import type {
  ToolContext,
  ToolExecutionResult,
} from "../../../../tools/types.js";
import { err, getProviderConnection, ok, resolveProvider } from "./shared.js";

export async function run(
  input: Record<string, unknown>,
  _context: ToolContext,
): Promise<ToolExecutionResult> {
  const platform = input.platform as string | undefined;
  const query = (input.query as string) ?? "category:promotions newer_than:90d";
  const maxMessages = input.max_messages as number | undefined;
  const maxSenders = input.max_senders as number | undefined;
  const pageToken = input.page_token as string | undefined;

  try {
    const provider = await resolveProvider(platform);

    if (!provider.senderDigest) {
      return err(
        `The ${provider.displayName} provider does not support sender digest scanning.`,
      );
    }

    const account = input.account as string | undefined;
    const conn = await getProviderConnection(provider, account);
    const result = await provider.senderDigest!(conn, query, {
      maxMessages,
      maxSenders,
      pageToken,
    });

    if (result.senders.length === 0) {
      return ok(
        JSON.stringify({
          senders: [],
          total_scanned: result.totalScanned,
          query_used: result.queryUsed,
          ...(result.truncated ? { truncated: true } : {}),
          message:
            "No emails found matching the query. Try broadening the search (e.g. remove category filter or extend date range).",
        }),
      );
    }

    // Map to snake_case output format for LLM consumption
    const senders = result.senders.map((s) => ({
      id: s.id,
      display_name: s.displayName,
      email: s.email,
      message_count: s.messageCount,
      has_unsubscribe: s.hasUnsubscribe,
      newest_message_id: s.newestMessageId,
      search_query: s.searchQuery,
    }));

    return ok(
      JSON.stringify({
        senders,
        total_scanned: result.totalScanned,
        query_used: result.queryUsed,
        ...(result.truncated ? { truncated: true } : {}),
        note: `message_count reflects emails found per sender within the ${result.totalScanned} messages scanned. Use messaging_archive_by_sender with the sender's search_query to archive their messages.`,
      }),
    );
  } catch (e) {
    return err(e instanceof Error ? e.message : String(e));
  }
}