use std::cmp::Ordering;

use git_object::bstr::BString;
use git_repository as git;
use git_repository::{
    config::tree::{Core, Key},
    prelude::ObjectIdExt,
};

/// Convert a hexadecimal hash into its corresponding `ObjectId` or _panic_.
fn hex_to_id(hex: &str) -> git_hash::ObjectId {
    git_hash::ObjectId::from_hex(hex.as_bytes()).expect("40 bytes hex")
}

#[test]
fn prefix() -> crate::Result {
    let repo = crate::repo("make_repo_with_fork_and_dates.sh")?.to_thread_local();
    let work_dir = repo.work_dir().expect("non-bare");
    let id = hex_to_id("288e509293165cb5630d08f4185bdf2445bf6170").attach(&repo);
    let prefix = id.shorten()?;
    assert_eq!(prefix.cmp_oid(&id), Ordering::Equal);
    assert_eq!(prefix.hex_len(), 7, "preconfigured via core.abbrev default value");

    let repo = git::open_opts(
        work_dir,
        git::open::Options::isolated().config_overrides(Core::ABBREV.validated_assignment("5".into())),
    )
    .unwrap();
    let id = id.detach().attach(&repo);
    let prefix = id.shorten()?;
    assert_eq!(prefix.cmp_oid(&id), Ordering::Equal);
    assert_eq!(prefix.hex_len(), 5, "preconfigured via core.abbrev");

    assert!(
        git::open_opts(
            work_dir,
            git::open::Options::isolated().config_overrides(Some(BString::from("core.abbrev=invalid")))
        )
        .is_ok(),
        "By default gitoxide acts like `libgit2` here and we prefer to be lenient when possible"
    );

    assert!(
        matches!(
            git::open_opts(
                work_dir,
                git::open::Options::isolated()
                    .strict_config(true)
                    .config_overrides(Some(BString::from("core.abbrev=invalid")))
            )
            .unwrap_err(),
            git::open::Error::Config(git::config::Error::CoreAbbrev(_))
        ),
        "an empty core.abbrev fails the open operation in strict config mode, emulating git behaviour"
    );
    Ok(())
}

#[test]
fn display_and_debug() -> crate::Result {
    let repo = crate::basic_repo()?;
    let id = repo.head_id()?;
    assert_eq!(
        format!("{} {:?}", id, id),
        "3189cd3cb0af8586c39a838aa3e54fd72a872a41 Sha1(3189cd3cb0af8586c39a838aa3e54fd72a872a41)"
    );
    Ok(())
}

mod ancestors {
    use git_traverse::commit;

    #[test]
    fn all() -> crate::Result {
        let repo = crate::repo("make_repo_with_fork_and_dates.sh")?.to_thread_local();
        let head = repo.head()?.into_fully_peeled_id().expect("born")?;
        let commits_graph_order = head.ancestors().all()?.collect::<Result<Vec<_>, _>>()?;
        assert_eq!(commits_graph_order.len(), 4, "need a specific amount of commits");

        let commits_by_commit_date = head
            .ancestors()
            .sorting(commit::Sorting::ByCommitTimeNewestFirst)
            .all()?
            .collect::<Result<Vec<_>, _>>()?;
        assert_eq!(
            commits_by_commit_date.len(),
            4,
            "need a specific amount of commits, ordering doesn't affect that"
        );
        assert_ne!(
            commits_by_commit_date, commits_graph_order,
            "these are ordered differently"
        );

        assert_eq!(
            head.ancestors().first_parent_only().all()?.count(),
            3,
            "It skips merges this way."
        );
        Ok(())
    }
}