import { keepPreviousData, useInfiniteQuery, useMutation, useQueryClient } from "@tanstack/react-query";
import { cursorPage, Task, type TaskKind, type TaskStatus } from "@umt/contracts";
import { ListTodo, RotateCcw, Square } from "lucide-react";
import { useState } from "react";
import { Link } from "react-router";
import { toast } from "sonner";
import { apiMutate, apiParsed, cleanParams } from "~/api/parse.ts";
import { type DataColumn, DataTable } from "~/components/console/data-table.tsx";
import { FilterBar, FilterSelect } from "~/components/console/filter-bar.tsx";
import { StatusBadge } from "~/components/console/status-badge.tsx";
import { Button } from "~/components/ui/button.tsx";
import { relTime } from "~/components/workbench/release-fields.ts";
import { errorMessage, TTL_SECOND } from "~/lib/api.ts";

// 业务任务(/tasks):引擎只负责推进,task 表是面向用户的投影;取消只停后续步骤,重试只对失败任务。

const TaskPage = cursorPage(Task);

export const TASK_KIND_LABEL: Record<TaskKind, string> = {
  ingestFeed: "抓取 Feed",
  resolveObservation: "识别资源",
  evaluateAcquisition: "评估候选",
  submitDownload: "提交下载",
  verifyAndImport: "核验入库",
  refreshMetadata: "刷新元数据",
  reconcileLibrary: "资产对账",
  cleanupDownloadCache: "清理缓存",
  resolveDecision: "处理待办",
  agentRun: "Agent 运行",
};

export const TASK_STATUS: Record<
  TaskStatus,
  { label: string; tone: "success" | "warning" | "destructive" | "neutral" }
> = {
  pending: { label: "排队", tone: "neutral" },
  running: { label: "运行中", tone: "neutral" },
  waiting: { label: "等待", tone: "warning" },
  succeeded: { label: "成功", tone: "success" },
  failed: { label: "失败", tone: "destructive" },
  cancelled: { label: "已取消", tone: "neutral" },
  dead: { label: "放弃", tone: "destructive" },
};

const ACTIVE: TaskStatus[] = ["pending", "running", "waiting"];

function subjectLink(t: Task): string | null {
  if (!t.subjectId) return null;
  if (t.subjectType === "download_task") return `/console/tasks/${t.subjectId}`;
  if (t.subjectType === "organization_record") return `/console/organize/${t.subjectId}`;
  if (t.subjectType === "media_entity") return `/console/library/${t.subjectId}`;
  return null;
}

export function BusinessTasks() {
  const [kind, setKind] = useState("");
  const [status, setStatus] = useState("");
  const qc = useQueryClient();
  const list = useInfiniteQuery({
    queryKey: ["tasks", "list", kind, status],
    initialPageParam: undefined as string | undefined,
    placeholderData: keepPreviousData,
    queryFn: ({ pageParam, signal }) =>
      apiParsed(TaskPage, "/api/v1/tasks", {
        params: cleanParams({ kind, status, cursor: pageParam, limit: 50 }),
        signal,
      }),
    getNextPageParam: (last) => last.nextCursor ?? undefined,
    refetchInterval: (q) =>
      q.state.data?.pages.some((p) => p.items.some((t) => ACTIVE.includes(t.status))) ? 5 * TTL_SECOND : false,
  });
  const action = useMutation({
    mutationFn: ({ id, op }: { id: string; op: "cancel" | "retry" }) =>
      apiMutate(`/api/v1/tasks/:id/${op}`, {
        pathParams: { id },
        body: op === "cancel" ? { reason: "控制台取消" } : {},
      }).then((d) => Task.parse(d)),
    onSuccess: (_t, v) => {
      toast.success(v.op === "cancel" ? "已请求取消(只停后续步骤)" : "已重新排队");
      void qc.invalidateQueries({ queryKey: ["tasks"] });
    },
    onError: (e) => toast.error(errorMessage(e)),
  });
  const rows = list.data?.pages.flatMap((p) => p.items);

  const columns: DataColumn<Task>[] = [
    {
      key: "kind",
      header: "任务",
      cell: (t) => {
        const href = subjectLink(t);
        return (
          <div className="min-w-0">
            <p className="font-medium text-foreground">{TASK_KIND_LABEL[t.kind] ?? t.kind}</p>
            {href ? (
              <Link to={href} className="font-mono text-meta text-muted-foreground hover:underline">
                {t.subjectType} · {t.subjectId?.slice(0, 8)}
              </Link>
            ) : (
              <p className="font-mono text-meta text-muted-foreground">{t.subjectType ?? "—"}</p>
            )}
          </div>
        );
      },
    },
    {
      key: "status",
      header: "状态",
      cell: (t) => (
        <div className="flex flex-col items-start gap-1">
          <StatusBadge tone={TASK_STATUS[t.status].tone}>{TASK_STATUS[t.status].label}</StatusBadge>
          {t.waitReason ? <span className="text-micro text-muted-foreground">{t.waitReason}</span> : null}
        </div>
      ),
    },
    {
      key: "attempts",
      header: "尝试",
      hideBelow: "md",
      align: "right",
      cell: (t) => (
        <span className="tabular-nums">
          {t.attempts}/{t.maxAttempts}
        </span>
      ),
    },
    {
      key: "by",
      header: "触发",
      hideBelow: "lg",
      cell: (t) => <span className="text-muted-foreground">{t.triggeredBy ?? "—"}</span>,
    },
    {
      key: "at",
      header: "创建",
      hideBelow: "sm",
      cell: (t) => <span className="whitespace-nowrap text-muted-foreground">{relTime(t.createdAt)}</span>,
    },
    {
      key: "ops",
      header: "",
      align: "right",
      cell: (t) => (
        <div className="flex justify-end gap-1">
          {t.engineRunId ? (
            <Button variant="ghost" size="sm" asChild>
              <Link to={`/console/engine/${encodeURIComponent(t.engineRunId)}`}>引擎</Link>
            </Button>
          ) : null}
          {ACTIVE.includes(t.status) ? (
            <Button
              variant="ghost"
              size="sm"
              disabled={action.isPending}
              onClick={(e) => {
                e.stopPropagation();
                action.mutate({ id: t.id, op: "cancel" });
              }}
            >
              <Square />
              取消
            </Button>
          ) : null}
          {t.status === "failed" || t.status === "dead" ? (
            <Button
              variant="ghost"
              size="sm"
              disabled={action.isPending}
              onClick={(e) => {
                e.stopPropagation();
                action.mutate({ id: t.id, op: "retry" });
              }}
            >
              <RotateCcw />
              重试
            </Button>
          ) : null}
        </div>
      ),
    },
  ];

  return (
    <>
      <FilterBar
        onReset={
          kind || status
            ? () => {
                setKind("");
                setStatus("");
              }
            : undefined
        }
      >
        <FilterSelect
          label="类型"
          value={kind}
          onChange={setKind}
          options={Object.entries(TASK_KIND_LABEL).map(([value, label]) => ({ value, label }))}
        />
        <FilterSelect
          label="状态"
          value={status}
          onChange={setStatus}
          options={Object.entries(TASK_STATUS).map(([value, v]) => ({ value, label: v.label }))}
        />
      </FilterBar>
      <DataTable
        columns={columns}
        rows={rows}
        rowKey={(t) => t.id}
        loading={list.isPending}
        error={list.error}
        onRetry={() => void list.refetch()}
        hasMore={list.hasNextPage}
        onLoadMore={() => void list.fetchNextPage()}
        loadingMore={list.isFetchingNextPage}
        empty={{
          icon: ListTodo,
          title: kind || status ? "没有符合筛选的任务" : "还没有业务任务",
          description: "提交下载、核验入库、缓存清理、对账等后台工作都会记在这里。",
        }}
      />
    </>
  );
}