/**
 * External dependencies
 */
import type { AnyAction } from '@nab/types';

/**
 * Internal dependencies
 */
import { INIT_STATE } from './config';
import { EMPTY_ARRAY } from '../constants';
import type { State } from './types';
import type { Action } from './actions';

export default function reducer(
	state = INIT_STATE,
	action: AnyAction
): State {
	return actualReducer( state, action as Action ) ?? state;
}

function actualReducer( state: State, action: Action ): State {
	switch ( action.type ) {
		case 'SET_POSITION':
			return {
				...state,
				position: action.position,
			};

		case 'SET_TAB':
			return {
				...state,
				tab: action.tab,
			};

		case 'SET_STATUS':
			return {
				...state,
				status: action.status,
			};

		case 'SET_CLOUD_CONNECTION':
			return {
				...state,
				cloudStatus: action.connected ? 'reachable' : 'unreachable',
			};

		case 'SET_GDPR_STATUS':
			return {
				...state,
				gdprStatus: action.status,
			};

		case 'ADD_NEW_PAGE':
			return {
				...state,
				navigation: [
					{
						name: '',
						url: action.url,
						date: new Date().toISOString(),
						events: EMPTY_ARRAY,
						heatmapClicks: EMPTY_ARRAY,
					},
					...state.navigation,
				],
			};

		case 'SET_PAGE_NAME': {
			const [ page, ...navigation ] = state.navigation;
			if ( ! page ) {
				return state;
			}

			return {
				...state,
				navigation: [ { ...page, name: action.name }, ...navigation ],
			};
		}

		case 'SET_SETTINGS':
			return {
				...state,
				settings: {
					...state.settings,
					...action.settings,
				},
			};

		case 'SET_ALTERNATIVE':
			return {
				...state,
				cookies: {
					...state.cookies,
					alternative: action.value,
				},
				newCookies: {
					...state.newCookies,
					alternative: action.value,
				},
			};

		case 'SET_SEGMENTATION':
			return {
				...state,
				cookies: {
					...state.cookies,
					segmentation: action.value,
				},
				newCookies: {
					...state.newCookies,
					segmentation: action.value,
				},
			};

		case 'SET_NEW_ALTERNATIVE':
			return {
				...state,
				newCookies: {
					...state.newCookies,
					alternative: action.value,
				},
			};

		case 'SET_NEW_ACTIVE_SEGMENTS':
			return {
				...state,
				newCookies: {
					...state.newCookies,
					segmentation: {
						...state.newCookies.segmentation,
						activeSegments: {
							...state.newCookies.segmentation.activeSegments,
							[ action.experimentId ]: action.segments,
						},
					},
				},
			};

		case 'SET_VIEWS':
			return {
				...state,
				cookies: {
					...state.cookies,
					views: action.value,
				},
			};

		case 'ADD_VIEW_EVENT':
		case 'ADD_CONVERSION_EVENT': {
			const [ page, ...navigation ] = state.navigation;
			if ( ! page ) {
				return state;
			}

			return {
				...state,
				navigation: [
					{ ...page, events: [ action.event, ...page.events ] },
					...navigation,
				],
			};
		}

		case 'ADD_CLICK_EVENT': {
			const [ page, ...navigation ] = state.navigation;
			if ( ! page ) {
				return state;
			}

			return {
				...state,
				navigation: [
					{
						...page,
						heatmapClicks: [ action.event, ...page.heatmapClicks ],
					},
					...navigation,
				],
			};
		}

		case 'SET_HIGHLIGHTED_CLICK':
			return {
				...state,
				highlightedClick: action.selector,
			};
	}
}