use crate::compose::Environment;
use crate::poem::Verse;
use crate::poem::{read::Readable, recite::Reciteable, Poem};
use std::fs;

/// source
///
/// The builtin `source` command. Used to change the shell's global environment
/// state via a `.sh` or `.dwvsh` file.
///
/// # Shell Examples
/// ```sh
/// source ~/.dwvshrc
/// ```
pub fn incant(verse: &Verse, out: &mut Vec<u8>, env: &mut Environment) -> i32 {
    let files = match verse.clause() {
        Some(clause) => clause,
        None => {
            eprintln!("source: not enough arguments");
            return 1;
        }
    };

    for file in files {
        let poetry = match fs::read_to_string(&file) {
            Ok(poetry) => poetry,
            Err(e) => {
                eprintln!(
                    "source: could not load {}: {}",
                    file,
                    e.to_string().to_lowercase()
                );
                return 127;
            }
        };

        let poem = match Poem::read(poetry, env) {
            Ok(poem) => poem,
            Err(e) => {
                eprintln!("dwvsh: {}", e.to_string().to_lowercase());
                continue;
            }
        };

        let stdout = if verse.couplet { Some(true) } else { None };

        *out = match poem.recite(env, stdout) {
            Ok(out) => out,
            Err(e) => {
                eprintln!("dwvsh: {}", e.to_string().to_lowercase());
                continue;
            }
        };
    }

    0
}