Add payer-wallet override flow with ownership proof in store

docs/roadmap-status.md

@@ -44,6 +44,7 @@ Implemented now:
 17. Download endpoints now validate wallet membership status before authorizing channel messaging.
 18. Governance install API contract, examples, backend handoff checklist, and conformance vectors.
 19. Repo boundary blueprint and free launcher specification aligned with first paid governance model.
+20. Store UI now supports distinct payer wallet overrides with ownership-proof signing before quote requests.
 
 Remaining in this repo:
 

public/store/index.html

@@ -111,6 +111,16 @@
     font-size: 11px;
     color: #3d434a;
   }
+  input {
+    border: 1px solid #c2c8d0;
+    background: #ffffff;
+    padding: 6px 8px;
+    font-family: 'IBM Plex Mono', 'Courier New', monospace;
+    font-size: 11px;
+    color: #3d434a;
+    width: 100%;
+    margin-top: 6px;
+  }
   .status-log {
     margin-top: 12px;
     border-top: 1px solid #d0d5db;
@@ -144,10 +154,14 @@
       <p class="line">Wallet: <span class="mono" id="wallet-label">not connected</span></p>
       <p class="line">Membership status: <span class="mono" id="membership-label">unknown</span></p>
       <p class="line">Gate decision: <span class="mono" id="gate-label">blocked</span></p>
+      <p class="line">Payer wallet override (optional):</p>
+      <input id="payer-wallet-input" type="text" placeholder="0x... (leave blank to use ownership wallet)">
+      <p class="line">Ownership proof: <span class="mono" id="proof-label">not required</span></p>
       <span class="state block" id="gate-pill">membership required</span>
       <div class="actions">
         <button id="connect-btn" type="button">connect wallet</button>
         <button id="refresh-btn" type="button">refresh state</button>
+        <button id="sign-proof-btn" type="button">sign ownership proof</button>
         <label class="line" for="mock-select">mock mode:</label>
         <select id="mock-select" aria-label="Mock state override">
           <option value="">live</option>
@@ -168,7 +182,7 @@
       <p class="line" id="offer-summary">Catalog data pending.</p>
       <p class="line" id="offer-price">Price: --</p>
       <p class="line" id="offer-policy">Policy: --</p>
-      <p class="line">Action chain: membership check -> quote -> wallet confirm -> entitlement receipt</p>
+      <p class="line">Action chain: membership check -> ownership proof (if needed) -> quote -> wallet confirm -> entitlement receipt</p>
       <div class="actions">
         <button id="checkout-btn" type="button" disabled>request checkout quote</button>
       </div>
@@ -193,6 +207,7 @@
 
   const state = {
     wallet: null,
+    ownershipProof: null,
     membership: 'unknown',
     gate: false,
     source: 'live',
@@ -208,8 +223,11 @@
   const checkoutLog = document.getElementById('checkout-log');
   const connectBtn = document.getElementById('connect-btn');
   const refreshBtn = document.getElementById('refresh-btn');
+  const signProofBtn = document.getElementById('sign-proof-btn');
   const checkoutBtn = document.getElementById('checkout-btn');
   const mockSelect = document.getElementById('mock-select');
+  const payerWalletInput = document.getElementById('payer-wallet-input');
+  const proofLabel = document.getElementById('proof-label');
   const offerSelect = document.getElementById('offer-select');
   const offerTitle = document.getElementById('offer-title');
   const offerSummary = document.getElementById('offer-summary');
@@ -221,6 +239,33 @@
     return wallet.slice(0, 6) + '...' + wallet.slice(-4);
   }
 
+  function normalizeWallet(value) {
+    return String(value || '').trim();
+  }
+
+  function isValidWallet(wallet) {
+    return /^0x[a-fA-F0-9]{40}$/.test(wallet);
+  }
+
+  function getPayerWallet() {
+    const override = normalizeWallet(payerWalletInput.value);
+    return override || state.wallet;
+  }
+
+  function updateProofLabel() {
+    const payer = getPayerWallet();
+    if (!state.wallet || !payer || payer.toLowerCase() === state.wallet.toLowerCase()) {
+      proofLabel.textContent = 'not required';
+      return;
+    }
+    if (state.ownershipProof && state.ownershipProof.payer_wallet &&
+      state.ownershipProof.payer_wallet.toLowerCase() === payer.toLowerCase()) {
+      proofLabel.textContent = 'signed';
+      return;
+    }
+    proofLabel.textContent = 'required';
+  }
+
   function setLog(message) {
     statusLog.textContent = message;
   }
@@ -294,6 +339,7 @@
     }
 
     checkoutBtn.disabled = !state.gate || !state.selectedOfferId;
+    updateProofLabel();
   }
 
   function getMockFromQuery() {
@@ -404,6 +450,7 @@
         throw new Error('Wallet connection not approved.');
       }
       state.wallet = accounts[0];
+      state.ownershipProof = null;
       setLog('Wallet connected: ' + abbreviateWallet(state.wallet) + '.');
       await refreshMembershipState();
     } catch (err) {
@@ -411,6 +458,62 @@
     }
   }
 
+  async function signOwnershipProof() {
+    if (!state.wallet) {
+      setLog('Connect ownership wallet first.');
+      return;
+    }
+    if (!window.ethereum) {
+      setLog('No wallet provider detected for signing.');
+      return;
+    }
+
+    const payer = getPayerWallet();
+    if (!payer) {
+      setLog('Payer wallet is empty.');
+      return;
+    }
+    if (!isValidWallet(payer)) {
+      setLog('Payer wallet format is invalid.');
+      return;
+    }
+
+    if (payer.toLowerCase() === state.wallet.toLowerCase()) {
+      state.ownershipProof = null;
+      updateProofLabel();
+      setLog('Ownership proof is not required when payer equals ownership wallet.');
+      return;
+    }
+
+    try {
+      const selectedOffer = state.selectedOfferId || 'none';
+      const issuedAt = new Date().toISOString();
+      const message = [
+        'EDUT OWNERSHIP PROOF',
+        'Ownership wallet: ' + state.wallet,
+        'Payer wallet: ' + payer,
+        'Offer: ' + selectedOffer,
+        'Issued at: ' + issuedAt,
+      ].join('\\n');
+
+      const signature = await window.ethereum.request({
+        method: 'personal_sign',
+        params: [message, state.wallet],
+      });
+
+      state.ownershipProof = {
+        payer_wallet: payer,
+        signature: signature,
+        message: message,
+        issued_at: issuedAt,
+      };
+      updateProofLabel();
+      setLog('Ownership proof signed for payer wallet override.');
+    } catch (err) {
+      setLog('Ownership proof signing failed: ' + err.message + '.');
+    }
+  }
+
   async function requestCheckoutQuote() {
     if (!state.gate) {
       setCheckoutLog('Checkout blocked: membership is not active.');
@@ -422,26 +525,49 @@
       return;
     }
 
+    const payerWallet = getPayerWallet();
+    if (!payerWallet || !isValidWallet(payerWallet)) {
+      setCheckoutLog('Checkout blocked: payer wallet is invalid.');
+      return;
+    }
+
+    const usingDistinctPayer = payerWallet.toLowerCase() !== state.wallet.toLowerCase();
+    if (usingDistinctPayer) {
+      if (!state.ownershipProof ||
+          !state.ownershipProof.signature ||
+          !state.ownershipProof.payer_wallet ||
+          state.ownershipProof.payer_wallet.toLowerCase() !== payerWallet.toLowerCase()) {
+        setCheckoutLog('Checkout blocked: sign ownership proof for the payer wallet override.');
+        return;
+      }
+    }
+
     setCheckoutLog('Requesting quote...');
 
     try {
+      const payload = {
+        wallet: state.wallet,
+        offer_id: state.selectedOfferId,
+      };
+      if (usingDistinctPayer) {
+        payload.payer_wallet = payerWallet;
+        payload.ownership_proof = state.ownershipProof.signature;
+      }
+
       const response = await fetch('/marketplace/checkout/quote', {
         method: 'POST',
         headers: { 'Content-Type': 'application/json' },
-        body: JSON.stringify({
+        body: JSON.stringify(payload),
-          wallet: state.wallet,
-          offer_id: state.selectedOfferId,
-        }),
       });
 
       if (!response.ok) {
         throw new Error('HTTP ' + response.status);
       }
 
-      const payload = await response.json();
+      const quotePayload = await response.json();
-      const quoteId = payload.quote_id || 'unknown';
+      const quoteId = quotePayload.quote_id || 'unknown';
-      const amount = payload.amount || payload.amount_atomic || 'unknown';
+      const amount = quotePayload.amount || quotePayload.amount_atomic || 'unknown';
-      const currency = payload.currency || 'unknown';
+      const currency = quotePayload.currency || 'unknown';
       setCheckoutLog('Quote ready for ' + state.selectedOfferId + ': ' + quoteId + ' (' + amount + ' ' + currency + ').');
     } catch (err) {
       setCheckoutLog('Quote request failed: ' + err.message + '. API wiring pending.');
@@ -450,10 +576,16 @@
 
   connectBtn.addEventListener('click', connectWallet);
   refreshBtn.addEventListener('click', refreshMembershipState);
+  signProofBtn.addEventListener('click', signOwnershipProof);
   checkoutBtn.addEventListener('click', requestCheckoutQuote);
   mockSelect.addEventListener('change', refreshMembershipState);
+  payerWalletInput.addEventListener('input', function () {
+    state.ownershipProof = null;
+    updateProofLabel();
+  });
   offerSelect.addEventListener('change', function () {
     state.selectedOfferId = offerSelect.value;
+    state.ownershipProof = null;
     renderSelectedOffer();
     applyGateState();
   });