export interface JsonRpcRequest {
  jsonrpc: "2.0";
  id?: number | string | null;
  method: string;
  params?: unknown;
}

export interface JsonRpcResponse {
  jsonrpc: "2.0";
  id: number | string | null;
  result?: unknown;
  error?: JsonRpcError;
}

export interface JsonRpcError {
  code: number;
  message: string;
  data?: unknown;
}

export const PARSE_ERROR = -32700;
export const INVALID_REQUEST = -32600;
export const METHOD_NOT_FOUND = -32601;
export const INVALID_PARAMS = -32602;
export const INTERNAL_ERROR = -32603;

export interface ToolDefinition {
  name: string;
  description: string;
  inputSchema: Record<string, unknown>;
  handler: (args: Record<string, unknown>) => Promise<ToolResult>;
}

export interface ToolResult {
  content: { type: "text"; text: string }[];
  isError?: boolean;
}

export function ok(id: number | string | null, result: unknown): JsonRpcResponse {
  return { jsonrpc: "2.0", id, result };
}

export function fail(id: number | string | null, code: number, message: string, data?: unknown): JsonRpcResponse {
  return { jsonrpc: "2.0", id, error: { code, message, data } };
}