function basename(modelId: string): string {
	return modelId.split("/").at(-1) ?? modelId;
}

function withoutTrailingQualifiers(
	value: string,
	qualifiers: ReadonlySet<string>,
): string {
	const parts = value.split("-");
	while (parts.length > 0 && qualifiers.has(parts.at(-1)?.toLowerCase() ?? ""))
		parts.pop();
	return parts.join("-");
}

const GEMINI_QUALIFIERS = new Set([
	"customtools",
	"image",
	"latest",
	"live",
	"preview",
]);
const HIGHSPEED_QUALIFIER = new Set(["highspeed"]);
const KIMI_QUALIFIERS = new Set(["highspeed", "preview", "turbo"]);
const RELEASE_QUALIFIERS = new Set(["latest"]);

/** Compact a model ID according to its family's stable naming grammar. */
export function shortModelLabel(modelId: string): string {
	const id = basename(modelId);
	let match: RegExpExecArray | null;

	match = /^gpt-(\d+(?:\.\d+)*)(?:-(.+))?$/iu.exec(id);
	if (match) return match[2] ?? id;

	match = /^claude-([^-]+)-\d/iu.exec(id);
	if (match) return match[1] ?? id;

	match = /^gemini-(\d+(?:\.\d+)?)-(.+)$/iu.exec(id);
	if (match) {
		const variant = withoutTrailingQualifiers(
			match[2] ?? "",
			GEMINI_QUALIFIERS,
		);
		return variant ? `${match[1]}-${variant}` : id;
	}
	match = /^gemini-(.+)$/iu.exec(id);
	if (match)
		return withoutTrailingQualifiers(match[1] ?? id, GEMINI_QUALIFIERS);

	if (/^grok-\d/iu.test(id)) return id;

	match = /^deepseek-(v?\d+(?:\.\d+)?)-(flash|pro)(?:-|$)/iu.exec(id);
	if (match) return `${match[1]}-${match[2]}`;

	match = /^minimax-(m\d+(?:\.\d+)?)(?:-(.+))?$/iu.exec(id);
	if (match) return match[1] ?? id;

	match = /^kimi-(k\d+(?:\.\d+)?)(?:-(.+))?$/iu.exec(id);
	if (match) {
		const variant = withoutTrailingQualifiers(match[2] ?? "", KIMI_QUALIFIERS);
		return variant ? `${match[1]}-${variant}` : (match[1] ?? id);
	}
	if (/^kimi-for-coding(?:-highspeed)?$/iu.test(id)) return "kimi-coding";

	match = /^glm-(\d+(?:\.\d+)?)(?:-(.+))?$/iu.exec(id);
	if (match) {
		const variant = withoutTrailingQualifiers(
			match[2] ?? "",
			HIGHSPEED_QUALIFIER,
		);
		return `glm-${match[1]}${variant ? `-${variant}` : ""}`;
	}

	if (
		/^(?:codestral|devstral|magistral|ministral|mistral|pixtral|voxtral)-/iu.test(
			id,
		)
	) {
		const withoutRelease = id.replace(/-(?:\d{4}|\d{8})$/u, "");
		return withoutTrailingQualifiers(withoutRelease, RELEASE_QUALIFIERS);
	}

	return id;
}