Clamp.swift

// Copyright 2022 Yandex LLC. All rights reserved.

import CoreGraphics

@inlinable
public func clamp<T: Comparable>(
  _ value: T, min minValue: T, max maxValue: T
) -> T {
  guard minValue <= maxValue else {
    assertionFailure()
    return minValue
  }
  return value.clamp(minValue...maxValue)
}

@inlinable
public func clamp<T: FloatingPoint>(
  _ value: T, min minValue: T, max maxValue: T
) -> T
  where T.Stride: ExpressibleByFloatLiteral {
  guard minValue <= maxValue else {
    assert(minValue.isApproximatelyLessOrEqualThan(maxValue))
    return minValue
  }
  return value.clamp(minValue...maxValue)
}

public func clamp(
  _ value: CGSize, min minValue: CGSize, max maxValue: CGSize
) -> CGSize {
  CGSize(
    width: clamp(value.width, min: minValue.width, max: maxValue.width),
    height: clamp(value.height, min: minValue.height, max: maxValue.height)
  )
}

// TODO(dmt021): @_spi(Extensions)
extension Comparable {
  public func clamp(_ range: ClosedRange<Self>) -> Self {
    max(range.lowerBound, min(range.upperBound, self))
  }
}

// TODO(dmt021): @_spi(Extensions)
extension Comparable where Self: Strideable, Self.Stride: SignedInteger {
  public func clamp(_ range: Range<Self>) -> Self? {
    guard !range.isEmpty else {
      return nil
    }
    return clamp(ClosedRange(range))
  }
}