import { invoke } from '@tauri-apps/api/core'

import { check_mojang_services } from '@/helpers/auth.js'
import { ensureFallenAuthProxyArgs, removeFallenAuthProxyArgs } from '@/helpers/java-arguments'
import { type AppSettings, get, set } from '@/helpers/settings'

const DEFAULT_RETRIES = 3
const RETRY_DELAY_MS = 1000
const REQUIRED_MOJANG_SERVICES = new Set(['account', 'session', 'services', 'profiles'])

export async function checkMojangAuthServers(retries = DEFAULT_RETRIES): Promise<boolean> {
	for (let attempt = 0; attempt < retries; attempt++) {
		try {
			const statuses = await check_mojang_services()
			const requiredStatuses = statuses.filter((status) =>
				REQUIRED_MOJANG_SERVICES.has(status.service),
			)
			if (requiredStatuses.length > 0 && requiredStatuses.every((status) => status.reachable)) {
				return true
			}
		} catch {
			if (attempt < retries - 1) {
				await new Promise((resolve) => setTimeout(resolve, RETRY_DELAY_MS))
			}
		}
	}
	return false
}

function sameArgs(left: string[], right: string[]) {
	return left.length === right.length && left.every((arg, index) => arg === right[index])
}

export async function setMojangAuthUseMirror(useMirror: boolean, automatic: boolean) {
	await invoke('plugin:auth|set_mojang_auth_use_mirror', { useMirror, automatic })
}

export async function reconcileMojangAuthSource(settings: AppSettings): Promise<boolean> {
	const mode = settings.mojang_auth_source ?? 'auto'
	const automatic = mode === 'auto' || mode === 'official_preferred'
	let useMirror: boolean
	if (mode === 'mirror_preferred') {
		useMirror = true
	} else if (mode === 'official_only') {
		useMirror = false
	} else {
		// Automatic and official-preferred check the services used by current
		// Minecraft versions, falling back only when one of them is down.
		useMirror = !(await checkMojangAuthServers())
	}

	await setMojangAuthUseMirror(useMirror, automatic)

	const nextArgs = useMirror
		? ensureFallenAuthProxyArgs(settings.extra_launch_args)
		: removeFallenAuthProxyArgs(settings.extra_launch_args)

	if (sameArgs(nextArgs, settings.extra_launch_args)) return false

	settings.extra_launch_args = nextArgs
	return true
}

export async function reconcileMojangAuthSourceAtStartup(): Promise<void> {
	const settings = await get()
	if (await reconcileMojangAuthSource(settings)) {
		await set(settings)
	}
}