/** 그리기 명령 — 스플라인·점·도넛 + 폴리선·호·다각형·타원 다시 내보냄 (조사표 1절 · 337 설계 1-1) */
import { CircleEntity } from '../../entities/CircleEntity';
import type { Entity } from '../../entities/Entity';
import type { Point } from '@flatten-js/core';
import { OPT } from '../../commands/prompt';
import { splinePoints } from '../../helpers/geometry/shape-points';
import { addEntities, getActiveLayerId } from '../../state';
import { Tool } from '../../tools';
import { pointEntity, polyLineEntity, styled } from '../factories/entity-factory';
import { createSequenceTool } from '../factories/sequence-tool';
import { option } from './draw-steps';

export { arcToolStateMachine } from './arc-tool';
export { ellipseToolStateMachine } from './ellipse-tool';
export { plineToolStateMachine } from './pline-tool';
export { polygonToolStateMachine } from './polygon-tool';

/** 닫힌 스플라인 — 끝 둘레 이웃을 이어 붙여 그린 뒤 이음 구간만 남김 */
function closedSplinePoints(points: Point[]): Point[] {
	const spans = 12;
	const wrapped = splinePoints([points[points.length - 1], ...points, points[0], points[1]], spans);
	const loop = wrapped.slice(spans, spans * (points.length + 1));
	return [...loop, loop[0]];
}

const NEXT_POINT = '다음 점 입력';
const TOLERANCE = option('TOLERANCE', 'L', '공차');

/**
 * 스플라인(SPLINE) — 337 설계 1-1. 「첫 번째 점 지정:」 → 「다음 점 입력:」 → 「다음 점 입력 또는 [명령 취소(U)]:」 →
 * 넷째 점부터 [명령 취소(U)/닫기(C)] 되풀이 · 빈 Enter = 확정 · C = 닫고 끝 · Esc = 버림.
 */
export const splineToolStateMachine = createSequenceTool({
	tool: Tool.SPLINE,
	steps: [
		{
			kind: 'point',
			prompt: {
				text: '첫 번째 점 지정',
				absent: [
					option('METHOD', 'M', '방법'),
					option('KNOTS', 'K', '매듭'),
					option('OBJECT', 'O', '객체'),
				],
			},
		},
		{
			kind: 'point',
			prompt: {
				text: NEXT_POINT,
				absent: [option('TANGENT', 'T', '시작 접촉부'), TOLERANCE],
			},
		},
		{
			kind: 'point',
			prompt: (input) => ({
				text: NEXT_POINT,
				options: input.points().length >= 3 ? [OPT.UNDO, OPT.CLOSE] : [OPT.UNDO],
				absent: [option('TANGENT', 'T', '끝 접촉부'), TOLERANCE],
			}),
			options: { UNDO: 'undo', CLOSE: 'close' },
		},
	],
	repeatLastStep: true,
	preview: (input) => {
		const preview = polyLineEntity(splinePoints([...input.points(), input.cursor]));
		return preview ? [preview] : [];
	},
	commit: (input) => {
		const points = input.points();
		const spline = polyLineEntity(input.closed ? closedSplinePoints(points) : splinePoints(points));
		if (spline) addEntities([spline], true);
	},
});

export const pointToolStateMachine = createSequenceTool({
	tool: Tool.POINT,
	steps: [{ kind: 'point', instructions: '점의 위치를 지정하십시오.' }],
	preview: (input) => [pointEntity(input.cursor)],
	commit: (input) => {
		addEntities([pointEntity(input.point(0))], true);
	},
});

/** 도넛 — 안쪽·바깥쪽 지름을 받아 동심원 두 개를 놓는다 */
export const donutToolStateMachine = createSequenceTool({
	tool: Tool.DONUT,
	steps: [
		{ kind: 'number', instructions: '도넛의 내부 지름을 입력하십시오 <1>.', defaultValue: 1 },
		{ kind: 'number', instructions: '도넛의 외부 지름을 입력하십시오 <2>.', defaultValue: 2 },
		{ kind: 'point', instructions: '도넛의 중심을 지정하십시오.' },
	],
	loopFrom: 2, // 오토캐드 — 중심 되풀이 · 빈 Enter 끝
	preview: (input) => donutEntities(input.number(0), input.number(1), input.cursor),
	commit: (input) => {
		addEntities(donutEntities(input.number(0), input.number(1), input.point(2)), true);
	},
});

function donutEntities(
	innerDiameter: number,
	outerDiameter: number,
	center: Parameters<typeof pointEntity>[0]
): Entity[] {
	const circles: Entity[] = [];
	for (const diameter of [innerDiameter, outerDiameter]) {
		if (diameter > 0) {
			circles.push(styled(new CircleEntity(getActiveLayerId(), center, diameter / 2)));
		}
	}
	return circles;
}