import { type ClassValue, clsx } from 'clsx'
import { twMerge } from 'tailwind-merge'
import { cubicOut } from 'svelte/easing'
import type { TransitionConfig } from 'svelte/transition'

export function cn(...inputs: ClassValue[]) {
	return twMerge(clsx(inputs))
}

type FlyAndScaleParams = {
	y?: number
	x?: number
	start?: number
	duration?: number
}

export const flyAndScale = (
	node: Element,
	params: FlyAndScaleParams = {
		y: -8,
		x: 0,
		start: 0.95,
		duration: 150,
	},
): TransitionConfig => {
	const style = getComputedStyle(node)
	const transform = style.transform === 'none' ? '' : style.transform

	const scaleConversion = (
		valueA: number,
		scaleA: [number, number],
		scaleB: [number, number],
	) => {
		const [minA, maxA] = scaleA
		const [minB, maxB] = scaleB

		const percentage = (valueA - minA) / (maxA - minA)
		const valueB = percentage * (maxB - minB) + minB

		return valueB
	}

	const styleToString = (
		style: Record<string, number | string | undefined>,
	): string => {
		return Object.keys(style).reduce((str, key) => {
			if (style[key] === undefined) return str
			return str + `${key}:${style[key]};`
		}, '')
	}

	return {
		duration: params.duration ?? 200,
		delay: 0,
		css: (t) => {
			const y = scaleConversion(t, [0, 1], [params.y ?? 5, 0])
			const x = scaleConversion(t, [0, 1], [params.x ?? 0, 0])
			const scale = scaleConversion(
				t,
				[0, 1],
				[params.start ?? 0.95, 1],
			)

			return styleToString({
				transform: `${transform} translate3d(${x}px, ${y}px, 0) scale(${scale})`,
				opacity: t,
			})
		},
		easing: cubicOut,
	}
}