/** 선형 치수 계열 — 선형·정렬·기준선·연속·빠른 치수·자동 치수 (조사표 5절) */
import { Circle, Point } from '@flatten-js/core';
import { toast } from 'react-toastify';
import { EntityName } from '../../entities/Entity';
import { MeasurementEntity } from '../../entities/MeasurementEntity';
import { sampleEntityPoints } from '../../helpers/geometry/sample-entity';
import { addEntities, getActiveLayerId, setSelectedEntityIds } from '../../state';
import { Tool } from '../../tools';
import { styled } from '../factories/entity-factory';
import { createSequenceTool } from '../factories/sequence-tool';
import { getLastDimension, rememberDimension } from './annotation.helpers';

/** 치수 객체 하나 만들기 — 현재 선 특성을 입히고 직전 치수로 기억한다 */
function makeDimension(start: Point, end: Point, offset: Point): MeasurementEntity {
	const dimension = styled(new MeasurementEntity(getActiveLayerId(), start, end, offset));
	rememberDimension(dimension);
	return dimension;
}

/**
 * 선형 치수 — 치수선을 놓은 방향으로 수평/수직을 고른다.
 * 위·아래에 놓으면 가로 거리, 좌·우에 놓으면 세로 거리를 잰다 (AutoCAD와 같다).
 */
function projectForLinear(start: Point, end: Point, offset: Point): [Point, Point] {
	const horizontalSpan = Math.abs(end.x - start.x);
	const verticalSpan = Math.abs(end.y - start.y);
	const offsetIsVertical =
		Math.abs(offset.y - (start.y + end.y) / 2) >= Math.abs(offset.x - (start.x + end.x) / 2);
	if (offsetIsVertical || horizontalSpan >= verticalSpan) {
		return [start, new Point(end.x, start.y)];
	}
	return [start, new Point(start.x, end.y)];
}

export const dimLinearToolStateMachine = createSequenceTool({
	tool: Tool.DIMLINEAR,
	steps: [
		{ kind: 'point', instructions: '첫 번째 치수보조선 원점을 지정하십시오.' },
		{ kind: 'point', instructions: '두 번째 치수보조선 원점을 지정하십시오.' },
		{ kind: 'point', instructions: '치수선 위치를 지정하십시오.' },
	],
	preview: (input) => {
		const points = input.points();
		if (points.length !== 2) return [];
		const [start, end] = projectForLinear(points[0], points[1], input.cursor);
		return [new MeasurementEntity(getActiveLayerId(), start, end, input.cursor)];
	},
	commit: (input) => {
		const [first, second, offset] = input.points();
		const [start, end] = projectForLinear(first, second, offset);
		addEntities([makeDimension(start, end, offset)], true);
	},
});

export const dimAlignedToolStateMachine = createSequenceTool({
	tool: Tool.DIMALIGNED,
	steps: [
		{ kind: 'point', instructions: '첫 번째 치수보조선 원점을 지정하십시오.' },
		{ kind: 'point', instructions: '두 번째 치수보조선 원점을 지정하십시오.' },
		{ kind: 'point', instructions: '치수선 위치를 지정하십시오.' },
	],
	preview: (input) => {
		const points = input.points();
		if (points.length !== 2) return [];
		return [new MeasurementEntity(getActiveLayerId(), points[0], points[1], input.cursor)];
	},
	commit: (input) => {
		const [start, end, offset] = input.points();
		addEntities([makeDimension(start, end, offset)], true);
	},
});

export const dimBaselineToolStateMachine = createSequenceTool({
	tool: Tool.DIMBASELINE,
	steps: [{ kind: 'point', instructions: '다음 치수보조선 원점을 지정하십시오.' }],
	commit: (input) => {
		const previous = getLastDimension();
		if (!previous) {
			toast.warn('먼저 치수를 하나 작성하십시오.');
			return;
		}
		const start = previous.getStartPoint();
		const offset = previous.getOffsetPoint();
		// 기준선 치수는 같은 시작점에서 재고, 치수선을 한 칸 더 띄운다
		const spacing = offset.distanceTo(start)[0] * 0.35 || 10;
		const direction = new Point(offset.x - start.x, offset.y - start.y);
		const length = Math.hypot(direction.x, direction.y) || 1;
		const nextOffset = new Point(
			offset.x + (direction.x / length) * spacing,
			offset.y + (direction.y / length) * spacing
		);
		addEntities([makeDimension(start, input.point(0), nextOffset)], true);
	},
});

export const dimContinueToolStateMachine = createSequenceTool({
	tool: Tool.DIMCONTINUE,
	steps: [{ kind: 'point', instructions: '다음 치수보조선 원점을 지정하십시오.' }],
	commit: (input) => {
		const previous = getLastDimension();
		if (!previous) {
			toast.warn('먼저 치수를 하나 작성하십시오.');
			return;
		}
		addEntities(
			[makeDimension(previous.getEndPoint(), input.point(0), previous.getOffsetPoint())],
			true
		);
	},
});

export const qDimToolStateMachine = createSequenceTool({
	tool: Tool.QDIM,
	helpers: false,
	steps: [
		{ kind: 'selection', instructions: '치수를 넣을 객체를 선택한 뒤 ENTER.' },
		{ kind: 'point', instructions: '치수선 위치를 지정하십시오.' },
	],
	commit: (input) => {
		const offset = input.point(1);
		const dimensions = input
			.entities(0)
			.map((entity) => {
				const points = sampleEntityPoints(entity);
				if (points.length < 2) return null;
				return makeDimension(points[0], points[points.length - 1], offset);
			})
			.filter((dimension): dimension is MeasurementEntity => !!dimension);
		if (!dimensions.length) {
			toast.warn('치수를 넣을 수 있는 객체가 없습니다.');
			return;
		}
		addEntities(dimensions, true);
		setSelectedEntityIds([]);
	},
});

/** DIM — 선택한 객체 종류에 맞는 치수를 자동으로 고른다 */
export const dimAutoToolStateMachine = createSequenceTool({
	tool: Tool.DIM,
	helpers: false,
	steps: [
		{ kind: 'entity', instructions: '치수를 넣을 객체를 선택하십시오.' },
		{ kind: 'point', instructions: '치수선 위치를 지정하십시오.' },
	],
	commit: (input) => {
		const entity = input.entity(0);
		const offset = input.point(1);
		const shape = entity.getShape();

		if (shape instanceof Circle || entity.getType() === EntityName.Arc) {
			// 원·호는 반지름 치수 명령이 더 알맞다
			toast.info('원·호에는 DIMRADIUS 또는 DIMDIAMETER를 사용하십시오.');
			return;
		}
		const points = sampleEntityPoints(entity);
		if (points.length < 2) {
			toast.warn('치수를 넣을 수 없는 객체입니다.');
			return;
		}
		addEntities([makeDimension(points[0], points[points.length - 1], offset)], true);
	},
});