/**
 * External dependencies
 */
import { map, values } from 'lodash';
import { EMPTY_ARRAY } from '@nelio-content/constants';
import { createIndexedSelector, isDefined } from '@nelio-content/utils';
import type {
	Maybe,
	PostId,
	SocialMessage,
	SocialMessageSummary,
	Uuid,
} from '@nelio-content/types';

/**
 * Internal dependencies
 */
import type { State } from '../../config';

export function getSocialMessage(
	state: State,
	id?: Uuid
): Maybe< SocialMessage > {
	return id ? state.entities.messages.byId[ id ] : undefined;
}

export const getSocialMessagesRelatedToPost = createIndexedSelector(
	( state: State, postId?: PostId ): ReadonlyArray< SocialMessage > => {
		const summaries =
			!! postId && state.entities.messages.byRelatedPost[ postId ];
		if ( ! summaries ) {
			return EMPTY_ARRAY;
		}

		const validMessages = filterOutInvalidAutoMessages( state, summaries );
		return map( validMessages, ( { id } ) =>
			getSocialMessage( state, id )
		).filter( isDefined );
	},
	( state: State, postId?: PostId ) => ( {
		key: postId || 0,
		dependants: [
			!! postId && state.entities.messages.byRelatedPost[ postId ],
			state.entities.messages.byId,
			state.social.profiles.byId,
		],
	} )
);

export const getSocialMessageIdsRelatedToPost = createIndexedSelector(
	( state: State, postId?: PostId ): ReadonlyArray< Uuid > => {
		return map( getSocialMessagesRelatedToPost( state, postId ), 'id' );
	},
	( state: State, postId?: PostId ) => ( {
		key: postId || 0,
		dependants: [ getSocialMessagesRelatedToPost( state, postId ) ],
	} )
);

export const getRecurringMessages = createIndexedSelector(
	(
		state: State,
		recurrenceGroup?: Uuid
	): ReadonlyArray< SocialMessage > => {
		return recurrenceGroup
			? values( state.entities.messages.byId ).filter(
					( m ) => m.recurrenceGroup === recurrenceGroup
			  )
			: [];
	},
	( state: State, recurrenceGroup?: Uuid ) => ( {
		key: recurrenceGroup || 0,
		dependants: [ state.entities.messages.byId ],
	} )
);

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

function filterOutInvalidAutoMessages(
	state: State,
	items: ReadonlyArray< SocialMessageSummary >
): ReadonlyArray< SocialMessageSummary > {
	return items.filter( ( sum ): sum is SocialMessageSummary => {
		if ( 'social' !== sum.type ) {
			return true;
		}

		const item = state.entities.messages.byId[ sum.id ];
		if ( ! item ) {
			return false;
		}

		const profile = state.social.profiles.byId[ item.profileId ];
		if ( ! profile ) {
			return false;
		}

		if (
			'publication' === item.auto &&
			0 >= profile.publicationFrequency
		) {
			return false;
		}

		if (
			[ 'timeline', 'reshare' ].includes( item.auto ?? '' ) &&
			0 >= profile.reshareFrequency
		) {
			return false;
		}

		return true;
	} );
}