/**
 * Internal dependencies
 */
import { LISTENERS } from './listeners';
import { sendConversions } from './sync';
import { getAllActions, getConvertingGoals } from './utils';
import { once } from '../utils/lodash';
import type { ConvertibleAction, Session } from '../types';

import type { Attributes as ClickAttrs } from '../../../../packages/conversion-action-library/click/types';
import type { Attributes as EngagementAttrs } from '../../../../packages/conversion-action-library/engagement/types';
import type { Attributes as ScrollAttrs } from '../../../../packages/conversion-action-library/scroll/types';
import type { Attributes as TimeAttrs } from '../../../../packages/conversion-action-library/time-on-page/types';

export const initConversionTracking = once( ( session: Session ): void => {
	sendConvertingPageViews( session );
	addActionListeners( session );
} );

// =======
// HELPERS
// =======

function sendConvertingPageViews( session: Session ) {
	const { experiments } = session;

	const events = getConvertingGoals(
		experiments,
		( action ) => action.active && 'nab/page-view' === action.type
	);
	sendConversions( events, session );
}

function addActionListeners( session: Session ) {
	const allActions = getAllActions( session.experiments )
		.filter( ( action ) => action.active )
		.filter( ( action ) => 'nab/page-view' !== action.type )
		.flatMap( ( action ) =>
			isEngagementAction( action )
				? expandEngagementAction( action )
				: [ action ]
		);
	LISTENERS.forEach( ( listener ) =>
		listener( allActions, ( actions ) =>
			sendConversions( actions, session )
		)
	);
}

const isEngagementAction = (
	action: ConvertibleAction
): action is ConvertibleAction< EngagementAttrs > =>
	action.type === 'nab/engagement';

function expandEngagementAction(
	action: ConvertibleAction
): [
	ConvertibleAction< ClickAttrs >,
	ConvertibleAction< ScrollAttrs >,
	ConvertibleAction< TimeAttrs >,
] {
	return [
		{
			...action,
			type: 'nab/click',
			attributes: {
				mode: 'css',
				value: 'a, button, input, textarea, select, summary, [role="button"], [tabindex], [data-clickable="true"]',
				delay: 3,
			},
		},
		{
			...action,
			type: 'nab/scroll',
			attributes: {
				value: 50,
			},
		},
		{
			...action,
			type: 'nab/time-on-page',
			attributes: {
				value: 10,
			},
		},
	];
}