import { defineTool, type RegisteredTool } from '../../server.ts'
import type { AttachState } from './attach.ts'

/** The one browser tool that isn't session-bound: enumerate tabs so the caller
 *  can pick one to `start_capture` on. Navigate/eval/wait are the shared
 *  authoring tools (keyed by captureId — see `shared.ts`). */
export function listTabsTool(attachRef: {
	current?: AttachState
}): RegisteredTool {
	return defineTool<Record<string, never>>(
		{
			name: 'list_tabs',
			description:
				'List the open tabs in the attached browser, with their tabId, title '
				+ 'and URL. Call it after attach_browser to pick the tabId to pass to '
				+ 'start_capture.',
			inputSchema: { type: 'object', properties: {} },
		},
		async() => {
			if(!attachRef.current) {
				throw new Error('Not attached. Call attach_browser first.')
			}

			return { tabs: await attachRef.current.handles.listTabs() }
		},
	)
}