"use client";

import { useState, useCallback } from "react";
import { useSession } from "next-auth/react";
import toast from "react-hot-toast";
import {
  useVoteStore,
  selectRemaining,
  DAILY_VOTE_QUOTA,
} from "@/lib/store";
import { useLoginModalStore } from "@/lib/login-modal-store";
import type { Artist } from "@/types/artist";

interface UseVoteActionResult {
  /** 当前投票目标艺人（null 时弹窗关闭） */
  target: Artist | null;
  /** 今日剩余票数 */
  remaining: number;
  /** 每日总额度（常量，供 UI 文案展示） */
  dailyQuota: number;
  /** 触发投票（自动检查登录态 + 额度） */
  openVote: (artist: Artist) => void;
  /** 关闭投票弹窗 */
  closeVote: () => void;
  /** 确认投票（已登录态下调用） */
  confirmVote: (artist: Artist, count: number) => Promise<void>;
}

/**
 * 投票交互统一入口。
 *
 * 规则：
 *  - 每用户每日总额度 = 10 票，跨艺人共享。无单艺人上限。
 *  - 未登录 → toast 提示并跳登录页
 *  - 已登录但当日票数已用完 → toast 提示，不打开弹窗
 *  - 弹窗确认后：本地 store 立即扣减 + 调用后端 API（fire-and-forget）
 */
export function useVoteAction(): UseVoteActionResult {
  const { status } = useSession();
  const recordVote = useVoteStore((s) => s.vote);
  const remaining = useVoteStore(selectRemaining);
  const openLogin = useLoginModalStore((s) => s.show);
  const [target, setTarget] = useState<Artist | null>(null);

  const openVote = useCallback(
    (artist: Artist) => {
      if (status === "loading") return;
      if (status === "unauthenticated") {
        toast("请先登录后再为偶像投票");
        setTimeout(openLogin, 350);
        return;
      }
      if (remaining <= 0) {
        toast("今日票数已用完，明天再来吧");
        return;
      }
      setTarget(artist);
    },
    [status, openLogin, remaining],
  );

  const closeVote = useCallback(() => setTarget(null), []);

  const confirmVote = useCallback(
    async (artist: Artist, count: number) => {
      // 1. 本地 store 立即扣减（包含额度校验）
      const success = recordVote(artist.id, count);
      if (!success) {
        toast.error("今日票数不足");
        setTarget(null);
        return;
      }
      toast.success(`已为 ${artist.name} 投出 ${count} 票`);
      setTarget(null);

      // 2. 后台 fire-and-forget 调用真实 API（5 秒超时，失败静默忽略）
      const ctrl = new AbortController();
      const timer = setTimeout(() => ctrl.abort(), 5000);
      fetch("/api/vote", {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({ artistId: artist.id, count }),
        signal: ctrl.signal,
      })
        .catch(() => {})
        .finally(() => clearTimeout(timer));
    },
    [recordVote],
  );

  return {
    target,
    remaining,
    dailyQuota: DAILY_VOTE_QUOTA,
    openVote,
    closeVote,
    confirmVote,
  };
}