/**
 * Admin-conversation JSONL purge — Task 237.
 *
 * Shared primitive that fires the claude-session-manager's
 * `DELETE /:sessionId` per attached JSONL. Pure JSONL-only: it does not
 * touch the graph. Callers (the `cascadeAdminConversationDelete` engine
 * and `memory-empty-trash`'s defense-in-depth `onEmpty`) own the graph
 * side and decide whether to proceed after the JSONL outcome lands.
 *
 * Contract:
 *   - manager 204 (purged) or 404 (manager never knew the JSONL) both count
 *     as "transcript no longer exists" and proceed to the next sessionId.
 *   - manager 409 is the structural `pty-still-alive` stop check; the loop
 *     halts and the caller surfaces the live sessionId.
 *   - any other status or transport failure halts the loop with
 *     `jsonl-purge-failed`, naming the failing sessionId and the ids already
 *     purged at the failure point.
 *
 * Log lines mirror the Task 217 cascade so a single grep
 * (`[admin-conversation-delete]`) covers both call sites.
 */

export interface PurgeAdminConversationJsonlsArgs {
  /** Used only for log id8; not for routing. */
  sessionId: string;
  /** Used only for log line context; the helper does not enforce isolation
   *  (the caller has already account-scoped the candidate). */
  accountId: string;
  /** Loopback manager base URL — `http://127.0.0.1:${CLAUDE_SESSION_MANAGER_PORT}`. */
  managerBase: string;
  /** Pre-resolved sessionIds to purge. Caller chooses the lookup strategy
   *  (`getConversationClaudeSessionIds` for live conversations,
   *  elementId-based walk for trashed ones). */
  claudeSessionIds: string[];
  fetchImpl?: typeof fetch;
  logger?: (line: string) => void;
}

export type PurgeAdminConversationJsonlsOutcome =
  | { ok: true; claudeSessionIdsPurged: string[] }
  | {
      ok: false;
      reason: "pty-still-alive";
      claudeSessionId: string;
      claudeSessionIdsPurged: string[];
    }
  | {
      ok: false;
      reason: "jsonl-purge-failed";
      claudeSessionId: string;
      claudeSessionIdsPurged: string[];
      status: number;
      message: string;
    };

export async function purgeAdminConversationJsonls(
  args: PurgeAdminConversationJsonlsArgs,
): Promise<PurgeAdminConversationJsonlsOutcome> {
  const fetchImpl = args.fetchImpl ?? fetch;
  const log = args.logger ?? ((line: string) => console.log(line));
  const id8 = args.sessionId.slice(0, 8);

  const purged: string[] = [];
  for (const sessionId of args.claudeSessionIds) {
    const url = `${args.managerBase}/${encodeURIComponent(sessionId)}`;
    let res: Response;
    try {
      res = await fetchImpl(url, { method: "DELETE" });
    } catch (err) {
      const message = err instanceof Error ? err.message : String(err);
      log(
        `[admin-conversation-delete] sessionId=${id8} reason=jsonl-purge-failed claudeSessionId=${sessionId.slice(0, 8)} message=${message}`,
      );
      return {
        ok: false,
        reason: "jsonl-purge-failed",
        claudeSessionId: sessionId,
        claudeSessionIdsPurged: purged,
        status: 0,
        message,
      };
    }
    if (res.status === 204 || res.status === 404) {
      purged.push(sessionId);
      continue;
    }
    if (res.status === 409) {
      log(
        `[admin-conversation-delete] sessionId=${id8} reason=pty-still-alive claudeSessionId=${sessionId.slice(0, 8)}`,
      );
      return {
        ok: false,
        reason: "pty-still-alive",
        claudeSessionId: sessionId,
        claudeSessionIdsPurged: purged,
      };
    }
    let message = `manager returned ${res.status}`;
    try {
      const body = (await res.json()) as { error?: string; detail?: string };
      if (typeof body.detail === "string") message = body.detail;
      else if (typeof body.error === "string") message = body.error;
    } catch {
      // body isn't JSON — keep status-coded message
    }
    log(
      `[admin-conversation-delete] sessionId=${id8} reason=jsonl-purge-failed claudeSessionId=${sessionId.slice(0, 8)} message=${message}`,
    );
    return {
      ok: false,
      reason: "jsonl-purge-failed",
      claudeSessionId: sessionId,
      claudeSessionIdsPurged: purged,
      status: res.status,
      message,
    };
  }

  return { ok: true, claudeSessionIdsPurged: purged };
}