font-size: var(--ctl-font);
-  line-height: normal;
-  color: var(--color-text-primary);
-  white-space: pre;
-  text-align: left;
-  will-change: transform;
-}
-.mta-field-overlay--multiline {
-  white-space: pre-wrap;
-  overflow-wrap: break-word;
-  line-height: 1.5;
-}
-.mta-search .mta-field-overlay {
-  padding-left: 34px;
-}
-
-.mta-field-char {
-  /* inline (not inline-block) so the overlay wraps exactly like the field;
-     inherit white-space so multiline (pre-wrap) wraps while input (pre) won't.
-     'pre' on the span itself would suppress wrapping at its boundaries.
-     Multiline keeps this inline path: inline boxes ignore transform, so the
-     rise eases `top` (a layout property — acceptable here, textarea wraps
-     instead of scrolling so there's no per-keystroke scroll-sync thrash). */
-  position: relative;
-  white-space: inherit;
-  animation: mta-char-in var(--dur-base) var(--ease-snap) both;
-}
-/* Single-line never wraps, so chars can be inline-block and animate
-   `transform` (compositor-only) instead of `top` (relayout every frame).
-   The single-line field scrolls horizontally and syncs the overlay each
-   keystroke, so the layout-triggering `top` path janked there — this doesn't. */
-.mta-field-char--composited {
-  display: inline-block;
-  will-change: transform, opacity;
-  animation-name: mta-char-in-rise;
-}
-.mta-field-char--leaving {
-  display: inline-block;
-  position: absolute;
-  white-space: pre;
-  animation: mta-char-out var(--dur-base) var(--ease-out) forwards;
-}
-
-/* inline elements ignore transform, so the rise uses top instead */
-@keyframes mta-char-in {
-  from {
-    opacity: 0;
-    top: -0.32em;
-  }
-  to {
-    opacity: 1;
-    top: 0;
-  }
-}
-/* inline-block (single-line) variant — composited transform, no relayout */
-@keyframes mta-char-in-rise {
-  from {
-    opacity: 0;
-    transform: translateY(-0.32em);
-  }
-  to {
-    opacity: 1;
-    transform: none;
-  }
-}
-@keyframes mta-char-out {
-  from {
-    opacity: 1;
-    transform: translateY(0);
-  }
-  to {
-    opacity: 0;
-    transform: translateY(0.7em) scale(0.9);
-  }
-}
-
-@media (prefers-reduced-motion: reduce) {
-  .mta-field-char {
-    animation: none;
-  }
-  .mta-field-char--leaving {
-    animation: mta-char-out 1ms linear forwards;
-  }
-}
-
 /* ---------- SELECT (Radix Select) ---------- */
 .mta-select {
   font-family: var(--mta-font-sans);
@@ -595,7 +484,6 @@ textarea.mta-field {
 /* ---------- SLIDER ---------- */
 .mta-slider {
   --ms-thumb: 20px;
-  --ms-thumb-w: var(--ms-thumb);
   position: relative;
   display: flex;
   align-items: center;
@@ -626,9 +514,9 @@ textarea.mta-field {
 }
 .mta-slider__thumb {
   display: block;
-  width: var(--ms-thumb-w);
+  width: var(--ms-thumb);
   height: var(--ms-thumb);
-  border-radius: 4px;
+  border-radius: 50%;
   background: #fff;
   border: 1.5px solid var(--color-border-strong);
   box-shadow: var(--mta-shadow-sm);
@@ -647,13 +535,6 @@ textarea.mta-field {
     transition: none;
   }
 }
-.mta-slider--knob-square .mta-slider__thumb {
-  --ms-thumb-w: 14px;
-}
-.mta-slider--knob-round .mta-slider__thumb {
-  --ms-thumb-w: var(--ms-thumb);
-  border-radius: 50%;
-}
 .mta-slider__thumb:focus-visible {
   border-color: var(--color-border-focus);
   box-shadow: var(--mta-shadow-sm), var(--focus-ring);
@@ -924,37 +805,87 @@ textarea.mta-field {
 
 /* ---------- TABS (Radix Tabs) ---------- */
 .mta-tabs {
-  display: flex;
+  display: inline-flex;
+  align-items: center;
   gap: 2px;
-  border-bottom: 1px solid var(--color-border);
 }
 .mta-tabs__trigger {
   font-family: var(--mta-font-sans);
   font-size: var(--mta-font-size-sm);
-  font-weight: var(--mta-font-weight-semibold);
-  color: var(--color-text-muted);
   background: transparent;
   border: none;
-  padding: 9px 14px;
   cursor: pointer;
   position: relative;
-  transition: color var(--dur-quick);
+  transition:
+    color var(--dur-quick),
+    background var(--dur-quick),
+    box-shadow var(--dur-quick);
 }
-.mta-tabs__trigger:hover {
+
+/* Primary (default) — pill track with sliding thumb */
+.mta-tabs--primary {
+  position: relative;
+  padding: 4px;
+  background: var(--color-bg-card);
+  border-radius: var(--r-pill);
+  box-shadow: var(--mta-shadow-sm);
+}
+.mta-tabs__thumb {
+  position: absolute;
+  top: 4px;
+  left: 0;
+  height: calc(100% - 8px);
+  background: var(--color-accent);
+  border-radius: var(--r-pill);
+  pointer-events: none;
+  transition:
+    transform var(--dur-quick) var(--ease-out),
+    width var(--dur-quick) var(--ease-out);
+  will-change: transform, width;
+}
+.mta-tabs--primary .mta-tabs__trigger {
+  position: relative;
+  z-index: 1;
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  height: 36px;
+  padding: 0 20px;
+  border-radius: var(--r-pill);
+  font-weight: var(--mta-font-weight-medium);
   color: var(--color-text-secondary);
 }
-.mta-tabs__trigger[data-state='active'] {
+.mta-tabs--primary .mta-tabs__trigger:hover {
   color: var(--color-text-primary);
 }
-.mta-tabs__trigger[data-state='active']::after {
-  content: '';
-  position: absolute;
-  left: 8px;
-  right: 8px;
+.mta-tabs--primary .mta-tabs__trigger[data-state='active'] {
+  color: var(--color-text-on-primary);
+}
+
+/* Secondary — underline with sliding indicator */
+.mta-tabs--secondary {
+  position: relative;
+  border-bottom: 1px solid var(--color-border);
+  border-radius: 0;
+}
+.mta-tabs--secondary .mta-tabs__thumb {
+  top: auto;
+  left: 0;
   bottom: -1px;
   height: 2px;
+  width: 0;
   border-radius: 2px;
-  background: var(--color-accent);
+}
+.mta-tabs--secondary .mta-tabs__trigger {
+  font-weight: var(--mta-font-weight-semibold);
+  color: var(--color-text-muted);
+  padding: 9px 14px;
+}
+.mta-tabs--secondary .mta-tabs__trigger:hover {
+  color: var(--color-text-secondary);
+}
+.mta-tabs--secondary .mta-tabs__trigger[data-state='active'] {
+  color: var(--color-text-primary);
 }
 
 /* ---------- PROGRESS (Radix Progress) ---------- */