import {
	useFetcher,
	useLocation,
	useNavigate,
} from "react-router"
import { useEffect, useState } from "react"
import { average } from "color.js"
import { imageUrl, type PaginatedResponse } from "api/api"
import PeriodSelector from "~/components/PeriodSelector"

interface ChartLayoutProps<T> {
	title: "Top Albums" | "Top Tracks" | "Top Artists" | "Last Played"
	initialData: PaginatedResponse<T>
	endpoint: string
	render: (opts: {
		data: PaginatedResponse<T>
		page: number
		onNext: () => void
		onPrev: () => void
	}) => React.ReactNode
}

export default function ChartLayout<T>({
	title,
	initialData,
	endpoint,
	render,
}: ChartLayoutProps<T>) {
	const pgTitle = `${title} - Koito`

	const fetcher = useFetcher()
	const location = useLocation()
	const navigate = useNavigate()

	const currentParams = new URLSearchParams(location.search)
	const currentPage = parseInt(currentParams.get("page") || "1", 10)

	const data: PaginatedResponse<T> = fetcher.data?.[endpoint]
		? fetcher.data[endpoint]
		: initialData

	const [bgColor, setBgColor] = useState<string>("(--color-bg)")

	useEffect(() => {
		if ((data?.items?.length ?? 0) === 0) return

		const img = (data.items[0] as any)?.image
		if (!img) return

		average(imageUrl(img, "small"), { amount: 1 }).then((color) => {
			setBgColor(`rgba(${color[0]},${color[1]},${color[2]},0.4)`)
		})
	}, [data])

	const period = currentParams.get("period") ?? "day"
	const year = currentParams.get("year") 
	const month = currentParams.get("month")
	const week = currentParams.get("week") 

	const updateParams = (params: Record<string, string | null>) => {
        const nextParams = new URLSearchParams(location.search)
    
        for (const key in params) {
            const val = params[key]
            if (val !== null) {
                nextParams.set(key, val)
            } else {
                nextParams.delete(key)
            }
        }
    
        const url = `/${endpoint}?${nextParams.toString()}`
        navigate(url, { replace: false })
    }
    
	const handleSetPeriod = (p: string) => {
		updateParams({
            period: p,
            page: "1",
            year: null,
            month: null,
            week: null,
        })        
	}
	const handleSetYear = (val: string) => {
        if (val == "") {
            updateParams({
                period: period,
                page: "1",
                year: null,
                month: null,
                week: null
            })
            return
        }
		updateParams({
            period: null,
            page: "1",
            year: val,
        })  
	}
	const handleSetMonth = (val: string) => {
		updateParams({
            period: null,
            page: "1",
            year: year ?? new Date().getFullYear().toString(),
            month: val,
        })  
	}
	const handleSetWeek = (val: string) => {
		updateParams({
            period: null,
            page: "1",
            year: year ?? new Date().getFullYear().toString(),
            month: null,
            week: val,
        })  
	}

	useEffect(() => {
		fetcher.load(`/${endpoint}?${currentParams.toString()}`)
	}, [location.search])

	const setPage = (nextPage: number) => {
		const nextParams = new URLSearchParams(location.search)
		nextParams.set("page", String(nextPage))
		const url = `/${endpoint}?${nextParams.toString()}`
		fetcher.load(url)
		navigate(url, { replace: false })
	}

	const handleNextPage = () => setPage(currentPage + 1)
	const handlePrevPage = () => setPage(currentPage - 1)

	const yearOptions = Array.from({ length: 10 }, (_, i) => `${new Date().getFullYear() - i}`)
	const monthOptions = Array.from({ length: 12 }, (_, i) => `${i + 1}`)
	const weekOptions = Array.from({ length: 53 }, (_, i) => `${i + 1}`)

    const getDateRange = (): string => {
        let from: Date
        let to: Date
    
        const now = new Date()
        const currentYear = now.getFullYear()
        const currentMonth = now.getMonth() // 0-indexed
        const currentDate = now.getDate()
    
        if (year && month) {
            from = new Date(parseInt(year), parseInt(month) - 1, 1)
            to = new Date(from)
            to.setMonth(from.getMonth() + 1)
            to.setDate(0)
        } else if (year && week) {
            const base = new Date(parseInt(year), 0, 1) // Jan 1 of the year
            const weekNumber = parseInt(week)
            from = new Date(base)
            from.setDate(base.getDate() + (weekNumber - 1) * 7)
            to = new Date(from)
            to.setDate(from.getDate() + 6)
        } else if (year) {
            from = new Date(parseInt(year), 0, 1)
            to = new Date(parseInt(year), 11, 31)
        } else {
            switch (period) {
                case "day":
                    from = new Date(now)
                    to = new Date(now)
                    break
                case "week":
                    to = new Date(now)
                    from = new Date(now)
                    from.setDate(to.getDate() - 6)
                    break
                case "month":
                    to = new Date(now)
                    from = new Date(now)
                    if (currentMonth === 0) {
                        from = new Date(currentYear - 1, 11, currentDate)
                    } else {
                        from = new Date(currentYear, currentMonth - 1, currentDate)
                    }
                    break
                case "year":
                    to = new Date(now)
                    from = new Date(currentYear - 1, currentMonth, currentDate)
                    break
                case "all_time":
                    return "All Time"
                default:
                    return ""
            }
        }
    
        const formatter = new Intl.DateTimeFormat(undefined, {
            year: "numeric",
            month: "long",
            day: "numeric",
        })
    
        return `${formatter.format(from)} - ${formatter.format(to)}`
    }
    

	return (
		<div
			className="w-full min-h-screen"
			style={{
				background: `linear-gradient(to bottom, ${bgColor}, var(--color-bg) 500px)`,
				transition: "1000",
			}}
		>
			<title>{pgTitle}</title>
			<meta property="og:title" content={pgTitle} />
			<meta name="description" content={pgTitle} />
			<div className="w-19/20 sm:17/20 mx-auto pt-6 sm:pt-12">
				<h1>{title}</h1>
				<div className="flex flex-col items-start md:flex-row sm:items-center gap-4">
					<PeriodSelector current={period} setter={handleSetPeriod} disableCache />
					<div className="flex gap-5">
						<select
							value={year ?? ""}
							onChange={(e) => handleSetYear(e.target.value)}
							className="px-2 py-1 rounded border border-gray-400"
						>
							<option value="">Year</option>
							{yearOptions.map((y) => (
								<option key={y} value={y}>{y}</option>
							))}
						</select>
						<select
							value={month ?? ""}
							onChange={(e) => handleSetMonth(e.target.value)}
							className="px-2 py-1 rounded border border-gray-400"
						>
							<option value="">Month</option>
							{monthOptions.map((m) => (
								<option key={m} value={m}>{m}</option>
							))}
						</select>
						<select
							value={week ?? ""}
							onChange={(e) => handleSetWeek(e.target.value)}
							className="px-2 py-1 rounded border border-gray-400"
						>
							<option value="">Week</option>
							{weekOptions.map((w) => (
								<option key={w} value={w}>{w}</option>
							))}
						</select>
					</div>
				</div>
				<p className="mt-2 text-sm text-color-fg-secondary">{getDateRange()}</p>
				<div className="mt-10 sm:mt-20 flex mx-auto justify-between">
					{render({
						data,
						page: currentPage,
						onNext: handleNextPage,
						onPrev: handlePrevPage,
					})}
				</div>
			</div>
		</div>
	)
}