import { useState } from "react";
import { NavLink, useLocation } from "react-router-dom";
import { useAuth } from "../auth/AuthContext";

const navItems = [
  { to: "/", label: "Dashboard", permission: null },
  {
    label: "Melodies",
    permission: "melodies",
    children: [
      { to: "/melodies", label: "Main Editor" },
      { to: "/melodies/archetypes", label: "Archetypes" },
      { to: "/melodies/settings", label: "Settings" },
      { to: "/melodies/composer", label: "Composer" },
    ],
  },
  { to: "/devices", label: "Devices", permission: "devices" },
  { to: "/users", label: "App Users", permission: "app_users" },
  {
    label: "MQTT",
    permission: "mqtt",
    children: [
      { to: "/mqtt", label: "Dashboard" },
      { to: "/mqtt/commands", label: "Commands" },
      { to: "/mqtt/logs", label: "Logs" },
    ],
  },
  { to: "/equipment/notes", label: "Issues and Notes", permission: "equipment" },
  {
    label: "Manufacturing",
    permission: "manufacturing",
    children: [
      { to: "/manufacturing", label: "Device Inventory" },
      { to: "/manufacturing/batch/new", label: "New Batch" },
      { to: "/firmware", label: "Firmware" },
    ],
  },
];

const linkClass = (isActive, locked) =>
  `block px-3 py-2 rounded-md text-sm transition-colors ${
    locked
      ? "opacity-40 cursor-not-allowed"
      : isActive
        ? "bg-[var(--accent)] text-[var(--bg-primary)] font-medium"
        : "text-[var(--text-secondary)] hover:bg-[var(--bg-card-hover)] hover:text-[var(--text-heading)]"
  }`;

export default function Sidebar() {
  const { hasPermission, hasRole } = useAuth();
  const location = useLocation();

  const canViewSection = (permission) => {
    if (!permission) return true;
    return hasPermission(permission, "view");
  };

  // Settings visible only to sysadmin and admin
  const canManageStaff = hasRole("sysadmin", "admin");

  return (
    <aside className="w-56 h-screen flex-shrink-0 p-4 border-r flex flex-col overflow-y-auto" style={{ backgroundColor: "var(--bg-sidebar)", borderColor: "var(--border-primary)" }}>
      <div className="mb-8 px-2">
        <img
          src="/logo-dark.png"
          alt="BellSystems"
          className="h-10 w-auto"
        />
      </div>
      <nav className="space-y-1 flex-1">
        {navItems.map((item) => {
          const hasAccess = canViewSection(item.permission);
          return item.children ? (
            <CollapsibleGroup
              key={item.label}
              label={item.label}
              children={item.children}
              currentPath={location.pathname}
              locked={!hasAccess}
            />
          ) : (
            <NavLink
              key={item.to}
              to={hasAccess ? item.to : "#"}
              end={item.to === "/"}
              className={({ isActive }) => linkClass(isActive && hasAccess, !hasAccess)}
              onClick={(e) => !hasAccess && e.preventDefault()}
            >
              <span className="flex items-center gap-2">
                {item.label}
                {!hasAccess && (
                  <svg className="w-3.5 h-3.5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M12 15v2m-6 4h12a2 2 0 002-2v-6a2 2 0 00-2-2H6a2 2 0 00-2 2v6a2 2 0 002 2zm10-10V7a4 4 0 00-8 0v4h8z" />
                  </svg>
                )}
              </span>
            </NavLink>
          );
        })}
      </nav>

      {/* Settings section at the bottom */}
      {canManageStaff && (
        <div className="mt-4 pt-4 border-t" style={{ borderColor: "var(--border-primary)" }}>
          <nav className="space-y-1">
            <CollapsibleGroup
              label="Settings"
              children={[
                { to: "/settings/staff", label: "Staff" },
              ]}
              currentPath={location.pathname}
            />
          </nav>
        </div>
      )}
    </aside>
  );
}

function CollapsibleGroup({ label, children, currentPath, locked = false }) {
  const isChildActive = children.some(
    (child) =>
      currentPath === child.to ||
      (child.to !== "/" && currentPath.startsWith(child.to + "/"))
  );
  const [open, setOpen] = useState(isChildActive);

  const shouldBeOpen = open || isChildActive;

  return (
    <div>
      <button
        type="button"
        onClick={() => !locked && setOpen(!shouldBeOpen)}
        className={`w-full flex items-center justify-between px-3 py-2 rounded-md text-sm transition-colors ${
          locked
            ? "opacity-40 cursor-not-allowed"
            : isChildActive
              ? "text-[var(--text-heading)]"
              : "text-[var(--text-secondary)] hover:bg-[var(--bg-card-hover)] hover:text-[var(--text-heading)]"
        }`}
      >
        <span className="flex items-center gap-2">
          {label}
          {locked && (
            <svg className="w-3.5 h-3.5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M12 15v2m-6 4h12a2 2 0 002-2v-6a2 2 0 00-2-2H6a2 2 0 00-2 2v6a2 2 0 002 2zm10-10V7a4 4 0 00-8 0v4h8z" />
            </svg>
          )}
        </span>
        {!locked && (
          <svg
            className={`w-4 h-4 transition-transform ${shouldBeOpen ? "rotate-90" : ""}`}
            fill="none"
            stroke="currentColor"
            viewBox="0 0 24 24"
          >
            <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 5l7 7-7 7" />
          </svg>
        )}
      </button>
      {!locked && shouldBeOpen && (
        <div className="ml-3 mt-1 space-y-1">
          {children.map((child) => (
            <NavLink
              key={child.to}
              to={child.to}
              end
              className={({ isActive }) =>
                `block pl-4 pr-3 py-1.5 rounded-md text-sm transition-colors ${
                  isActive
                    ? "bg-[var(--accent)] text-[var(--bg-primary)] font-medium"
                    : "text-[var(--text-muted)] hover:bg-[var(--bg-card-hover)] hover:text-[var(--text-heading)]"
                }`
              }
            >
              {child.label}
            </NavLink>
          ))}
        </div>
      )}
    </div>
  );
}