const { CreateDocument } = require('../lib/document.js');

describe('Document', () => {
	let doc;
	const changes = [];

	beforeEach(() => {
		doc = new CreateDocument(change => changes.push(change));
		changes.splice(0, changes.length);
	});

	describe('element insertion', () => {
		it('to do nothing on creation', () => {
			const el = doc.createElement('div');
			expect(changes).toEqual([]);
		});

		it('to produce a patch upon append', () => {
			const el = doc.createElement('div');
			expect(changes).toEqual([]);
			doc.body.appendChild(el);
			expect(changes).toEqual([
				[
					0,
					doc.body._id,
					{
						t: 1,
						n: 'DIV',
						p: [],
						i: doc.body._id + 1,
						c: []
					},
					undefined
				]
			]);
		});

		it('to produce a patch upon append with a full tree', () => {
			const el1 = doc.createElement('div');
			const el2 = doc.createElement('span');
			expect(changes).toEqual([]);
			el1.appendChild(el2);
			expect(changes).toEqual([]);
			doc.body.appendChild(el1);
			expect(changes).toEqual([
				[
					0,
					doc.body._id,
					{
						t: 1,
						n: 'DIV',
						p: [],
						i: doc.body._id + 1,
						c: [
							{
								t: 1,
								n: 'SPAN',
								p: [],
								i: doc.body._id + 2,
								c: []
							}
						]
					},
					undefined
				]
			]);
			expect(changes.length).toEqual(1);
		});

		it('to produce a patch upon insert', () => {
			const el1 = doc.createElement('div');
			const el2 = doc.createElement('span');
			expect(changes).toEqual([]);
			doc.body.appendChild(el1);
			expect(changes).toEqual([
				[
					0,
					doc.body._id,
					{
						t: 1,
						n: 'DIV',
						p: [],
						i: doc.body._id + 1,
						c: []
					},
					undefined
				]
			]);
			doc.body.insertBefore(el2, el1);
			expect(changes.length).toEqual(2);
			expect(changes[1]).toEqual([
				0,
				doc.body._id,
				{
					t: 1,
					n: 'SPAN',
					p: [],
					i: doc.body._id + 2,
					c: []
				},
				doc.body._id + 1
			]);
		});
	});

	describe('element removal', () => {
		it('to propagate no changes after removal', () => {
			const el1 = doc.createElement('div');
			const el2 = doc.createElement('span');
			expect(changes).toEqual([]);
			el1.appendChild(el2);
			expect(changes).toEqual([]);
			doc.body.appendChild(el1);
			expect(changes).toEqual([
				[
					0,
					doc.body._id,
					{
						t: 1,
						n: 'DIV',
						p: [],
						i: doc.body._id + 1,
						c: [
							{
								t: 1,
								n: 'SPAN',
								p: [],
								i: doc.body._id + 2,
								c: []
							}
						]
					},
					undefined
				]
			]);
			expect(changes.length).toEqual(1);
			doc.body.removeChild(el1);
			expect(changes.length).toEqual(2);
			expect(changes[1]).toEqual([2, doc.body._id + 1]);
			el1.removeChild(el2);
			expect(changes.length).toEqual(2);
		});
	});

	describe('element attribute changes', () => {
		it('to propagate when attached', () => {
			const el1 = doc.createElement('div');
			const el2 = doc.createElement('span');
			el1.setAttribute('class', '1');
			expect(changes).toEqual([]);
			el1.appendChild(el2);
			expect(changes).toEqual([]);
			doc.body.appendChild(el1);
			expect(changes).toEqual([
				[
					0,
					doc.body._id,
					{
						t: 1,
						n: 'DIV',
						p: [{ ns: null, name: 'class', value: '1' }],
						i: doc.body._id + 1,
						c: [
							{
								t: 1,
								n: 'SPAN',
								p: [],
								i: doc.body._id + 2,
								c: []
							}
						]
					},
					undefined
				]
			]);
			expect(changes.length).toEqual(1);
			el2.setAttribute('class', '2');
			expect(changes.length).toEqual(2);
			expect(changes[1]).toEqual([1, doc.body._id + 2, { ns: null, name: 'class', value: '2' }]);
			el2.removeAttribute('class');
			expect(changes.length).toEqual(3);
			expect(changes[2]).toEqual([1, doc.body._id + 2, { name: 'class', value: null }]);
		});
	});
});