/**
 * companion-channels — Built-in webhook adapter.
 *
 * POSTs message as JSON. The recipient field is the webhook URL.
 *
 * Config:
 * {
 *   "type": "webhook",
 *   "method": "POST",
 *   "headers": { "Authorization": "Bearer ..." }
 * }
 */

import type {
  AdapterConfig,
  ChannelAdapter,
  ChannelMessage,
} from "../types.js";

export function createWebhookAdapter(config: AdapterConfig): ChannelAdapter {
  const method = (config.method as string) ?? "POST";
  const extraHeaders = (config.headers as Record<string, string>) ?? {};

  return {
    direction: "outgoing" as const,

    async send(message: ChannelMessage): Promise<void> {
      const res = await fetch(message.recipient, {
        method,
        headers: { "Content-Type": "application/json", ...extraHeaders },
        body: JSON.stringify({
          text: message.text,
          source: message.source,
          metadata: message.metadata,
          timestamp: new Date().toISOString(),
        }),
      });

      if (!res.ok) {
        const err = await res.text().catch(() => "unknown error");
        throw new Error(`Webhook error ${res.status}: ${err}`);
      }
    },
  };
}