"use client";

import { useState } from "react";
import Link from "next/link";
import { usePathname, useRouter } from "next/navigation";
import {
  Home,
  Compass,
  Plus,
  Bell,
  User,
  ChevronDown,
} from "lucide-react";
import { PostTypeSheet } from "@/components/post-creation/PostTypeSheet";
import {
  DropdownMenu,
  DropdownMenuContent,
  DropdownMenuItem,
  DropdownMenuSeparator,
  DropdownMenuTrigger,
} from "@/components/ui/dropdown-menu";
import { Avatar, AvatarFallback, AvatarImage } from "@/components/ui/avatar";
import { Badge } from "@/components/ui/badge";
import { useActivePet } from "@/context/ActivePetContext";
import { getAvatarUrl } from "@/lib/avatar-url";

type Pet = {
  id: string;
  name: string;
  avatarKey: string | null;
  species: { name: string };
};

type MobileNavProps = {
  pets: Pet[];
};

/**
 * Mobile bottom tab bar — visible below lg: breakpoint.
 *
 * UI-SPEC: Navigation (App Shell) — Mobile
 * - Fixed bottom bar (h-16) with bg-card border-top
 * - 5 tabs: Home, Explore (placeholder), Post (center, orange-500), Notifications (placeholder), Profile
 * - Top active pet switcher dropdown above the tab bar
 *
 * Explore and Notifications are placeholder tabs (aria-disabled) in Phase 1.
 * Post tab (center) links to /pets in Phase 1 — full post creation in Phase 2.
 *
 * Deviation notes:
 * - shadcn base-nova uses @base-ui/react/menu which does not support asChild on
 *   DropdownMenuTrigger or DropdownMenuItem. Using onClick+useRouter for navigation items.
 */
export function MobileNav({ pets }: MobileNavProps) {
  const pathname = usePathname();
  const router = useRouter();
  const { activePetId, setActivePet } = useActivePet();

  const activePet = pets.find((p) => p.id === activePetId) ?? pets[0];
  const [postTypeSheetOpen, setPostTypeSheetOpen] = useState(false);

  // D-05: Home → /feed; also highlight when on / (which redirects to /feed)
  const isHomePage = pathname === "/feed" || pathname === "/";
  const isPetsPage = pathname.startsWith("/pets");

  return (
    <div className="lg:hidden fixed bottom-0 left-0 right-0 z-50">
      {/* Active pet switcher bar — shown above tab bar on mobile */}
      {activePet && (
        <div className="bg-background border-t border px-4 py-2">
          <DropdownMenu>
            <DropdownMenuTrigger
              className="flex items-center gap-2 text-sm cursor-pointer"
              aria-label="Switch active pet"
            >
              <Avatar className="h-6 w-6 shrink-0">
                {activePet.avatarKey && (
                  <AvatarImage
                    src={getAvatarUrl(activePet.avatarKey)!}
                    alt={activePet.name}
                  />
                )}
                <AvatarFallback className="text-xs bg-muted">
                  {activePet.name.slice(0, 2).toUpperCase()}
                </AvatarFallback>
              </Avatar>
              <span className="font-medium text-foreground truncate max-w-[120px]">
                {activePet.name}
              </span>
              <ChevronDown className="h-3 w-3 text-muted-foreground" />
            </DropdownMenuTrigger>
            <DropdownMenuContent align="start" className="w-[200px]">
              {pets.map((pet) => (
                <DropdownMenuItem
                  key={pet.id}
                  onClick={() => setActivePet(pet.id)}
                  className="flex items-center gap-2 cursor-pointer"
                >
                  <Avatar className="h-6 w-6 shrink-0">
                    {pet.avatarKey && (
                      <AvatarImage
                        src={getAvatarUrl(pet.avatarKey)!}
                        alt={pet.name}
                      />
                    )}
                    <AvatarFallback className="text-xs bg-muted">
                      {pet.name.slice(0, 2).toUpperCase()}
                    </AvatarFallback>
                  </Avatar>
                  <span className="flex-1 text-sm truncate">{pet.name}</span>
                  <Badge variant="secondary" className="text-xs shrink-0">
                    {pet.species.name}
                  </Badge>
                  {pet.id === activePetId && (
                    <span
                      className="w-2 h-2 rounded-full bg-orange-500 shrink-0"
                      aria-label="Active pet"
                    />
                  )}
                </DropdownMenuItem>
              ))}
              <DropdownMenuSeparator />
              <DropdownMenuItem
                onClick={() => router.push("/onboarding/pet")}
                className="flex items-center gap-2 cursor-pointer"
              >
                <span className="text-orange-500">+</span>
                <span>Add Pet</span>
              </DropdownMenuItem>
            </DropdownMenuContent>
          </DropdownMenu>
        </div>
      )}

      {/* Bottom tab bar */}
      <nav
        className="h-16 bg-card border-t border flex items-center justify-around px-2"
        aria-label="Mobile navigation"
      >
        {/* Home — D-05: href updated to /feed; label stays "Home" */}
        <Link
          href="/feed"
          className={`flex flex-col items-center gap-0.5 px-3 py-2 text-xs ${
            isHomePage ? "text-orange-500" : "text-muted-foreground"
          }`}
        >
          <Home className="h-5 w-5" aria-hidden="true" />
          <span>Home</span>
        </Link>

        {/* Explore — placeholder, Phase 1 */}
        <span
          aria-disabled="true"
          className="flex flex-col items-center gap-0.5 px-3 py-2 text-xs text-muted-foreground/50 cursor-not-allowed"
        >
          <Compass className="h-5 w-5" aria-hidden="true" />
          <span>Explore</span>
        </span>

        {/* Post — center, accent-filled. D-01: opens PostTypeSheet */}
        <button
          type="button"
          aria-label="Create post"
          onClick={() => setPostTypeSheetOpen(true)}
          className="flex flex-col items-center"
        >
          <span className="bg-orange-500 text-white rounded-full p-3 flex items-center justify-center">
            <Plus className="h-5 w-5" aria-hidden="true" />
          </span>
        </button>

        {/* Notifications — placeholder, Phase 1 */}
        <span
          aria-disabled="true"
          className="flex flex-col items-center gap-0.5 px-3 py-2 text-xs text-muted-foreground/50 cursor-not-allowed"
        >
          <Bell className="h-5 w-5" aria-hidden="true" />
          <span>Alerts</span>
        </span>

        {/* Profile (My Pets) */}
        <Link
          href="/pets"
          className={`flex flex-col items-center gap-0.5 px-3 py-2 text-xs ${
            isPetsPage ? "text-orange-500" : "text-muted-foreground"
          }`}
        >
          <User className="h-5 w-5" aria-hidden="true" />
          <span>Profile</span>
        </Link>
      </nav>

      {/* PostTypeSheet — D-01: bottom Sheet with Photo/Story/Milestone choices */}
      <PostTypeSheet
        open={postTypeSheetOpen}
        onOpenChange={setPostTypeSheetOpen}
      />
    </div>
  );
}