import type { LocationQuery } from 'vue-router'
import { t } from '@/i18n'
import {
	DEFAULT_PAGE_SIZE,
	PAGE_SIZES,
	firstQueryValue,
	parsePositiveInteger,
} from '@/lib/pageQuery'

export const ENTRY_SORT_FIELDS = ['id', 'created_at', 'updated_at'] as const
export type EntrySortField = (typeof ENTRY_SORT_FIELDS)[number]
export type EntrySortDirection = 'asc' | 'desc'

export const DEFAULT_ENTRY_SORT = 'updated_at:desc'

export interface EntryListQuery {
	page: number
	size: number
	q: string
	sort: string
}

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

export function parseEntryQuery(query: LocationQuery): EntryListQuery {
	const size = parsePositiveInteger(firstQueryValue(query.size))
	const sort = firstQueryValue(query.sort)
	return {
		page: parsePositiveInteger(firstQueryValue(query.page)) ?? 1,
		size: size !== null && PAGE_SIZES.includes(size) ? size : DEFAULT_PAGE_SIZE,
		q: '',
		sort: SORT_PATTERN.test(sort) ? sort : DEFAULT_ENTRY_SORT,
	}
}

export function toEntryRouteQuery(query: EntryListQuery) {
	const route: Record<string, string> = {}
	if (query.size !== DEFAULT_PAGE_SIZE) {
		route.size = String(query.size)
	}
	if (query.sort !== DEFAULT_ENTRY_SORT) {
		route.sort = query.sort
	}
	if (query.page !== 1) {
		route.page = String(query.page)
	}
	return route
}

export function sameEntryQuery(left: EntryListQuery, right: EntryListQuery) {
	return left.page === right.page && left.size === right.size && left.sort === right.sort
}

export function sortParts(sort: string) {
	const [field, direction] = sort.split(':') as [EntrySortField, EntrySortDirection]
	return { field, direction }
}

export function withSortField(sort: string, field: EntrySortField) {
	return `${field}:${sortParts(sort).direction}`
}

export function withOppositeDirection(sort: string) {
	const { field, direction } = sortParts(sort)
	return `${field}:${direction === 'asc' ? 'desc' : 'asc'}`
}

export function sortFieldLabel(field: EntrySortField) {
	if (field === 'id') {
		return t('ID')
	}
	return field === 'created_at' ? t('Created') : t('Last updated')
}

export function sortDirectionLabel(sort: string) {
	return sortParts(sort).direction === 'asc' ? t('Sort descending') : t('Sort ascending')
}

export function entryCaption(name: string, sort: string) {
	const { field, direction } = sortParts(sort)
	if (sort === DEFAULT_ENTRY_SORT) {
		return t('{0}, sorted by last updated, newest first', [name])
	}
	const column = { id: t('id'), created_at: t('created'), updated_at: t('updated') }[field]
	return t('{0}, sorted by {1}, {2}', [
		name,
		column,
		direction === 'desc' ? t('descending') : t('ascending'),
	])
}