Implement multi-signature escrow contract with client, freelancer, an…

contracts/contracts/escrow/src/lib.rs

@@ -33,6 +33,8 @@ pub enum DataKey {
     Token,
     Milestones,
     IsFunded,
+    ClientApproval(u32),
+    FreelancerApproval(u32),
 }
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
@@ -46,6 +48,8 @@ pub enum Error {
     InvalidMilestoneStatus = 6,
     Unauthorized = 7,
     ZeroAmount = 8,
+    InsufficientApprovals = 9,
+    AlreadyApproved = 10,
 }
 
 #[contract]
@@ -165,6 +169,12 @@ impl EscrowContract {
         let client: Address = env.storage().instance().get(&DataKey::Client).ok_or(Error::NotInitialized)?;
         client.require_auth();
 
+        // Check if already approved by client
+        let approval_key = DataKey::ClientApproval(milestone_id);
+        if env.storage().instance().has(&approval_key) {
+            return Err(Error::AlreadyApproved);
+        }
+
         let milestones: Vec<Milestone> = env.storage().instance().get(&DataKey::Milestones).ok_or(Error::NotInitialized)?;
         let mut found = false;
         let mut updated_milestones = Vec::new(&env);
@@ -176,6 +186,8 @@ impl EscrowContract {
                 if milestone.status != MilestoneStatus::Submitted {
                     return Err(Error::InvalidMilestoneStatus);
                 }
+                // Set client approval
+                env.storage().instance().set(&approval_key, &true);
                 milestone.status = MilestoneStatus::Approved;
             }
             updated_milestones.push_back(milestone);
@@ -189,8 +201,41 @@ impl EscrowContract {
         Ok(())
     }
 
+    /// Freelancer confirms milestone completion (second signature for multi-sig release).
+    pub fn freelancer_confirm(env: Env, milestone_id: u32) -> Result<(), Error> {
+        let freelancer: Address = env.storage().instance().get(&DataKey::Freelancer).ok_or(Error::NotInitialized)?;
+        freelancer.require_auth();
+
+        let milestones: Vec<Milestone> = env.storage().instance().get(&DataKey::Milestones).ok_or(Error::NotInitialized)?;
+        let mut found = false;
+
+        for i in 0..milestones.len() {
+            let milestone = milestones.get(i).unwrap();
+            if milestone.id == milestone_id {
+                found = true;
+                if milestone.status != MilestoneStatus::Approved {
+                    return Err(Error::InvalidMilestoneStatus);
+                }
+                // Check if already confirmed by freelancer
+                let approval_key = DataKey::FreelancerApproval(milestone_id);
+                if env.storage().instance().has(&approval_key) {
+                    return Err(Error::AlreadyApproved);
+                }
+                // Set freelancer confirmation
+                env.storage().instance().set(&approval_key, &true);
+            }
+        }
+
+        if !found {
+            return Err(Error::MilestoneNotFound);
+        }
+
+        Ok(())
+    }
+
     /// Transfers funds of an approved milestone to the freelancer.
-    /// Can be triggered by either client or freelancer.
+    /// Requires multi-signature: both client and freelancer must have approved.
+    /// Can be triggered by either client or freelancer after both approvals.
     pub fn release(env: Env, milestone_id: u32, caller: Address) -> Result<(), Error> {
         caller.require_auth();
 
@@ -201,6 +246,17 @@ impl EscrowContract {
             return Err(Error::Unauthorized);
         }
 
+        // Check multi-signature requirement: both client and freelancer must have approved
+        let client_approval_key = DataKey::ClientApproval(milestone_id);
+        let freelancer_approval_key = DataKey::FreelancerApproval(milestone_id);
+
+        let client_approved: bool = env.storage().instance().get(&client_approval_key).unwrap_or(false);
+        let freelancer_approved: bool = env.storage().instance().get(&freelancer_approval_key).unwrap_or(false);
+
+        if !client_approved || !freelancer_approved {
+            return Err(Error::InsufficientApprovals);
+        }
+
         let milestones: Vec<Milestone> = env.storage().instance().get(&DataKey::Milestones).ok_or(Error::NotInitialized)?;
         let mut found = false;
         let mut transfer_amount: i128 = 0;
@@ -276,6 +332,7 @@ impl EscrowContract {
 
     /// Puts a milestone into dispute, halting regular flow and delegating resolution to the arbiter.
     /// Can be raised by client or freelancer.
+    /// Clears any existing approvals when dispute is raised.
     pub fn dispute(env: Env, milestone_id: u32, caller: Address) -> Result<(), Error> {
         caller.require_auth();
 
@@ -294,10 +351,13 @@ impl EscrowContract {
             let mut milestone = milestones.get(i).unwrap();
             if milestone.id == milestone_id {
                 found = true;
-                if milestone.status != MilestoneStatus::Funded && milestone.status != MilestoneStatus::Submitted {
+                if milestone.status != MilestoneStatus::Funded && milestone.status != MilestoneStatus::Submitted && milestone.status != MilestoneStatus::Approved {
                     return Err(Error::InvalidMilestoneStatus);
                 }
                 milestone.status = MilestoneStatus::Disputed;
+                // Clear approvals when dispute is raised
+                env.storage().instance().remove(&DataKey::ClientApproval(milestone_id));
+                env.storage().instance().remove(&DataKey::FreelancerApproval(milestone_id));
             }
             updated_milestones.push_back(milestone);
         }
@@ -381,6 +441,16 @@ impl EscrowContract {
     pub fn is_funded(env: Env) -> bool {
         env.storage().instance().get(&DataKey::IsFunded).unwrap_or(false)
     }
+
+    /// Check if client has approved a specific milestone
+    pub fn has_client_approval(env: Env, milestone_id: u32) -> bool {
+        env.storage().instance().get(&DataKey::ClientApproval(milestone_id)).unwrap_or(false)
+    }
+
+    /// Check if freelancer has approved a specific milestone
+    pub fn has_freelancer_approval(env: Env, milestone_id: u32) -> bool {
+        env.storage().instance().get(&DataKey::FreelancerApproval(milestone_id)).unwrap_or(false)
+    }
 }
 
 mod test;

contracts/contracts/escrow/src/test.rs

@@ -99,11 +99,16 @@ fn test_happy_path() {
     escrow.submit_milestone(&1);
     assert_eq!(escrow.get_milestones().get(0).unwrap().status, MilestoneStatus::Submitted);
 
-    // Approve Milestone 1
+    // Approve Milestone 1 by client
     escrow.approve(&1);
     assert_eq!(escrow.get_milestones().get(0).unwrap().status, MilestoneStatus::Approved);
+    assert_eq!(escrow.has_client_approval(&1), true);
 
-    // Release Milestone 1 by freelancer
+    // Freelancer confirms Milestone 1 (multi-sig requirement)
+    escrow.freelancer_confirm(&1);
+    assert_eq!(escrow.has_freelancer_approval(&1), true);
+
+    // Release Milestone 1 by freelancer (now both approvals are present)
     escrow.release(&1, &setup.freelancer);
     assert_eq!(escrow.get_milestones().get(0).unwrap().status, MilestoneStatus::Released);
 
@@ -159,6 +164,7 @@ fn test_dispute_and_resolve_to_freelancer() {
     escrow.initialize(&setup.client, &setup.freelancer, &setup.arbiter, &setup.token_address, &milestones);
     escrow.fund();
     escrow.submit_milestone(&1);
+    escrow.approve(&1);
 
     // Client disputes the milestone
     escrow.dispute(&1, &setup.client);
@@ -190,6 +196,7 @@ fn test_dispute_and_resolve_to_client() {
 
     escrow.initialize(&setup.client, &setup.freelancer, &setup.arbiter, &setup.token_address, &milestones);
     escrow.fund();
+    escrow.submit_milestone(&1);
 
     // Freelancer disputes milestone (perhaps client won't approve)
     escrow.dispute(&1, &setup.freelancer);
@@ -262,8 +269,112 @@ fn test_unauthorized_release_fails() {
     escrow.fund();
     escrow.submit_milestone(&1);
     escrow.approve(&1);
+    escrow.freelancer_confirm(&1);
 
     // Random address tries to trigger release
     let stranger = Address::generate(&env);
     escrow.release(&1, &stranger);
 }
+
+#[test]
+#[should_panic(expected = "HostError: Error(Contract, #9)")]
+fn test_release_without_both_approvals_fails() {
+    let setup = setup_test();
+    let escrow = setup.escrow_client;
+    let env = setup.env;
+
+    let milestone = Milestone {
+        id: 1,
+        amount: 100,
+        status: MilestoneStatus::Pending,
+        description: String::from_str(&env, "Milestone"),
+    };
+    let milestones = vec![&env, milestone];
+
+    escrow.initialize(&setup.client, &setup.freelancer, &setup.arbiter, &setup.token_address, &milestones);
+    escrow.fund();
+    escrow.submit_milestone(&1);
+    escrow.approve(&1);
+    // Missing freelancer_confirm - should fail with InsufficientApprovals (error code 9)
+    escrow.release(&1, &setup.client);
+}
+
+#[test]
+#[should_panic(expected = "HostError: Error(Contract, #10)")]
+fn test_double_client_approval_fails() {
+    let setup = setup_test();
+    let escrow = setup.escrow_client;
+    let env = setup.env;
+
+    let milestone = Milestone {
+        id: 1,
+        amount: 100,
+        status: MilestoneStatus::Pending,
+        description: String::from_str(&env, "Milestone"),
+    };
+    let milestones = vec![&env, milestone];
+
+    escrow.initialize(&setup.client, &setup.freelancer, &setup.arbiter, &setup.token_address, &milestones);
+    escrow.fund();
+    escrow.submit_milestone(&1);
+    escrow.approve(&1);
+    // Double approval should fail with AlreadyApproved (error code 10)
+    escrow.approve(&1);
+}
+
+#[test]
+#[should_panic(expected = "HostError: Error(Contract, #10)")]
+fn test_double_freelancer_confirmation_fails() {
+    let setup = setup_test();
+    let escrow = setup.escrow_client;
+    let env = setup.env;
+
+    let milestone = Milestone {
+        id: 1,
+        amount: 100,
+        status: MilestoneStatus::Pending,
+        description: String::from_str(&env, "Milestone"),
+    };
+    let milestones = vec![&env, milestone];
+
+    escrow.initialize(&setup.client, &setup.freelancer, &setup.arbiter, &setup.token_address, &milestones);
+    escrow.fund();
+    escrow.submit_milestone(&1);
+    escrow.approve(&1);
+    escrow.freelancer_confirm(&1);
+    // Double confirmation should fail with AlreadyApproved (error code 10)
+    escrow.freelancer_confirm(&1);
+}
+
+#[test]
+fn test_dispute_clears_approvals() {
+    let setup = setup_test();
+    let escrow = setup.escrow_client;
+    let env = setup.env;
+
+    let milestone = Milestone {
+        id: 1,
+        amount: 400,
+        status: MilestoneStatus::Pending,
+        description: String::from_str(&env, "High Value Milestone"),
+    };
+    let milestones = vec![&env, milestone];
+
+    escrow.initialize(&setup.client, &setup.freelancer, &setup.arbiter, &setup.token_address, &milestones);
+    escrow.fund();
+    escrow.submit_milestone(&1);
+    escrow.approve(&1);
+    escrow.freelancer_confirm(&1);
+
+    // Verify both approvals are set
+    assert_eq!(escrow.has_client_approval(&1), true);
+    assert_eq!(escrow.has_freelancer_approval(&1), true);
+
+    // Client disputes the milestone
+    escrow.dispute(&1, &setup.client);
+    assert_eq!(escrow.get_milestones().get(0).unwrap().status, MilestoneStatus::Disputed);
+
+    // Verify approvals are cleared
+    assert_eq!(escrow.has_client_approval(&1), false);
+    assert_eq!(escrow.has_freelancer_approval(&1), false);
+}

contracts/contracts/escrow/test_snapshots/test/test_dispute_and_resolve_to_client.1.json

@@ -84,6 +84,25 @@
         }
       ]
     ],
+    [
+      [
+        "CAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAFCT4",
+        {
+          "function": {
+            "contract_fn": {
+              "contract_address": "CAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAMDR4",
+              "function_name": "submit_milestone",
+              "args": [
+                {
+                  "u32": 1
+                }
+              ]
+            }
+          },
+          "sub_invocations": []
+        }
+      ]
+    ],
     [
       [
         "CAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAFCT4",
@@ -204,6 +223,26 @@
         },
         "live_until": 6311999
       },
+      {
+        "entry": {
+          "last_modified_ledger_seq": 0,
+          "data": {
+            "contract_data": {
+              "ext": "v0",
+              "contract": "CAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAFCT4",
+              "key": {
+                "ledger_key_nonce": {
+                  "nonce": "2032731177588607455"
+                }
+              },
+              "durability": "temporary",
+              "val": "void"
+            }
+          },
+          "ext": "v0"
+        },
+        "live_until": 6311999
+      },
       {
         "entry": {
           "last_modified_ledger_seq": 0,
@@ -233,7 +272,7 @@
               "contract": "CAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAHK3M",
               "key": {
                 "ledger_key_nonce": {
-                  "nonce": "2032731177588607455"
+                  "nonce": "4270020994084947596"
                 }
               },
               "durability": "temporary",