import type { LocationQuery } from 'vue-router'
import { SITE_KEY_MAX } from '@/lib/directory'
import {
	DEFAULT_PAGE_SIZE,
	PAGE_SIZES,
	SEARCH_MAX_LENGTH,
	firstQueryValue,
	parsePositiveInteger,
} from '@/lib/pageQuery'

export type ArticleStatus = 'online' | 'draft'

export const DEFAULT_ARTICLE_SORT = 'updated_at:desc'
export const ARTICLE_SORT_FIELDS = ['title', 'status', 'created_at', 'updated_at'] as const
export type ArticleSortField = (typeof ARTICLE_SORT_FIELDS)[number]

export const SEO_FILTER = 'suggestions'

export interface ArticleListQuery {
	page: number
	size: number
	q: string
	status: ArticleStatus | ''
	sort: string
	site: string
	seo: '' | typeof SEO_FILTER
}

const SORT_PATTERN = new RegExp(`^(${ARTICLE_SORT_FIELDS.join('|')}):(asc|desc)$`)

function validSort(value: string) {
	return SORT_PATTERN.test(value) && value !== DEFAULT_ARTICLE_SORT ? value : ''
}

export function effectiveSort(sort: string) {
	return sort || DEFAULT_ARTICLE_SORT
}

export function nextSort(current: string, field: ArticleSortField) {
	const [activeField, direction] = effectiveSort(current).split(':')
	return `${field}:${activeField === field && direction === 'asc' ? 'desc' : 'asc'}`
}

export function parseArticleQuery(query: LocationQuery): ArticleListQuery {
	const page = firstQueryValue(query.page)
	const size = Number(firstQueryValue(query.size))
	const status = firstQueryValue(query.status)
	return {
		page: parsePositiveInteger(page) ?? 1,
		size: PAGE_SIZES.includes(size) ? size : DEFAULT_PAGE_SIZE,
		q: firstQueryValue(query.q).slice(0, SEARCH_MAX_LENGTH),
		status: status === 'online' || status === 'draft' ? status : '',
		sort: validSort(firstQueryValue(query.sort)),
		site: firstQueryValue(query.site).slice(0, SITE_KEY_MAX),
		seo: firstQueryValue(query.seo) === SEO_FILTER ? SEO_FILTER : '',
	}
}

export function toRouteQuery(query: ArticleListQuery) {
	const route: Record<string, string> = {}
	if (query.page !== 1) {
		route.page = String(query.page)
	}
	if (query.size !== DEFAULT_PAGE_SIZE) {
		route.size = String(query.size)
	}
	if (query.q) {
		route.q = query.q
	}
	if (query.status) {
		route.status = query.status
	}
	if (effectiveSort(query.sort) !== DEFAULT_ARTICLE_SORT) {
		route.sort = query.sort
	}
	if (query.site) {
		route.site = query.site
	}
	if (query.seo) {
		route.seo = query.seo
	}
	return route
}

export function sameArticleQuery(left: ArticleListQuery, right: ArticleListQuery) {
	return (
		left.page === right.page &&
		left.size === right.size &&
		left.q === right.q &&
		left.status === right.status &&
		left.site === right.site &&
		left.seo === right.seo &&
		effectiveSort(left.sort) === effectiveSort(right.sort)
	)
}