// list_tracked_files.rs

//

// Copyright 2020 Antoine Cezar <antoine.cezar@octobus.net>

//

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

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

use crate::dirstate::parsers::parse_dirstate_entries;

use crate::dirstate_tree::on_disk::{for_each_tracked_path, read_docket};

use crate::errors::HgError;

use crate::repo::Repo;

use crate::revlog::node::Node;

use crate::revlog::revlog::RevlogError;

use crate::utils::hg_path::HgPath;

use crate::DirstateError;

use rayon::prelude::*;

/// List files under Mercurial control in the working directory

/// by reading the dirstate

pub struct Dirstate {

    /// The `dirstate` content.

    content: Vec<u8>,

    v2_metadata: Option<Vec<u8>>,

}

impl Dirstate {

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

        let mut content = repo.hg_vfs().read("dirstate")?;

        let v2_metadata = if repo.has_dirstate_v2() {

            let docket = read_docket(&content)?;

            let meta = docket.tree_metadata().to_vec();

            content = repo.hg_vfs().read(docket.data_filename())?;

            Some(meta)

        } else {

            None

        };

        Ok(Self {

            content,

            v2_metadata,

        })

    }

    pub fn tracked_files(&self) -> Result<Vec<&HgPath>, DirstateError> {

        let mut files = Vec::new();

        if !self.content.is_empty() {

            if let Some(meta) = &self.v2_metadata {

                for_each_tracked_path(&self.content, meta, |path| {

                    files.push(path)

                })?

            } else {

                let _parents = parse_dirstate_entries(

                    &self.content,

                    |path, entry, _copy_source| {

                        if entry.state.is_tracked() {

                            files.push(path)

                        }

                        Ok(())

                    },

                )?;

            }

        }

        files.par_sort_unstable();

        Ok(files)

    }

}

/// List files under Mercurial control at a given revision.

pub fn list_rev_tracked_files(

    repo: &Repo,

    revset: &str,

) -> Result<FilesForRev, RevlogError> {

    let rev = crate::revset::resolve_single(revset, repo)?;

    let changelog_entry = changelog.get_rev(rev)?;

    let manifest_node =

        Node::from_hex_for_repo(&changelog_entry.manifest_node()?)?;

    let manifest_entry = manifest.get_node(manifest_node.into())?;

    Ok(FilesForRev(manifest_entry))

}

pub struct FilesForRev(Manifest);

impl FilesForRev {

    pub fn iter(&self) -> impl Iterator<Item = &HgPath> {

        self.0.files()

    }

}