// <LinkedAccounts> — the accounts linked to one agent, one row each: kind,
// name, host, and a delete action on every row but the agent's own account.
// Reads `GET /api/hives/{hive}/agents/{agent}/linked-accounts`, which carries
// names and hosts only, never a credential.
//
// Fetched on mount, after a delete, and whenever `version` changes;
// `AgentsPage` bumps it when a link dialog closes, so an account linked there
// shows up without waiting for a reload.
//
// Its state belongs to one agent: callers key it by hive and agent, so
// switching agents remounts it instead of showing the previous agent's rows.
import { useEffect, useState } from "preact/hooks";
import { ApiErrorPanel } from "@hive/shared/api-error-panel.js";
import { readApiError, type ProblemDetails } from "@hive/shared/api-error.js";
import { Badge } from "@hive/shared/badge.js";
import { ConfirmDialog } from "../../ui/confirm-dialog/ConfirmDialog.js";
import "./LinkedAccounts.css";

type AccountKind = "matrix" | "forgejo" | "github";

// Mirrors `linked_accounts::LinkedAccount`.
interface LinkedAccount {
  kind: AccountKind;
  name: string;
  host: string | null;
  reserved: boolean;
}

// The DELETE route for one account, beside the PUT that links it.
function accountUrl(hive: string, agent: string, a: LinkedAccount): string {
  const base = `/api/hives/${encodeURIComponent(hive)}/agents/${encodeURIComponent(agent)}`;
  switch (a.kind) {
    case "matrix":
      return `${base}/matrix-accounts/${encodeURIComponent(a.name)}`;
    case "forgejo":
      return `${base}/forge-accounts/${encodeURIComponent(a.name)}`;
    case "github":
      return `${base}/github-account`;
  }
}

export function LinkedAccounts({
  hive,
  agent,
  version,
}: {
  hive: string;
  agent: string;
  version: number;
}) {
  const [accounts, setAccounts] = useState<LinkedAccount[] | null>(null);
  const [error, setError] = useState<ProblemDetails | null>(null);
  // Bumped after a delete, so the list is fetched again.
  const [reload, setReload] = useState(0);
  // The row whose delete confirmation is open; null means closed.
  const [deleteTarget, setDeleteTarget] = useState<LinkedAccount | null>(null);
  // Matrix only: log the token out at its homeserver before deleting.
  const [revoke, setRevoke] = useState(false);
  const [deleting, setDeleting] = useState(false);
  const [deleteError, setDeleteError] = useState<ProblemDetails | null>(null);

  useEffect(() => {
    let cancelled = false;
    (async () => {
      const r = await fetch(
        `/api/hives/${encodeURIComponent(hive)}/agents/${encodeURIComponent(agent)}/linked-accounts`,
      );
      if (!r.ok) {
        if (!cancelled) setError(await readApiError(r));
        return;
      }
      const data = (await r.json()) as LinkedAccount[];
      if (cancelled) return;
      setAccounts(data);
      setError(null);
    })().catch((e: unknown) => {
      if (!cancelled) setError({ detail: String(e) });
    });
    return () => {
      cancelled = true;
    };
  }, [hive, agent, version, reload]);

  function openDelete(a: LinkedAccount) {
    setDeleteTarget(a);
    setRevoke(false);
    setDeleteError(null);
  }

  async function confirmDelete() {
    if (!deleteTarget) return;
    setDeleting(true);
    try {
      const url = accountUrl(hive, agent, deleteTarget);
      const r = await fetch(
        deleteTarget.kind === "matrix" && revoke ? `${url}?revoke=true` : url,
        { method: "DELETE" },
      );
      // A 404 means the account the dialog is about is already gone — the
      // end state the delete wanted — so it closes the same as a success.
      if (!r.ok && r.status !== 404) {
        setDeleteError(await readApiError(r));
        return;
      }
      setDeleteTarget(null);
      setReload((n) => n + 1);
    } catch (e: unknown) {
      setDeleteError({ detail: String(e) });
    } finally {
      setDeleting(false);
    }
  }

  const dialog = (
    <ConfirmDialog
      open={deleteTarget !== null}
      label="delete linked account"
      onCancel={() => setDeleteTarget(null)}
      onConfirm={() => void confirmDelete()}
      confirmLabel="delete"
      confirmDisabled={deleting}
    >
      {deleteTarget ? (
        <>
          <p>
            Delete the {deleteTarget.kind} account{" "}
            <strong>{deleteTarget.name}</strong>
            {deleteTarget.host ? (
              <>
                {" "}
                on <strong>{deleteTarget.host}</strong>
              </>
            ) : null}{" "}
            from <strong>{agent}</strong>? Every stored version of its token is
            removed from the swarm secret store. The agent is not told.
          </p>
          {deleteTarget.kind === "matrix" ? (
            <label>
              <input
                type="checkbox"
                checked={revoke}
                onChange={(e) =>
                  setRevoke((e.target as HTMLInputElement).checked)
                }
              />{" "}
              also log the token out at the homeserver; if that fails, the
              account is kept
            </label>
          ) : null}
          {deleteError ? (
            <ApiErrorPanel context="delete failed" problem={deleteError} />
          ) : null}
        </>
      ) : null}
    </ConfirmDialog>
  );

  if (error) {
    return (
      <Badge
        tone="negative"
        value="accounts unavailable"
        title={error.detail ?? "listing linked accounts failed"}
      />
    );
  }
  if (accounts === null) return <span class="ui-linked-accounts-muted">…</span>;
  if (accounts.length === 0) {
    return <span class="ui-linked-accounts-muted">none linked</span>;
  }
  return (
    <>
      <ul class="ui-linked-accounts">
        {accounts.map((a) => (
          <li key={`${a.kind}/${a.name}`}>
            <Badge label={a.kind} value={a.name} />
            <span class="ui-linked-accounts-host">{a.host ?? "—"}</span>
            {a.reserved ? (
              <Badge
                value="own account"
                title="the agent's own account, which the swarm mints"
              />
            ) : (
              <Badge
                variant="quiet"
                value="delete"
                title={`delete the ${a.kind} account ${a.name}`}
                onClick={() => openDelete(a)}
              />
            )}
          </li>
        ))}
      </ul>
      {dialog}
    </>
  );
}