import { Builder, Parser } from 'xml2js';
import { IExecuteFunctions } from 'n8n-core';
import {
	INodeExecutionData,
	INodeType,
	INodeTypeDescription,
	IDataObject,
} from 'n8n-workflow';


export class Xml implements INodeType {
	description: INodeTypeDescription = {
		displayName: 'XML',
		name: 'xml',
		icon: 'fa:file-code',
		group: ['transform'],
		version: 1,
		subtitle: '={{$parameter["mode"]==="jsonToxml" ? "JSON to XML" : "XML to JSON"}}',
		description: 'Convert data from and to XML',
		defaults: {
			name: 'XML',
			color: '#333377',
		},
		inputs: ['main'],
		outputs: ['main'],
		properties: [
			{
				displayName: 'Mode',
				name: 'mode',
				type: 'options',
				options: [
					{
						name: 'JSON to XML',
						value: 'jsonToxml',
						description: 'Converts data from JSON to XML.',
					},
					{
						name: 'XML to JSON',
						value: 'xmlToJson',
						description: 'Converts data from XML to JSON',
					},
				],
				default: 'xmlToJson',
				description: 'From and to what format the data should be converted.',
			},

			// ----------------------------------
			//         option:jsonToxml
			// ----------------------------------
			{
				displayName: 'Property Name',
				name: 'dataPropertyName',
				type: 'string',
				displayOptions: {
					show: {
						mode: [
							'jsonToxml',
						],
					},
				},
				default: 'data',
				required: true,
				description: 'Name of the property to which to contains<br />the converted XML data.',
			},
			{
				displayName: 'Options',
				name: 'options',
				type: 'collection',
				placeholder: 'Add Option',
				displayOptions: {
					show: {
						mode: [
							'jsonToxml',
						],
					},
				},
				default: {},
				options: [
					{
						displayName: 'Allow Surrogate Chars',
						name: 'allowSurrogateChars',
						type: 'boolean',
						default: false,
						description: 'Allows using characters from the Unicode surrogate blocks.',
					},
					{
						displayName: 'Attribute Key',
						name: 'attrkey',
						type: 'string',
						default: '$',
						description: 'Prefix that is used to access the attributes.',
					},
					{
						displayName: 'cdata',
						name: 'cdata',
						type: 'boolean',
						default: false,
						description: ' wrap text nodes in <![CDATA[ ... ]]> instead of escaping when necessary. Does not add <![CDATA[ ... ]]> if it is not required.',
					},
					{
						displayName: 'Character Key',
						name: 'charkey',
						type: 'string',
						default: '_',
						description: 'Prefix that is used to access the character content.',
					},
					{
						displayName: 'Headless',
						name: 'headless',
						type: 'boolean',
						default: false,
						description: 'Omit the XML header.',
					},
					{
						displayName: 'Root Name',
						name: 'rootName',
						type: 'string',
						default: 'root',
						description: 'Root element name to be used.',
					},
				],
			},



			// ----------------------------------
			//         option:xmlToJson
			// ----------------------------------
			{
				displayName: 'Property Name',
				name: 'dataPropertyName',
				type: 'string',
				displayOptions: {
					show: {
						mode: [
							'xmlToJson',
						],
					},
				},
				default: 'data',
				required: true,
				description: 'Name of the property which contains<br />the XML data to convert.',
			},
			{
				displayName: 'Options',
				name: 'options',
				type: 'collection',
				placeholder: 'Add Option',
				displayOptions: {
					show: {
						mode: [
							'xmlToJson',
						],
					},
				},
				default: {},
				options: [
					{
						displayName: 'Attribute Key',
						name: 'attrkey',
						type: 'string',
						default: '$',
						description: 'Prefix that is used to access the attributes.',
					},
					{
						displayName: 'Character Key',
						name: 'charkey',
						type: 'string',
						default: '_',
						description: 'Prefix that is used to access the character content.',
					},
					{
						displayName: 'Explicit Array',
						name: 'explicitArray',
						type: 'boolean',
						default: false,
						description: 'Always put child nodes in an array if true; otherwise an array is created only if there is more than one.',
					},
					{
						displayName: 'Explicit Root',
						name: 'explicitRoot',
						type: 'boolean',
						default: true,
						description: 'Set this if you want to get the root node in the resulting object.',
					},
					{
						displayName: 'Ignore Attributes',
						name: 'ignoreAttrs',
						type: 'boolean',
						default: false,
						description: 'Ignore all XML attributes and only create text nodes.',
					},
					{
						displayName: 'Merge Attributes',
						name: 'mergeAttrs',
						type: 'boolean',
						default: true,
						description: 'Merge attributes and child elements as properties of the parent, instead of keying attributes off a child attribute object. This option is ignored if ignoreAttrs is true.',
					},
					{
						displayName: 'Normalize',
						name: 'normalize',
						type: 'boolean',
						default: false,
						description: 'Trim whitespaces inside text nodes.',
					},
					{
						displayName: 'Normalize Tags',
						name: 'normalizeTags',
						type: 'boolean',
						default: false,
						description: 'Normalize all tag names to lowercase.',
					},
					{
						displayName: 'Trim',
						name: 'trim',
						type: 'boolean',
						default: false,
						description: 'Trim the whitespace at the beginning and end of text nodes.',
					},
				],
			},
		]
	};


	async execute(this: IExecuteFunctions): Promise<INodeExecutionData[][]> {
		const items = this.getInputData();

		const mode = this.getNodeParameter('mode', 0) as string;
		const dataPropertyName = this.getNodeParameter('dataPropertyName', 0) as string;
		const options = this.getNodeParameter('options', 0, {}) as IDataObject;


		let item: INodeExecutionData;
		for (let itemIndex = 0; itemIndex < items.length; itemIndex++) {
			item = items[itemIndex];

			if (mode === 'xmlToJson') {
				const parserOptions = Object.assign({
					mergeAttrs: true,
					explicitArray: false,
				}, options);

				const parser = new Parser(parserOptions);

				if (item.json[dataPropertyName] === undefined) {
					throw new Error(`No json property "${dataPropertyName}" does not exists on item!`);
				}

				// @ts-ignore
				const json = await parser.parseStringPromise(item.json[dataPropertyName]);
				items[itemIndex] = { json };
			} else if (mode === 'jsonToxml') {
				const builder = new Builder(options);

				items[itemIndex] = {
					json: {
						[dataPropertyName]: builder.buildObject(items[itemIndex].json)
					}
				};
			} else {
				throw new Error(`The operation "${mode}" is not known!`);
			}
		}

		return this.prepareOutputData(items);

	}
}