import { getSortedChildren } from './get-sorted-children'
import type { Collection } from './types'

const collection: Collection = {
    ids: ['1', '2', '3', '4'],
    entities: new Map([
        ['1', { id: '1' }],
        ['2', { id: '2' }],
        ['3', { id: '3' }],
        ['4', { id: '4' }],
        ['11', { id: '11' }],
        ['12', { id: '12' }],
        ['13', { id: '13' }],
        ['22', { id: '22' }],
        ['44', { id: '44' }],
    ]),
    meta: new Map([
        ['1', { type: 'tree', children: ['11', '12', '13', '14'] }],
        ['2', { type: 'tree', children: ['22'] }],
        ['4', { type: 'tree', children: ['44'] }],
    ]),
}

describe('getSortedChildren', () => {
    describe('with no sort function', () => {
        describe('with parentId', () => {
            it('should return the children if present', () => {
                expect(getSortedChildren(collection, '1', null)).toEqual([
                    '11',
                    '12',
                    '13',
                    '14',
                ])
            })
            it('should return an empty array if no children are present', () => {
                expect(getSortedChildren(collection, '3', null)).toEqual([])
            })
        })

        describe('with a null parentId', () => {
            it('should return root ids', () => {
                expect(getSortedChildren(collection, null, null)).toEqual([
                    '1',
                    '2',
                    '3',
                    '4',
                ])
            })
        })
    })

    describe('with a sort function', () => {
        describe('with parentId', () => {
            it('should return the sorted children', () => {
                const sort = jest.fn().mockReturnValue(['14', '13', '12', '11'])
                expect(getSortedChildren(collection, '1', sort)).toEqual([
                    '14',
                    '13',
                    '12',
                    '11',
                ])
                expect(sort).toBeCalledWith(
                    ['11', '12', '13', '14'],
                    collection.entities,
                    collection.meta
                )
            })
        })

        describe('with a null parentId', () => {
            it('should return sorted root ids', () => {
                const sort = jest.fn().mockReturnValue(['4', '3', '2', '1'])
                expect(getSortedChildren(collection, null, sort)).toEqual([
                    '4',
                    '3',
                    '2',
                    '1',
                ])
                expect(sort).toBeCalledWith(
                    ['1', '2', '3', '4'],
                    collection.entities,
                    collection.meta
                )
            })
        })
    })
})