// path utils module

//

// This software may be used and distributed according to the terms of the

// GNU General Public License version 2 or any later version.

use hg::errors::HgError;

use hg::repo::Repo;

use hg::utils::current_dir;

use hg::utils::files::{get_bytes_from_path, relativize_path};

use hg::utils::hg_path::HgPath;

use hg::utils::hg_path::HgPathBuf;

use std::borrow::Cow;

pub struct RelativizePaths {

    repo_root: HgPathBuf,

    cwd: HgPathBuf,

    outside_repo: bool,

}

impl RelativizePaths {

    pub fn new(repo: &Repo) -> Result<Self, HgError> {

        let cwd = current_dir()?;

        let repo_root = repo.working_directory_path();

        let repo_root = cwd.join(repo_root); // Make it absolute

        let repo_root_hgpath =

            HgPathBuf::from(get_bytes_from_path(&repo_root));

        if let Ok(cwd_relative_to_repo) = cwd.strip_prefix(&repo_root) {

            // The current directory is inside the repo, so we can work with

            // relative paths

            Ok(Self {

                repo_root: repo_root_hgpath,

                cwd: HgPathBuf::from(get_bytes_from_path(

                    cwd_relative_to_repo,

                )),

                outside_repo: false,

            })

        } else {

            Ok(Self {

                repo_root: repo_root_hgpath,

                cwd: HgPathBuf::from(get_bytes_from_path(cwd)),

                outside_repo: true,

            })

        }

    }

    pub fn relativize<'a>(&self, path: &'a HgPath) -> Cow<'a, [u8]> {

        if self.outside_repo {

            let joined = self.repo_root.join(path);

            Cow::Owned(relativize_path(&joined, &self.cwd).into_owned())

        } else {

            relativize_path(path, &self.cwd)

        }

    }

}