/**
 * External dependencies
 */
import { useSelect } from '@wordpress/data';

/**
 * Internal dependencies
 */
import { Campaign } from '~/marketing/types';
import { STORE_KEY } from '~/marketing/data-multichannel/constants';
import {
	CampaignsState,
	Campaign as APICampaign,
	ApiFetchError,
} from '~/marketing/data-multichannel/types';
import { useRegisteredChannels } from '~/marketing/hooks';

type UseCampaignsType = {
	loading: boolean;
	data?: Array< Campaign >;
	error?: ApiFetchError;
	meta?: {
		total?: number;
	};
};

/**
 * Custom hook to get campaigns.
 *
 * @param  page    Page number. First page is `1`.
 * @param  perPage Page size, i.e. number of records in one page.
 */
export const useCampaigns = (
	page: number,
	perPage: number
): UseCampaignsType => {
	const { data: channels } = useRegisteredChannels();

	return useSelect(
		( select ) => {
			const { hasFinishedResolution, getCampaigns } = select( STORE_KEY );
			const campaignsState = getCampaigns< CampaignsState >(
				page,
				perPage
			);

			const convert = ( campaign: APICampaign ): Campaign => {
				const channel = channels?.find(
					( el ) => el.slug === campaign.channel
				);

				return {
					id: `${ campaign.channel }|${ campaign.id }`,
					title: campaign.title,
					description: '',
					cost: `${ campaign.cost.currency } ${ campaign.cost.value }`,
					manageUrl: campaign.manage_url,
					icon: channel?.icon || '',
					channelName: channel?.title || '',
					channelSlug: campaign.channel,
				};
			};

			const error =
				campaignsState.pages && campaignsState.pages[ page ]?.error;

			const data =
				campaignsState.pages &&
				campaignsState.pages[ page ]?.data?.map( convert );

			return {
				loading: ! hasFinishedResolution( 'getCampaigns', [
					page,
					perPage,
				] ),
				data,
				error,
				meta: {
					total: campaignsState.total,
				},
			};
		},
		[ page, perPage ]
	);
};