#[derive(Debug)]
pub struct TokenError {
    pub msg: String,
}

impl TokenError {
    pub fn new(msg: &str) -> TokenError {
        TokenError { msg: msg.to_string() }
    }
}

#[derive(Debug)]
pub struct ParseError {
    pub msg: String,
}

pub struct LLVMCodeString(pub String);

#[derive(Debug, Default)]
pub struct EvalOptions {
  pub debug_tokens: bool,
  pub debug_parse: bool,
  pub debug_type: bool,
  pub trace_evaluation: bool,
}

#[derive(Debug, Default)]
pub struct ReplOutput {
  output: String,
  artifacts: Vec<TraceArtifact>
}

impl ReplOutput {
  pub fn add_artifact(&mut self, artifact: TraceArtifact) {
    self.artifacts.push(artifact);
  }
  pub fn add_output(&mut self, output: String) {
    self.output = output;
  }

  pub fn to_string(&self) -> String {
    let mut acc = String::new();
    for line in self.artifacts.iter() {
      acc.push_str(&line.debug_output);
    }
    acc.push_str(&self.output);
    acc
  }

  pub fn print_to_screen(&self) {
    for line in self.artifacts.iter() {
      println!("{}: {}", line.stage_name, line.debug_output);
    }
    println!("{}", self.output);
  }
}

/*
//TODO I'll probably wanna implement this later
#[derive(Debug)]
pub struct CompilationOutput {
  output: LLVMCodeString,
  artifacts: Vec<TraceArtifact>,
}
*/

#[derive(Debug)]
pub struct TraceArtifact {
  stage_name: String,
  debug_output: String,
}

impl TraceArtifact {
  pub fn new(stage: &str, debug: String) -> TraceArtifact {
    TraceArtifact { stage_name: stage.to_string(), debug_output: debug }
  }
}

pub trait ProgrammingLanguageInterface {
  fn evaluate_in_repl(&mut self, input: &str, eval_options: EvalOptions) -> ReplOutput;
  fn get_language_name(&self) -> String;
  fn compile(&mut self, _input: &str) -> LLVMCodeString {
    LLVMCodeString("".to_string())
  }
  fn can_compile(&self) -> bool {
    false
  }
}