use std::path::Path;

pub fn is_on_system_drive(path: &Path) -> bool {
    let Some(system_drive) = std::env::var_os("SystemDrive") else {
        return false;
    };
    let system_drive = system_drive.to_string_lossy().to_ascii_lowercase();
    let path_text = path.as_os_str().to_string_lossy().to_ascii_lowercase();
    path_text.starts_with(&system_drive)
}

pub fn system_drive_warning(path: &Path) -> Option<&'static str> {
    if is_on_system_drive(path) {
        Some(
            "当前数据位置位于Windows系统盘。帖子数据库、图片和视频可能持续增长，建议使用空间较充足的非系统盘。",
        )
    } else {
        None
    }
}

#[cfg(test)]
mod tests {
    use std::path::Path;

    use super::is_on_system_drive;

    #[test]
    fn detects_system_drive_prefix_without_panicking() {
        let _ = is_on_system_drive(Path::new("C:\\example"));
    }
}