smooth 0.1.1

use crate::Smooth;

/// Extension trait to consistently make multiple numbers human-readable.
// module is not public, type is re-exported
#[allow(clippy::module_name_repetitions)]
pub trait MultiSmooth {
    /// Rounds all numbers to the specified decimals.
    ///
    /// # Examples
    ///
    /// ```rust
    /// # use smooth::MultiSmooth;
    /// let mut numbers = [1.1111, 5.5555, 9.9999];
    /// numbers.round_to_mut(2);
    ///
    /// assert_eq!(numbers, [1.11, 5.56, 10.0]);
    /// ```
    fn round_to_mut(&mut self, decimals: u32);

    /// Returns formatted, consistently rounded numbers.
    ///
    /// # Examples
    ///
    /// ```rust
    /// # use smooth::MultiSmooth;
    /// let numbers = [1.1111, 5.5555, 9.9999];
    ///
    /// assert_eq!(numbers.round_to_str(2), ["1.11", "5.56", "10"]);
    /// ```
    fn round_to_str(&self, decimals: u32) -> Vec<String>;

    /// Consistently smoothes all numbers.
    ///
    /// # Examples
    ///
    /// ```rust
    /// # use smooth::MultiSmooth;
    /// let mut numbers = [1.1111, 5.5555, 9.9999];
    /// numbers.smooth_mut();
    ///
    /// assert_eq!(numbers, [1.1, 5.6, 10.0]);
    /// ```
    fn smooth_mut(&mut self);

    /// Returns formatted, consistently smoothed numbers.
    ///
    /// # Examples
    ///
    /// ```rust
    /// # use smooth::MultiSmooth;
    /// let numbers = [1.1111, 5.5555, 9.9999];
    ///
    /// assert_eq!(numbers.smooth_str(), ["1.1", "5.6", "10"]);
    /// ```
    fn smooth_str(&self) -> Vec<String>;

    #[doc(hidden)]
    fn max_td(&self) -> Option<u32>;
}

macro_rules! smooth_impl {
    ($t:ty) => {
        impl MultiSmooth for [$t] {
            fn round_to_mut(&mut self, decimals: u32) {
                for number in self.iter_mut() {
                    number.round_to_mut(decimals);
                }
            }

            fn round_to_str(&self, decimals: u32) -> Vec<String> {
                self.iter()
                    .map(|number| format!("{}", number.round_to(decimals)))
                    .collect()
            }

            fn smooth_mut(&mut self) {
                let max_td = self.max_td();

                if let Some(max_td) = max_td {
                    for number in self.iter_mut() {
                        let decimals =
                            2_u32.checked_sub(max_td).unwrap_or_default();
                        number.round_to_mut(decimals);
                    }
                }
            }

            fn smooth_str(&self) -> Vec<String> {
                let max_td = self.max_td();

                if let Some(max_td) = max_td {
                    self.iter()
                        .map(|number| {
                            let decimals =
                                2_u32.checked_sub(max_td).unwrap_or_default();
                            format!("{}", number.round_to(decimals))
                        })
                        .collect()
                } else {
                    vec![]
                }
            }

            #[doc(hidden)]
            fn max_td(&self) -> Option<u32> {
                self.iter().map(|number| number.trunc_digits()).max()
            }
        }
    };
}

smooth_impl!(f32);
smooth_impl!(f64);