let isMac: boolean | undefined

interface Navigator {
	userAgentData?: {
		brands: { brand: string; version: string }[]
		mobile: boolean
		platform: string
		getHighEntropyValues: (hints: string[]) => Promise<{
			platform: string
			platformVersion: string
			uaFullVersion: string
		}>
	}
}

function getPlatform(): string {
	const nav = navigator as Navigator

	if (nav.userAgentData) {
		if (nav.userAgentData.platform) {
			return nav.userAgentData.platform
		}

		nav.userAgentData.getHighEntropyValues(["platform"]).then(highEntropyValues => {
			if (highEntropyValues.platform) {
				return highEntropyValues.platform
			}
		})
	}

	if (typeof navigator.platform === "string") {
		return navigator.platform
	}

	return ""
}

export function isMacOS() {
	if (isMac === undefined) {
		isMac = getPlatform().toLowerCase().includes("mac")
	}

	return isMac
}

interface ShortcutKeyResult {
	symbol: string
	readable: string
}

export function getShortcutKey(key: string): ShortcutKeyResult {
	const lowercaseKey = key.toLowerCase()
	if (lowercaseKey === "mod") {
		return isMacOS() ? { symbol: "⌘", readable: "Command" } : { symbol: "Ctrl", readable: "Control" }
	} else if (lowercaseKey === "alt") {
		return isMacOS() ? { symbol: "⌥", readable: "Option" } : { symbol: "Alt", readable: "Alt" }
	} else if (lowercaseKey === "shift") {
		return isMacOS() ? { symbol: "⇧", readable: "Shift" } : { symbol: "Shift", readable: "Shift" }
	} else {
		return { symbol: key.toUpperCase(), readable: key }
	}
}

export function getShortcutKeys(keys: string[]): ShortcutKeyResult[] {
	return keys.map(key => getShortcutKey(key))
}