import type { WithLspClientOptions } from "../lsp/client-wrapper.js";
import type { SeverityFilter } from "../lsp/types.js";

export function isRecord(value: unknown): value is Record<string, unknown> {
	return typeof value === "object" && value !== null && !Array.isArray(value);
}

export function requireString(params: Record<string, unknown>, key: string): string {
	const value = params[key];
	if (typeof value !== "string" || value.length === 0) {
		throw new Error(`Missing required string parameter '${key}'`);
	}
	return value;
}

export function optionalString(params: Record<string, unknown>, key: string): string | undefined {
	const value = params[key];
	return typeof value === "string" ? value : undefined;
}

export function requireNumber(params: Record<string, unknown>, key: string): number {
	const value = params[key];
	if (typeof value !== "number" || !Number.isFinite(value)) {
		throw new Error(`Missing required number parameter '${key}'`);
	}
	return value;
}

export function optionalNumber(params: Record<string, unknown>, key: string): number | undefined {
	const value = params[key];
	return typeof value === "number" && Number.isFinite(value) ? value : undefined;
}

export function optionalBoolean(params: Record<string, unknown>, key: string): boolean | undefined {
	const value = params[key];
	return typeof value === "boolean" ? value : undefined;
}

export function severityFilter(params: Record<string, unknown>): SeverityFilter {
	const value = params["severity"];
	if (value === "error" || value === "warning" || value === "information" || value === "hint" || value === "all") {
		return value;
	}
	return "all";
}

export function clientOptions(signal: AbortSignal | undefined): WithLspClientOptions {
	return signal === undefined ? {} : { signal };
}