import { afterEach, describe, expect, it, vi } from 'vitest'
import { mount, flushPromises } from '@vue/test-utils'
import { createPinia, setActivePinia } from 'pinia'
import uiPlugin from '@nuxt/ui/vue-plugin'
import router from '@/router'
import ResultPanel from '@/components/ResultPanel.vue'
import ResetRequestView from '../ResetRequestView.vue'

function mockResponse(status: number, body: unknown = null, headers: Record<string, string> = {}) {
	return {
		ok: status >= 200 && status < 300,
		status,
		headers: { get: (name: string) => headers[name] ?? null },
		json: async () => body,
	} as unknown as Response
}

function routeFor(url: string, init?: RequestInit) {
	const method = init?.method ?? 'GET'
	return `${method} ${url}`
}

function fetchRouter(handlers: Record<string, () => Response | Promise<Response>>) {
	return vi.fn((url: string, init?: RequestInit) => {
		const key = routeFor(url, init)
		const handler = handlers[key]
		if (!handler) {
			throw new Error(`Unexpected fetch call: ${key}`)
		}
		return handler()
	})
}

let currentWrapper: Awaited<ReturnType<typeof mount>> | null = null

async function mountResetRequest(
	handlers: Record<string, () => Response | Promise<Response>> = {},
) {
	setActivePinia(createPinia())
	const fetchMock = fetchRouter(handlers)
	global.fetch = fetchMock as unknown as typeof fetch
	await router.push('/register/reset/request')
	const wrapper = mount(ResetRequestView, {
		attachTo: document.body,
		global: {
			plugins: [router, uiPlugin],
		},
	})
	currentWrapper = wrapper
	await flushPromises()
	return { wrapper, fetchMock }
}

function emailInput(wrapper: Awaited<ReturnType<typeof mountResetRequest>>) {
	return wrapper.find('input[placeholder="you@example.com"]')
}

async function fillAndSubmit(
	wrapper: Awaited<ReturnType<typeof mountResetRequest>>,
	email: string,
) {
	await emailInput(wrapper).setValue(email)
	await wrapper.find('form').trigger('submit')
	await flushPromises()
}

afterEach(async () => {
	currentWrapper?.unmount()
	currentWrapper = null
	await router.push('/login')
})

describe('Default — a fresh, empty form', () => {
	it('renders the empty state', async () => {
		const { wrapper } = await mountResetRequest()

		expect(wrapper.find('h1').text()).toBe('Reset your password')
		expect(wrapper.text()).toContain(
			"Enter the email for your account and we'll send you a link to choose a new password.",
		)

		expect((emailInput(wrapper).element as HTMLInputElement).value).toBe('')

		expect(wrapper.find('button[type="submit"]').text()).toBe('Send reset link')

		const footerLink = wrapper.find('a[href="/login"]')
		expect(footerLink.exists()).toBe(true)
		expect(footerLink.text()).toBe('Back to log in')
	})
})

describe('Validation error — an invalid email blocks the request', () => {
	it('never calls the endpoint and shows the field error', async () => {
		const request = vi.fn(() => mockResponse(200))
		const { wrapper } = await mountResetRequest({
			'POST /v1/auth/password-reset': request,
		})

		await fillAndSubmit(wrapper, 'marta@renew')

		expect(request).not.toHaveBeenCalled()
		expect(wrapper.text()).toContain('Enter a full email address, like name@example.com.')
	})
})

describe('Submitting — the field and button are disabled while the request is in flight', () => {
	it('disables the field and shows the loading label', async () => {
		let resolveRequest: (() => void) | null = null
		const { wrapper } = await mountResetRequest({
			'POST /v1/auth/password-reset': () =>
				new Promise((resolve) => {
					resolveRequest = () => resolve(mockResponse(200))
				}),
		})

		await emailInput(wrapper).setValue('marta@renew.example')
		await wrapper.find('form').trigger('submit')
		await flushPromises()

		expect((emailInput(wrapper).element as HTMLInputElement).disabled).toBe(true)
		const submitButton = wrapper.find('button[type="submit"]')
		expect(submitButton.text()).toBe('Sending…')
		expect((submitButton.element as HTMLButtonElement).disabled).toBe(true)

		resolveRequest?.()
		await flushPromises()
	})
})

describe('Sent — any 200 shows the same neutral confirmation', () => {
	it('replaces the form with a ResultPanel and navigates back to log in', async () => {
		const { wrapper, fetchMock } = await mountResetRequest({
			'POST /v1/auth/password-reset': () => mockResponse(200),
		})

		await fillAndSubmit(wrapper, 'marta@renew.example')

		expect(fetchMock).toHaveBeenCalledWith(
			'/v1/auth/password-reset',
			expect.objectContaining({
				method: 'POST',
				body: JSON.stringify({ email: 'marta@renew.example' }),
			}),
		)

		expect(wrapper.find('form').exists()).toBe(false)
		expect(wrapper.text()).toContain('Check your email')
		expect(wrapper.text()).toContain(
			'If an account exists for that email, a password reset link has been sent.',
		)
		expect(wrapper.text()).toContain('The link expires in 1 hour.')

		const resultPanel = wrapper.findComponent(ResultPanel)
		expect(resultPanel.props('tone')).toBe('success')
		expect(resultPanel.props('icon')).toBe('i-lucide-mail-check')

		const action = wrapper.find('button')
		expect(action.text()).toBe('Back to log in')
		await action.trigger('click')

		await vi.waitFor(() => expect(router.currentRoute.value.path).toBe('/login'))
	})
})

describe('Too many attempts — the button is disabled with a live countdown', () => {
	it('counts down from the Retry-After value and re-enables at zero', async () => {
		vi.useFakeTimers()
		const { wrapper } = await mountResetRequest({
			'POST /v1/auth/password-reset': () => mockResponse(429, null, { 'Retry-After': '58' }),
		})

		await fillAndSubmit(wrapper, 'marta@renew.example')

		expect(wrapper.text()).toContain('Too many requests')
		expect(wrapper.text()).toContain('Wait a moment before asking for another link.')

		expect((emailInput(wrapper).element as HTMLInputElement).value).toBe('marta@renew.example')

		const button = wrapper.find('button[type="submit"]')
		expect(button.text()).toBe('Try again in 0:58')
		expect((button.element as HTMLButtonElement).disabled).toBe(true)
		expect((emailInput(wrapper).element as HTMLInputElement).disabled).toBe(true)

		await vi.advanceTimersByTimeAsync(58000)
		await flushPromises()

		expect(wrapper.find('button[type="submit"]').text()).toBe('Send reset link')
		expect((wrapper.find('button[type="submit"]').element as HTMLButtonElement).disabled).toBe(
			false,
		)
		expect((emailInput(wrapper).element as HTMLInputElement).disabled).toBe(false)
		vi.useRealTimers()
	})
})

describe('Server or network error — the field keeps its value and re-enables', () => {
	it.each([
		{ name: 'a 500 response', handler: () => mockResponse(500) },
		{
			name: 'a network failure',
			handler: () => Promise.reject(new TypeError('Failed to fetch')),
		},
	])('shows the error alert and keeps the value for $name', async ({ handler }) => {
		const request = vi.fn(handler)
		const { wrapper } = await mountResetRequest({
			'POST /v1/auth/password-reset': request,
		})

		await fillAndSubmit(wrapper, 'marta@renew.example')

		expect(request).toHaveBeenCalled()
		expect(wrapper.text()).toContain("Couldn't send the link")
		expect(wrapper.text()).toContain('Check your connection and try again.')

		expect((emailInput(wrapper).element as HTMLInputElement).value).toBe('marta@renew.example')
		expect((emailInput(wrapper).element as HTMLInputElement).disabled).toBe(false)

		const submitButton = wrapper.find('button[type="submit"]')
		expect(submitButton.text()).toBe('Send reset link')
		expect((submitButton.element as HTMLButtonElement).disabled).toBe(false)
	})
})