"use client";

import type { LucideIcon } from "lucide-react";
import { Code2, Database, ExternalLink, File, FileText, Globe, Newspaper } from "lucide-react";
import NextImage from "next/image";
import * as React from "react";
import { openSafeNavigationHref, sanitizeHref } from "../shared/media";
import { cn, Popover, PopoverContent, PopoverTrigger } from "./_adapter";
import type { CitationType, CitationVariant, SerializableCitation } from "./schema";

const FALLBACK_LOCALE = "en-US";

const TYPE_ICONS: Record<CitationType, LucideIcon> = {
	webpage: Globe,
	document: FileText,
	article: Newspaper,
	api: Database,
	code: Code2,
	other: File,
};

function extractDomain(url: string): string | undefined {
	try {
		const urlObj = new URL(url);
		return urlObj.hostname.replace(/^www\./, "");
	} catch {
		return undefined;
	}
}

function formatDate(isoString: string, locale: string): string {
	try {
		const date = new Date(isoString);
		return date.toLocaleDateString(locale, {
			year: "numeric",
			month: "short",
		});
	} catch {
		return isoString;
	}
}

function useHoverPopover(delay = 100) {
	const [open, setOpen] = React.useState(false);
	const timeoutRef = React.useRef<ReturnType<typeof setTimeout> | null>(null);

	const handleMouseEnter = React.useCallback(() => {
		if (timeoutRef.current) clearTimeout(timeoutRef.current);
		timeoutRef.current = setTimeout(() => setOpen(true), delay);
	}, [delay]);

	const handleMouseLeave = React.useCallback(() => {
		if (timeoutRef.current) clearTimeout(timeoutRef.current);
		timeoutRef.current = setTimeout(() => setOpen(false), delay);
	}, [delay]);

	React.useEffect(() => {
		return () => {
			if (timeoutRef.current) clearTimeout(timeoutRef.current);
		};
	}, []);

	return { open, setOpen, handleMouseEnter, handleMouseLeave };
}

export interface CitationProps extends SerializableCitation {
	variant?: CitationVariant;
	className?: string;
	onNavigate?: (href: string, citation: SerializableCitation) => void;
}

export function Citation(props: CitationProps) {
	const { variant = "default", className, onNavigate, ...serializable } = props;

	const {
		id,
		href: rawHref,
		title,
		snippet,
		domain: providedDomain,
		favicon,
		author,
		publishedAt,
		type = "webpage",
		locale: providedLocale,
	} = serializable;

	const locale = providedLocale ?? FALLBACK_LOCALE;
	const sanitizedHref = sanitizeHref(rawHref);
	const domain = providedDomain ?? extractDomain(rawHref);

	const citationData: SerializableCitation = {
		...serializable,
		href: sanitizedHref ?? rawHref,
		domain,
		locale,
	};

	const TypeIcon = TYPE_ICONS[type] ?? Globe;

	const handleClick = () => {
		if (!sanitizedHref) return;
		if (onNavigate) {
			onNavigate(sanitizedHref, citationData);
		} else {
			openSafeNavigationHref(sanitizedHref);
		}
	};

	const handleKeyDown = (e: React.KeyboardEvent) => {
		if (sanitizedHref && (e.key === "Enter" || e.key === " ")) {
			e.preventDefault();
			handleClick();
		}
	};

	const iconElement = favicon ? (
		<NextImage
			src={favicon}
			alt=""
			aria-hidden="true"
			width={16}
			height={16}
			className="bg-muted size-3.5 shrink-0 rounded object-cover"
			unoptimized={true}
		/>
	) : (
		<TypeIcon className="size-3.5 shrink-0 opacity-60" aria-hidden="true" />
	);

	const { open, handleMouseEnter, handleMouseLeave } = useHoverPopover();

	// Inline variant: compact chip with hover popover
	if (variant === "inline") {
		return (
			<Popover open={open}>
				<PopoverTrigger asChild>
					<button
						type="button"
						aria-label={title}
						data-tool-ui-id={id}
						data-slot="citation"
						onClick={handleClick}
						onMouseEnter={handleMouseEnter}
						onMouseLeave={handleMouseLeave}
						className={cn(
							"inline-flex cursor-pointer items-center gap-1.5 rounded-md px-2 py-1",
							"bg-muted/60 text-sm outline-none",
							"transition-colors duration-150",
							"hover:bg-muted",
							"focus-visible:ring-ring focus-visible:ring-2",
							className
						)}
					>
						{iconElement}
						<span className="text-muted-foreground">{domain}</span>
					</button>
				</PopoverTrigger>
				<PopoverContent
					side="top"
					align="start"
					className="w-72 cursor-pointer p-0"
					onMouseEnter={handleMouseEnter}
					onMouseLeave={handleMouseLeave}
					onOpenAutoFocus={(e) => e.preventDefault()}
					onCloseAutoFocus={(e) => e.preventDefault()}
					onClick={handleClick}
				>
					<div className="hover:bg-muted/50 flex flex-col gap-2 p-3 transition-colors">
						<div className="flex items-start gap-2">
							{iconElement}
							<span className="text-muted-foreground text-xs">{domain}</span>
						</div>
						<p className="text-sm leading-snug font-medium">{title}</p>
						{snippet && (
							<p className="text-muted-foreground line-clamp-2 text-xs leading-relaxed">
								{snippet}
							</p>
						)}
					</div>
				</PopoverContent>
			</Popover>
		);
	}

	// Default variant: full card
	return (
		<article
			className={cn("relative w-full max-w-md min-w-72", className)}
			lang={locale}
			data-tool-ui-id={id}
			data-slot="citation"
		>
			{/* biome-ignore lint/a11y/noStaticElementInteractions: div receives role="link" conditionally when href is present */}
			<div
				className={cn(
					"group @container relative isolate flex w-full min-w-0 flex-col overflow-hidden rounded-xl",
					"border-border bg-card border text-sm shadow-xs",
					"transition-colors duration-150",
					sanitizedHref && [
						"cursor-pointer",
						"hover:border-foreground/25",
						"focus-visible:ring-ring focus-visible:ring-2 focus-visible:ring-offset-2 focus-visible:outline-none",
					]
				)}
				onClick={sanitizedHref ? handleClick : undefined}
				role={sanitizedHref ? "link" : undefined}
				tabIndex={sanitizedHref ? 0 : undefined}
				onKeyDown={sanitizedHref ? handleKeyDown : undefined}
			>
				<div className="flex flex-col gap-2 p-4">
					<div className="text-muted-foreground flex min-w-0 items-center justify-between gap-1.5 text-xs">
						<div className="flex min-w-0 items-center gap-1.5">
							{iconElement}
							<span className="truncate font-medium">{domain}</span>
							{(author || publishedAt) && (
								<span className="opacity-70">
									<span className="opacity-60"> — </span>
									{author}
									{author && publishedAt && ", "}
									{publishedAt && (
										<time dateTime={publishedAt} className="tabular-nums">
											{formatDate(publishedAt, locale)}
										</time>
									)}
								</span>
							)}
						</div>
						{sanitizedHref && (
							<ExternalLink className="size-3.5 shrink-0 opacity-0 transition-opacity group-hover:opacity-100" />
						)}
					</div>

					<h3 className="text-foreground text-[15px] leading-snug font-medium text-pretty">
						<span className="group-hover:decoration-foreground/30 line-clamp-2 group-hover:underline group-hover:underline-offset-2">
							{title}
						</span>
					</h3>

					{snippet && (
						<p className="text-muted-foreground text-[13px] leading-relaxed text-pretty">
							<span className="line-clamp-3">{snippet}</span>
						</p>
					)}
				</div>
			</div>
		</article>
	);
}