Drawer

// Shared motion tokens. Easing curves mirror the CSS custom properties in
// globals.css; springs are the canonical physics used across components.
// Strong custom variants — defaults like `ease-in`/`ease-out` feel weak.

export const EASE_OUT = [0.16, 1, 0.3, 1] as const;
export const EASE_IN_OUT = [0.77, 0, 0.175, 1] as const;
export const EASE_DRAWER = [0.32, 0.72, 0, 1] as const;

/** CSS string form of EASE_OUT for inline style transitions. */
export const EASE_OUT_CSS = "cubic-bezier(0.16, 1, 0.3, 1)";

/** Press feedback on buttons and other tappable surfaces. */
export const SPRING_PRESS = {
  type: "spring",
  stiffness: 500,
  damping: 30,
  mass: 0.6,
} as const;

/** Content swaps — label/icon slots trading places inside a control. */
export const SPRING_SWAP = {
  type: "spring",
  stiffness: 460,
  damping: 30,
  mass: 0.55,
} as const;

/** Overlay panel entrances — modals and sheets summoned by pointer. */
export const SPRING_PANEL = {
  type: "spring",
  stiffness: 420,
  damping: 40,
  mass: 0.5,
} as const;

/** Shared-layout glides — pills, indicators and panels morphing between positions. */
export const SPRING_LAYOUT = {
  type: "spring",
  stiffness: 360,
  damping: 32,
  mass: 0.6,
} as const;

/** Cursor-follow physics for decorative mouse tracking (magnetic, tilt, dock). */
export const SPRING_MOUSE = {
  stiffness: 200,
  damping: 15,
  mass: 0.3,
} as const;

import { clsx, type ClassValue } from "clsx"
import { twMerge } from "tailwind-merge"

export function cn(...inputs: ClassValue[]) {
  return twMerge(clsx(inputs))
}

"use client";

import { AnimatePresence, motion, useReducedMotion } from "motion/react";
import { useEffect, type ReactNode } from "react";
import { EASE_OUT, SPRING_PANEL } from "@/lib/ease";
import { cn } from "@/lib/utils";

export interface DrawerProps {
  open: boolean;
  onOpenChange: (open: boolean) => void;
  side?: "left" | "right";
  children: ReactNode;
  /** Class for the panel surface. */
  className?: string;
  /** Class for the backdrop. */
  backdropClassName?: string;
  ariaLabel?: string;
  /** Close when the backdrop is clicked. Default true. */
  dismissable?: boolean;
}

export function Drawer({
  open,
  onOpenChange,
  side = "right",
  children,
  className,
  backdropClassName,
  ariaLabel,
  dismissable = true,
}: DrawerProps) {
  const reduce = useReducedMotion();

  useEffect(() => {
    if (!open) return;
    const onKey = (e: KeyboardEvent) => {
      if (e.key === "Escape") onOpenChange(false);
    };
    window.addEventListener("keydown", onKey);
    const prevOverflow = document.body.style.overflow;
    document.body.style.overflow = "hidden";
    return () => {
      window.removeEventListener("keydown", onKey);
      document.body.style.overflow = prevOverflow;
    };
  }, [open, onOpenChange]);

  const offscreen = side === "right" ? "100%" : "-100%";

  return (
    <AnimatePresence>
      {open ? (
        <div className="fixed inset-0 z-50">
          <motion.button
            type="button"
            aria-label="Close"
            tabIndex={dismissable ? 0 : -1}
            onClick={() => dismissable && onOpenChange(false)}
            initial={{ opacity: 0 }}
            animate={{ opacity: 1 }}
            exit={{ opacity: 0 }}
            transition={{ duration: 0.25, ease: EASE_OUT }}
            className={cn(
              "absolute inset-0 h-full w-full cursor-default bg-black/40 backdrop-blur-sm",
              backdropClassName,
            )}
          />
          <motion.aside
            role="dialog"
            aria-modal="true"
            aria-label={ariaLabel}
            initial={reduce ? { opacity: 0 } : { x: offscreen }}
            animate={reduce ? { opacity: 1 } : { x: 0 }}
            exit={reduce ? { opacity: 0 } : { x: offscreen }}
            transition={reduce ? { duration: 0.2, ease: EASE_OUT } : SPRING_PANEL}
            className={cn(
              "absolute inset-y-0 flex w-80 max-w-[85vw] flex-col bg-background shadow-2xl",
              side === "right"
                ? "right-0 border-l border-border"
                : "left-0 border-r border-border",
              className,
            )}
          >
            {children}
          </motion.aside>
        </div>
      ) : null}
    </AnimatePresence>
  );
}