"use client";

import { useMemo, useState } from "react";
import Link from "@/components/link";
import type {
	CanonicalHousekeepingHref,
	HousekeepingSurface,
	HousekeepingWorkItem,
} from "../contracts";
import type { HousekeepingInboxResponse } from "../inbox/inbox-service";
import { toHousekeepingHref } from "../routing/href";

export interface OperationalInboxLabels {
	readonly title: string;
	readonly domainFilter: string;
	readonly stateFilter: string;
	readonly priorityFilter: string;
	readonly all: string;
	readonly loading: string;
	readonly empty: string;
	readonly partial: string;
	readonly open: string;
}

export interface OperationalInboxFilters {
	readonly domain: string;
	readonly state: string;
	readonly priority: string;
}

export function filterOperationalInboxItems(
	items: readonly HousekeepingWorkItem[],
	filters: OperationalInboxFilters,
): readonly HousekeepingWorkItem[] {
	return items.filter(
		(item) =>
			(filters.domain === "all" || item.domain === filters.domain) &&
			(filters.state === "all" || item.state === filters.state) &&
			(filters.priority === "all" || item.priority === filters.priority),
	);
}

export function projectOperationalInboxHref(
	href: CanonicalHousekeepingHref,
	surface: HousekeepingSurface,
) {
	return toHousekeepingHref(href, surface);
}

function unique(values: readonly string[]): readonly string[] {
	return [...new Set(values)].sort((left, right) => left.localeCompare(right));
}

export function OperationalInbox({
	response,
	labels,
	surface,
	loading = false,
	titles = {},
}: {
	readonly response: HousekeepingInboxResponse;
	readonly labels: OperationalInboxLabels;
	readonly surface: HousekeepingSurface;
	readonly loading?: boolean;
	readonly titles?: Readonly<Record<string, string>>;
}) {
	const [domain, setDomain] = useState("all");
	const [state, setState] = useState("all");
	const [priority, setPriority] = useState("all");
	const domains = useMemo(
		() => unique(response.items.map((item) => item.domain)),
		[response.items],
	);
	const states = useMemo(
		() => unique(response.items.map((item) => item.state)),
		[response.items],
	);
	const priorities = useMemo(
		() => unique(response.items.map((item) => item.priority)),
		[response.items],
	);
	const items = useMemo(
		() =>
			filterOperationalInboxItems(response.items, {
				domain,
				state,
				priority,
			}),
		[domain, priority, response.items, state],
	);

	return (
		<section
			aria-labelledby="operational-inbox-title"
			className="min-w-0 space-y-4"
		>
			<h2 id="operational-inbox-title" className="text-lg font-semibold">
				{labels.title}
			</h2>
			{loading ? <p role="status">{labels.loading}</p> : null}
			{!loading ? (
				<>
					<div className="grid gap-3 sm:grid-cols-3">
						<select
							aria-label={labels.domainFilter}
							value={domain}
							onChange={(event) => setDomain(event.target.value)}
							className="min-w-0 rounded-md border border-[var(--admin-border)] bg-[var(--admin-surface)] px-3 py-2 focus-visible:outline focus-visible:outline-2 focus-visible:outline-offset-2 focus-visible:outline-[var(--admin-accent)]"
						>
							<option value="all">{labels.all}</option>
							{domains.map((value) => (
								<option key={value} value={value}>
									{value}
								</option>
							))}
						</select>
						<select
							aria-label={labels.stateFilter}
							value={state}
							onChange={(event) => setState(event.target.value)}
							className="min-w-0 rounded-md border border-[var(--admin-border)] bg-[var(--admin-surface)] px-3 py-2 focus-visible:outline focus-visible:outline-2 focus-visible:outline-offset-2 focus-visible:outline-[var(--admin-accent)]"
						>
							<option value="all">{labels.all}</option>
							{states.map((value) => (
								<option key={value} value={value}>
									{value}
								</option>
							))}
						</select>
						<select
							aria-label={labels.priorityFilter}
							value={priority}
							onChange={(event) => setPriority(event.target.value)}
							className="min-w-0 rounded-md border border-[var(--admin-border)] bg-[var(--admin-surface)] px-3 py-2 focus-visible:outline focus-visible:outline-2 focus-visible:outline-offset-2 focus-visible:outline-[var(--admin-accent)]"
						>
							<option value="all">{labels.all}</option>
							{priorities.map((value) => (
								<option key={value} value={value}>
									{value}
								</option>
							))}
						</select>
					</div>

					{response.errors.length > 0 ? (
						<div
							role="alert"
							aria-live="assertive"
							className="rounded-md border border-[var(--admin-warning-border)] bg-[var(--admin-warning-subtle)] p-3"
						>
							<p className="text-[var(--admin-warning)]">{labels.partial}</p>
						</div>
					) : null}

					{items.length === 0 ? <p>{labels.empty}</p> : null}
					<ul className="space-y-3">
						{items.map((item) => (
							<li
								key={`${item.sourceId}:${item.itemId}`}
								className="min-w-0 rounded-md border border-[var(--admin-border)] bg-[var(--admin-surface)] p-4"
							>
								<div className="flex flex-wrap items-start justify-between gap-3">
									<div className="min-w-0 break-words">
										<p className="font-medium">
											{titles[item.titleKey] ?? item.titleKey}
										</p>
										<p className="text-sm text-[var(--admin-text-muted)]">
											{item.domain} · {item.state} · {item.priority}
										</p>
										<time dateTime={item.occurredAt} className="text-xs">
											{item.occurredAt}
										</time>
									</div>
									<Link
										href={projectOperationalInboxHref(item.href, surface)}
										className="rounded-md border border-[var(--admin-border)] px-3 py-2 text-sm focus-visible:outline focus-visible:outline-2 focus-visible:outline-offset-2 focus-visible:outline-[var(--admin-accent)]"
									>
										{labels.open}
									</Link>
								</div>
							</li>
						))}
					</ul>
				</>
			) : null}
		</section>
	);
}