import type {
  SubtitleLanguage,
  SubtitleParsedItem,
  SubtitleSearchResult,
  SubtitleTarget,
  SubtitleWriteView,
} from "@umt/contracts";
import { Download, ExternalLink, FileUp, LoaderCircle, Search, Undo2 } from "lucide-react";
import { useEffect, useId, useMemo, useRef, useState } from "react";
import { toast } from "sonner";
import {
  useApplySubtitles,
  useFetchSubtitle,
  useParseSubtitles,
  useSearchSubtitles,
  useSubtitleTargets,
  useSubtitleWrites,
  useUndoSubtitle,
} from "~/api/subtitles.ts";
import { EmptyState, ErrorState, LoadingState } from "~/components/console/empty-state.tsx";
import { StatusBadge } from "~/components/console/status-badge.tsx";
import { Button } from "~/components/ui/button.tsx";
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogFooter,
  DialogHeader,
  DialogTitle,
} from "~/components/ui/dialog.tsx";
import { Input } from "~/components/ui/input.tsx";
import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from "~/components/ui/select.tsx";
import { Tabs, TabsList, TabsTrigger } from "~/components/ui/tabs.tsx";
import { relTime } from "~/components/workbench/release-fields.ts";
import { errorMessage } from "~/lib/api.ts";
import { cn } from "~/lib/utils.ts";

// 补字幕(docs/plan/subtitles.md):上传字幕 / zip → 预览(语言、写到哪一集,可改)→ 写到视频同目录;下面是历史,可撤销。

export const SUBTITLE_LANGUAGE_LABEL: Record<SubtitleLanguage, string> = {
  "zh-Hans": "简中",
  "zh-Hant": "繁中",
  "zh-Hans&en": "简英双语",
  "zh-Hant&en": "繁英双语",
  "zh&ja": "中日双语",
  "zh&ko": "中韩双语",
  en: "英文",
  ja: "日文",
  ko: "韩文",
  unknown: "未知",
};
const SOURCE_LABEL = { upload: "上传", subhd: "SubHD", zimuku: "字幕库" } as const;
const SKIP = "__skip__";
const ACCEPT = ".srt,.ass,.ssa,.vtt,.sub,.sbv,.zip";

const targetLabel = (t: SubtitleTarget) =>
  t.episode !== null
    ? `S${String(t.season ?? 1).padStart(2, "0")}E${String(t.episode).padStart(2, "0")} · ${t.fileName}`
    : t.fileName;

type Row = SubtitleParsedItem & { target: string };

/** 同一后缀的语言(写出来是同一个文件名):双语按中文,与整理规则一致 */
const suffixGroup = (l: SubtitleLanguage) => (l.startsWith("zh-Hant") ? "zh-tw" : l.startsWith("zh") ? "zh-cn" : l);

export function SubtitleDialog({
  entityId,
  title,
  open,
  onOpenChange,
  fromSession,
}: {
  entityId: string;
  title: string;
  open: boolean;
  onOpenChange: (o: boolean) => void;
  /** 原站视图会话:打开时自动下载它当前页的字幕并配对 */
  fromSession?: string;
}) {
  const inputId = useId();
  const input = useRef<HTMLInputElement>(null);
  const targets = useSubtitleTargets(entityId, open);
  const writes = useSubtitleWrites(entityId, open);
  const parse = useParseSubtitles();
  const apply = useApplySubtitles();
  const undo = useUndoSubtitle(entityId);
  const [rows, setRows] = useState<Row[]>([]);
  const [skipped, setSkipped] = useState<{ name: string; reason: string }[]>([]);
  const [dragging, setDragging] = useState(false);
  const [tab, setTab] = useState<"upload" | "online">("upload");
  const list = targets.data?.targets ?? [];
  const fetchPage = useFetchSubtitle();
  const busy = parse.isPending || apply.isPending || fetchPage.isPending;
  const fetchedFrom = useRef<string | null>(null);
  useEffect(() => {
    if (!open || !fromSession || fetchedFrom.current === fromSession) return;
    fetchedFrom.current = fromSession;
    fetchPage
      .mutateAsync({ entityId, sessionId: fromSession })
      .then((r) => {
        setRows((prev) => [...prev, ...r.items.map((it) => ({ ...it, target: it.targetLocationId ?? SKIP }))]);
        setSkipped((prev) => [...prev, ...r.skipped]);
      })
      .catch((err) => toast.error(errorMessage(err, "下载当前字幕失败")));
  }, [open, fromSession, entityId, fetchPage]);

  const load = async (files: File[]) => {
    if (!files.length) return;
    try {
      const r = await parse.mutateAsync({ entityId, files });
      setRows((prev) => [...prev, ...r.items.map((it) => ({ ...it, target: it.targetLocationId ?? SKIP }))]);
      setSkipped((prev) => [...prev, ...r.skipped]);
    } catch (err) {
      toast.error(errorMessage(err, "解析字幕失败"));
    }
  };
  const patch = (id: string, p: Partial<Row>) => setRows((rs) => rs.map((r) => (r.id === id ? { ...r, ...p } : r)));
  const chosen = rows.filter((r) => r.target !== SKIP);
  // 同一个视频选了两份同语言字幕:写入时后一份会被拒绝,先提示
  const dup = useMemo(() => {
    const seen = new Set<string>();
    const out = new Set<string>();
    for (const r of chosen) {
      const k = `${r.target}|${r.language}|${r.ext}`;
      if (seen.has(k)) out.add(r.id);
      seen.add(k);
    }
    return out;
  }, [chosen]);

  const submit = async () => {
    try {
      const r = await apply.mutateAsync({
        entityId,
        source: "upload",
        items: chosen.map((x) => ({
          name: x.name,
          ext: x.ext,
          language: x.language,
          content: x.content,
          targetLocationId: x.target,
          ...(x.source ? { source: x.source } : {}),
          ...(x.sourceRef ? { sourceRef: x.sourceRef } : {}),
        })),
      });
      if (r.written.length) toast.success(`已写入 ${r.written.length} 个字幕`);
      if (r.failed.length) toast.error(r.failed.map((f) => `${f.name}：${f.reason}`).join("\n"));
      setRows((rs) => rs.filter((x) => r.failed.some((f) => f.name === x.name)));
      setSkipped([]);
    } catch (err) {
      toast.error(errorMessage(err, "写入失败"));
    }
  };

  return (
    <Dialog open={open} onOpenChange={(o) => !busy && onOpenChange(o)}>
      <DialogContent className="max-h-[92dvh] overflow-y-auto sm:max-w-3xl">
        <DialogHeader>
          <DialogTitle>补字幕</DialogTitle>
          <DialogDescription>
            {title}：字幕写到视频同目录，文件名是视频名加语言后缀；同名字幕会先备份，可以撤销。
          </DialogDescription>
        </DialogHeader>

        {targets.isPending ? (
          <LoadingState rows={3} />
        ) : targets.error ? (
          <ErrorState error={targets.error} onRetry={() => void targets.refetch()} />
        ) : !list.length ? (
          <EmptyState title="媒体库里还没有这部作品的视频" description="整理入库后才能补字幕。" />
        ) : (
          <div className="min-w-0 space-y-4">
            <Tabs value={tab} onValueChange={(v) => setTab(v as "upload" | "online")}>
              <TabsList>
                <TabsTrigger value="upload">上传</TabsTrigger>
                <TabsTrigger value="online">在线搜索</TabsTrigger>
              </TabsList>
            </Tabs>
            {tab === "upload" ? (
              <label
                htmlFor={inputId}
                onDragOver={(e) => {
                  e.preventDefault();
                  setDragging(true);
                }}
                onDragLeave={() => setDragging(false)}
                onDrop={(e) => {
                  e.preventDefault();
                  setDragging(false);
                  void load([...e.dataTransfer.files]);
                }}
                className={cn(
                  "flex cursor-pointer flex-col items-center gap-1 rounded-lg border border-dashed border-border px-4 py-6 text-center transition-colors hover:border-foreground/40",
                  dragging && "border-foreground/60 bg-accent",
                )}
              >
                {parse.isPending ? <LoaderCircle className="size-5 animate-spin" /> : <FileUp className="size-5" />}
                <span className="text-caption text-foreground">选择或拖入字幕文件</span>
                <span className="text-meta text-muted-foreground">
                  支持 srt / ass / ssa / vtt / sub / sbv 和 zip，可一次选多个
                </span>
                <input
                  ref={input}
                  id={inputId}
                  type="file"
                  multiple
                  accept={ACCEPT}
                  className="sr-only"
                  onChange={(e) => {
                    void load([...(e.target.files ?? [])]);
                    if (input.current) input.current.value = "";
                  }}
                />
              </label>
            ) : (
              <OnlinePanel
                entityId={entityId}
                seasons={[...new Set(list.map((t) => t.season).filter((x): x is number => x !== null))]}
                onFetched={(items, skip) => {
                  setRows((prev) => [...prev, ...items.map((it) => ({ ...it, target: it.targetLocationId ?? SKIP }))]);
                  setSkipped((prev) => [...prev, ...skip]);
                }}
              />
            )}

            {fetchPage.isPending ? (
              <p className="flex items-center gap-2 text-caption text-muted-foreground">
                <LoaderCircle className="size-4 animate-spin" />
                正在下载原站视图当前页的字幕…
              </p>
            ) : null}
            {rows.length ? (
              <ul className="space-y-2">
                {rows.map((r) => (
                  <li
                    key={r.id}
                    className="grid gap-2 rounded-lg border border-border/70 px-3 py-2 sm:grid-cols-[minmax(0,1fr)_8rem_minmax(0,1.2fr)]"
                  >
                    <div className="min-w-0">
                      <p className="truncate text-caption text-foreground" title={r.name}>
                        {r.name.split("/").pop()}
                      </p>
                      <p className="truncate text-meta text-muted-foreground">
                        {[
                          r.archive ? `来自 ${r.archive}` : null,
                          r.episode !== null ? `识别为第 ${r.episode} 集` : null,
                          r.encoding !== "utf-8" ? `${r.encoding} 已转 UTF-8` : null,
                        ]
                          .filter(Boolean)
                          .join(" · ")}
                      </p>
                      {dup.has(r.id) ? <p className="text-meta text-warning">同一集已选了同语言的字幕</p> : null}
                      {(() => {
                        const old = list
                          .find((t) => t.locationId === r.target)
                          ?.existing.find(
                            (x) =>
                              suffixGroup(x.language) === suffixGroup(r.language) && x.fileName.endsWith(`.${r.ext}`),
                          );
                        return old ? (
                          <p className="truncate text-meta text-warning">会覆盖已有的 {old.fileName}（先备份）</p>
                        ) : null;
                      })()}
                    </div>
                    <Select value={r.language} onValueChange={(v) => patch(r.id, { language: v as SubtitleLanguage })}>
                      <SelectTrigger aria-label="语言" className="w-full">
                        <SelectValue />
                      </SelectTrigger>
                      <SelectContent position="popper">
                        {(Object.keys(SUBTITLE_LANGUAGE_LABEL) as SubtitleLanguage[]).map((k) => (
                          <SelectItem key={k} value={k}>
                            {SUBTITLE_LANGUAGE_LABEL[k]}
                          </SelectItem>
                        ))}
                      </SelectContent>
                    </Select>
                    <Select value={r.target} onValueChange={(v) => patch(r.id, { target: v })}>
                      <SelectTrigger aria-label="写到" className="w-full min-w-0">
                        <SelectValue />
                      </SelectTrigger>
                      <SelectContent position="popper">
                        <SelectItem value={SKIP}>不写</SelectItem>
                        {list.map((t) => (
                          <SelectItem key={t.locationId} value={t.locationId}>
                            {targetLabel(t)}
                          </SelectItem>
                        ))}
                      </SelectContent>
                    </Select>
                  </li>
                ))}
              </ul>
            ) : null}
            {skipped.length ? (
              <p className="text-meta text-muted-foreground">
                跳过：{skipped.map((s) => `${s.name}（${s.reason}）`).join("、")}
              </p>
            ) : null}

            <History items={writes.data?.items ?? []} onUndo={(w) => undo.mutate(w.id)} undoing={undo.isPending} />
          </div>
        )}

        <DialogFooter>
          {rows.length ? (
            <Button
              variant="ghost"
              onClick={() => {
                setRows([]);
                setSkipped([]);
              }}
              disabled={busy}
            >
              清空
            </Button>
          ) : null}
          <Button onClick={() => void submit()} disabled={busy || !chosen.length}>
            {apply.isPending ? <LoaderCircle className="animate-spin" /> : null}
            {chosen.length ? `写入 ${chosen.length} 个字幕` : "写入"}
          </Button>
        </DialogFooter>
      </DialogContent>
    </Dialog>
  );
}

function History({
  items,
  onUndo,
  undoing,
}: {
  items: SubtitleWriteView[];
  onUndo: (w: SubtitleWriteView) => void;
  undoing: boolean;
}) {
  if (!items.length) return null;
  return (
    <section aria-label="补字幕记录" className="border-t border-border/60 pt-3">
      <h3 className="mb-2 text-meta font-semibold text-muted-foreground">补字幕记录</h3>
      <ul className="space-y-1">
        {items.slice(0, 30).map((w) => (
          <li key={w.id} className="flex min-w-0 items-center gap-2 text-caption">
            <span
              className={cn("min-w-0 flex-1 truncate", w.undoneAt && "text-muted-foreground line-through")}
              title={w.relativePath}
            >
              {w.fileName}
            </span>
            <span className="shrink-0 text-meta text-muted-foreground">
              {SOURCE_LABEL[w.source]} · {relTime(w.createdAt)}
            </span>
            {w.replaced && !w.undoneAt ? <StatusBadge className="shrink-0">覆盖了旧字幕</StatusBadge> : null}
            {w.undoneAt ? (
              <StatusBadge className="shrink-0">已撤销</StatusBadge>
            ) : (
              <Button
                variant="ghost"
                size="xs"
                disabled={undoing}
                onClick={() => onUndo(w)}
                title={w.replaced ? "删掉这次写入，还原旧字幕" : "删掉这次写入的字幕"}
              >
                <Undo2 />
                撤销
              </Button>
            )}
          </li>
        ))}
      </ul>
    </section>
  );
}

/** 在线搜索:已启用的字幕站(SubHD、字幕库);下载的字幕进上面同一个预览 */
function OnlinePanel({
  entityId,
  seasons,
  onFetched,
}: {
  entityId: string;
  seasons: number[];
  onFetched: (items: SubtitleParsedItem[], skipped: { name: string; reason: string }[]) => void;
}) {
  const search = useSearchSubtitles();
  const fetch = useFetchSubtitle();
  const [keyword, setKeyword] = useState("");
  const [season, setSeason] = useState<string>(seasons.length === 1 ? String(seasons[0]) : "all");
  const [episode, setEpisode] = useState("");
  const [fetching, setFetching] = useState<string | null>(null);
  const data = search.data;

  const run = () =>
    search.mutate(
      {
        entityId,
        ...(keyword.trim() ? { keyword: keyword.trim() } : {}),
        ...(season !== "all" ? { season: Number(season) } : {}),
        ...(episode.trim() && /^\d+$/.test(episode.trim()) ? { episode: Number(episode.trim()) } : {}),
      },
      { onError: (err) => toast.error(errorMessage(err, "搜索失败")) },
    );
  const take = async (r: SubtitleSearchResult) => {
    setFetching(`${r.siteId}${r.ref}`);
    try {
      const p = await fetch.mutateAsync({ entityId, siteId: r.siteId, ref: r.ref, title: r.title });
      if (!p.items.length) toast.error("这个字幕包里没有能用的字幕文件");
      else toast.success(`已下载 ${p.items.length} 个字幕，检查下面的配对后写入`);
      onFetched(p.items, p.skipped);
    } catch (err) {
      toast.error(errorMessage(err, "下载失败"));
    } finally {
      setFetching(null);
    }
  };

  return (
    <div className="min-w-0 space-y-3">
      <form
        className="flex flex-wrap items-center gap-2"
        onSubmit={(e) => {
          e.preventDefault();
          run();
        }}
      >
        <Input
          value={keyword}
          onChange={(e) => setKeyword(e.target.value)}
          placeholder="默认按作品名搜，可另填关键词"
          aria-label="关键词"
          className="min-w-48 flex-1"
        />
        {seasons.length ? (
          <>
            <Select value={season} onValueChange={setSeason}>
              <SelectTrigger aria-label="季" className="w-28">
                <SelectValue />
              </SelectTrigger>
              <SelectContent position="popper">
                <SelectItem value="all">全部季</SelectItem>
                {seasons.map((n) => (
                  <SelectItem key={n} value={String(n)}>
                    第 {n} 季
                  </SelectItem>
                ))}
              </SelectContent>
            </Select>
            <Input
              value={episode}
              onChange={(e) => setEpisode(e.target.value)}
              placeholder="集（可空）"
              aria-label="集"
              inputMode="numeric"
              className="w-24"
            />
          </>
        ) : null}
        <Button type="submit" disabled={search.isPending}>
          {search.isPending ? <LoaderCircle className="animate-spin" /> : <Search />}
          搜索
        </Button>
      </form>

      {data?.noSites ? (
        <p className="text-caption text-muted-foreground">
          还没有启用的字幕站。到「站点 → 添加站点 → 字幕站」添加 SubHD 或字幕库。
        </p>
      ) : null}
      {data?.errors.length ? (
        <p className="text-meta text-warning">{data.errors.map((e) => `${e.siteName}：${e.reason}`).join("；")}</p>
      ) : null}
      {data && !data.noSites && !data.results.length ? (
        <p className="text-caption text-muted-foreground">
          没搜到（用了：{data.keywords.join("、") || "无"}）。可以换个关键词，或去掉季集限制再试。
        </p>
      ) : null}
      {data?.results.length ? (
        <ul className="max-h-80 space-y-1.5 overflow-y-auto">
          {data.results.map((r) => {
            const key = `${r.siteId}${r.ref}`;
            return (
              <li key={key} className="flex min-w-0 items-center gap-2 rounded-lg border border-border/70 px-3 py-2">
                <div className="min-w-0 flex-1">
                  <p className="truncate text-caption text-foreground" title={r.title}>
                    {r.title}
                  </p>
                  <p className="truncate text-meta text-muted-foreground">
                    {[
                      r.siteName,
                      r.languages.join(" / ") || null,
                      r.format,
                      r.downloads !== null ? `下载 ${r.downloads}` : null,
                      r.publishedAt ? (r.publishedAt.includes("T") ? relTime(r.publishedAt) : r.publishedAt) : null,
                    ]
                      .filter(Boolean)
                      .join(" · ")}
                  </p>
                </div>
                <Button asChild variant="ghost" size="icon-sm" title="在字幕站打开">
                  <a href={r.pageUrl} target="_blank" rel="noreferrer" aria-label="在字幕站打开">
                    <ExternalLink />
                  </a>
                </Button>
                <Button size="sm" variant="outline" disabled={fetching !== null} onClick={() => void take(r)}>
                  {fetching === key ? <LoaderCircle className="animate-spin" /> : <Download />}
                  下载
                </Button>
              </li>
            );
          })}
        </ul>
      ) : null}
    </div>
  );
}