"use client";

import * as React from "react";
import { cn } from "@/lib/utils";

// ─── Types ────────────────────────────────────────────────────────────────────

export interface NavItem {
  id: string;
  label: string;
  href?: string;
  icon?: React.ReactNode;
  badge?: string | number;
  disabled?: boolean;
}

export interface NavGroup {
  id: string;
  title?: string;
  items: NavItem[];
}

export interface SideNavProps extends React.HTMLAttributes<HTMLElement> {
  /** 品牌名 */
  brandName?: string;
  /** 品牌图标 */
  brandIcon?: React.ReactNode;
  /** 导航分组 */
  groups: NavGroup[];
  /** 当前激活的导航项 id */
  activeId?: string;
  /** 导航项点击回调 */
  onNavClick?: (item: NavItem) => void;
}

// ─── NavItemRow ───────────────────────────────────────────────────────────────

const NavItemRow = React.memo(
  ({
    item,
    active,
    onClick,
  }: {
    item: NavItem;
    active: boolean;
    onClick?: () => void;
  }) => {
    return (
      <button
        type="button"
        disabled={item.disabled}
        onClick={onClick}
        className={cn(
          "group relative flex w-full items-center gap-3 rounded-lg py-2.5 px-4 text-sm font-medium transition-all duration-150",
          "focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-emerald-500 focus-visible:ring-offset-1",
          "disabled:pointer-events-none disabled:opacity-40",
          active
            ? "bg-emerald-50 text-emerald-600 font-semibold border-l-[3px] border-emerald-500"
            : "text-gray-600 hover:bg-gray-50 border-l-[3px] border-transparent"
        )}
      >
        {/* icon */}
        {item.icon && (
          <span
            className={cn(
              "flex h-5 w-5 shrink-0 items-center justify-center transition-colors duration-150",
              active ? "text-emerald-500" : "text-gray-400 group-hover:text-gray-600"
            )}
          >
            {item.icon}
          </span>
        )}

        {/* label */}
        <span className="flex-1 truncate text-left">{item.label}</span>

        {/* badge */}
        {item.badge !== undefined && (
          <span
            className={cn(
              "ml-auto flex h-5 min-w-5 items-center justify-center rounded-full px-1.5 text-[10px] font-bold",
              active
                ? "bg-emerald-500 text-white"
                : "bg-gray-200 text-gray-600"
            )}
          >
            {item.badge}
          </span>
        )}
      </button>
    );
  }
);
NavItemRow.displayName = "NavItemRow";

// ─── Main SideNav ─────────────────────────────────────────────────────────────

const SideNav = React.forwardRef<HTMLElement, SideNavProps>(
  (
    {
      className,
      brandName = "GEO Platform",
      brandIcon,
      groups,
      activeId,
      onNavClick,
      ...props
    },
    ref
  ) => {
    return (
      <nav
        ref={ref}
        className={cn(
          "flex flex-col h-full bg-white border-r border-gray-200 overflow-y-auto",
          "w-60",
          className
        )}
        {...props}
      >
        {/* ── Brand header ── */}
        <div className="flex items-center gap-3 px-5 py-5 border-b border-gray-200 pb-6 mb-4 shrink-0">
          {brandIcon && (
            <div className="flex h-8 w-8 shrink-0 items-center justify-center rounded-lg bg-emerald-500 text-white">
              {brandIcon}
            </div>
          )}
          {!brandIcon && (
            <div className="flex h-8 w-8 shrink-0 items-center justify-center rounded-lg bg-emerald-500 text-sm font-bold text-white">
              G
            </div>
          )}
          <span className="text-base font-bold text-gray-900 tracking-tight truncate">
            {brandName}
          </span>
        </div>

        {/* ── Nav groups ── */}
        <div className="flex-1 overflow-y-auto px-3 pb-3 space-y-6">
          {groups.map((group) => (
            <div key={group.id}>
              {group.title && (
                <p className="mb-2 px-4 text-xs font-semibold text-gray-400 uppercase tracking-wider">
                  {group.title}
                </p>
              )}
              <div className="space-y-0.5">
                {group.items.map((item) => (
                  <NavItemRow
                    key={item.id}
                    item={item}
                    active={item.id === activeId}
                    onClick={() => onNavClick?.(item)}
                  />
                ))}
              </div>
            </div>
          ))}
        </div>
      </nav>
    );
  }
);
SideNav.displayName = "SideNav";

export { SideNav };