/**
 * 반지름·지름·각도·호길이·세로좌표 치수와 중심 표식 (조사표 5절).
 * 오토캐드 물음 차례(337 설계 1-2) — DIMRADIUS · DIMDIAMETER = 「호 또는 원 선택:」 →
 * 「치수선의 위치 지정 또는 [문자(T)]:」 · 한 번 뒤 끝 · 그 밖 치수 = 물음 글만.
 */
import { Arc, Circle, Point } from '@flatten-js/core';
import { toast } from 'react-toastify';
import { OPT, type OptionSpec } from '../../commands/prompt';
import { logLine } from '../../commands/run-command';
import { getDimDecimals } from '../../commands/dim-settings';
import type { Entity } from '../../entities/Entity';
import { MeasurementEntity } from '../../entities/MeasurementEntity';
import { polylineLength, sampleEntityPoints } from '../../helpers/geometry/sample-entity';
import { addEntities, getEntities, setEntities, setSelectedEntityIds } from '../../state';
import { Tool } from '../../tools';
import { arcEntity, lineEntity } from '../factories/entity-factory';
import { createSequenceTool, type SequenceInput } from '../factories/sequence-tool';
import { annotationText, arrowHead, dimensionText } from './annotation.helpers';

interface CircularShape {
	center: Point;
	radius: number;
}

/** 원·호에서 중심과 반지름을 꺼낸다 */
function circularOf(entity: Entity): CircularShape | null {
	const shape = entity.getShape();
	if (shape instanceof Circle) return { center: shape.center, radius: Number(shape.r) };
	if (shape instanceof Arc) return { center: shape.center, radius: Number(shape.r) };
	return null;
}

/** 잰 값 글(「R10.00」 · 「Ø20.00」) */
function radialLabel(entity: Entity, diameter: boolean): string | null {
	const circular = circularOf(entity);
	if (!circular) return null;
	const value = diameter ? circular.radius * 2 : circular.radius;
	return `${diameter ? 'Ø' : 'R'}${value.toFixed(getDimDecimals())}`;
}

/** 바꾼 글(`<>` = 잰 값) · 없으면 잰 값 */
const labelWith = (measured: string, text?: string) =>
	text && text !== '<>' ? text.replaceAll('<>', measured) : measured;

function radialDimension(
	entity: Entity,
	textPoint: Point,
	diameter: boolean,
	text?: string
): Entity[] | null {
	const circular = circularOf(entity);
	if (!circular) return null;

	const angle = Math.atan2(textPoint.y - circular.center.y, textPoint.x - circular.center.x);
	const edge = new Point(
		circular.center.x + circular.radius * Math.cos(angle),
		circular.center.y + circular.radius * Math.sin(angle)
	);
	const start = diameter
		? new Point(
				circular.center.x - circular.radius * Math.cos(angle),
				circular.center.y - circular.radius * Math.sin(angle)
			)
		: circular.center;

	return [
		lineEntity(start, textPoint),
		arrowHead(edge, circular.center),
		text && text !== '<>'
			? annotationText(labelWith(radialLabel(entity, diameter) as string, text), textPoint)
			: dimensionText(
					diameter ? circular.radius * 2 : circular.radius,
					textPoint,
					diameter ? 'Ø' : 'R'
				),
	];
}

const MTEXT: OptionSpec = { key: 'MTEXT', kw: 'M', en: 'MTEXT', label: '여러 줄 문자' };
const ANGLE: OptionSpec = { key: 'ANGLE', kw: 'A', en: 'ANGLE', label: '각도' };

/** DIMRADIUS · DIMDIAMETER — 원 · 호 → [문자(T)] → 위치 */
function radialTool(tool: Tool, diameter: boolean) {
	const measured = (input: SequenceInput) =>
		input.has('obj') ? radialLabel(input.get<Entity>('obj'), diameter) : null;
	return createSequenceTool({
		tool,
		steps: [
			{ kind: 'entity', id: 'obj', prompt: { text: '호 또는 원 선택' } },
			{
				kind: 'text',
				id: 'txt',
				when: (input) => input.mode === 'text',
				next: 'place',
				defaultValue: '<>',
				prompt: (input) => {
					const value = measured(input);
					return {
						text: '치수 문자 입력',
						...(value === null ? {} : { default: { kind: 'enter' as const, label: value } }),
					};
				},
			},
			{
				kind: 'point',
				id: 'place',
				prompt: { text: '치수선의 위치 지정', options: [OPT.TEXT], absent: [MTEXT, ANGLE] },
				options: { TEXT: { mode: 'text', next: 'txt' } },
			},
		],
		commit: (input) => {
			const entity = input.get<Entity>('obj');
			const text = input.has('txt') ? input.get<string>('txt') : undefined;
			const parts = radialDimension(entity, input.get<Point>('place'), diameter, text);
			if (!parts) {
				toast.warn('원 또는 호를 선택하십시오.');
				return;
			}
			addEntities(parts, true);
			logLine(`치수 문자 = ${labelWith(radialLabel(entity, diameter) as string, text)}`);
		},
	});
}

export const dimRadiusToolStateMachine = radialTool(Tool.DIMRADIUS, false);
export const dimDiameterToolStateMachine = radialTool(Tool.DIMDIAMETER, true);

export const dimAngularToolStateMachine = createSequenceTool({
	tool: Tool.DIMANGULAR,
	steps: [
		{ kind: 'point', prompt: { text: '각도 정점 지정' } },
		{ kind: 'point', prompt: { text: '첫 번째 각도 끝점 지정' } },
		{ kind: 'point', prompt: { text: '두 번째 각도 끝점 지정' } },
	],
	commit: (input) => {
		const [vertex, first, second] = input.points();
		const radius = Math.min(vertex.distanceTo(first)[0], vertex.distanceTo(second)[0]) * 0.6;
		if (radius <= 0) return;

		const startAngle = Math.atan2(first.y - vertex.y, first.x - vertex.x);
		const endAngle = Math.atan2(second.y - vertex.y, second.x - vertex.x);
		const sweep = (endAngle - startAngle + 2 * Math.PI) % (2 * Math.PI);
		const midAngle = startAngle + sweep / 2;
		const degrees = (sweep * 180) / Math.PI;

		addEntities(
			[
				lineEntity(vertex, first),
				lineEntity(vertex, second),
				arcEntity({
					center: vertex,
					radius,
					startAngle,
					endAngle,
					counterClockwise: true,
				}),
				annotationText(
					`${degrees.toFixed(getDimDecimals())}°`,
					new Point(
						vertex.x + radius * 1.25 * Math.cos(midAngle),
						vertex.y + radius * 1.25 * Math.sin(midAngle)
					)
				),
			],
			true
		);
	},
});

export const dimArcToolStateMachine = createSequenceTool({
	tool: Tool.DIMARC,
	steps: [
		{ kind: 'entity', prompt: { text: '호 또는 폴리선 호 세그먼트 선택' } },
		{ kind: 'point', prompt: { text: '호 길이 치수 위치 지정' } },
	],
	commit: (input) => {
		const entity = input.entity(0);
		const circular = circularOf(entity);
		if (!circular) {
			toast.warn('호를 선택하십시오.');
			return;
		}
		const length = polylineLength(sampleEntityPoints(entity));
		addEntities([dimensionText(length, input.point(1), '⌒ ')], true);
	},
});

export const dimOrdinateToolStateMachine = createSequenceTool({
	tool: Tool.DIMORDINATE,
	steps: [
		{ kind: 'point', prompt: { text: '피쳐 위치 지정' } },
		{ kind: 'point', prompt: { text: '지시선 끝점 지정' } },
	],
	commit: (input) => {
		const [feature, leaderEnd] = input.points();
		// 지시선이 세로로 길면 X좌표를, 가로로 길면 Y좌표를 기입한다 (AutoCAD와 같다)
		const vertical = Math.abs(leaderEnd.y - feature.y) >= Math.abs(leaderEnd.x - feature.x);
		const value = vertical ? feature.x : feature.y;
		addEntities(
			[
				lineEntity(feature, leaderEnd),
				annotationText(
					`${vertical ? 'X' : 'Y'} ${value.toFixed(getDimDecimals())}`,
					new Point(leaderEnd.x, leaderEnd.y)
				),
			],
			true
		);
	},
});

export const centerMarkToolStateMachine = createSequenceTool({
	tool: Tool.CENTERMARK,
	steps: [{ kind: 'entity', instructions: '중심 표식을 넣을 원 또는 호를 선택하십시오.' }],
	commit: (input) => {
		const circular = circularOf(input.entity(0));
		if (!circular) {
			toast.warn('원 또는 호를 선택하십시오.');
			return;
		}
		const size = circular.radius * 0.15;
		addEntities(
			[
				lineEntity(
					new Point(circular.center.x - size, circular.center.y),
					new Point(circular.center.x + size, circular.center.y)
				),
				lineEntity(
					new Point(circular.center.x, circular.center.y - size),
					new Point(circular.center.x, circular.center.y + size)
				),
			],
			true
		);
	},
});

export const centerLineToolStateMachine = createSequenceTool({
	tool: Tool.CENTERLINE,
	helpers: false,
	steps: [
		{ kind: 'entity', instructions: '첫 번째 선을 선택하십시오.' },
		{ kind: 'entity', instructions: '두 번째 선을 선택하십시오.' },
	],
	commit: (input) => {
		const first = sampleEntityPoints(input.entity(0));
		const second = sampleEntityPoints(input.entity(1));
		if (first.length < 2 || second.length < 2) {
			toast.warn('두 선을 선택하십시오.');
			return;
		}
		const middle = (a: Point, b: Point) => new Point((a.x + b.x) / 2, (a.y + b.y) / 2);
		const line = lineEntity(
			middle(first[0], second[0]),
			middle(first[first.length - 1], second[second.length - 1])
		);
		line.lineDash = [12, 4, 2, 4];
		addEntities([line], true);
	},
});

/** DIMSPACE — 선택한 치수들의 치수선 간격을 고르게 맞춘다 */
export const dimSpaceToolStateMachine = createSequenceTool({
	tool: Tool.DIMSPACE,
	helpers: false,
	steps: [
		{ kind: 'selection', instructions: '간격을 맞출 치수를 선택한 뒤 ENTER.' },
		{ kind: 'number', instructions: '치수선 간격을 입력하십시오 <10>.', defaultValue: 10 },
	],
	commit: (input) => {
		const dimensions = input
			.entities(0)
			.filter((entity): entity is MeasurementEntity => entity instanceof MeasurementEntity);
		if (dimensions.length < 2) {
			toast.warn('치수를 두 개 이상 선택하십시오.');
			return;
		}
		const spacing = input.number(1);
		const base = dimensions[0];
		const baseStart = base.getStartPoint();
		const baseOffset = base.getOffsetPoint();
		const direction = new Point(baseOffset.x - baseStart.x, baseOffset.y - baseStart.y);
		const length = Math.hypot(direction.x, direction.y) || 1;

		dimensions.forEach((dimension, index) => {
			if (index === 0) return;
			const start = dimension.getStartPoint();
			dimension.setOffsetPoint(
				new Point(
					start.x + (direction.x / length) * (length + spacing * index),
					start.y + (direction.y / length) * (length + spacing * index)
				)
			);
		});
		setEntities([...getEntities()], true);
		setSelectedEntityIds([]);
	},
});