import { useMemo, useState } from "react";
import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
import {
  createNeCollection,
  deleteCollectionJob,
  fetchCollectionJob,
  fetchCollectionRuns,
  fetchEligibleNe,
  fetchNeCollections,
  pauseCollectionJob,
  startCollectionJob,
  retryFailedCollectionJob,
  collectionJobDownloadUrl,
  collectionRunDownloadUrl,
} from "../services/api";
import { queryKeys } from "../constants/queryKeys";
import { useI18n } from "../i18n";
import { useToast } from "../hooks/useToast";
import type { CollectionJobDetail, CollectionJobItem, EligibleNeItem } from "../types";
import { pageCount } from "../utils/display";
import { formatSystemTime } from "../utils/time";

const POLL_MS = 2000;
const ELIGIBLE_PAGE_SIZE = 20;

export function CollectPage() {
  const { t } = useI18n();
  const { showOk, showError } = useToast();
  const queryClient = useQueryClient();

  const [commands, setCommands] = useState("");
  const [title, setTitle] = useState("");
  const [selectedMap, setSelectedMap] = useState<Record<string, EligibleNeItem>>({});
  const [pickSelectedIds, setPickSelectedIds] = useState<string[]>([]);
  const [neKeyword, setNeKeyword] = useState("");
  const [nePage, setNePage] = useState(1);
  const [jobPage, setJobPage] = useState(1);
  const [expandedJobId, setExpandedJobId] = useState("");

  const selectedIds = useMemo(() => Object.keys(selectedMap), [selectedMap]);
  const selectedList = useMemo(() => Object.values(selectedMap), [selectedMap]);

  const eligibleQuery = useQuery({
    queryKey: queryKeys.collectionEligibleNe(nePage, neKeyword),
    queryFn: () =>
      fetchEligibleNe({ page: nePage, pageSize: ELIGIBLE_PAGE_SIZE, keyword: neKeyword }),
    staleTime: 5000,
  });

  const jobsQuery = useQuery({
    queryKey: queryKeys.neCollections(jobPage),
    queryFn: () => fetchNeCollections({ page: jobPage, pageSize: 20 }),
    staleTime: 1000,
    refetchInterval: (q) => {
      const items = q.state.data?.items ?? [];
      return items.some((j) => j.status === "running") ? POLL_MS : false;
    },
  });

  const detailQuery = useQuery({
    queryKey: queryKeys.neCollectionDetail(expandedJobId),
    queryFn: () => fetchCollectionJob(expandedJobId),
    enabled: Boolean(expandedJobId),
    staleTime: 500,
    refetchInterval: (q) => (q.state.data?.job.status === "running" ? POLL_MS : false),
  });

  const jobs = jobsQuery.data?.items ?? [];
  const jobActive = jobs.some((j) => j.status === "running");
  const expandedJobRunning =
    Boolean(expandedJobId) &&
    (jobs.find((j) => j.id === expandedJobId)?.status === "running" || detailQuery.data?.job.status === "running");
  const autoPolling = jobActive || expandedJobRunning;

  const refreshAll = async () => {
    await Promise.all([
      queryClient.invalidateQueries({ queryKey: queryKeys.neCollectionsAll }),
      expandedJobId
        ? queryClient.invalidateQueries({ queryKey: queryKeys.neCollectionDetail(expandedJobId) })
        : Promise.resolve(),
      expandedJobId
        ? queryClient.invalidateQueries({ queryKey: queryKeys.neCollectionRunsAll })
        : Promise.resolve(),
    ]);
  };

  const invalidateJobs = async (jobId?: string) => {
    await queryClient.invalidateQueries({ queryKey: queryKeys.neCollectionsAll });
    if (jobId) {
      await queryClient.invalidateQueries({ queryKey: queryKeys.neCollectionDetail(jobId) });
      await queryClient.invalidateQueries({ queryKey: queryKeys.neCollectionRunsAll });
    }
  };

  const pauseMutation = useMutation({
    mutationFn: pauseCollectionJob,
    onSuccess: async (job) => {
      showOk(t("collect.paused"));
      await invalidateJobs(job.id);
    },
    onError: (err) => showError(String(err)),
  });

  const startJobMutation = useMutation({
    mutationFn: startCollectionJob,
    onSuccess: async (job) => {
      showOk(t("collect.started", { id: job.id }));
      setExpandedJobId(job.id);
      await invalidateJobs(job.id);
    },
    onError: (err) => showError(String(err)),
  });

  const retryFailedMutation = useMutation({
    mutationFn: retryFailedCollectionJob,
    onSuccess: async (job) => {
      showOk(t("collect.retryFailedDone"));
      setExpandedJobId(job.id);
      await invalidateJobs(job.id);
    },
    onError: (err) => showError(String(err)),
  });

  const deleteMutation = useMutation({
    mutationFn: deleteCollectionJob,
    onSuccess: async (_, jobId) => {
      showOk(t("collect.deleted"));
      if (expandedJobId === jobId) setExpandedJobId("");
      await invalidateJobs();
    },
    onError: (err) => showError(String(err)),
  });

  const createMutation = useMutation({
    mutationFn: () =>
      createNeCollection({
        title: title.trim(),
        commands,
        ne_ids: selectedIds,
      }),
    onSuccess: async (job) => {
      showOk(t("collect.created", { id: job.id }));
      setExpandedJobId(job.id);
      await queryClient.invalidateQueries({ queryKey: queryKeys.neCollectionsAll });
      await queryClient.invalidateQueries({ queryKey: queryKeys.neCollectionDetail(job.id) });
    },
    onError: (err) => showError(String(err)),
  });

  const addNe = (row: EligibleNeItem) => {
    setSelectedMap((prev) => (prev[row.id] ? prev : { ...prev, [row.id]: row }));
  };

  const addBatchNe = (rows: EligibleNeItem[]) => {
    if (rows.length === 0) return;
    setSelectedMap((prev) => {
      const next = { ...prev };
      for (const row of rows) {
        if (!next[row.id]) next[row.id] = row;
      }
      return next;
    });
  };

  const removeNe = (id: string) => {
    setSelectedMap((prev) => {
      const next = { ...prev };
      delete next[id];
      return next;
    });
  };

  const clearSelected = () => setSelectedMap({});

  const eligibleItems = eligibleQuery.data?.items ?? [];
  const selectablePickItems = eligibleItems.filter((row) => !selectedMap[row.id]);
  const allPickSelected = selectablePickItems.length > 0 && selectablePickItems.every((row) => pickSelectedIds.includes(row.id));
  const batchPickCount = pickSelectedIds.length;
  const neTotal = eligibleQuery.data?.total ?? 0;
  const nePages = pageCount(neTotal, ELIGIBLE_PAGE_SIZE);

  const jobTotal = jobsQuery.data?.total ?? 0;
  const jobPages = pageCount(jobTotal, 20);

  const commandLines = useMemo(
    () =>
      commands
        .split("\n")
        .map((l) => l.trim())
        .filter((l) => l && !l.startsWith("#")).length,
    [commands],
  );

  const actionPending =
    pauseMutation.isPending ||
    startJobMutation.isPending ||
    retryFailedMutation.isPending ||
    deleteMutation.isPending;

  return (
    <div className="page-stack">
      <section className="panel collect-create-panel">
        <div>
          <h2>{t("collect.create.title")}</h2>
          <p className="panel__hint">{t("collect.create.hint")}</p>
        </div>

        <div className="form-grid form-grid--single">
          <label className="form-grid__full">
            {t("collect.form.jobTitle")}
            <input value={title} onChange={(e) => setTitle(e.target.value)} placeholder={t("collect.form.jobTitlePh")} />
          </label>
          <label className="form-grid__full">
            {t("collect.form.commands")}
            <textarea
              className="collect-commands"
              rows={8}
              value={commands}
              onChange={(e) => setCommands(e.target.value)}
              placeholder={t("collect.form.commandsPh")}
            />
          </label>
        </div>
        <p className="panel__hint">{t("collect.form.commandsHint")}</p>

        <div className="collect-selected-block">
          <div className="collect-selected-block__head">
            <h3>{t("collect.create.selectedTitle")}</h3>
            <span className="collect-meta">{t("collect.create.selectedCount", { count: selectedList.length })}</span>
            {selectedList.length > 0 ? (
              <button type="button" className="link-btn" onClick={clearSelected}>
                {t("collect.create.clearSelected")}
              </button>
            ) : null}
          </div>
          {selectedList.length === 0 ? (
            <p className="panel__hint">{t("collect.create.selectedEmpty")}</p>
          ) : (
            <div className="collect-selected-list">
              {selectedList.map((row) => (
                <div key={row.id} className="collect-selected-chip">
                  <span className="collect-selected-chip__main">
                    <strong>{row.name || row.ip_address}</strong>
                    <span className="collect-selected-chip__meta">
                      {row.ip_address}
                      {row.vendor ? ` · ${row.vendor}` : ""}
                    </span>
                  </span>
                  <button type="button" className="link-btn" onClick={() => removeNe(row.id)}>
                    {t("collect.create.remove")}
                  </button>
                </div>
              ))}
            </div>
          )}
        </div>

        <div className="collect-pick-block">
          <div className="panel__toolbar">
            <div>
              <h3>{t("collect.create.pickTitle")}</h3>
              <p className="panel__hint">{t("collect.create.pickHint")}</p>
            </div>
            <div className="table-actions">
              <button
                type="button"
                className="link-btn"
                disabled={batchPickCount === 0}
                onClick={() => {
                  const rows = eligibleItems.filter((x) => pickSelectedIds.includes(x.id) && !selectedMap[x.id]);
                  addBatchNe(rows);
                  setPickSelectedIds([]);
                }}
              >
                {t("collect.create.addBatch", { count: batchPickCount })}
              </button>
              <button type="button" onClick={() => eligibleQuery.refetch()} disabled={eligibleQuery.isFetching}>
                {eligibleQuery.isFetching ? t("common.refreshing") : t("common.refresh")}
              </button>
            </div>
          </div>
          <div className="collect-pick-filters">
            <label className="collect-runs-filter">
              {t("collect.create.filterKeyword")}
              <input
                type="search"
                value={neKeyword}
                placeholder={t("collect.create.filterKeywordPh")}
                onChange={(e) => {
                  setNeKeyword(e.target.value);
                  setNePage(1);
                  setPickSelectedIds([]);
                }}
              />
            </label>
          </div>
          {eligibleQuery.isLoading ? <p>{t("common.refreshing")}</p> : null}
          {!eligibleQuery.isLoading && eligibleItems.length === 0 ? (
            <p>{t("collect.create.pickEmpty")}</p>
          ) : (
            <table>
              <thead>
                <tr>
                  <th>
                    <input
                      type="checkbox"
                      checked={allPickSelected}
                      onChange={(e) => {
                        if (e.target.checked) {
                          setPickSelectedIds(selectablePickItems.map((row) => row.id));
                          return;
                        }
                        setPickSelectedIds([]);
                      }}
                      aria-label="pick all"
                    />
                  </th>
                  <th>{t("managedNe.col.name")}</th>
                  <th>{t("managedNe.col.vendor")}</th>
                  <th>{t("managedNe.col.ip")}</th>
                  <th>{t("managedNe.col.connect")}</th>
                  <th />
                </tr>
              </thead>
              <tbody>
                {eligibleItems.map((row) => {
                  const picked = Boolean(selectedMap[row.id]);
                  return (
                    <tr key={row.id}>
                      <td>
                        <input
                          type="checkbox"
                          checked={pickSelectedIds.includes(row.id)}
                          disabled={picked}
                          onChange={(e) => {
                            if (picked) return;
                            setPickSelectedIds((prev) =>
                              e.target.checked ? [...new Set([...prev, row.id])] : prev.filter((id) => id !== row.id),
                            );
                          }}
                        />
                      </td>
                      <td>{row.name || row.ip_address}</td>
                      <td>{row.vendor}</td>
                      <td>{row.ip_address}</td>
                      <td>
                        <span className="conn-pill conn-pill--up">{row.connect_status}</span>
                      </td>
                      <td className="table-actions">
                        <button
                          type="button"
                          className="link-btn"
                          disabled={picked}
                          onClick={() => {
                            addNe(row);
                            setPickSelectedIds((prev) => prev.filter((id) => id !== row.id));
                          }}
                        >
                          {picked ? t("collect.create.added") : t("collect.create.add")}
                        </button>
                      </td>
                    </tr>
                  );
                })}
              </tbody>
            </table>
          )}
          {neTotal > 0 ? (
            <div className="pager">
              <div className="pager__meta">
                {t("common.pagerMeta", { total: neTotal, page: nePage, pages: nePages })}
              </div>
              <div className="pager__controls">
                <button
                  className="pager__btn"
                  disabled={nePage <= 1}
                  onClick={() => {
                    setNePage(nePage - 1);
                    setPickSelectedIds([]);
                  }}
                >
                  {t("common.prevPage")}
                </button>
                <button
                  className="pager__btn"
                  disabled={nePage >= nePages}
                  onClick={() => {
                    setNePage(nePage + 1);
                    setPickSelectedIds([]);
                  }}
                >
                  {t("common.nextPage")}
                </button>
              </div>
            </div>
          ) : null}
        </div>

        <div className="panel__actions">
          <span className="collect-meta">{t("collect.create.meta", { ne: selectedIds.length, cmd: commandLines })}</span>
          <button
            type="button"
            disabled={selectedIds.length === 0 || commandLines === 0 || createMutation.isPending}
            onClick={() => createMutation.mutate()}
          >
            {createMutation.isPending ? t("collect.create.creating") : t("collect.create.create")}
          </button>
        </div>
      </section>

      <section className="panel">
        <div className="panel__toolbar">
          <div>
            <h2>{t("collect.jobs.title")}</h2>
            {autoPolling ? (
              <p className="panel__hint panel__hint--live">
                {t("collect.jobs.autoRefresh")}
                {jobsQuery.isFetching ? ` · ${t("common.refreshing")}` : ""}
              </p>
            ) : null}
          </div>
          <button type="button" onClick={refreshAll} disabled={jobsQuery.isFetching}>
            {jobsQuery.isFetching ? t("common.refreshing") : t("common.refresh")}
          </button>
        </div>
        <table>
          <thead>
            <tr>
              <th>{t("collect.jobs.col.title")}</th>
              <th>{t("collect.jobs.col.status")}</th>
              <th>{t("collect.jobs.col.progress")}</th>
              <th>{t("collect.jobs.col.created")}</th>
              <th>{t("collect.jobs.col.lastRun")}</th>
              <th>{t("collect.jobs.col.actions")}</th>
            </tr>
          </thead>
          <tbody>
            {(jobsQuery.data?.items ?? []).map((job) => (
              <JobRow
                key={job.id}
                job={job}
                expanded={expandedJobId === job.id}
                detail={expandedJobId === job.id ? detailQuery.data : undefined}
                onToggle={() => setExpandedJobId(expandedJobId === job.id ? "" : job.id)}
                onPause={() => pauseMutation.mutate(job.id)}
                onStart={() => startJobMutation.mutate(job.id)}
                onRetryFailed={() => retryFailedMutation.mutate(job.id)}
                onDelete={() => {
                  if (window.confirm(t("collect.confirmDelete"))) deleteMutation.mutate(job.id);
                }}
                actionPending={actionPending}
                startPending={startJobMutation.isPending}
              />
            ))}
          </tbody>
        </table>
        <div className="pager">
          <div className="pager__meta">{t("common.pagerMeta", { total: jobTotal, page: jobPage, pages: jobPages })}</div>
          <div className="pager__controls">
            <button className="pager__btn" disabled={jobPage <= 1} onClick={() => setJobPage(jobPage - 1)}>
              {t("common.prevPage")}
            </button>
            <button className="pager__btn" disabled={jobPage >= jobPages} onClick={() => setJobPage(jobPage + 1)}>
              {t("common.nextPage")}
            </button>
          </div>
        </div>
      </section>
    </div>
  );
}

function JobRow({
  job,
  expanded,
  detail,
  onToggle,
  onPause,
  onStart,
  onRetryFailed,
  onDelete,
  actionPending,
  startPending,
}: {
  job: CollectionJobItem;
  expanded: boolean;
  detail?: CollectionJobDetail;
  onToggle: () => void;
  onPause: () => void;
  onStart: () => void;
  onRetryFailed: () => void;
  onDelete: () => void;
  actionPending: boolean;
  startPending: boolean;
}) {
  const { t } = useI18n();
  const canPause = job.status === "running";
  const canStart = job.status !== "running";
  const canRetryFailed = job.status !== "running" && job.fail_count > 0;
  const canDelete = job.status !== "running";
  const hasResults = (job.output_count ?? 0) > 0;

  const downloadResults = () => {
    window.location.assign(collectionJobDownloadUrl(job.id));
  };
  return (
    <>
      <tr>
        <td>{job.title}</td>
        <td>{job.status}</td>
        <td>
          {job.success_count}/{job.ne_count} {t("collect.jobs.ok")}, {job.fail_count} {t("collect.jobs.fail")}
        </td>
        <td>{formatSystemTime(job.created_at)}</td>
        <td>{job.last_run_at ? formatSystemTime(job.last_run_at) : t("common.empty")}</td>
        <td className="table-actions">
          <button type="button" className="link-btn" onClick={onToggle}>
            {expanded ? t("collect.jobs.collapse") : t("collect.jobs.expand")}
          </button>
          {canPause ? (
            <button type="button" className="link-btn" disabled={actionPending} onClick={onPause}>
              {t("collect.jobs.pause")}
            </button>
          ) : null}
          {canStart ? (
            <button type="button" className="link-btn" disabled={actionPending} onClick={onStart}>
              {startPending ? t("collect.jobs.starting") : t("collect.jobs.start")}
            </button>
          ) : null}
          {canRetryFailed ? (
            <button type="button" className="link-btn" disabled={actionPending} onClick={onRetryFailed}>
              {t("collect.jobs.retryFailed")}
            </button>
          ) : null}
          <button
            type="button"
            className="link-btn"
            disabled={actionPending || !hasResults}
            onClick={downloadResults}
          >
            {t("collect.jobs.downloadResults")}
          </button>
          {canDelete ? (
            <button type="button" className="link-btn link-btn--danger" disabled={actionPending} onClick={onDelete}>
              {t("collect.jobs.delete")}
            </button>
          ) : null}
        </td>
      </tr>
      {expanded ? (
        <tr>
          <td colSpan={6}>
            <JobRunsPanel
              jobId={job.id}
              jobStatus={job.status}
              failCount={job.fail_count}
              commands={detail?.job.commands ?? ""}
              onRetryFailed={onRetryFailed}
              retryPending={actionPending}
            />
          </td>
        </tr>
      ) : null}
    </>
  );
}

const RUN_PAGE_SIZE = 20;
const RUN_STATUS_OPTIONS = ["pending", "running", "success", "fail", "cancelled"] as const;

function JobRunsPanel({
  jobId,
  jobStatus,
  failCount,
  commands,
  onRetryFailed,
  retryPending,
}: {
  jobId: string;
  jobStatus: string;
  failCount: number;
  commands: string;
  onRetryFailed: () => void;
  retryPending: boolean;
}) {
  const { t } = useI18n();
  const [runPage, setRunPage] = useState(1);
  const [runStatus, setRunStatus] = useState("");
  const [runKeyword, setRunKeyword] = useState("");

  const runsQuery = useQuery({
    queryKey: queryKeys.neCollectionRuns(jobId, runPage, runStatus, runKeyword),
    queryFn: () =>
      fetchCollectionRuns({
        jobId,
        page: runPage,
        pageSize: RUN_PAGE_SIZE,
        status: runStatus,
        keyword: runKeyword,
      }),
    staleTime: 500,
    refetchInterval: jobStatus === "running" ? 2000 : false,
  });

  const clearRunFilters = () => {
    setRunStatus("");
    setRunKeyword("");
    setRunPage(1);
  };

  const runTotal = runsQuery.data?.total ?? 0;
  const runPages = pageCount(runTotal, RUN_PAGE_SIZE);
  const runs = runsQuery.data?.items ?? [];

  return (
    <div className="collect-runs-panel">
      {jobStatus === "running" ? (
        <p className="panel__hint panel__hint--live">{t("collect.jobs.runsInProgress")}</p>
      ) : null}
      {commands ? <pre className="collect-cmd-preview">{commands}</pre> : null}
      <div className="collect-runs-toolbar">
        <label className="collect-runs-filter">
          {t("collect.runs.filterDevice")}
          <input
            type="search"
            value={runKeyword}
            placeholder={t("collect.runs.deviceKeywordPh")}
            onChange={(e) => {
              setRunKeyword(e.target.value);
              setRunPage(1);
            }}
          />
        </label>
        <label className="collect-runs-filter">
          {t("collect.runs.filterStatus")}
          <select
            value={runStatus}
            onChange={(e) => {
              setRunStatus(e.target.value);
              setRunPage(1);
            }}
          >
            <option value="">{t("collect.runs.allStatus")}</option>
            {RUN_STATUS_OPTIONS.map((st) => (
              <option key={st} value={st}>
                {st}
              </option>
            ))}
          </select>
        </label>
        {runStatus || runKeyword ? (
          <button type="button" className="link-btn" onClick={clearRunFilters}>
            {t("common.clearFilters")}
          </button>
        ) : null}
        {jobStatus !== "running" && failCount > 0 ? (
          <button type="button" className="link-btn" disabled={retryPending} onClick={onRetryFailed}>
            {t("collect.jobs.retryFailed")}
          </button>
        ) : null}
      </div>
      {runsQuery.isLoading ? <p>{t("common.refreshing")}</p> : null}
      {!runsQuery.isLoading && runs.length === 0 ? <p>{t("common.empty")}</p> : null}
      {runs.length > 0 ? (
        <table>
          <thead>
            <tr>
              <th>{t("managedNe.col.name")}</th>
              <th>{t("managedNe.col.ip")}</th>
              <th>{t("collect.runs.status")}</th>
              <th>{t("collect.runs.message")}</th>
              <th>{t("collect.runs.download")}</th>
            </tr>
          </thead>
          <tbody>
            {runs.map((run) => (
              <tr key={run.id}>
                <td>{run.ne_name}</td>
                <td>{run.ne_ip}</td>
                <td>{run.status}</td>
                <td>
                  {run.message ? (
                    <div className="collect-run-message" title={run.message}>
                      {run.message}
                    </div>
                  ) : (
                    t("common.empty")
                  )}
                </td>
                <td>
                  {run.has_output ? (
                    <a className="link-btn" href={collectionRunDownloadUrl(run.id)} target="_blank" rel="noreferrer">
                      {t("collect.runs.downloadFile")}
                    </a>
                  ) : (
                    t("common.empty")
                  )}
                </td>
              </tr>
            ))}
          </tbody>
        </table>
      ) : null}
      {runTotal > 0 ? (
        <div className="pager">
          <div className="pager__meta">{t("common.pagerMeta", { total: runTotal, page: runPage, pages: runPages })}</div>
          <div className="pager__controls">
            <button className="pager__btn" disabled={runPage <= 1} onClick={() => setRunPage(runPage - 1)}>
              {t("common.prevPage")}
            </button>
            <button className="pager__btn" disabled={runPage >= runPages} onClick={() => setRunPage(runPage + 1)}>
              {t("common.nextPage")}
            </button>
          </div>
        </div>
      ) : null}
    </div>
  );
}