import type { FileError, Result } from "../../types.ts";
import { SessionError } from "../types.ts";

export class JsonlDecodeError extends Error {
	readonly kind: "syntax" | "schema";

	constructor(kind: "syntax" | "schema", message: string, cause?: Error) {
		super(message, cause === undefined ? undefined : { cause });
		this.name = "JsonlDecodeError";
		this.kind = kind;
	}
}

export function fileResult<T>(result: Result<T, FileError>, message: string): T {
	if (!result.ok) {
		throw new SessionError(
			result.error.code === "not_found" ? "not_found" : "storage",
			`${message}: ${result.error.message}`,
			result.error,
		);
	}
	return result.value;
}

export function invalidFile(path: string, line: number, cause: Error): SessionError {
	return new SessionError("invalid_entry", `Invalid JSONL v4 session ${path}: line ${line} ${cause.message}`, cause);
}