ic-query 0.55.8

//! Module: report_sort
//!
//! Responsibility: sort report rows and compare common scalar view keys.
//! Does not own: report-specific sort fields, filters, or public direction models.
//! Boundary: preserves shared direction and missing-value ordering across report families.

use std::cmp::Ordering;

pub fn sort_by_optional_u64<Row>(
    rows: &mut [Row],
    descending: bool,
    key: impl Fn(&Row) -> Option<u64>,
    tiebreak: impl Fn(&Row, &Row) -> Ordering,
) {
    rows.sort_by(|left, right| {
        compare_optional_ord(key(left), key(right), descending).then_with(|| tiebreak(left, right))
    });
}

pub fn sort_by_text<Row>(
    rows: &mut [Row],
    descending: bool,
    key: impl Fn(&Row) -> &str,
    tiebreak: impl Fn(&Row, &Row) -> Ordering,
) {
    rows.sort_by(|left, right| {
        compare_ascii_case_insensitive_text(key(left), key(right), descending)
            .then_with(|| tiebreak(left, right))
    });
}

pub fn sort_by_optional_text<Row>(
    rows: &mut [Row],
    descending: bool,
    key: impl Fn(&Row) -> Option<&str>,
    tiebreak: impl Fn(&Row, &Row) -> Ordering,
) {
    rows.sort_by(|left, right| {
        compare_optional_ascii_case_insensitive_text(key(left), key(right), descending)
            .then_with(|| tiebreak(left, right))
    });
}

pub fn compare_optional_ascii_case_insensitive_text(
    left: Option<&str>,
    right: Option<&str>,
    descending: bool,
) -> Ordering {
    match (left, right) {
        (Some(left), Some(right)) => compare_ascii_case_insensitive_text(left, right, descending),
        (Some(_), None) => Ordering::Less,
        (None, Some(_)) => Ordering::Greater,
        (None, None) => Ordering::Equal,
    }
}

pub fn compare_ascii_case_insensitive_text(left: &str, right: &str, descending: bool) -> Ordering {
    let ordering = left
        .bytes()
        .map(|byte| byte.to_ascii_lowercase())
        .cmp(right.bytes().map(|byte| byte.to_ascii_lowercase()));
    if descending {
        ordering.reverse()
    } else {
        ordering
    }
}

pub fn compare_optional_ord<T>(left: Option<T>, right: Option<T>, descending: bool) -> Ordering
where
    T: Ord,
{
    match (left, right) {
        (Some(left), Some(right)) => compare_ord(left, right, descending),
        (Some(_), None) => Ordering::Less,
        (None, Some(_)) => Ordering::Greater,
        (None, None) => Ordering::Equal,
    }
}

pub fn compare_ord<T>(left: T, right: T, descending: bool) -> Ordering
where
    T: Ord,
{
    if descending {
        right.cmp(&left)
    } else {
        left.cmp(&right)
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn optional_numeric_sort_preserves_missing_keys_and_caller_id_tiebreaks() {
        let original = [
            (Some(2), Some(7)),
            (None, Some(9)),
            (Some(1), None),
            (Some(2), Some(4)),
            (Some(2), None),
        ];
        for (descending, order) in [(false, [2, 3, 0, 4, 1]), (true, [0, 3, 4, 2, 1])] {
            let mut rows = original;
            sort_by_optional_u64(
                &mut rows,
                descending,
                |row| row.0,
                |left, right| compare_optional_ord(left.1, right.1, descending),
            );
            assert_eq!(rows, order.map(|index| original[index]));
        }
    }

    #[test]
    fn text_ordering_folds_ascii_and_preserves_other_bytes() {
        for (left, right, expected) in [
            ("Alpha", "aLPHA", Ordering::Equal),
            ("", "a", Ordering::Less),
            ("A", "aa", Ordering::Less),
            ("beta", "Alpha", Ordering::Greater),
            ("_", "A", Ordering::Less),
            ("Ä", "ä", Ordering::Less),
            ("ÉA", "Éa", Ordering::Equal),
            ("z", "é", Ordering::Less),
        ] {
            assert_eq!(
                compare_ascii_case_insensitive_text(left, right, false),
                expected
            );
            assert_eq!(
                compare_ascii_case_insensitive_text(left, right, true),
                expected.reverse()
            );
        }
        for descending in [false, true] {
            assert_eq!(
                compare_optional_ascii_case_insensitive_text(Some("a"), None, descending),
                Ordering::Less
            );
            assert_eq!(
                compare_optional_ascii_case_insensitive_text(None, Some("a"), descending),
                Ordering::Greater
            );
        }
    }
}