use thiserror::Error;
use crate::api::paged::LinkHeaderParseError;
#[derive(Debug, Error)]
#[non_exhaustive]
pub enum PaginationError {
#[error("failed to parse a Link HTTP header: {}", source)]
LinkHeader {
#[from]
source: LinkHeaderParseError,
},
#[error("failed to parse a Link HTTP header URL: {}", source)]
InvalidUrl {
#[from]
source: url::ParseError,
},
}
#[derive(Debug, Default, Clone, Copy, PartialEq, Eq)]
#[non_exhaustive]
pub enum Pagination {
#[default]
All,
AllPerPageLimit(usize),
Limit(usize),
}
const MAX_PAGE_SIZE: usize = 100;
impl Pagination {
pub(crate) fn page_limit(self) -> usize {
match self {
Pagination::All => MAX_PAGE_SIZE,
Pagination::AllPerPageLimit(size) => size,
Pagination::Limit(size) => size.min(MAX_PAGE_SIZE),
}
}
pub(crate) fn is_last_page(self, last_page_size: usize, num_results: usize) -> bool {
if last_page_size < self.page_limit() {
return true;
}
if let Pagination::Limit(limit) = self {
return limit <= num_results;
}
false
}
}
#[cfg(test)]
mod tests {
use crate::api::Pagination;
#[test]
fn pagination_default() {
assert_eq!(Pagination::default(), Pagination::All);
}
#[test]
fn test_pagination_page_limit() {
assert_eq!(Pagination::All.page_limit(), super::MAX_PAGE_SIZE);
assert_eq!(
Pagination::Limit(super::MAX_PAGE_SIZE).page_limit(),
super::MAX_PAGE_SIZE,
);
assert_eq!(Pagination::Limit(1).page_limit(), 1);
assert_eq!(Pagination::AllPerPageLimit(42).page_limit(), 42);
}
}