From aaa0d85a55e35f95a9f7a3eda97a0d03614e16ac Mon Sep 17 00:00:00 2001
From: thefireskater <114769322+thefireskater@users.noreply.github.com>
Date: Fri, 2 Jun 2023 23:14:30 -0700
Subject: [PATCH] Given selectors, return n-quad positions

---
 ssi-jws/src/lib.rs   |  4 ++++
 ssi-ldp/src/lib.rs   | 11 +++++++++++
 ssi-ldp/src/proof.rs |  1 +
 ssi-vc/src/lib.rs    | 22 ++++++++++++++++++++++
 4 files changed, 38 insertions(+)

diff --git a/ssi-jws/src/lib.rs b/ssi-jws/src/lib.rs
index 805c9a002..094eb22f5 100644
--- a/ssi-jws/src/lib.rs
+++ b/ssi-jws/src/lib.rs
@@ -357,6 +357,8 @@ pub fn verify_payload(
                             assert!(credential_subject_id != "", "credentialSubject node not found");
 
                             let mut first_claim_found = false;
+
+                            i = 0;
                             while i < payload.messages.len() {
                                 let m = payload.messages[i].as_str();
                                 if m.starts_with(credential_subject_id) {
@@ -368,9 +370,11 @@ pub fn verify_payload(
                             assert!(first_claim_found, "No claims in derived credential");
 
                             for j in 0..message_hashes.len() {
+                                //eprintln!("Checking hash for {}: ", payload.messages[i].as_str());
                                 let revealed_hash = message_hashes[j];
                                 let target_hash = SignatureMessage::hash(payload.messages[i].as_bytes());
                                 if revealed_hash != target_hash {
+                                    //eprintln!("Hashes do not match");
                                     return Err(Error::InvalidSignature);
                                 }
 
diff --git a/ssi-ldp/src/lib.rs b/ssi-ldp/src/lib.rs
index 5dc29f91c..132034f59 100644
--- a/ssi-ldp/src/lib.rs
+++ b/ssi-ldp/src/lib.rs
@@ -648,6 +648,17 @@ fn rename_blank_node_labels(orig: &Vec<String>) -> Vec<String> {
     rewritten
 }
 
+pub async fn to_nquads(
+    document: &(dyn LinkedDataDocument + Sync),
+    context_loader: &mut ContextLoader,
+) -> Result<Vec<String>, Error> {
+    let doc_dataset = document
+        .to_dataset_for_signing(None, context_loader)
+        .await?;
+    let doc_normalized = urdna2015::normalize(doc_dataset.quads().map(QuadRef::from)).into_nquads_vec();
+    Ok(doc_normalized)
+}
+
 async fn to_jws_payload_v2(
     document: &(dyn LinkedDataDocument + Sync),
     proof: &Proof,
diff --git a/ssi-ldp/src/proof.rs b/ssi-ldp/src/proof.rs
index c9cc17bbf..a9a6616b8 100644
--- a/ssi-ldp/src/proof.rs
+++ b/ssi-ldp/src/proof.rs
@@ -223,6 +223,7 @@ pub struct LinkedDataProofOptions {
     #[serde(skip_serializing_if = "Option::is_none")]
     /// The nonce of the proof.
     pub nonce: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     /// Indices of disclosed messages
     pub disclosed_message_indices: Option<Vec<usize>>,
     #[serde(skip_serializing_if = "Option::is_none")]
diff --git a/ssi-vc/src/lib.rs b/ssi-vc/src/lib.rs
index fb5a00796..3e735e828 100644
--- a/ssi-vc/src/lib.rs
+++ b/ssi-vc/src/lib.rs
@@ -984,6 +984,7 @@ impl Credential {
         resolver: &dyn DIDResolver,
         context_loader: &mut ContextLoader,
     ) -> VerificationResult {
+        // this is the entrypoint called by didkit
         let nonce = match options.as_ref() {
             Some(ldp_options) => ldp_options.nonce.clone(),
             None => None
@@ -1096,6 +1097,27 @@ impl Credential {
         result.checks.push(Check::Status);
         result
     }
+
+    pub async fn get_nquad_positions(&self, selectors: &Vec<String>, context_loader: &mut ContextLoader) -> Result<Vec<u32>, Error> {
+        let nquads = ssi_ldp::to_nquads(self, context_loader).await?;
+        let mut positions = Vec::new();
+        let mut index: u32 = 2;
+        for nq in nquads.iter() {
+            let split: Vec<&str> = nq.split(" ").collect();
+            let middle = split[1];
+
+            for s in selectors.iter() {
+                let suffix = "/".to_owned() + s + ">";
+                if middle.ends_with(suffix.as_str()) {
+                    positions.push(index);
+                    break;
+                }
+            }
+
+            index += 1;
+        }
+        Ok(positions)
+    }
 }
 
 impl CheckableStatus {