import os from "node:os";
import { redirect } from "next/navigation";
import { getTranslations } from "next-intl/server";
import {
	DiagnosticRow,
	InfoItem,
	OnlineUsersWidget,
	StatusCard,
} from "@/components/admin/dashboard";
import { formatDate } from "@/lib/format-date";
import { canAccess, getAdminContext, PERMS } from "@/lib/permissions";
import { prisma } from "@/lib/prisma";
import { rcon } from "@/lib/services/rcon";
import { siteSettings } from "@/lib/services/site-settings";
import { CommandocentrumControls } from "./commandocentrum-controls";

export const dynamic = "force-dynamic";

function decodeStacktrace(raw: unknown): string {
	if (raw == null) return "";
	try {
		if (typeof raw === "string") return raw;
		return Buffer.from(raw as Uint8Array).toString("utf8");
	} catch {
		return "";
	}
}

function mb(bytes: number): string {
	return `${Math.round(bytes / 1024 / 1024)} MB`;
}

function uptime(seconds: number): string {
	const d = Math.floor(seconds / 86400);
	const h = Math.floor((seconds % 86400) / 3600);
	const m = Math.floor((seconds % 3600) / 60);
	return d > 0 ? `${d}d ${h}h ${m}m` : h > 0 ? `${h}h ${m}m` : `${m}m`;
}

export default async function CommandoCentrum() {
	const { session, permissions } = await getAdminContext();
	if (!canAccess(permissions, PERMS.RCON_EXECUTE, session.user.rank)) {
		redirect("/admin");
	}

	const t = await getTranslations("pages.admin.commandocentrum");

	const [
		onlineCount,
		totalUsers,
		errors,
		dbOk,
		emulatorOnline,
		maintenance,
		activity,
	] = await Promise.all([
		prisma.user.count({ where: { online: "1" } }).catch(() => 0),
		prisma.user.count().catch(() => -1),
		prisma.emulatorErrors
			.findMany({ orderBy: { timestamp: "desc" }, take: 50 })
			.catch(() => []),
		prisma.websiteSetting
			.count()
			.then(() => true)
			.catch(() => false),
		rcon.send("ping", null).catch(() => false),
		siteSettings.getBool("maintenance_enabled", false),
		prisma.staffActivities
			.findMany({ orderBy: { createdAt: "desc" }, take: 12 })
			.catch(
				() => [] as Awaited<ReturnType<typeof prisma.staffActivities.findMany>>,
			),
	]);

	const staffIds = Array.from(
		new Set(activity.map((a) => Number(a.userId))),
	).filter((n) => n > 0);
	let nameById = new Map<number, string>();
	if (staffIds.length) {
		const users = await prisma.user
			.findMany({
				where: { id: { in: staffIds } },
				select: { id: true, username: true },
			})
			.catch(() => []);
		nameById = new Map(users.map((u) => [u.id, u.username]));
	}

	const appKeySet = !!process.env.APP_KEY;
	const smtpSet = !!process.env.SMTP_HOST;
	const rconSet = !!process.env.RCON_HOST;

	return (
		<main>
			{/* ── Live status ────────────────────────────────────────── */}
			<div
				className="grid grid-cols-[repeat(auto-fit,minmax(180px,1fr))] gap-3.5 mb-6"
				style={{ marginTop: "1.1rem" }}
			>
				<StatusCard
					label={t("playersOnline")}
					value={onlineCount}
					hint={
						totalUsers >= 0
							? t("totalAccounts", { count: totalUsers })
							: t("dbUnavailable")
					}
					state="neutral"
					icon="👤"
				/>
				<StatusCard
					label={t("emulator")}
					value={emulatorOnline ? t("online") : t("offline")}
					hint={emulatorOnline ? t("rconReachable") : t("rconNotResponding")}
					state={emulatorOnline ? "ok" : "danger"}
					icon="🎮"
				/>
				<StatusCard
					label={t("database")}
					value={dbOk ? t("connected") : t("down")}
					hint={dbOk ? t("queriesResponding") : t("cannotReachDb")}
					state={dbOk ? "ok" : "danger"}
					icon="🗄️"
				/>
				<StatusCard
					label={t("emulatorErrors")}
					value={errors.length}
					hint={t("last50Logged")}
					state={errors.length === 0 ? "ok" : "warn"}
					icon="⚠️"
				/>
			</div>

			{/* ── Online users widget ───────────────────────────────── */}
			<section className="admin-card mb-6">
				<h2 className="admin-section-title">{t("onlineUsers")}</h2>
				<OnlineUsersWidget users={[]} isLoading={false} />
			</section>

			{/* ── Server info + diagnostics ──────────────────────────── */}
			<div className="grid grid-cols-1 gap-4 md:grid-cols-2">
				<section className="admin-card p-5">
					<h2 className="admin-section-title">{t("serverInfo")}</h2>
					<div className="grid grid-cols-[repeat(auto-fit,minmax(150px,1fr))] gap-2.5">
						<InfoItem label={t("node")} value={process.version} />
						<InfoItem
							label={t("platform")}
							value={`${process.platform} ${process.arch}`}
						/>
						<InfoItem label={t("appUptime")} value={uptime(process.uptime())} />
						<InfoItem
							label={t("heapUsed")}
							value={mb(process.memoryUsage().heapUsed)}
						/>
						<InfoItem label={t("rss")} value={mb(process.memoryUsage().rss)} />
						<InfoItem label={t("hostUptime")} value={uptime(os.uptime())} />
						<InfoItem
							label={t("load1m")}
							value={os.loadavg()[0]?.toFixed(2) ?? "—"}
						/>
						<InfoItem label={t("cpus")} value={os.cpus().length} />
					</div>
				</section>

				<section className="admin-card p-5">
					<h2 className="admin-section-title">{t("systemDiagnostics")}</h2>
					<div className="flex flex-col">
						<DiagnosticRow
							label={t("database")}
							detail={dbOk ? t("connectionHealthy") : t("unreachable")}
							state={dbOk ? "ok" : "danger"}
						/>
						<DiagnosticRow
							label={t("emulatorRcon")}
							detail={emulatorOnline ? t("respondingToPing") : t("noResponse")}
							state={emulatorOnline ? "ok" : "warn"}
						/>
						<DiagnosticRow
							label={t("rconConfig")}
							detail={rconSet ? t("rconHostSet") : t("rconHostNotConfigured")}
							state={rconSet ? "ok" : "warn"}
						/>
						<DiagnosticRow
							label={t("twoFaEncryptionKey")}
							detail={appKeySet ? t("appKeyConfigured") : t("appKeyMissing")}
							state={appKeySet ? "ok" : "warn"}
						/>
						<DiagnosticRow
							label={t("emailSmtp")}
							detail={smtpSet ? t("smtpHostSet") : t("notConfigured")}
							state={smtpSet ? "ok" : "warn"}
						/>
						<DiagnosticRow
							label={t("maintenanceMode")}
							detail={maintenance ? t("siteIsInMaintenance") : t("siteIsLive")}
							state={maintenance ? "warn" : "ok"}
						/>
					</div>
				</section>
			</div>

			<CommandocentrumControls />

			{/* ── Staff activity ─────────────────────────────────────── */}
			<section className="mt-6">
				<h2 className="admin-section-title">{t("recentStaffActivity")}</h2>
				{activity.length === 0 ? (
					<div className="admin-empty">{t("noStaffActivity")}</div>
				) : (
					<div className="admin-card overflow-x-auto">
						<table>
							<thead>
								<tr>
									<th>{t("colWhen")}</th>
									<th>{t("colStaff")}</th>
									<th>{t("colAction")}</th>
									<th>{t("colDescription")}</th>
								</tr>
							</thead>
							<tbody>
								{activity.map((a) => (
									<tr key={String(a.id)}>
										<td className="text-sm theme-text-muted dark:theme-text-muted whitespace-nowrap">
											{formatDate(a.createdAt, "datetime-seconds")}
										</td>
										<td>{nameById.get(Number(a.userId)) ?? `#${a.userId}`}</td>
										<td>
											<span className="inline-block text-[0.6rem] font-bold px-2 py-0.5 rounded-full bg-[var(--admin-accent)]/18 text-[var(--admin-text)]">
												{a.action}
											</span>
										</td>
										<td className="text-sm theme-text-muted dark:theme-text-muted">
											{a.description}
										</td>
									</tr>
								))}
							</tbody>
						</table>
					</div>
				)}
			</section>

			{/* ── Emulator errors ────────────────────────────────────── */}
			<section className="mt-6">
				<h2 className="admin-section-title">{t("recentEmulatorErrors")}</h2>
				{errors.length === 0 ? (
					<div className="admin-empty">{t("noEmulatorErrors")}</div>
				) : (
					<div className="admin-card overflow-x-auto">
						<table>
							<thead>
								<tr>
									<th>{t("colWhen")}</th>
									<th>{t("colType")}</th>
									<th>{t("colVersion")}</th>
									<th>{t("colStacktrace")}</th>
								</tr>
							</thead>
							<tbody>
								{errors.map((e) => {
									const trace = decodeStacktrace(e.stacktrace);
									const snippet = trace
										? trace.split("\n").slice(0, 20).join("\n") +
											(trace.split("\n").length > 20
												? `\n… ${t("truncated")}`
												: "")
										: t("empty");
									return (
										<tr key={e.id}>
											<td className="text-sm theme-text-muted dark:theme-text-muted whitespace-nowrap">
												{formatDate(
													e.timestamp ? new Date(e.timestamp * 1000) : null,
													"datetime-seconds",
												)}
											</td>
											<td>{e.type}</td>
											<td className="text-sm theme-text-muted dark:theme-text-muted whitespace-nowrap">
												{e.version}
											</td>
											<td>
												<pre className="text-xs p-2 bg-[var(--admin-canvas)] text-[var(--color-text-readable)] rounded overflow-auto max-h-[160px]">
													{snippet}
												</pre>
											</td>
										</tr>
									);
								})}
							</tbody>
						</table>
					</div>
				)}
			</section>
		</main>
	);
}