import { useEffect, useState } from "react";
import { Link } from "react-router-dom";
import {
  api,
  type CurrentUser,
  type DockhandContainer,
  type DockhandContainersResponse,
  type IntegrationSummary,
} from "../api/client";
import { useSortable } from "../hooks/useSortable";
import SortableTh from "../components/SortableTh";
import { downloadCsv } from "../utils/csv";

function updateBadge(c: DockhandContainer) {
  if (c.updateAvailable === null) return <span className="text-secondary">—</span>;
  if (!c.updateAvailable) return <span className="badge bg-green-lt text-green">Up to date</span>;
  return (
    <span className="badge bg-yellow-lt text-yellow" title={c.newerVersion ?? undefined}>
      Update available
    </span>
  );
}

function containerStateBadge(state: string) {
  switch (state) {
    case "running":
      return <span className="badge bg-green-lt text-green">Running</span>;
    case "exited":
    case "dead":
      return <span className="badge bg-red-lt text-red">{state === "dead" ? "Dead" : "Exited"}</span>;
    case "paused":
      return <span className="badge bg-yellow-lt text-yellow">Paused</span>;
    case "restarting":
      return <span className="badge bg-blue-lt text-blue">Restarting</span>;
    default:
      return <span className="badge bg-secondary-lt text-secondary">{state}</span>;
  }
}

export default function Docker({ user }: { user: CurrentUser }) {
  const canEdit = user.role === "admin" || user.role === "operator";

  const [integrations, setIntegrations] = useState<IntegrationSummary[] | null>(null);
  const [selectedId, setSelectedId] = useState<number | null>(null);
  const [error, setError] = useState<string | null>(null);

  const [data, setData] = useState<DockhandContainersResponse | null>(null);
  const [loading, setLoading] = useState(false);
  const [actingOnContainer, setActingOnContainer] = useState<string | null>(null);
  const [hostFilter, setHostFilter] = useState("");
  const [checkingUpdates, setCheckingUpdates] = useState(false);

  useEffect(() => {
    api.integrations
      .list()
      .then((res) => {
        const dockhandIntegrations = res.integrations.filter((i) => i.type === "dockhand");
        setIntegrations(dockhandIntegrations);
        if (!selectedId && dockhandIntegrations.length > 0) setSelectedId(dockhandIntegrations[0].id);
      })
      .catch((err) => setError(err instanceof Error ? err.message : String(err)));
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, []);

  const selected = integrations?.find((i) => i.id === selectedId) ?? null;

  function loadContainers(id: number) {
    setLoading(true);
    setError(null);
    api.integrations.dockhand
      .containers(id)
      .then((res) => setData(res))
      .catch((err) => setError(err instanceof Error ? err.message : String(err)))
      .finally(() => setLoading(false));
  }

  useEffect(() => {
    setHostFilter("");
    if (selected?.enabled) {
      loadContainers(selected.id);
    } else {
      setData(null);
    }
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [selectedId]);

  const hosts = [...new Set((data?.containers ?? []).map((c) => c.environmentName))].sort();
  const filteredContainers = (data?.containers ?? []).filter((c) => !hostFilter || c.environmentName === hostFilter);

  const { sorted, sortKey, sortDir, requestSort } = useSortable(filteredContainers);

  function exportCsv() {
    if (!sorted) return;
    downloadCsv(
      "docker-containers.csv",
      ["Container", "Host", "Image", "State", "Status", "Update available"],
      sorted.map((c) => [
        c.name,
        c.environmentName,
        c.image,
        c.state,
        c.status,
        c.updateAvailable === null ? "unknown" : c.updateAvailable ? "yes" : "no",
      ]),
    );
  }

  async function checkForUpdates() {
    if (!selectedId) return;
    setCheckingUpdates(true);
    setError(null);
    try {
      await api.integrations.dockhand.checkForUpdates(selectedId);
      loadContainers(selectedId);
    } catch (err) {
      setError(err instanceof Error ? err.message : String(err));
    } finally {
      setCheckingUpdates(false);
    }
  }

  async function containerAction(c: DockhandContainer, action: "start" | "stop" | "restart") {
    if (!selectedId) return;
    if (action === "stop" && !confirm(`Stop container "${c.name}"?`)) return;
    setActingOnContainer(c.id);
    setError(null);
    try {
      await api.integrations.dockhand[action](selectedId, c.environmentId, c.id);
      loadContainers(selectedId);
    } catch (err) {
      setError(err instanceof Error ? err.message : String(err));
    } finally {
      setActingOnContainer(null);
    }
  }

  return (
    <>
      <h2 className="page-title mb-3">Docker</h2>
      {error && <div className="alert alert-danger">{error}</div>}

      {integrations?.length === 0 ? (
        <div className="card">
          <div className="card-body text-secondary">
            No Dockhand integration configured yet.{" "}
            <Link to="/integrations">Add one under Integrations</Link>.
          </div>
        </div>
      ) : (
        <>
          {integrations && integrations.length > 1 && (
            <div className="mb-3" style={{ maxWidth: 320 }}>
              <select
                className="form-select"
                value={selectedId ?? ""}
                onChange={(e) => setSelectedId(Number(e.target.value))}
              >
                {integrations.map((i) => (
                  <option key={i.id} value={i.id} disabled={!i.enabled}>
                    {i.name}
                    {!i.enabled ? " — disabled" : ""}
                  </option>
                ))}
              </select>
            </div>
          )}

          {selected && !selected.enabled ? (
            <div className="card">
              <div className="card-body text-secondary">
                "{selected.name}" is disabled. Enable it under Integrations → Manage integrations to see its
                containers.
              </div>
            </div>
          ) : (
            <div className="card">
              <div className="card-header">
                <h3 className="card-title">
                  Containers
                  {data && (
                    <span className="text-secondary fw-normal ms-2">
                      {data.summary.running}/{data.summary.total} running
                    </span>
                  )}
                  {data && data.containers.filter((c) => c.updateAvailable).length > 0 && (
                    <span className="text-yellow fw-normal ms-2">
                      {data.containers.filter((c) => c.updateAvailable).length} update(s) available
                    </span>
                  )}
                </h3>
                <div className="card-actions d-flex gap-2">
                  {hosts.length > 1 && (
                    <select
                      className="form-select form-select-sm"
                      style={{ width: "auto" }}
                      value={hostFilter}
                      onChange={(e) => setHostFilter(e.target.value)}
                    >
                      <option value="">All hosts</option>
                      {hosts.map((host) => (
                        <option key={host} value={host}>
                          {host}
                        </option>
                      ))}
                    </select>
                  )}
                  <button className="btn btn-sm btn-outline-secondary" onClick={exportCsv} disabled={!sorted || sorted.length === 0}>
                    Export CSV
                  </button>
                  {canEdit && (
                    <button className="btn btn-sm btn-outline-secondary" onClick={checkForUpdates} disabled={checkingUpdates}>
                      {checkingUpdates ? "Checking…" : "Check for updates"}
                    </button>
                  )}
                  <button
                    className="btn btn-sm btn-outline-secondary"
                    onClick={() => selected && loadContainers(selected.id)}
                    disabled={loading}
                  >
                    {loading ? "Refreshing…" : "Refresh"}
                  </button>
                </div>
              </div>
              <div className="table-responsive">
                <table className="table table-vcenter card-table">
                  <thead>
                    <tr>
                      <SortableTh<DockhandContainer> label="Container" sortKeyName="name" activeKey={sortKey} direction={sortDir} onSort={requestSort} />
                      <SortableTh<DockhandContainer>
                        label="Host"
                        sortKeyName="environmentName"
                        activeKey={sortKey}
                        direction={sortDir}
                        onSort={requestSort}
                      />
                      <SortableTh<DockhandContainer> label="Image" sortKeyName="image" activeKey={sortKey} direction={sortDir} onSort={requestSort} />
                      <SortableTh<DockhandContainer> label="Status" sortKeyName="state" activeKey={sortKey} direction={sortDir} onSort={requestSort} />
                      <SortableTh<DockhandContainer>
                        label="Update"
                        sortKeyName="updateAvailable"
                        activeKey={sortKey}
                        direction={sortDir}
                        onSort={requestSort}
                      />
                      {canEdit && <th className="w-1">Actions</th>}
                    </tr>
                  </thead>
                  <tbody>
                    {sorted?.map((c) => (
                      <tr key={`${c.environmentId}:${c.id}`}>
                        <td>{c.name}</td>
                        <td className="text-secondary">{c.environmentName}</td>
                        <td className="text-secondary">{c.image}</td>
                        <td>
                          {containerStateBadge(c.state)}
                          <div className="text-secondary small">{c.status}</div>
                        </td>
                        <td>{updateBadge(c)}</td>
                        {canEdit && (
                          <td>
                            <div className="btn-list flex-nowrap">
                              {c.state === "running" ? (
                                <>
                                  <button
                                    className="btn btn-sm"
                                    onClick={() => containerAction(c, "restart")}
                                    disabled={actingOnContainer === c.id}
                                  >
                                    Restart
                                  </button>
                                  <button
                                    className="btn btn-sm btn-outline-danger"
                                    onClick={() => containerAction(c, "stop")}
                                    disabled={actingOnContainer === c.id}
                                  >
                                    Stop
                                  </button>
                                </>
                              ) : (
                                <button
                                  className="btn btn-sm btn-primary"
                                  onClick={() => containerAction(c, "start")}
                                  disabled={actingOnContainer === c.id}
                                >
                                  Start
                                </button>
                              )}
                            </div>
                          </td>
                        )}
                      </tr>
                    ))}
                    {data && sorted?.length === 0 && (
                      <tr>
                        <td colSpan={canEdit ? 6 : 5} className="text-secondary text-center">
                          {hostFilter ? `No containers found on "${hostFilter}".` : "No containers found across any environment."}
                        </td>
                      </tr>
                    )}
                  </tbody>
                </table>
              </div>
            </div>
          )}
        </>
      )}
    </>
  );
}