import type { IExecuteFunctions } from 'n8n-workflow';
import { NodeApiError } from 'n8n-workflow';

export function toCleanApiError(
	context: IExecuteFunctions,
	error: unknown,
	itemIndex: number,
): Error {
	const err = isRecord(error) ? error : {};
	const statusCode = Number(
		err.statusCode ?? err.status ?? (isRecord(err.response) ? err.response.statusCode : undefined) ?? 0,
	);
	const body = extractErrorBody(err);
	const detail = extractErrorMessage(body) || (typeof err.message === 'string' ? err.message : '');

	const statusText = statusCode ? `HTTP ${statusCode}` : 'Request failed';
	const message = detail
		? `Obsidian API error (${statusText}): ${detail}`
		: `Obsidian API error (${statusText})`;

	return new NodeApiError(
		context.getNode(),
		{ message, ...(statusCode ? { statusCode } : {}), ...(detail ? { detail } : {}) },
		{ message, description: detail || undefined, httpCode: statusCode ? String(statusCode) : undefined, itemIndex },
	);
}

function extractErrorBody(err: Record<string, unknown>): unknown {
	if ('body' in err && err.body !== undefined) return err.body;
	const response = err.response;
	if (isRecord(response)) {
		if ('body' in response && response.body !== undefined) return response.body;
		if ('data' in response && response.data !== undefined) return response.data;
	}
	if ('error' in err && err.error !== undefined) return err.error;
	return undefined;
}

function extractErrorMessage(body: unknown): string {
	let data: unknown = body;
	if (typeof data === 'string') {
		const trimmed = data.trim();
		if (!trimmed) return '';
		try {
			data = JSON.parse(trimmed);
		} catch {
			return trimmed;
		}
	}
	if (isRecord(data)) {
		const candidate = data.detail ?? data.message ?? data.error;
		if (typeof candidate === 'string' && candidate) return candidate;
		if (isRecord(candidate) && typeof candidate.message === 'string') return candidate.message;
	}
	return '';
}

function isRecord(value: unknown): value is Record<string, unknown> {
	return typeof value === 'object' && value !== null;
}