ttrpg-tools/src/components/md-deck/hooks/usePlotterExport.ts

import type { DeckStore } from './deckStore';
import type { PageData } from './usePDFExport';
import type { CardShape } from '../types';
import { pts2plotter } from '../../../plotcutter';

export interface CardPathData {
  points: [number, number][];
  centerX: number;
  centerY: number;
}

export interface PltExportData {
  paths: CardPathData[];
  plotterCode: string;
  a4Width: number;
  a4Height: number;
}

export interface UsePlotterExportReturn {
  generatePltData: (pages: PageData[]) => PltExportData | null;
  downloadPltFile: (plotterCode: string) => void;
  exportToPlt: (pages: PageData[]) => void;
}

/**
 * 根据形状生成卡片轮廓点（单位：mm，相对于卡片左下角）
 * @param shape 卡片形状
 * @param width 卡片宽度（切割尺寸，不含出血）
 * @param height 卡片高度（切割尺寸，不含出血）
 */
function getCardShapePoints(
  shape: CardShape,
  width: number,
  height: number
): [number, number][] {
  const points: [number, number][] = [];

  switch (shape) {
    case 'circle': {
      const radius = Math.min(width, height) / 2;
      const centerX = width / 2;
      const centerY = height / 2;
      for (let i = 0; i < 36; i++) {
        const angle = (i / 36) * Math.PI * 2;
        points.push([
          centerX + radius * Math.cos(angle),
          centerY + radius * Math.sin(angle)
        ]);
      }
      break;
    }
    case 'triangle': {
      points.push([width / 2, 0]);
      points.push([0, height]);
      points.push([width, height]);
      break;
    }
    case 'hexagon': {
      const halfW = width / 2;
      const quarterH = height / 4;
      points.push([halfW, 0]);
      points.push([width, quarterH]);
      points.push([width, height - quarterH]);
      points.push([halfW, height]);
      points.push([0, height - quarterH]);
      points.push([0, quarterH]);
      break;
    }
    case 'rectangle':
    default: {
      points.push([0, 0]);
      points.push([width, 0]);
      points.push([width, height]);
      points.push([0, height]);
      break;
    }
  }

  return points;
}

/**
 * 计算多边形的中心点
 */
function calculateCenter(points: [number, number][]): { x: number; y: number } {
  let sumX = 0;
  let sumY = 0;
  for (const [x, y] of points) {
    sumX += x;
    sumY += y;
  }
  return {
    x: sumX / points.length,
    y: sumY / points.length
  };
}

/**
 * PLT 导出 hook - 生成 HPGL 格式文件并下载
 */
export function usePlotterExport(store: DeckStore): UsePlotterExportReturn {
  const bleed = () => store.state.bleed || 1;
  const cardWidth = () => store.state.dimensions?.cardWidth || 56;
  const cardHeight = () => store.state.dimensions?.cardHeight || 88;
  const shape = () => store.state.shape;
  const a4Width = 297; // 横向 A4
  const a4Height = 210;

  /**
   * 生成 PLT 数据（不下载，用于预览）
   */
  const generatePltData = (pages: PageData[]): PltExportData | null => {
    const paths: CardPathData[] = [];
    const currentBleed = bleed();

    // 计算切割尺寸（排版尺寸减去出血）
    const cutWidth = cardWidth() - currentBleed * 2;
    const cutHeight = cardHeight() - currentBleed * 2;

    for (const page of pages) {
      for (const card of page.cards) {
        if (card.side !== 'front') continue;

        // 获取卡片形状点（相对于卡片原点，使用切割尺寸）
        const shapePoints = getCardShapePoints(shape(), cutWidth, cutHeight);

        // 转换点到页面坐标：
        // - X 轴：卡片位置 + 出血偏移
        // - Y 轴：翻转（SVG Y 向下，plotter Y 向上）
        const pagePoints = shapePoints.map(([x, y]) => [
          card.x + currentBleed + x,
          a4Height - (card.y + currentBleed + y)
        ] as [number, number]);

        const center = calculateCenter(pagePoints);
        paths.push({
          points: pagePoints,
          centerX: center.x,
          centerY: center.y
        });
      }
    }

    if (paths.length === 0) {
      return null;
    }

    const allPaths = paths.map(p => p.points);
    const plotterCode = pts2plotter(allPaths, a4Width, a4Height, 1);

    return {
      paths,
      plotterCode,
      a4Width,
      a4Height
    };
  };

  /**
   * 下载 PLT 文件
   */
  const downloadPltFile = (plotterCode: string) => {
    const blob = new Blob([plotterCode], { type: 'application/vnd.hp-HPGL' });
    const url = URL.createObjectURL(blob);
    const link = document.createElement('a');
    link.href = url;
    link.download = `deck-export-${new Date().toISOString().slice(0, 19).replace(/:/g, '-')}.plt`;
    document.body.appendChild(link);
    link.click();
    document.body.removeChild(link);
    URL.revokeObjectURL(url);
  };

  /**
   * 直接导出 PLT（兼容旧接口）
   */
  const exportToPlt = (pages: PageData[]) => {
    const data = generatePltData(pages);
    if (!data) {
      alert('没有可导出的卡片');
      return;
    }
    downloadPltFile(data.plotterCode);
  };

  return { generatePltData, downloadPltFile, exportToPlt };
}