import { describe, it, expect, afterEach, vi } from 'vitest'
import { copyToClipboard } from '../'

interface TSelection {
	rangeCount?: number
	getRangeAt?: (index: number) => string | undefined | null
	removeAllRanges?: () => null
	addRange?: () => null
}

// Custom document type
interface TDocument {
	getSelection: () => TSelection | null
	execCommand: () => boolean
}

// Override default type
declare let document: TDocument

/** Mock functions on document */
function mockDocument(options: TSelection) {
	document.getSelection = () => {
		return options
	}

	document.execCommand = vi.fn()
}

const txt = 'test'

describe('copyToClipboard', () => {
	it('copies text to the clipboard', () => {
		mockDocument({
			rangeCount: 0,
			getRangeAt: () => null,
			removeAllRanges: () => null,
		})

		const writeTextMock = vi.fn()

		Object.defineProperty(navigator, 'clipboard', {
			value: {
				writeText: writeTextMock,
			},
			writable: true,
		})

		copyToClipboard(txt)

		expect(writeTextMock).toHaveBeenCalledWith(txt)
		expect(document.execCommand).not.toHaveBeenCalled()
	})

	it('copies text to the clipboard when text is already selected', () => {
		mockDocument({
			rangeCount: 2,
			getRangeAt: (index: number) => ['a', 'b'][index],
			removeAllRanges: () => null,
			addRange: () => null,
		})

		const writeTextMock = vi.fn()

		Object.defineProperty(navigator, 'clipboard', {
			value: {
				writeText: writeTextMock,
			},
			writable: true,
		})

		copyToClipboard(txt)

		expect(writeTextMock).toHaveBeenCalledWith(txt)
		expect(document.execCommand).not.toHaveBeenCalled()
	})

	it('copies text to the clipboard when text is already selected and navigator.clipboard is unavailable', () => {
		mockDocument({
			rangeCount: 2,
			getRangeAt: (index: number) => ['a', 'b'][index],
			removeAllRanges: () => null,
			addRange: () => null,
		})

		Object.defineProperty(navigator, 'clipboard', {
			value: null,
			writable: true,
		})

		copyToClipboard(txt)

		expect(document.execCommand).toHaveBeenCalledWith('copy')
	})

	it('does not copies text when getSelection is unavailable', () => {
		document.getSelection = vi.fn(() => null)

		expect(copyToClipboard(txt)).toBeUndefined()
	})

	afterEach(() => {
		vi.clearAllMocks()
	})
})