"use client";

import Image from "next/image";
import Link from "next/link";
import { useCallback, useEffect, useRef, useState } from "react";
import BackButton from "@/app/components/BackButton";
import {
  isActive,
  statusLabels,
  type TranscriptionState,
  type TranscriptionStatus,
} from "@/lib/stt/types";

type Video = {
  aweme_id: string;
  desc: string;
  cover_url: string;
  duration_ms: number;
  author: { nickname: string };
  transcription: TranscriptionState;
};
const filters: ("all" | TranscriptionStatus)[] = [
  "all",
  "PENDING",
  "QUEUED",
  "PROCESSING",
  "SUCCEEDED",
  "FAILED",
];

export default function SttVideosPage() {
  const [videos, setVideos] = useState<Video[]>([]);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState<string | null>(null);
  const [notice, setNotice] = useState("");
  const [submitting, setSubmitting] = useState<Set<string>>(new Set());
  const [batchSubmitting, setBatchSubmitting] = useState(false);
  const [filter, setFilter] = useState<"all" | TranscriptionStatus>("all");
  const fetching = useRef(false);
  const fetchVideos = useCallback(async () => {
    if (fetching.current) return;
    fetching.current = true;
    try {
      const response = await fetch("/api/admin/stt/videos", {
        cache: "no-store",
      });
      if (!response.ok) throw new Error("读取转写列表失败");
      const data: { videos: Video[] } = await response.json();
      setVideos(data.videos);
      setError(null);
    } catch (err) {
      setError(err instanceof Error ? err.message : "读取失败");
    } finally {
      setLoading(false);
      fetching.current = false;
    }
  }, []);
  useEffect(() => {
    void fetchVideos();
    const timer = setInterval(() => {
      void fetchVideos();
    }, 5000);
    return () => clearInterval(timer);
  }, [fetchVideos]);

  async function handleTranscribe(awemeId: string) {
    setSubmitting((prev) => new Set(prev).add(awemeId));
    try {
      const response = await fetch("/api/stt", {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({ awemeId }),
      });
      const data = await response.json();
      if (!response.ok) throw new Error(data.error || "任务入队失败");
      setVideos((prev) =>
        prev.map((video) =>
          video.aweme_id === awemeId
            ? { ...video, transcription: data }
            : video,
        ),
      );
    } catch (err) {
      setNotice(err instanceof Error ? err.message : "任务入队失败");
    } finally {
      setSubmitting((prev) => {
        const next = new Set(prev);
        next.delete(awemeId);
        return next;
      });
    }
  }
  async function handleBatch() {
    setBatchSubmitting(true);
    try {
      const response = await fetch("/api/stt/batch", { method: "POST" });
      const data = await response.json();
      if (!response.ok) throw new Error(data.error || "批量入队失败");
      setNotice(`已加入 ${data.queued} 个转写任务；关闭页面后仍会继续处理。`);
      await fetchVideos();
    } catch (err) {
      setNotice(err instanceof Error ? err.message : "批量入队失败");
    } finally {
      setBatchSubmitting(false);
    }
  }
  const count = (status: TranscriptionStatus) =>
    videos.filter((v) => v.transcription.status === status).length;
  const eligible = videos.filter(
    (v) =>
      v.transcription.transcript === null && !isActive(v.transcription.status),
  ).length;
  const shown = videos.filter(
    (v) => filter === "all" || v.transcription.status === filter,
  );

  return (
    <main className="min-h-screen bg-gray-50 p-6">
      <div className="mx-auto max-w-7xl space-y-4">
        <BackButton />
        <h1 className="text-2xl font-semibold text-gray-900">视频文字转写</h1>
        <p className="text-sm text-gray-600">
          已完成 {count("SUCCEEDED")} · 处理中 {count("PROCESSING")} · 排队中{" "}
          {count("QUEUED")} · 失败 {count("FAILED")} · 待转写 {count("PENDING")}
        </p>
        {error && (
          <p role="alert" className="text-red-700">
            {error}
          </p>
        )}
        {notice && (
          <output className="block text-sm text-gray-700">{notice}</output>
        )}
        <div className="flex flex-wrap items-center justify-between gap-3">
          <div className="flex flex-wrap gap-2">
            {filters.map((value) => (
              <button
                type="button"
                key={value}
                onClick={() => setFilter(value)}
                className={`rounded px-3 py-2 text-sm ${filter === value ? "bg-blue-600 text-white" : "bg-white text-gray-700"}`}
              >
                {value === "all"
                  ? `全部 (${videos.length})`
                  : `${statusLabels[value]} (${count(value)})`}
              </button>
            ))}
          </div>
          <button
            type="button"
            onClick={handleBatch}
            disabled={batchSubmitting || !eligible}
            className="rounded bg-blue-600 px-4 py-2 text-sm text-white disabled:opacity-50"
          >
            {batchSubmitting ? "正在加入队列…" : `批量补转 (${eligible})`}
          </button>
        </div>
        <div className="overflow-x-auto rounded border border-gray-200 bg-white">
          <table className="w-full text-left text-sm">
            <thead className="bg-gray-100 text-gray-600">
              <tr>
                <th className="p-3">视频</th>
                <th className="p-3">时长</th>
                <th className="p-3">状态与文字</th>
                <th className="p-3">操作</th>
              </tr>
            </thead>
            <tbody>
              {shown.map((video) => {
                const state = video.transcription;
                const active =
                  isActive(state.status) || submitting.has(video.aweme_id);
                return (
                  <tr
                    key={video.aweme_id}
                    className="border-t border-gray-100 align-top"
                  >
                    <td className="p-3">
                      <div className="flex max-w-sm gap-3">
                        {video.cover_url && (
                          <Image
                            src={video.cover_url}
                            alt=""
                            width={56}
                            height={80}
                            unoptimized
                            className="h-20 w-14 rounded object-cover"
                          />
                        )}
                        <div>
                          <Link
                            className="line-clamp-2 text-blue-700"
                            href={`/aweme/${video.aweme_id}`}
                          >
                            {video.desc || "无描述"}
                          </Link>
                          <p className="mt-1 text-gray-500">
                            @{video.author.nickname}
                          </p>
                        </div>
                      </div>
                    </td>
                    <td className="whitespace-nowrap p-3 text-gray-700">
                      {Math.floor(video.duration_ms / 1000)} 秒
                    </td>
                    <td className="p-3">
                      <p
                        className={
                          state.status === "FAILED"
                            ? "text-red-700"
                            : "text-gray-700"
                        }
                      >
                        {statusLabels[state.status]}
                      </p>
                      {state.error && (
                        <p className="mt-1 max-w-lg text-xs text-red-700">
                          {state.error}
                        </p>
                      )}
                      {state.transcript !== null && (
                        <p className="mt-1 max-w-lg whitespace-pre-wrap text-gray-600">
                          {state.transcript.join("\n") || "未识别到文字"}
                        </p>
                      )}
                    </td>
                    <td className="whitespace-nowrap p-3">
                      <button
                        type="button"
                        disabled={active}
                        onClick={() => handleTranscribe(video.aweme_id)}
                        className="rounded bg-gray-100 px-3 py-2 text-gray-800 disabled:opacity-50"
                      >
                        {active
                          ? "处理中…"
                          : state.status === "FAILED"
                            ? "重试"
                            : state.transcript !== null
                              ? "重新转写"
                              : "开始转写"}
                      </button>
                    </td>
                  </tr>
                );
              })}
            </tbody>
          </table>
          {!shown.length && (
            <p className="p-8 text-center text-gray-500">
              {loading ? "加载中…" : "没有找到视频"}
            </p>
          )}
        </div>
      </div>
    </main>
  );
}