Add PcdUpdates and UserDiff

src/api.rs

@@ -52,7 +52,7 @@ use sdk_common::sp_client::silentpayments::{
 use sdk_common::{signature, MutexExt, MAX_PRD_PAYLOAD_SIZE};
 use serde_json::{Error as SerdeJsonError, Map, Value};
 
-use serde::{Deserialize, Serialize};
+use serde::{de, Deserialize, Serialize};
 use tsify::{JsValueSerdeExt, Tsify};
 use wasm_bindgen::convert::{FromWasmAbi, VectorFromWasmAbi};
 use wasm_bindgen::prelude::*;
@@ -96,7 +96,6 @@ pub struct ApiReturn {
     pub new_tx_to_send: Option<NewTxMessage>,
     pub ciphers_to_send: Vec<String>,
     pub commit_to_send: Option<CommitMessage>,
-    pub decrypted_pcds: HashMap<String, Value>,
 }
 
 pub type ApiResult<T: FromWasmAbi> = Result<T, ApiError>;
@@ -1572,31 +1571,53 @@ pub fn create_faucet_msg() -> ApiResult<String> {
     Ok(faucet_msg.to_string())
 }
 
+#[derive(Debug, PartialEq, Tsify, Serialize, Deserialize, Default)]
+#[tsify(into_wasm_abi)]
+#[allow(non_camel_case_types)]
+struct UserDiff {
+    new_state_merkle_root: String, // TODO add a merkle proof that the new_value belongs to that state
+    field: String,
+    previous_value: Value,
+    new_value: Value,
+    notify_user: bool,
+    need_validation: bool,
+    proof: Option<Proof>, // This is only validation (or refusal) for that specific diff, not the whole state. It can't be commited as such
+}
+
+#[derive(Debug, PartialEq, Tsify, Serialize, Deserialize, Default)]
+#[tsify(into_wasm_abi)]
+#[allow(non_camel_case_types)]
+pub struct PcdUpdates {
+    pub previous_pcd: Option<Value>, // We don't have a previous state for creation
+    pub decrypted_pcds: HashMap<String, Value>, // Key is the merkle root of the whole state
+    pub modified_values: Vec<UserDiff>, 
+}
+
 /// Get active update proposals for a given process outpoint
 /// Returns a vector with the latest commited state first, if any, and all active proposals
 #[wasm_bindgen]
-pub fn get_update_proposals(process_outpoint: String) -> ApiResult<ApiReturn> {
+pub fn get_update_proposals(process_outpoint: String) -> ApiResult<PcdUpdates> {
     let outpoint = OutPoint::from_str(&process_outpoint)?;
 
     let mut processes = lock_processes()?;
 
-    // TODO: We clone the process to prevent double borrowing issue, this can certainly be improved
     let relevant_process = processes
         .get(&outpoint)
         .ok_or(ApiError::new("process not found".to_owned()))?;
 
     let mut decrypted_pcds = HashMap::new();
+    let mut modified_values = Vec::new();
 
-    // We first push the last commited state, if any
-    match relevant_process.get_latest_commited_state() {
+    let previous_pcd = match relevant_process.get_latest_commited_state() {
         Some(state) => {
             let mut decrypted_pcd = Map::new();
-            state.encrypted_pcd.decrypt_fields(&state.keys, &mut decrypted_pcd);
-            let root = <Value as Pcd>::create_merkle_tree(&state.pcd_commitment)?.root().unwrap();
-            decrypted_pcds.insert(root.to_lower_hex_string(), Value::Object(decrypted_pcd));
+            state.encrypted_pcd.decrypt_fields(&state.pcd_commitment.to_value_object()?, &state.keys, &mut decrypted_pcd);
+            Some(Value::Object(decrypted_pcd))
         }
-        None => ()
-    }
+        None => None
+    };
+
+    let member = lock_local_device()?.to_member();
 
     for state in relevant_process.get_latest_concurrent_states()? {
         if state.encrypted_pcd == Value::Null {
@@ -1604,14 +1625,52 @@ pub fn get_update_proposals(process_outpoint: String) -> ApiResult<ApiReturn> {
             continue;
         }
 
+        let fields_to_validate = state.get_fields_to_validate_for_member(&member)?;
+
         let mut decrypted_pcd = Map::new();
-        state.encrypted_pcd.decrypt_fields(&state.keys, &mut decrypted_pcd)?;
-        let root = <Value as Pcd>::create_merkle_tree(&state.pcd_commitment)?.root().unwrap();
-        decrypted_pcds.insert(root.to_lower_hex_string(), Value::Object(decrypted_pcd));
+        state.encrypted_pcd.decrypt_fields(&state.pcd_commitment.to_value_object()?, &state.keys, &mut decrypted_pcd)?;
+        let root = state.pcd_commitment.create_merkle_tree()?.root_hex().unwrap();
+
+        if let Some(ref previous_state) = previous_pcd {
+            for (key, value) in &decrypted_pcd {
+                let previous_value = previous_state.get(key).or_else(|| Some(&Value::Null)).unwrap();
+                if previous_value == value { continue; }
+                let need_validation = if fields_to_validate.iter().any(|f| *key == **f) { true } else { false };
+                let notify_user = if need_validation { true } else if !value.is_hex_string() { true } else { false };
+                let diff = UserDiff {
+                    new_state_merkle_root: root.clone(),
+                    field: key.to_owned(),
+                    previous_value: previous_value.clone(),
+                    new_value: value.clone(),
+                    need_validation,
+                    notify_user,
+                    proof: None
+                };
+                modified_values.push(diff);
+            }
+        } else {
+            for (key, value) in &decrypted_pcd {
+                let need_validation = if fields_to_validate.iter().any(|f| *key == **f) { true } else { false };
+                let notify_user = if need_validation { true } else if !value.is_hex_string() { true } else { false };
+                let diff = UserDiff {
+                    new_state_merkle_root: root.clone(),
+                    field: key.to_owned(),
+                    previous_value: Value::Null,
+                    new_value: value.clone(),
+                    need_validation,
+                    notify_user,
+                    proof: None
+                };
+                modified_values.push(diff);
+            }
+
+        }
+        decrypted_pcds.insert(root, Value::Object(decrypted_pcd));
     }
 
-    Ok(ApiReturn {
-        decrypted_pcds,
-        ..Default::default()
+    Ok(PcdUpdates {
+        previous_pcd,
+        decrypted_pcds,   
+        modified_values,
     })
 }