"use client"

import { useRouter } from "next/navigation"
import { useEffect, useMemo, useState, useRef } from "react"
import { ArrowUpIcon, ArrowDownIcon, CornerDownLeftIcon, FileTextIcon } from "lucide-react"
import Anchor from "./anchor"
import { cn } from "@/lib/utils"
import { advanceSearch } from "@/lib/search/built-in"
import { ScrollArea } from "@/components/ui/scroll-area"
import { page_routes } from "@/lib/routes"
import {
  DialogContent,
  DialogHeader,
  DialogFooter,
  DialogClose,
  DialogTitle,
  DialogDescription,
} from "@/components/ui/dialog"

type ContextInfo = {
  icon: string
  description: string
  title?: string
}

type SearchResult = {
  title: string
  href: string
  noLink?: boolean
  items?: undefined
  score?: number
  context?: ContextInfo
}

const paddingMap = {
  1: "pl-2",
  2: "pl-4",
  3: "pl-10",
} as const

interface SearchModalProps {
  isOpen: boolean
  setIsOpen: (open: boolean) => void
}

export function SearchModal({ isOpen, setIsOpen }: SearchModalProps) {
  const router = useRouter()
  const [searchedInput, setSearchedInput] = useState("")
  const [selectedIndex, setSelectedIndex] = useState(0)
  const itemRefs = useRef<(HTMLDivElement | null)[]>([])

  useEffect(() => {
    if (!isOpen) {
      // eslint-disable-next-line react-hooks/set-state-in-effect
      setSearchedInput("")
    }
  }, [isOpen])

  const filteredResults = useMemo<SearchResult[]>(() => {
    const trimmedInput = searchedInput.trim()

    if (trimmedInput.length < 3) {
      return page_routes
        .filter((route) => !route.href.endsWith("/"))
        .slice(0, 6)
        .map((route: { title: string; href: string; noLink?: boolean; context?: ContextInfo }) => ({
          title: route.title,
          href: route.href,
          noLink: route.noLink,
          context: route.context,
        }))
    }
    return advanceSearch(trimmedInput) as unknown as SearchResult[]
  }, [searchedInput])

  // useEffect(() => {
  //   setSelectedIndex(0);
  // }, [filteredResults]);

  useEffect(() => {
    const handleNavigation = (event: KeyboardEvent) => {
      if (!isOpen || filteredResults.length === 0) return

      if (event.key === "ArrowDown") {
        event.preventDefault()
        setSelectedIndex((prev) => (prev + 1) % filteredResults.length)
      } else if (event.key === "ArrowUp") {
        event.preventDefault()
        setSelectedIndex((prev) => (prev - 1 + filteredResults.length) % filteredResults.length)
      } else if (event.key === "Enter") {
        event.preventDefault()
        const selectedItem = filteredResults[selectedIndex]
        if (selectedItem) {
          router.push(`/docs${selectedItem.href}`)
          setIsOpen(false)
        }
      }
    }

    window.addEventListener("keydown", handleNavigation)
    return () => window.removeEventListener("keydown", handleNavigation)
  }, [isOpen, filteredResults, selectedIndex, router, setIsOpen])

  useEffect(() => {
    if (itemRefs.current[selectedIndex]) {
      itemRefs.current[selectedIndex]?.scrollIntoView({
        behavior: "smooth",
        block: "nearest",
      })
    }
  }, [selectedIndex])

  return (
    <DialogContent className="rounded-md! top-[45%] max-w-[650px] p-0 sm:top-[38%]">
      <DialogHeader>
        <DialogTitle className="sr-only">Search Documentation</DialogTitle>
        <DialogDescription className="sr-only">Search through the documentation</DialogDescription>
      </DialogHeader>

      <input
        value={searchedInput}
        onChange={(e) => {
          setSearchedInput(e.target.value)
          setSelectedIndex(0)
        }}
        placeholder="Type something to search..."
        autoFocus
        className="h-14 w-full border-b bg-transparent px-6 text-[14px] outline-none"
        aria-label="Search documentation"
      />

      {filteredResults.length == 0 && searchedInput && (
        <p className="text-muted-foreground mx-auto mt-2 text-sm">
          No results found for <span className="text-primary">{`"${searchedInput}"`}</span>
        </p>
      )}
      <ScrollArea className="max-h-[400px] overflow-y-auto">
        <div className="flex flex-col items-start overflow-y-auto px-1 pb-4 sm:px-2">
          {filteredResults.map((item, index) => {
            const level = (item.href.split("/").slice(1).length - 1) as keyof typeof paddingMap
            const paddingClass = paddingMap[level] || "pl-2"
            const isActive = index === selectedIndex

            return (
              <DialogClose key={item.href} asChild>
                <Anchor
                  ref={(el) => {
                    itemRefs.current[index] = el as HTMLDivElement | null
                  }}
                  className={cn(
                    "dark:hover:bg-accent/15 hover:bg-accent/10 flex w-full items-center gap-2.5 rounded-sm px-3 text-sm",
                    isActive && "bg-primary/20 dark:bg-primary/30",
                    paddingClass
                  )}
                  href={`/docs${item.href}`}
                  tabIndex={-1}
                >
                  <div
                    className={cn(
                      "flex h-full w-full items-center justify-between gap-1.5 px-2 py-3",
                      level > 1 && "border-l pl-4"
                    )}
                  >
                    <div className="flex items-center">
                      <FileTextIcon className="mr-1 h-[1.1rem] w-[1.1rem]" />
                      <span>{item.title}</span>
                    </div>
                    {isActive && (
                      <div className="text-muted-foreground hidden items-center text-xs md:flex">
                        <span>Return</span>
                        <CornerDownLeftIcon className="ml-1 h-3 w-3" />
                      </div>
                    )}
                  </div>
                </Anchor>
              </DialogClose>
            )
          })}
        </div>
      </ScrollArea>
      <DialogFooter className="hidden h-14 border-t bg-transparent px-6 text-[14px] outline-none md:flex md:justify-start">
        <div className="flex items-center gap-2">
          <span className="dark:bg-accent/15 rounded border bg-slate-200 p-2">
            <ArrowUpIcon className="h-3 w-3" />
          </span>
          <span className="dark:bg-accent/15 rounded border bg-slate-200 p-2">
            <ArrowDownIcon className="h-3 w-3" />
          </span>
          <p className="text-muted-foreground">to navigate</p>
          <span className="dark:bg-accent/15 rounded border bg-slate-200 p-2">
            <CornerDownLeftIcon className="h-3 w-3" />
          </span>
          <p className="text-muted-foreground">to select</p>
          <span className="dark:bg-accent/15 rounded border bg-slate-200 px-2 py-1">esc</span>
          <p className="text-muted-foreground">to close</p>
        </div>
      </DialogFooter>
    </DialogContent>
  )
}