import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
import {
  type SubtitleApplyRequest,
  SubtitleApplyResult,
  SubtitleParseResponse,
  SubtitleTargetsResponse,
  SubtitleWritesResponse,
  SubtitleWriteView,
} from "@umt/contracts";
import { api } from "~/lib/api.ts";
import { getParsed, parseOrThrow } from "./library.ts";

// 补字幕(docs/plan/subtitles.md):目标视频、解析上传、写入、历史与撤销

export const subtitleKeys = {
  targets: (entityId: string) => ["subtitles", "targets", entityId] as const,
  writes: (entityId: string) => ["subtitles", "writes", entityId] as const,
};

export function useSubtitleTargets(entityId: string, enabled = true) {
  return useQuery({
    queryKey: subtitleKeys.targets(entityId),
    enabled,
    queryFn: ({ signal }) => getParsed(SubtitleTargetsResponse, "/subtitles/targets", { entityId }, signal),
  });
}

export function useSubtitleWrites(entityId: string, enabled = true) {
  return useQuery({
    queryKey: subtitleKeys.writes(entityId),
    enabled,
    queryFn: ({ signal }) => getParsed(SubtitleWritesResponse, "/subtitles/writes", { entityId }, signal),
  });
}

/** 读本地文件为 base64(字幕与 zip 都很小,直接放进 JSON) */
async function fileBase64(f: File): Promise<string> {
  const buf = new Uint8Array(await f.arrayBuffer());
  let s = "";
  for (let i = 0; i < buf.length; i += 0x8000) s += String.fromCharCode(...buf.subarray(i, i + 0x8000));
  return btoa(s);
}

export function useParseSubtitles() {
  return useMutation({
    mutationFn: async ({ entityId, files }: { entityId: string; files: File[] }) =>
      parseOrThrow(
        SubtitleParseResponse,
        await api.post<unknown>("/subtitles/parse", {
          entityId,
          files: await Promise.all(files.map(async (f) => ({ name: f.name, base64: await fileBase64(f) }))),
        }),
        "/subtitles/parse",
      ),
  });
}

export function useApplySubtitles() {
  const qc = useQueryClient();
  return useMutation({
    mutationFn: async (body: SubtitleApplyRequest) =>
      parseOrThrow(SubtitleApplyResult, await api.post<unknown>("/subtitles/apply", body), "/subtitles/apply"),
    onSuccess: (_r, body) => {
      qc.invalidateQueries({ queryKey: subtitleKeys.targets(body.entityId) });
      qc.invalidateQueries({ queryKey: subtitleKeys.writes(body.entityId) });
    },
  });
}

export function useUndoSubtitle(entityId: string) {
  const qc = useQueryClient();
  return useMutation({
    mutationFn: async (id: string) =>
      parseOrThrow(
        SubtitleWriteView,
        await api.post<unknown>(`/subtitles/writes/${id}/undo`),
        "/subtitles/writes/undo",
      ),
    onSuccess: () => {
      qc.invalidateQueries({ queryKey: subtitleKeys.targets(entityId) });
      qc.invalidateQueries({ queryKey: subtitleKeys.writes(entityId) });
    },
  });
}