fingerprintjs

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const maxValueToCheck = 100
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/**
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 * If the display is monochrome (e.g. black&white), the value will be ≥0 and will mean the number of bits per pixel.
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 * If the display is not monochrome, the returned value will be 0.
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 * If the browser doesn't support this feature, the returned value will be undefined.
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 *
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 * @see https://developer.mozilla.org/en-US/docs/Web/CSS/@media/monochrome
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 */
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export default function getMonochromeDepth(): number | undefined {
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  if (!matchMedia('(min-monochrome: 0)').matches) {
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    // The media feature isn't supported by the browser
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    return undefined
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  }
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  // A variation of binary search algorithm can be used here.
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  // But since expected values are very small (≤10), there is no sense in adding the complexity.
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  for (let i = 0; i <= maxValueToCheck; ++i) {
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    if (matchMedia(`(max-monochrome: ${i})`).matches) {
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      return i
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    }
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  }
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  throw new Error('Too high value')
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}
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