use std::error::Error;
use std::fmt;

use command_runner::CommandRunner;
use symbols::Symbol;

pub struct NpmInstall<'a> {
  target: &'a str,
  command_runner: &'a CommandRunner
}

impl<'a> NpmInstall<'a> {
  pub fn new(target: &'a str, command_runner: &'a CommandRunner) -> NpmInstall<'a> {
    NpmInstall {
      target: target,
      command_runner: command_runner
    }
  }
}

impl<'a> fmt::Display for NpmInstall<'a> {
  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
    write!(f, "npm install in {}", self.target)
  }
}

impl<'a> Symbol for NpmInstall<'a> {
  fn target_reached(&self) -> Result<bool, Box<Error>> {
    let result = try!(self.command_runner.run_with_args("sh", &["-c", &format!("cd '{}' && npm ls", self.target)]));
    Ok(result.status.success() && !String::from_utf8(result.stdout).unwrap().contains("(empty)"))
  }

  fn execute(&self) -> Result<(), Box<Error>> {
    try!(self.command_runner.run_with_args("sh", &["-c", &format!("cd '{}' && npm install --production", self.target)]));
    Ok(())
  }
}

#[cfg(test)]
mod test {
}