use asn1::Tag;
use openssl::asn1::{Asn1Object, Asn1OctetString};
use openssl::x509::X509Extension;

pub struct CRLDistributionPointExt {
    pub url: String,
}

impl CRLDistributionPointExt {
    pub fn as_extension(&self) -> anyhow::Result<X509Extension> {
        let crl_obj = Asn1Object::from_str("2.5.29.31")?;

        let tag_a0 = Tag::from_bytes(&[0xa0]).unwrap().0;
        let tag_86 = Tag::from_bytes(&[0x86]).unwrap().0;

        let crl_bytes = asn1::write(|w| {
            w.write_element(&asn1::SequenceWriter::new(&|w| {
                w.write_element(&asn1::SequenceWriter::new(&|w| {
                    w.write_tlv(tag_a0, |w| {
                        w.push_slice(&asn1::write(|w| {
                            w.write_tlv(tag_a0, |w| {
                                w.push_slice(&asn1::write(|w| {
                                    w.write_tlv(tag_86, |b| b.push_slice(self.url.as_bytes()))?;
                                    Ok(())
                                })?)
                            })?;

                            Ok(())
                        })?)
                    })?;
                    Ok(())
                }))?;
                Ok(())
            }))
        })?;

        Ok(X509Extension::new_from_der(
            crl_obj.as_ref(),
            false,
            Asn1OctetString::new_from_bytes(&crl_bytes)?.as_ref(),
        )?)
    }
}