import type {
	IExecuteFunctions,
	IDataObject,
	IHttpRequestOptions,
} from 'n8n-workflow';
import { NodeApiError, NodeOperationError } from 'n8n-workflow';

export interface ObsidianCommandResult extends IDataObject {
	id: string;
	command: string[];
	cwd: string;
	exit_code: number;
	stdout: string;
	stderr: string;
	duration_ms: number;
	timed_out: boolean;
	parsed_stdout?: IDataObject;
}

export interface ObsidianCredentials extends IDataObject {
	baseUrl: string;
	apiToken: string;
	defaultVault?: string;
}

export function compactArgs(args: Array<string | undefined | null | false>): string[] {
	return args.filter((arg): arg is string => typeof arg === 'string' && arg.length > 0);
}

export function kv(name: string, value: string | number | boolean | undefined | null): string | undefined {
	if (value === undefined || value === null || value === '') return undefined;
	if (typeof value === 'boolean') return value ? name : undefined;
	return `${name}=${value}`;
}

export function withVault(args: string[], vault?: string): string[] {
	if (!vault || args[0]?.startsWith('vault=')) return args;
	return [`vault=${vault}`, ...args];
}

export async function executeObsidianCommand(
	context: IExecuteFunctions,
	itemIndex: number,
	args: string[],
	options: { vault?: string; timeout?: number; stdin?: string } = {},
): Promise<ObsidianCommandResult> {
	const credentials = await context.getCredentials('obsidianApi') as ObsidianCredentials;
	const baseUrl = String(credentials.baseUrl).replace(/\/$/, '');
	const vault = options.vault || String(credentials.defaultVault || '');
	const finalArgs = withVault(args, vault);

	const request: IHttpRequestOptions = {
		method: 'POST',
		url: `${baseUrl}/commands`,
		headers: {
			Authorization: `Bearer ${credentials.apiToken}`,
			'Content-Type': 'application/json',
		},
		body: {
			args: finalArgs,
			stdin: options.stdin || undefined,
			timeout: options.timeout,
		},
		json: true,
		returnFullResponse: false,
	};

	let response: unknown;
	try {
		response = await context.helpers.httpRequest(request) as unknown;
	} catch (error) {
		throw toCleanApiError(context, error, itemIndex);
	}
	const result = normalizeCommandResult(response);

	const parsed = maybeParseStdout(result);
	if (parsed) result.parsed_stdout = parsed;

	if (result.exit_code !== 0) {
		throw new NodeOperationError(
			context.getNode(),
			`Obsidian CLI command failed with exit code ${result.exit_code}: ${result.stderr || result.stdout}`,
			{ itemIndex },
		);
	}

	return result;
}

function toCleanApiError(
	context: IExecuteFunctions,
	error: unknown,
	itemIndex: number,
): Error {
	const err = isObject(error) ? error : {};
	const statusCode = Number(
		err.statusCode ?? err.status ?? (isObject(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})`;

	// Build a plain-object error so n8n never tries to serialize the raw HTTP
	// response (it contains circular fields like res.socket._httpMessage).
	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 (isObject(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 (isObject(data)) {
		const candidate = data.detail ?? data.message ?? data.error;
		if (typeof candidate === 'string' && candidate) return candidate;
		if (isObject(candidate) && typeof candidate.message === 'string') return candidate.message;
	}
	return '';
}

function maybeParseStdout(result: ObsidianCommandResult): IDataObject | undefined {
	const cmd = result.command;
	const hasVault = cmd.includes('vault');
	const hasVaults = cmd.includes('vaults');

	if (!hasVault && !hasVaults) return undefined;

	const lines = (result.stdout || '')
		.split(/\r?\n/)
		.map((l) => l.trim())
		.filter(Boolean);

	if (!lines.length) return undefined;

	// vaults output is typically a 2-col tabular format: <name>\t<containerPath>
	if (hasVaults) {
		const vaults: Array<{ name: string; path: string }> = [];
		for (const line of lines) {
			const parts = line.split('\t');
			if (parts.length < 2) continue;
			const name = parts[0].trim();
			const path = parts.slice(1).join('\t').trim();
			if (!name || !path) continue;
			vaults.push({ name, path });
		}

		// Fallback: if parsing failed, return raw lines
		if (!vaults.length) return { vaults: lines };
		return { vaults };
	}

	// vault output is often key\tvalue pairs
	const kv: Record<string, string | number> = {};
	for (const line of lines) {
		const parts = line.split('\t');
		if (parts.length < 2) continue;
		const key = parts[0].trim();
		const rawValue = parts.slice(1).join('\t').trim();
		if (!key || !rawValue) continue;

		if (/^-?\d+$/.test(rawValue)) kv[key] = Number(rawValue);
		else kv[key] = rawValue;
	}

	return Object.keys(kv).length ? kv : undefined;
}

function normalizeCommandResult(response: unknown): ObsidianCommandResult {
	const data = extractResponseBody(response);
	const result = typeof data === 'string' ? JSON.parse(data) : data;

	if (!isObject(result)) {
		throw new Error('Obsidian API returned a non-object response');
	}

	return {
		id: String(result.id ?? ''),
		command: Array.isArray(result.command) ? result.command.map(String) : [],
		cwd: String(result.cwd ?? ''),
		exit_code: Number(result.exit_code ?? 0),
		stdout: String(result.stdout ?? ''),
		stderr: String(result.stderr ?? ''),
		duration_ms: Number(result.duration_ms ?? 0),
		timed_out: Boolean(result.timed_out),
	};
}

function extractResponseBody(response: unknown): unknown {
	if (!isObject(response)) return response;

	// Some n8n versions/helpers can return a full response object. Never pass that
	// through to node output because it contains circular fields like res.socket.
	if ('body' in response) return response.body;
	if ('data' in response) return response.data;

	return response;
}

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