import { contourToSvgPath } from './contour';

/**
 * 卡片切割路径
 */
export interface CardPath {
  pageIndex: number;
  cardIndex: number;
  points: [number, number][];
  centerX: number;
  centerY: number;
  pathD: string;
  startPoint: [number, number];
  endPoint: [number, number];
}

/**
 * 生成空走路径（抬刀移动路径）
 * @param cardPaths 卡片切割路径
 * @param a4Height A4 纸高度（用于坐标转换）
 */
export function generateTravelPaths(
  cardPaths: CardPath[],
  a4Height: number
): [number, number][][] {
  const travelPaths: [number, number][][] = [];

  // 起点：左上角 (0, a4Height) - 注意 SVG 坐标 Y 向下，plotter 坐标 Y 向上
  const startPoint: [number, number] = [0, a4Height];

  if (cardPaths.length === 0) {
    return travelPaths;
  }

  // 从起点到第一张卡的起点
  travelPaths.push([startPoint, cardPaths[0].startPoint]);

  // 卡片之间的移动
  for (let i = 0; i < cardPaths.length - 1; i++) {
    const currentEnd = cardPaths[i].endPoint;
    const nextStart = cardPaths[i + 1].startPoint;
    travelPaths.push([currentEnd, nextStart]);
  }

  // 从最后一张卡返回起点
  travelPaths.push([cardPaths[cardPaths.length - 1].endPoint, startPoint]);

  return travelPaths;
}

/**
 * 将旅行路径转换为 SVG path 命令
 */
export function travelPathsToSvg(travelPaths: [number, number][][]): string {
  return travelPaths.map(path => contourToSvgPath(path, false)).join(' ');
}

/**
 * 计算所有卡片轮廓的总边界框
 */
export function calculateTotalBounds(cardPaths: CardPath[]): {
  minX: number;
  minY: number;
  maxX: number;
  maxY: number;
  width: number;
  height: number;
} {
  if (cardPaths.length === 0) {
    return { minX: 0, minY: 0, maxX: 0, maxY: 0, width: 0, height: 0 };
  }

  let minX = Infinity;
  let minY = Infinity;
  let maxX = -Infinity;
  let maxY = -Infinity;

  for (const cardPath of cardPaths) {
    for (const [x, y] of cardPath.points) {
      minX = Math.min(minX, x);
      minY = Math.min(minY, y);
      maxX = Math.max(maxX, x);
      maxY = Math.max(maxY, y);
    }
  }

  return {
    minX,
    minY,
    maxX,
    maxY,
    width: maxX - minX,
    height: maxY - minY
  };
}