import { Badge } from "@/components/ui/badge";
import { Button } from "@/components/ui/button";
import {
	Table,
	TableBody,
	TableCell,
	TableHead,
	TableHeader,
	TableRow,
} from "@/components/ui/table";
import type { NowPlayingSession } from "../types";

interface Props {
	sessions: NowPlayingSession[];
	emptyMessage?: string;
	selectedUserLabel?: string;
	onSelectSession?: (session: NowPlayingSession) => void;
}

type SessionStateVariant = "success" | "warning" | "secondary";

/**
 * Map a session state onto a Badge variant per design §2.3.
 *
 * `playing` (active/healthy) → `success` (chart-2), `paused` → `warning`
 * (chart-3), anything else (idle/unknown) → `secondary` (neutral accent).
 */
function sessionStateVariant(state: string): SessionStateVariant {
	const normalized = String(state || "")
		.trim()
		.toLowerCase();
	if (normalized === "playing") return "success";
	if (normalized === "paused") return "warning";
	return "secondary";
}

function formatStateLabel(state: string): string {
	const normalized = String(state || "")
		.trim()
		.toLowerCase();
	if (normalized === "playing") {
		return "Playing";
	}
	if (normalized === "paused") {
		return "Paused";
	}
	if (normalized === "idle") {
		return "Idle";
	}
	return normalized
		? normalized.charAt(0).toUpperCase() + normalized.slice(1)
		: "Unknown";
}

function buildStatusSummary(sessions: NowPlayingSession[]) {
	const playing = sessions.filter(
		(session) =>
			String(session.state || "")
				.trim()
				.toLowerCase() === "playing",
	).length;
	const paused = sessions.filter(
		(session) =>
			String(session.state || "")
				.trim()
				.toLowerCase() === "paused",
	).length;
	const idle = sessions.filter(
		(session) =>
			String(session.state || "")
				.trim()
				.toLowerCase() === "idle",
	).length;
	return `${sessions.length} session${sessions.length === 1 ? "" : "s"} · ${playing} playing · ${paused} paused · ${idle} idle`;
}

export function SessionActivityPanel({
	sessions,
	emptyMessage = "No live sessions matched to this user.",
	selectedUserLabel,
	onSelectSession,
}: Props) {
	const userFallback = selectedUserLabel || "Unknown user";

	if (!sessions.length) {
		return <p className="text-sm text-muted-foreground">{emptyMessage}</p>;
	}

	return (
		<div className="max-h-[280px] overflow-auto rounded-lg border border-border">
			<Table aria-label="Session activity details" className="min-w-[880px]">
				<TableHeader>
					<TableRow className="bg-card hover:bg-card">
						<TableHead className="min-w-[160px]">User</TableHead>
						<TableHead className="w-[82px]">State</TableHead>
						<TableHead className="min-w-[140px]">Title / Type</TableHead>
						<TableHead className="min-w-[140px]">Device</TableHead>
						<TableHead className="w-[118px]">Transcoding</TableHead>
						{onSelectSession ? (
							<TableHead className="w-[150px]">Action</TableHead>
						) : null}
					</TableRow>
				</TableHeader>
				<TableBody>
					<TableRow className="bg-card hover:bg-card">
						<TableCell
							colSpan={onSelectSession ? 6 : 5}
							className="bg-card py-3"
						>
							<span className="text-xs text-muted-foreground">
								{buildStatusSummary(sessions)}
							</span>
						</TableCell>
					</TableRow>
					{sessions.map((session) => {
						const sessionLabel = formatStateLabel(session.state);
						return (
							<TableRow
								key={session.session_id}
								className={onSelectSession ? "cursor-pointer" : undefined}
								onClick={
									onSelectSession ? () => onSelectSession(session) : undefined
								}
							>
								<TableCell className="min-w-[160px]">
									<div
										className="truncate text-sm"
										title={session.user || userFallback}
									>
										{session.user || userFallback}
									</div>
									<div
										className="truncate text-xs text-muted-foreground"
										title={session.session_id}
									>
										{session.session_id}
									</div>
								</TableCell>
								<TableCell className="whitespace-nowrap">
									<Badge variant={sessionStateVariant(session.state)}>
										{sessionLabel}
									</Badge>
								</TableCell>
								<TableCell className="min-w-[140px]">
									<div className="truncate text-sm" title={session.title || ""}>
										{session.title || "(idle)"}
									</div>
									<div className="truncate text-xs text-muted-foreground">
										{session.type || "—"}
									</div>
								</TableCell>
								<TableCell className="min-w-[140px]">
									<div className="truncate text-sm">
										{session.device || "Unknown device"}
									</div>
								</TableCell>
								<TableCell className="whitespace-nowrap">
									<span className="text-sm">
										{session.transcoding === "yes"
											? session.transcoding_type
												? `yes (${session.transcoding_type})`
												: "yes"
											: "no"}
									</span>
								</TableCell>
								{onSelectSession ? (
									<TableCell className="whitespace-nowrap">
										<Button
											variant="outline"
											size="sm"
											onClick={(event) => {
												event.stopPropagation();
												onSelectSession(session);
											}}
										>
											Open in Users
										</Button>
									</TableCell>
								) : null}
							</TableRow>
						);
					})}
				</TableBody>
			</Table>
		</div>
	);
}