export function calcLinearColor()

in src/common/common.ts [823:902]
68 lines of code
12 McCabe index (conditional complexity)

export function calcLinearColor(primaryColor: string, backgroundColor?: string, linearCount?: number, type?: string, needDistribution?: boolean) {
  const linear = [];
  const front = tinycolor(primaryColor);
  const { h, s, v } = front.toHsv();
  const { v: backValue } = tinycolor(backgroundColor).toHsv();
  const isLight = backValue > 0.5;
  const whiteV = tinycolor("#ffffff").toHsv().v;

  const count = linearCount + 1;

  // 中心取色逻辑
  if (type === 'center') {
    let colorString;
    for (let i = 1; i < count + 1; i++) {
      colorString = tinycolor({
        h,
        s: Math.round((i * s * 100) / count) + 1,
        v: Math.round(((i * (v - whiteV)) / count + whiteV) * 100),
      }).toHexString();

      if (i % 2 === 0) {
        linear.push(colorString);
      } else if (colorString === primaryColor) {
        linear.push(colorString);
      }
    }

    for (let i = count; i > Math.floor(count/ 2) + 1; i--) {
      colorString = tinycolor.mix("#000000", primaryColor, (i - 2) * 10).toHexString();
      linear.push(colorString);
    }

    if (linear[Math.floor(linearCount / 2)] !== primaryColor) {
      linear[Math.floor(linearCount / 2)] = primaryColor;
    }
  } else {
    // 如果数量超过10，则有限调整前5的颜色梯度差值，避免过于相近
    // 同时需要防止颜色过于趋向于白/黑
    if (needDistribution) {
      const distributionArray = generateScaledArray(count);

      // console.log(distributionArray)
      for (let i = count - 1; i > 0; i--) {
        let colorString;
        // 亮色模式
        if (isLight) {
          colorString = tinycolor({
            h,
            s: distributionArray[count - i - 1] * s * 100,
            // v: v * 100,
            v: Math.round(((i * (v - backValue)) / count + backValue) * 100),
          }).toHexString();
        } else {
          // 暗色模式
          colorString = tinycolor.mix(backgroundColor, primaryColor, distributionArray[count - i - 1] * 100).toHexString();
        }

        linear.push(colorString);
      }
    } else {
      for (let i = count - 1; i > 0; i--) {
        let colorString;
        // 亮色模式
        if (isLight) {
          colorString = tinycolor({
            h,
            s: Math.round((i / count) * s * 100),
            v: Math.round(((i * (v - backValue)) / count + backValue) * 100),
          }).toHexString();
        } else {
          // 暗色模式
          colorString = tinycolor.mix(backgroundColor, primaryColor, i * 10).toHexString();
        }
        linear.push(colorString);
      }
    }
  }

  return linear;
}