import { expect, test, vi } from 'vitest'

import { observe } from './observe.js'
import { wait } from './wait.js'

test('emits data to callbacks', async () => {
	const id = 'mock'
	const callback1 = vi.fn()
	const callback2 = vi.fn()
	const callback3 = vi.fn()

	const emitter = vi.fn(({ emit }) => {
		setTimeout(() => emit({ foo: 'bar' }), 100)
		return () => {
			//
		}
	})

	const unwatch1 = observe(id, { emit: callback1 }, emitter)
	const unwatch2 = observe(id, { emit: callback2 }, emitter)
	const unwatch3 = observe(id, { emit: callback3 }, emitter)

	await wait(100)

	expect(emitter).toHaveBeenCalledOnce()
	expect(callback1).toHaveBeenNthCalledWith(1, { foo: 'bar' })
	expect(callback2).toHaveBeenNthCalledWith(1, { foo: 'bar' })
	expect(callback3).toHaveBeenNthCalledWith(1, { foo: 'bar' })

	unwatch1()
	unwatch2()
	unwatch3()
})

test('scopes to id', async () => {
	const id1 = 'mock'
	const callback1 = vi.fn()
	const emitter1 = vi.fn(({ emit }) => {
		setTimeout(() => emit({ foo: 'bar1' }), 100)
		return () => {
			//
		}
	})
	const unwatch1 = observe(id1, { emit: callback1 }, emitter1)

	const id2 = 'mock2'
	const callback2 = vi.fn()
	const emitter2 = vi.fn(({ emit }) => {
		setTimeout(() => emit({ foo: 'bar2' }), 100)
		return () => {
			//
		}
	})
	const unwatch2 = observe(id2, { emit: callback2 }, emitter2)

	await wait(100)

	expect(emitter1).toHaveBeenCalledTimes(1)
	expect(emitter2).toHaveBeenCalledTimes(1)
	expect(callback1).toHaveBeenNthCalledWith(1, { foo: 'bar1' })
	expect(callback2).toHaveBeenNthCalledWith(1, { foo: 'bar2' })

	unwatch1()
	unwatch2()
})

test('cleans up listeners correctly (staggered unwatch)', async () => {
	const id = 'mock'
	const callback1 = vi.fn()
	const callback2 = vi.fn()
	const callback3 = vi.fn()

	const emitter = vi.fn(({ emit }) => {
		setTimeout(() => emit({ foo: 'bar' }), 100)
		setTimeout(() => emit({ foo: 'bar' }), 200)
		setTimeout(() => emit({ foo: 'bar' }), 300)
		return () => {
			//
		}
	})

	const unwatch1 = observe(id, { emit: callback1 }, emitter)
	const unwatch2 = observe(id, { emit: callback2 }, emitter)
	const unwatch3 = observe(id, { emit: callback3 }, emitter)

	unwatch1()

	expect(emitter).toHaveBeenCalledOnce()

	await wait(100)

	expect(emitter).toHaveBeenCalledOnce()
	expect(callback1).toHaveBeenCalledTimes(0)
	expect(callback2).toHaveBeenCalledTimes(1)

	unwatch2()

	await wait(100)

	expect(emitter).toHaveBeenCalledOnce()
	expect(callback3).toHaveBeenCalledTimes(2)

	unwatch3()
})

test('cleans up listeners correctly (immediately unwatch)', async () => {
	const id = 'mock'
	const callback1 = vi.fn()
	const callback2 = vi.fn()
	const callback3 = vi.fn()

	const emitter = vi.fn(({ emit }) => {
		setTimeout(() => emit({ foo: 'bar' }), 100)
		setTimeout(() => emit({ foo: 'bar' }), 200)
		return () => {
			//
		}
	})

	const unwatch1 = observe(id, { emit: callback1 }, emitter)
	const unwatch2 = observe(id, { emit: callback2 }, emitter)
	const unwatch3 = observe(id, { emit: callback3 }, emitter)

	unwatch1()
	unwatch2()
	unwatch3()

	await wait(300)

	expect(emitter).toHaveBeenCalledOnce()
	expect(callback1).toHaveBeenCalledTimes(0)
	expect(callback2).toHaveBeenCalledTimes(0)
	expect(callback3).toHaveBeenCalledTimes(0)
})

test('cleans up emit function correctly', async () => {
	const id = 'mock'
	const callback = vi.fn()

	let active = true
	const emitter = vi.fn(({ emit }) => {
		setTimeout(() => emit({ foo: 'bar' }), 100)
		setTimeout(() => emit({ foo: 'bar' }), 200)
		setTimeout(() => emit({ foo: 'bar' }), 300)
		return () => {
			active = false
		}
	})

	const unwatch1 = observe(id, { emit: callback }, emitter)
	const unwatch2 = observe(id, { emit: callback }, emitter)
	const unwatch3 = observe(id, { emit: callback }, emitter)

	await wait(100)
	expect(emitter).toHaveBeenCalledTimes(1)
	expect(callback).toHaveBeenNthCalledWith(1, { foo: 'bar' })
	expect(active).toBe(true)

	unwatch1()

	await wait(100)
	expect(emitter).toHaveBeenCalledTimes(1)
	expect(callback).toHaveBeenNthCalledWith(1, { foo: 'bar' })
	expect(active).toBe(true)

	unwatch2()

	await wait(100)
	expect(emitter).toHaveBeenCalledTimes(1)
	expect(callback).toHaveBeenNthCalledWith(1, { foo: 'bar' })
	expect(active).toBe(true)

	unwatch3()

	expect(active).toBe(false)
})