/* eslint-disable n8n-nodes-base/node-execute-block-wrong-error-thrown */
import { NodesConfig } from '@n8n/config';
import { Container } from '@n8n/di';
import {
	NodeConnectionTypes,
	UnexpectedError,
	UserError,
	type CodeExecutionMode,
	type CodeNodeEditorLanguage,
	type IExecuteFunctions,
	type INodeType,
	type INodeTypeDescription,
} from 'n8n-workflow';

type CodeNodeLanguageOption = CodeNodeEditorLanguage | 'pythonNative';

import { javascriptCodeDescription } from './descriptions/JavascriptCodeDescription';
import { pythonCodeDescription } from './descriptions/PythonCodeDescription';
import { JsTaskRunnerSandbox } from './JsTaskRunnerSandbox';
import { PythonRunnerUnavailableError } from './python-runner-unavailable.error';
import { PythonTaskRunnerSandbox } from './PythonTaskRunnerSandbox';

class PythonDisabledError extends UserError {
	constructor() {
		super(
			'This instance disallows Python execution because it has the environment variable `N8N_PYTHON_ENABLED` set to `false`. To restore Python execution, remove this environment variable or set it to `true` and restart the instance.',
		);
	}
}

export class Code implements INodeType {
	description: INodeTypeDescription = {
		displayName: 'Code',
		name: 'code',
		icon: 'node:code',
		iconColor: 'amber',
		group: ['transform'],
		version: [1, 2],
		defaultVersion: 2,
		description: 'Run custom JavaScript or Python code',
		defaults: {
			name: 'Code',
		},
		inputs: [NodeConnectionTypes.Main],
		outputs: [NodeConnectionTypes.Main],
		builderHint: {
			searchHint:
				'Use Code node as a LAST RESORT — it runs in a sandboxed environment and is slower than native nodes. Code node is ONLY appropriate for complex multi-step algorithms that cannot be expressed in single expressions, or operations requiring complex data structures.',
			relatedNodes: [
				{
					nodeType: 'n8n-nodes-base.set',
					relationHint:
						'Use this instead for data manipulation: add/modify/rename fields, set values, map data',
				},
				{
					nodeType: 'n8n-nodes-base.filter',
					relationHint: 'Use this instead for filtering items by condition',
				},
				{
					nodeType: 'n8n-nodes-base.if',
					relationHint: 'Use this instead for routing by condition',
				},
				{
					nodeType: 'n8n-nodes-base.switch',
					relationHint: 'Use this instead for multi-way routing by condition',
				},
				{
					nodeType: 'n8n-nodes-base.splitOut',
					relationHint: 'Use this instead for splitting arrays into separate items',
				},
				{
					nodeType: 'n8n-nodes-base.aggregate',
					relationHint: 'Use this instead for combining multiple items into one',
				},
				{
					nodeType: 'n8n-nodes-base.summarize',
					relationHint: 'Use this instead for summarizing or pivoting data',
				},
				{
					nodeType: 'n8n-nodes-base.removeDuplicates',
					relationHint: 'Use this instead for removing duplicates',
				},
				{
					nodeType: 'n8n-nodes-base.limit',
					relationHint: 'Use this instead to reduce the number of items returned',
				},
				{
					nodeType: 'n8n-nodes-base.merge',
					relationHint: 'Use this instead for merging data from multiple branches',
				},
				{
					nodeType: 'n8n-nodes-base.dateTime',
					relationHint: 'Use this instead for date time operations',
				},
				{
					nodeType: 'n8n-nodes-base.html',
					relationHint: 'Use this instead for creating html pages',
				},
			],
		},
		parameterPane: 'wide',
		properties: [
			{
				displayName: 'Mode',
				name: 'mode',
				type: 'options',
				noDataExpression: true,
				options: [
					{
						name: 'Run Once for All Items',
						value: 'runOnceForAllItems',
						description: 'Run this code only once, no matter how many input items there are',
					},
					{
						name: 'Run Once for Each Item',
						value: 'runOnceForEachItem',
						description: 'Run this code as many times as there are input items',
					},
				],
				default: 'runOnceForAllItems',
			},
			{
				displayName: 'Language',
				name: 'language',
				type: 'options',
				noDataExpression: true,
				displayOptions: {
					show: {
						'@version': [2],
					},
				},
				options: [
					{
						name: 'JavaScript',
						value: 'javaScript',
						action: 'Code in JavaScript',
					},
					{
						name: 'Python',
						value: 'pythonNative',
						action: 'Code in Python',
					},
				],
				default: 'javaScript',
			},
			{
				displayName: 'Language',
				name: 'language',
				type: 'hidden',
				displayOptions: {
					show: {
						'@version': [1],
					},
				},
				default: 'javaScript',
			},

			...javascriptCodeDescription,
			...pythonCodeDescription,
		],
	};

	async execute(this: IExecuteFunctions) {
		const node = this.getNode();
		const language: CodeNodeLanguageOption =
			node.typeVersion === 2
				? (this.getNodeParameter('language', 0) as CodeNodeLanguageOption)
				: 'javaScript';

		const isJsLang = language === 'javaScript';
		const isPyLang = language === 'python' || language === 'pythonNative'; // keep legacy `python` for backwards compatibility
		if (isPyLang && !Container.get(NodesConfig).pythonEnabled) {
			throw new PythonDisabledError();
		}

		const nodeMode = this.getNodeParameter('mode', 0) as CodeExecutionMode;
		const workflowMode = this.getMode();
		const codeParameterName = isPyLang ? 'pythonCode' : 'jsCode';

		if (isJsLang) {
			const code = this.getNodeParameter(codeParameterName, 0) as string;
			const sandbox = new JsTaskRunnerSandbox(workflowMode, this);
			const numInputItems = this.getInputData().length;

			return nodeMode === 'runOnceForAllItems'
				? [await sandbox.runCodeAllItems(code)]
				: [await sandbox.runCodeForEachItem(code, numInputItems)];
		}

		if (isPyLang) {
			const runnerStatus = this.getRunnerStatus('python');
			if (!runnerStatus.available) {
				throw new PythonRunnerUnavailableError(
					runnerStatus.reason as 'python' | 'venv' | undefined,
				);
			}

			const code = this.getNodeParameter(codeParameterName, 0) as string;
			const sandbox = new PythonTaskRunnerSandbox(code, nodeMode, workflowMode, this);

			return [await sandbox.runUsingIncomingItems()];
		}

		throw new UnexpectedError(`Unsupported language: ${language}`);
	}
}