use std::fmt;

use itertools::{Itertools, Position};

pub struct PrintList<'a, I: Iterator<Item = E> + Clone, E: fmt::Display>(pub I, pub &'a str);
impl<'a, I: Iterator<Item = E> + Clone, E: fmt::Display> fmt::Display for PrintList<'a, I, E> {
	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
		for (pos, item) in self.0.clone().with_position() {
			match pos {
				Position::First | Position::Only => write!(f, "{item}")?,
				Position::Middle => write!(f, ", {item}")?,
				Position::Last => write!(f, ", {} {item}", self.1)?,
			}
		}
		Ok(())
	}
}

pub trait IteratorPrint: Iterator<Item: fmt::Display> + Clone {
	/// Pretty-print a list with a comma-separated enumeration and an operator
	/// word (such as "and" or "or") inserted before the last
	fn display<'a>(self, operator: &'a str) -> PrintList<'a, Self, Self::Item> {
		PrintList(self, operator)
	}
}
impl<T: Iterator<Item: fmt::Display> + Clone> IteratorPrint for T {}