use std::fs;
use std::os::unix::fs::MetadataExt;
use std::path::Path;

/// Reads the file and strips whitespace (including newlines)
/// Useful for file-based key-value store
pub fn read_or_none(path: &Path) -> Option<String> {
    if !path.is_file() {
        return None;
    }
    match fs::read_to_string(path) {
        Ok(content) => {
            // Remove trailing space/newlines
            Some(content.trim().to_string())
        }
        Err(e) => {
            eprintln!("IO ERROR: {}", e);
            None
        }
    }
}

pub fn read_extension(path: &Path, setting: &str) -> Option<String> {
    let mut path = path.to_path_buf();
    path.set_extension(setting);
    read_or_none(&path)
}

/// Returns true when the file exists and has user exec
/// permission. Returns false otherwise.
pub fn is_executable(path: &Path) -> bool {
    // Do not match directories
    if !path.is_file() {
        return false;
    }
    match fs::metadata(path) {
        Ok(stat) => {
            let mode = stat.mode();
            // Check user exec permission)
            if (mode & 0o100) == 0o100 {
                true
            } else {
                false
            }
        }
        Err(e) => {
            eprintln!("IO Error: {}", e);
            false
        }
    }
}