"use client";

import { JSX } from "react";

interface RulerProps {
  orientation: "horizontal" | "vertical";
  length: number; // mm 단위
  offset?: number; // 스크롤 오프셋 (px)
}

export function Ruler({ orientation, length, offset = 0 }: RulerProps) {
  // mm를 px로 변환 (1mm = 3.7795px, 96dpi 기준)
  const mmToPx = (mm: number) => mm * 3.7795;

  const lengthPx = mmToPx(length);
  const isHorizontal = orientation === "horizontal";

  // 눈금 생성 (10mm 단위 큰 눈금, 5mm 단위 중간 눈금, 1mm 단위 작은 눈금)
  const renderTicks = () => {
    const ticks: JSX.Element[] = [];
    const maxMm = length;

    for (let mm = 0; mm <= maxMm; mm++) {
      const px = mmToPx(mm);

      // 10mm 단위 큰 눈금
      if (mm % 10 === 0) {
        ticks.push(
          <div
            key={`major-${mm}`}
            className="absolute bg-gray-700"
            style={
              isHorizontal
                ? {
                    left: `${px}px`,
                    top: "0",
                    width: "1px",
                    height: "12px",
                  }
                : {
                    top: `${px}px`,
                    left: "0",
                    height: "1px",
                    width: "12px",
                  }
            }
          />,
        );

        // 숫자 표시 (10mm 단위)
        if (mm > 0) {
          ticks.push(
            <div
              key={`label-${mm}`}
              className="absolute text-[9px] text-gray-600"
              style={
                isHorizontal
                  ? {
                      left: `${px + 2}px`,
                      top: "0px",
                    }
                  : {
                      top: `${px + 2}px`,
                      left: "0px",
                      writingMode: "vertical-lr",
                    }
              }
            >
              {mm}
            </div>,
          );
        }
      }
      // 5mm 단위 중간 눈금
      else if (mm % 5 === 0) {
        ticks.push(
          <div
            key={`medium-${mm}`}
            className="absolute bg-gray-500"
            style={
              isHorizontal
                ? {
                    left: `${px}px`,
                    top: "4px",
                    width: "1px",
                    height: "8px",
                  }
                : {
                    top: `${px}px`,
                    left: "4px",
                    height: "1px",
                    width: "8px",
                  }
            }
          />,
        );
      }
      // 1mm 단위 작은 눈금
      else {
        ticks.push(
          <div
            key={`minor-${mm}`}
            className="absolute bg-gray-400"
            style={
              isHorizontal
                ? {
                    left: `${px}px`,
                    top: "8px",
                    width: "1px",
                    height: "4px",
                  }
                : {
                    top: `${px}px`,
                    left: "8px",
                    height: "1px",
                    width: "4px",
                  }
            }
          />,
        );
      }
    }

    return ticks;
  };

  return (
    <div
      className="relative bg-gray-100 select-none"
      style={
        isHorizontal
          ? {
              width: `${lengthPx}px`,
              height: "20px",
            }
          : {
              width: "20px",
              height: `${lengthPx}px`,
            }
      }
    >
      {renderTicks()}
    </div>
  );
}
