use crate::commands::Command;

use crate::error::CommandError;

use crate::ui::Ui;

use hg::repo::Repo;

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

use micro_timer::timed;

use std::convert::TryFrom;

pub const HELP_TEXT: &str = "

Output the current or given revision of files

";

pub struct CatCommand<'a> {

    rev: Option<&'a str>,

    files: Vec<&'a str>,

}

impl<'a> CatCommand<'a> {

    pub fn new(rev: Option<&'a str>, files: Vec<&'a str>) -> Self {

        Self { rev, files }

    }

    fn display(&self, ui: &Ui, data: &[u8]) -> Result<(), CommandError> {

        ui.write_stdout(data)?;

        Ok(())

    }

}

impl<'a> Command for CatCommand<'a> {

    #[timed]

    fn run(&self, ui: &Ui) -> Result<(), CommandError> {

        let repo = Repo::find()?;

        repo.check_requirements()?;

        let cwd = std::env::current_dir()

            .or_else(|e| Err(CommandError::CurrentDirNotFound(e)))?;

        let mut files = vec![];

        for file in self.files.iter() {

            let normalized = cwd.join(&file);

            let stripped = normalized

                .strip_prefix(&repo.working_directory_path())

                .or(Err(CommandError::Abort(None)))?;

            let hg_file = HgPathBuf::try_from(stripped.to_path_buf())

                .or(Err(CommandError::Abort(None)))?;

            files.push(hg_file);

        }

        match self.rev {

            Some(rev) => {

                self.display(ui, &data)

            }

            None => Err(CommandError::Unimplemented.into()),

        }

    }

}