"use client";

import { useQuery, useQueryClient } from "@tanstack/react-query";
import { useAtomValue } from "jotai";
import { ArrowUp, ChevronDown, ClipboardCopy, Download, Info, Pen } from "lucide-react";
import { useEffect, useRef, useState } from "react";
import { toast } from "sonner";
import { z } from "zod";
import { updateSearchSpaceMutationAtom } from "@/atoms/search-spaces/search-space-mutation.atoms";
import { PlateEditor } from "@/components/editor/plate-editor";
import { Alert, AlertDescription } from "@/components/ui/alert";
import { Button } from "@/components/ui/button";
import {
	DropdownMenu,
	DropdownMenuContent,
	DropdownMenuItem,
	DropdownMenuTrigger,
} from "@/components/ui/dropdown-menu";
import { Spinner } from "@/components/ui/spinner";
import { baseApiService } from "@/lib/apis/base-api.service";
import { searchSpacesApiService } from "@/lib/apis/search-spaces-api.service";
import { cacheKeys } from "@/lib/query-client/cache-keys";

const MEMORY_HARD_LIMIT = 25_000;

const SearchSpaceSchema = z
	.object({
		shared_memory_md: z.string().optional().default(""),
	})
	.passthrough();

interface TeamMemoryManagerProps {
	searchSpaceId: number;
}

export function TeamMemoryManager({ searchSpaceId }: TeamMemoryManagerProps) {
	const queryClient = useQueryClient();
	const { data: searchSpace, isLoading: loading } = useQuery({
		queryKey: cacheKeys.searchSpaces.detail(searchSpaceId.toString()),
		queryFn: () => searchSpacesApiService.getSearchSpace({ id: searchSpaceId }),
		enabled: !!searchSpaceId,
	});

	const { mutateAsync: updateSearchSpace } = useAtomValue(updateSearchSpaceMutationAtom);

	const [saving, setSaving] = useState(false);
	const [editQuery, setEditQuery] = useState("");
	const [editing, setEditing] = useState(false);
	const [showInput, setShowInput] = useState(false);
	const textareaRef = useRef<HTMLInputElement>(null);
	const inputContainerRef = useRef<HTMLDivElement>(null);

	const memory = searchSpace?.shared_memory_md || "";

	useEffect(() => {
		if (!showInput) return;

		const handlePointerDownOutside = (event: MouseEvent | TouchEvent) => {
			const target = event.target;
			if (!(target instanceof Node)) return;
			if (inputContainerRef.current?.contains(target)) return;

			setShowInput(false);
		};

		document.addEventListener("mousedown", handlePointerDownOutside);
		document.addEventListener("touchstart", handlePointerDownOutside, { passive: true });

		return () => {
			document.removeEventListener("mousedown", handlePointerDownOutside);
			document.removeEventListener("touchstart", handlePointerDownOutside);
		};
	}, [showInput]);

	const handleClear = async () => {
		try {
			setSaving(true);
			await updateSearchSpace({
				id: searchSpaceId,
				data: { shared_memory_md: "" },
			});
			toast.success("Team memory cleared");
		} catch {
			toast.error("Failed to clear team memory");
		} finally {
			setSaving(false);
		}
	};

	const handleEdit = async () => {
		const query = editQuery.trim();
		if (!query) return;

		try {
			setEditing(true);
			await baseApiService.post(
				`/api/v1/searchspaces/${searchSpaceId}/memory/edit`,
				SearchSpaceSchema,
				{ body: { query } }
			);
			setEditQuery("");
			setShowInput(false);
			await queryClient.invalidateQueries({
				queryKey: cacheKeys.searchSpaces.detail(searchSpaceId.toString()),
			});
			toast.success("Team memory updated");
		} catch {
			toast.error("Failed to edit team memory");
		} finally {
			setEditing(false);
		}
	};

	const openInput = () => {
		setShowInput(true);
		requestAnimationFrame(() => textareaRef.current?.focus());
	};

	const handleDownload = () => {
		if (!memory) return;
		try {
			const blob = new Blob([memory], { type: "text/markdown;charset=utf-8" });
			const url = URL.createObjectURL(blob);
			const a = document.createElement("a");
			a.href = url;
			a.download = "team-memory.md";
			document.body.appendChild(a);
			a.click();
			document.body.removeChild(a);
			URL.revokeObjectURL(url);
		} catch {
			toast.error("Failed to download team memory");
		}
	};

	const handleCopyMarkdown = async () => {
		if (!memory) return;
		try {
			await navigator.clipboard.writeText(memory);
			toast.success("Copied to clipboard");
		} catch {
			toast.error("Failed to copy team memory");
		}
	};

	const handleKeyDown = (e: React.KeyboardEvent<HTMLInputElement>) => {
		if (e.key === "Enter" && !e.shiftKey) {
			e.preventDefault();
			handleEdit();
		}
	};

	const displayMemory = memory.replace(/\(\d{4}-\d{2}-\d{2}\)\s*\[(fact|pref|instr)\]\s*/g, "");
	const charCount = memory.length;

	const getCounterColor = () => {
		if (charCount > MEMORY_HARD_LIMIT) return "text-red-500";
		if (charCount > 15_000) return "text-orange-500";
		if (charCount > 10_000) return "text-yellow-500";
		return "text-muted-foreground";
	};

	if (loading) {
		return (
			<div className="flex items-center justify-center py-12">
				<Spinner size="md" className="text-muted-foreground" />
			</div>
		);
	}

	if (!memory) {
		return (
			<div className="flex flex-col items-center justify-center py-16 text-center">
				<h3 className="text-base font-medium text-foreground">
					What does SurfSense remember about your team?
				</h3>
				<p className="mt-2 max-w-sm text-sm text-muted-foreground">
					Nothing yet. SurfSense picks up on team decisions and conventions as your team chats.
				</p>
			</div>
		);
	}

	return (
		<div className="space-y-4">
			<Alert className="bg-muted/50 py-3 md:py-4">
				<Info className="h-3 w-3 md:h-4 md:w-4 shrink-0" />
				<AlertDescription className="text-xs md:text-sm">
					<p>
						SurfSense uses this shared memory to provide team-wide context across all conversations
						in this search space.
					</p>
				</AlertDescription>
			</Alert>

			<div className="relative h-[380px] rounded-lg border bg-background">
				<div className="h-full overflow-y-auto scrollbar-thin">
					<PlateEditor
						markdown={displayMemory}
						readOnly
						preset="readonly"
						variant="default"
						editorVariant="none"
						className="px-5 py-4 text-sm min-h-full"
					/>
				</div>

				{showInput ? (
					<div className="absolute bottom-3 inset-x-3 z-10">
						<div
							ref={inputContainerRef}
							className="relative flex h-[54px] items-center gap-2 rounded-[9999px] border bg-muted/60 backdrop-blur-sm pl-4 pr-1 shadow-sm"
						>
							<input
								ref={textareaRef}
								type="text"
								value={editQuery}
								onChange={(e) => setEditQuery(e.target.value)}
								onKeyDown={handleKeyDown}
								placeholder="Tell SurfSense what to remember or forget about your team"
								disabled={editing}
								className="flex-1 bg-transparent text-sm outline-none placeholder:text-muted-foreground/70"
							/>
							<Button
								type="button"
								size="icon"
								variant="ghost"
								onClick={handleEdit}
								disabled={editing || !editQuery.trim()}
								className={`h-11 w-11 shrink-0 rounded-full ${
									editing ? "" : "bg-muted-foreground/15 hover:bg-muted-foreground/20"
								}`}
							>
								{editing ? (
									<Spinner size="sm" />
								) : (
									<ArrowUp className="!h-5 !w-5 text-foreground" strokeWidth={2.25} />
								)}
							</Button>
						</div>
					</div>
				) : (
					<Button
						type="button"
						size="icon"
						variant="secondary"
						onClick={openInput}
						className="absolute bottom-3 right-3 z-10 h-[54px] w-[54px] rounded-full border bg-muted/60 backdrop-blur-sm shadow-sm"
					>
						<Pen className="!h-5 !w-5" />
					</Button>
				)}
			</div>

			<div className="flex items-center justify-between gap-2">
				<span className={`text-xs shrink-0 ${getCounterColor()}`}>
					{charCount.toLocaleString()} / {MEMORY_HARD_LIMIT.toLocaleString()}
					<span className="hidden sm:inline"> characters</span>
					<span className="sm:hidden"> chars</span>
					{charCount > 15_000 && charCount <= MEMORY_HARD_LIMIT && " - Approaching limit"}
					{charCount > MEMORY_HARD_LIMIT && " - Exceeds limit"}
				</span>
				<div className="flex items-center gap-1.5 sm:gap-2">
					<Button
						type="button"
						variant="destructive"
						size="sm"
						className="text-xs sm:text-sm"
						onClick={handleClear}
						disabled={saving || editing || !memory}
					>
						<span className="hidden sm:inline">Reset Memory</span>
						<span className="sm:hidden">Reset</span>
					</Button>
					<DropdownMenu>
						<DropdownMenuTrigger asChild>
							<Button type="button" variant="secondary" size="sm" disabled={!memory}>
								Export
								<ChevronDown className="h-3 w-3 opacity-60" />
							</Button>
						</DropdownMenuTrigger>
						<DropdownMenuContent align="end">
							<DropdownMenuItem onClick={handleCopyMarkdown}>
								<ClipboardCopy className="h-4 w-4 mr-2" />
								Copy as Markdown
							</DropdownMenuItem>
							<DropdownMenuItem onClick={handleDownload}>
								<Download className="h-4 w-4 mr-2" />
								Download as Markdown
							</DropdownMenuItem>
						</DropdownMenuContent>
					</DropdownMenu>
				</div>
			</div>
		</div>
	);
}