use std::fs;
use std::path::Path;
use std::process::ExitCode;
use std::time::{Duration, SystemTime};

const ONE_WEEK: Duration = Duration::from_secs(7 * 24 * 60 * 60);

pub fn run(dir: &str) -> ExitCode {
    let entries = match fs::read_dir(Path::new(dir)) {
        Ok(e) => e,
        Err(e) => {
            eprintln!("estampa: cannot read directory '{dir}': {e}");
            return ExitCode::from(1);
        }
    };

    let now = SystemTime::now();
    let mut had_error = false;

    for entry in entries {
        let entry = match entry {
            Ok(e) => e,
            Err(e) => {
                eprintln!("estampa: cannot read directory entry: {e}");
                had_error = true;
                continue;
            }
        };

        let path = entry.path();

        // symlink_metadata so we never follow links out of the dir
        let metadata = match entry.path().symlink_metadata() {
            Ok(m) => m,
            Err(e) => {
                eprintln!("estampa: cannot stat '{}': {e}", path.display());
                had_error = true;
                continue;
            }
        };

        if !metadata.is_file() {
            continue;
        }

        let modified = match metadata.modified() {
            Ok(m) => m,
            Err(e) => {
                eprintln!("estampa: cannot read mtime for '{}': {e}", path.display());
                had_error = true;
                continue;
            }
        };

        let Ok(age) = now.duration_since(modified) else {
            continue;
        };

        if age > ONE_WEEK
            && let Err(e) = fs::remove_file(&path)
        {
            eprintln!("estampa: cannot remove '{}': {e}", path.display());
            had_error = true;
        }
    }

    if had_error {
        ExitCode::from(1)
    } else {
        ExitCode::SUCCESS
    }
}