use crate::error::CommandError;

use crate::ui::Ui;

use crate::ui::UiError;

use crate::utils::path_utils::relativize_paths;

use clap::Arg;

use hg::errors::HgError;

use hg::operations::list_rev_tracked_files;

use hg::operations::Dirstate;

use hg::repo::Repo;

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

use std::borrow::Cow;

pub const HELP_TEXT: &str = "

List tracked files.

Returns 0 on success.

";

pub fn args() -> clap::App<'static, 'static> {

    clap::SubCommand::with_name("files")

        .arg(

            Arg::with_name("rev")

                .help("search the repository as it is in REV")

                .short("-r")

                .long("--revision")

                .value_name("REV")

                .takes_value(true),

        )

        .about(HELP_TEXT)

}

pub fn run(invocation: &crate::CliInvocation) -> Result<(), CommandError> {

    let relative = invocation.config.get(b"ui", b"relative-paths");

    if relative.is_some() {

        return Err(CommandError::unsupported(

            "non-default ui.relative-paths",

        ));

    }

    let rev = invocation.subcommand_args.value_of("rev");

    let repo = invocation.repo?;

    if let Some(rev) = rev {

        let files = list_rev_tracked_files(repo, rev).map_err(|e| (e, rev))?;

        display_files(invocation.ui, repo, files.iter())

    } else {

        let distate = Dirstate::new(repo)?;

        let files = distate.tracked_files()?;

        display_files(invocation.ui, repo, files.into_iter().map(Ok))

    }

}

fn display_files<'a>(

    ui: &Ui,

    repo: &Repo,

    files: impl IntoIterator<Item = Result<&'a HgPath, HgError>>,

) -> Result<(), CommandError> {

    let mut stdout = ui.stdout_buffer();

    let mut any = false;

    relativize_paths(repo, files, |path: Cow<[u8]>| -> Result<(), UiError> {

        any = true;

        stdout.write_all(path.as_ref())?;

        stdout.write_all(b"\n")

    })?;

    stdout.flush()?;

    if any {

        Ok(())

    } else {

        Err(CommandError::Unsuccessful)

    }

}