fix messaging, small issues and safer types

15 files changed, 310 insertions, 360 deletions

diff --git a/src/crypto/cryptoApi.ts b/src/crypto/cryptoApi.ts
index c3c1f508a..139f8ae88 100644
--- a/src/crypto/cryptoApi.ts
+++ b/src/crypto/cryptoApi.ts
@@ -27,7 +27,7 @@ import {
   AmountJson,
   CoinRecord,
   DenominationRecord,
-  OfferRecord,
+  ProposalRecord,
   PayCoinInfo,
   PaybackRequest,
   PreCoinRecord,
@@ -277,9 +277,9 @@ export class CryptoApi {
     return this.doRpc<PayCoinInfo>("isValidPaymentSignature", 1, sig, contractHash, merchantPub);
   }
 
-  signDeposit(offer: OfferRecord,
+  signDeposit(proposal: ProposalRecord,
               cds: CoinWithDenom[]): Promise<PayCoinInfo> {
-    return this.doRpc<PayCoinInfo>("signDeposit", 3, offer, cds);
+    return this.doRpc<PayCoinInfo>("signDeposit", 3, proposal, cds);
   }
 
   createEddsaKeypair(): Promise<{priv: string, pub: string}> {
diff --git a/src/crypto/cryptoWorker.ts b/src/crypto/cryptoWorker.ts
index 85a0425b3..507a080ac 100644
--- a/src/crypto/cryptoWorker.ts
+++ b/src/crypto/cryptoWorker.ts
@@ -29,7 +29,7 @@ import {
   CoinRecord,
   CoinStatus,
   DenominationRecord,
-  OfferRecord,
+  ProposalRecord,
   PayCoinInfo,
   PaybackRequest,
   PreCoinRecord,
@@ -227,7 +227,7 @@ namespace RpcFunctions {
    * Generate updated coins (to store in the database)
    * and deposit permissions for each given coin.
    */
-  export function signDeposit(offer: OfferRecord,
+  export function signDeposit(proposal: ProposalRecord,
                               cds: CoinWithDenom[]): PayCoinInfo {
     const ret: PayCoinInfo = [];
 
@@ -235,8 +235,8 @@ namespace RpcFunctions {
     const feeList: AmountJson[] = cds.map((x) => x.denom.feeDeposit);
     let fees = Amounts.add(Amounts.getZero(feeList[0].currency), ...feeList).amount;
     // okay if saturates
-    fees = Amounts.sub(fees, offer.contract.max_fee).amount;
-    const total = Amounts.add(fees, offer.contract.amount).amount;
+    fees = Amounts.sub(fees, proposal.contractTerms.max_fee).amount;
+    const total = Amounts.add(fees, proposal.contractTerms.amount).amount;
 
     const amountSpent = native.Amount.getZero(cds[0].coin.currentAmount.currency);
     const amountRemaining = new native.Amount(total);
@@ -273,11 +273,11 @@ namespace RpcFunctions {
         amount_with_fee: coinSpend.toNbo(),
         coin_pub: native.EddsaPublicKey.fromCrock(cd.coin.coinPub),
         deposit_fee: new native.Amount(cd.denom.feeDeposit).toNbo(),
-        h_contract: native.HashCode.fromCrock(offer.H_contract),
-        h_wire: native.HashCode.fromCrock(offer.contract.H_wire),
-        merchant: native.EddsaPublicKey.fromCrock(offer.contract.merchant_pub),
-        refund_deadline: native.AbsoluteTimeNbo.fromTalerString(offer.contract.refund_deadline),
-        timestamp: native.AbsoluteTimeNbo.fromTalerString(offer.contract.timestamp),
+        h_contract: native.HashCode.fromCrock(proposal.contractTermsHash),
+        h_wire: native.HashCode.fromCrock(proposal.contractTerms.H_wire),
+        merchant: native.EddsaPublicKey.fromCrock(proposal.contractTerms.merchant_pub),
+        refund_deadline: native.AbsoluteTimeNbo.fromTalerString(proposal.contractTerms.refund_deadline),
+        timestamp: native.AbsoluteTimeNbo.fromTalerString(proposal.contractTerms.timestamp),
       });
 
       const coinSig = native.eddsaSign(d.toPurpose(),
diff --git a/src/i18n/de.po b/src/i18n/de.po
index 1578830b5..d90a9340e 100644
--- a/src/i18n/de.po
+++ b/src/i18n/de.po
@@ -42,13 +42,13 @@ msgstr ""
 msgid "Exchanges in the wallet:"
 msgstr ""
 
-#: src/webex/pages/confirm-contract.tsx:146
+#: src/webex/pages/confirm-contract.tsx:141
 #, c-format
 msgid "You have insufficient funds of the requested currency in your wallet."
 msgstr ""
 
 #. tslint:disable-next-line:max-line-length
-#: src/webex/pages/confirm-contract.tsx:148
+#: src/webex/pages/confirm-contract.tsx:143
 #, c-format
 msgid ""
 "You do not have any funds from an exchange that is accepted by this "
@@ -193,90 +193,90 @@ msgstr ""
 msgid "Fatal error: \"%1$s\"."
 msgstr ""
 
-#: src/webex/pages/popup.tsx:163
+#: src/webex/pages/popup.tsx:161
 #, c-format
 msgid "Balance"
 msgstr "Saldo"
 
-#: src/webex/pages/popup.tsx:166
+#: src/webex/pages/popup.tsx:164
 #, c-format
 msgid "History"
 msgstr "Verlauf"
 
-#: src/webex/pages/popup.tsx:169
+#: src/webex/pages/popup.tsx:167
 #, c-format
 msgid "Debug"
 msgstr "Debug"
 
-#: src/webex/pages/popup.tsx:245
+#: src/webex/pages/popup.tsx:243
 #, c-format
 msgid "help"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:250
+#: src/webex/pages/popup.tsx:248
 #, fuzzy, c-format
 msgid ""
 "You have no balance to show. Need some\n"
 " %1$s getting started?\n"
 msgstr "Sie haben kein Digitalgeld. Wollen Sie %1$s? abheben?"
 
-#: src/webex/pages/popup.tsx:267
+#: src/webex/pages/popup.tsx:265
 #, c-format
 msgid "%1$s incoming\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:280
+#: src/webex/pages/popup.tsx:278
 #, c-format
 msgid "%1$s being spent\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:306
+#: src/webex/pages/popup.tsx:304
 #, c-format
 msgid "Error: could not retrieve balance information."
 msgstr ""
 
-#: src/webex/pages/popup.tsx:345
+#: src/webex/pages/popup.tsx:343
 #, fuzzy, c-format
 msgid ""
 "Bank requested reserve (%1$s) for\n"
 " %2$s.\n"
 msgstr "Bank bestätig anlegen der Reserve (%1$s) bei %2$s"
 
-#: src/webex/pages/popup.tsx:356
+#: src/webex/pages/popup.tsx:354
 #, fuzzy, c-format
 msgid ""
 "Started to withdraw\n"
 " %1$s from%2$s(%3$s).\n"
 msgstr "Reserve (%1$s) mit %2$s bei %3$s erzeugt"
 
-#: src/webex/pages/popup.tsx:366
+#: src/webex/pages/popup.tsx:364
 #, c-format
 msgid "Merchant%1$soffered contract%2$s;\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:376
+#: src/webex/pages/popup.tsx:374
 #, fuzzy, c-format
 msgid "Withdrew%1$sfrom%2$s(%3$s).\n"
 msgstr "Reserve (%1$s) mit %2$s bei %3$s erzeugt"
 
-#: src/webex/pages/popup.tsx:386
+#: src/webex/pages/popup.tsx:384
 #, fuzzy, c-format
 msgid ""
 "Paid%1$sto merchant%2$s.\n"
 " (%3$s)\n"
 msgstr "Reserve (%1$s) mit %2$s bei %3$s erzeugt"
 
-#: src/webex/pages/popup.tsx:395
+#: src/webex/pages/popup.tsx:393
 #, c-format
 msgid "Unknown event (%1$s)"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:438
+#: src/webex/pages/popup.tsx:436
 #, c-format
 msgid "Error: could not retrieve event history"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:472
+#: src/webex/pages/popup.tsx:470
 #, c-format
 msgid "Your wallet has no events recorded."
 msgstr "Ihre Geldbörse verzeichnet keine Vorkommnisse."
diff --git a/src/i18n/en-US.po b/src/i18n/en-US.po
index f7faad5fd..f45591db6 100644
--- a/src/i18n/en-US.po
+++ b/src/i18n/en-US.po
@@ -42,13 +42,13 @@ msgstr ""
 msgid "Exchanges in the wallet:"
 msgstr ""
 
-#: src/webex/pages/confirm-contract.tsx:146
+#: src/webex/pages/confirm-contract.tsx:141
 #, c-format
 msgid "You have insufficient funds of the requested currency in your wallet."
 msgstr ""
 
 #. tslint:disable-next-line:max-line-length
-#: src/webex/pages/confirm-contract.tsx:148
+#: src/webex/pages/confirm-contract.tsx:143
 #, c-format
 msgid ""
 "You do not have any funds from an exchange that is accepted by this "
@@ -193,90 +193,90 @@ msgstr ""
 msgid "Fatal error: \"%1$s\"."
 msgstr ""
 
-#: src/webex/pages/popup.tsx:163
+#: src/webex/pages/popup.tsx:161
 #, c-format
 msgid "Balance"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:166
+#: src/webex/pages/popup.tsx:164
 #, c-format
 msgid "History"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:169
+#: src/webex/pages/popup.tsx:167
 #, c-format
 msgid "Debug"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:245
+#: src/webex/pages/popup.tsx:243
 #, c-format
 msgid "help"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:250
+#: src/webex/pages/popup.tsx:248
 #, c-format
 msgid ""
 "You have no balance to show. Need some\n"
 " %1$s getting started?\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:267
+#: src/webex/pages/popup.tsx:265
 #, c-format
 msgid "%1$s incoming\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:280
+#: src/webex/pages/popup.tsx:278
 #, c-format
 msgid "%1$s being spent\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:306
+#: src/webex/pages/popup.tsx:304
 #, c-format
 msgid "Error: could not retrieve balance information."
 msgstr ""
 
-#: src/webex/pages/popup.tsx:345
+#: src/webex/pages/popup.tsx:343
 #, c-format
 msgid ""
 "Bank requested reserve (%1$s) for\n"
 " %2$s.\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:356
+#: src/webex/pages/popup.tsx:354
 #, c-format
 msgid ""
 "Started to withdraw\n"
 " %1$s from%2$s(%3$s).\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:366
+#: src/webex/pages/popup.tsx:364
 #, c-format
 msgid "Merchant%1$soffered contract%2$s;\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:376
+#: src/webex/pages/popup.tsx:374
 #, c-format
 msgid "Withdrew%1$sfrom%2$s(%3$s).\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:386
+#: src/webex/pages/popup.tsx:384
 #, c-format
 msgid ""
 "Paid%1$sto merchant%2$s.\n"
 " (%3$s)\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:395
+#: src/webex/pages/popup.tsx:393
 #, c-format
 msgid "Unknown event (%1$s)"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:438
+#: src/webex/pages/popup.tsx:436
 #, c-format
 msgid "Error: could not retrieve event history"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:472
+#: src/webex/pages/popup.tsx:470
 #, c-format
 msgid "Your wallet has no events recorded."
 msgstr ""
diff --git a/src/i18n/fr.po b/src/i18n/fr.po
index 2011e1bb8..17f596b2f 100644
--- a/src/i18n/fr.po
+++ b/src/i18n/fr.po
@@ -42,13 +42,13 @@ msgstr ""
 msgid "Exchanges in the wallet:"
 msgstr ""
 
-#: src/webex/pages/confirm-contract.tsx:146
+#: src/webex/pages/confirm-contract.tsx:141
 #, c-format
 msgid "You have insufficient funds of the requested currency in your wallet."
 msgstr ""
 
 #. tslint:disable-next-line:max-line-length
-#: src/webex/pages/confirm-contract.tsx:148
+#: src/webex/pages/confirm-contract.tsx:143
 #, c-format
 msgid ""
 "You do not have any funds from an exchange that is accepted by this "
@@ -193,90 +193,90 @@ msgstr ""
 msgid "Fatal error: \"%1$s\"."
 msgstr ""
 
-#: src/webex/pages/popup.tsx:163
+#: src/webex/pages/popup.tsx:161
 #, c-format
 msgid "Balance"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:166
+#: src/webex/pages/popup.tsx:164
 #, c-format
 msgid "History"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:169
+#: src/webex/pages/popup.tsx:167
 #, c-format
 msgid "Debug"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:245
+#: src/webex/pages/popup.tsx:243
 #, c-format
 msgid "help"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:250
+#: src/webex/pages/popup.tsx:248
 #, c-format
 msgid ""
 "You have no balance to show. Need some\n"
 " %1$s getting started?\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:267
+#: src/webex/pages/popup.tsx:265
 #, c-format
 msgid "%1$s incoming\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:280
+#: src/webex/pages/popup.tsx:278
 #, c-format
 msgid "%1$s being spent\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:306
+#: src/webex/pages/popup.tsx:304
 #, c-format
 msgid "Error: could not retrieve balance information."
 msgstr ""
 
-#: src/webex/pages/popup.tsx:345
+#: src/webex/pages/popup.tsx:343
 #, c-format
 msgid ""
 "Bank requested reserve (%1$s) for\n"
 " %2$s.\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:356
+#: src/webex/pages/popup.tsx:354
 #, c-format
 msgid ""
 "Started to withdraw\n"
 " %1$s from%2$s(%3$s).\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:366
+#: src/webex/pages/popup.tsx:364
 #, c-format
 msgid "Merchant%1$soffered contract%2$s;\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:376
+#: src/webex/pages/popup.tsx:374
 #, c-format
 msgid "Withdrew%1$sfrom%2$s(%3$s).\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:386
+#: src/webex/pages/popup.tsx:384
 #, c-format
 msgid ""
 "Paid%1$sto merchant%2$s.\n"
 " (%3$s)\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:395
+#: src/webex/pages/popup.tsx:393
 #, c-format
 msgid "Unknown event (%1$s)"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:438
+#: src/webex/pages/popup.tsx:436
 #, c-format
 msgid "Error: could not retrieve event history"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:472
+#: src/webex/pages/popup.tsx:470
 #, c-format
 msgid "Your wallet has no events recorded."
 msgstr ""
diff --git a/src/i18n/it.po b/src/i18n/it.po
index 2011e1bb8..17f596b2f 100644
--- a/src/i18n/it.po
+++ b/src/i18n/it.po
@@ -42,13 +42,13 @@ msgstr ""
 msgid "Exchanges in the wallet:"
 msgstr ""
 
-#: src/webex/pages/confirm-contract.tsx:146
+#: src/webex/pages/confirm-contract.tsx:141
 #, c-format
 msgid "You have insufficient funds of the requested currency in your wallet."
 msgstr ""
 
 #. tslint:disable-next-line:max-line-length
-#: src/webex/pages/confirm-contract.tsx:148
+#: src/webex/pages/confirm-contract.tsx:143
 #, c-format
 msgid ""
 "You do not have any funds from an exchange that is accepted by this "
@@ -193,90 +193,90 @@ msgstr ""
 msgid "Fatal error: \"%1$s\"."
 msgstr ""
 
-#: src/webex/pages/popup.tsx:163
+#: src/webex/pages/popup.tsx:161
 #, c-format
 msgid "Balance"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:166
+#: src/webex/pages/popup.tsx:164
 #, c-format
 msgid "History"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:169
+#: src/webex/pages/popup.tsx:167
 #, c-format
 msgid "Debug"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:245
+#: src/webex/pages/popup.tsx:243
 #, c-format
 msgid "help"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:250
+#: src/webex/pages/popup.tsx:248
 #, c-format
 msgid ""
 "You have no balance to show. Need some\n"
 " %1$s getting started?\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:267
+#: src/webex/pages/popup.tsx:265
 #, c-format
 msgid "%1$s incoming\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:280
+#: src/webex/pages/popup.tsx:278
 #, c-format
 msgid "%1$s being spent\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:306
+#: src/webex/pages/popup.tsx:304
 #, c-format
 msgid "Error: could not retrieve balance information."
 msgstr ""
 
-#: src/webex/pages/popup.tsx:345
+#: src/webex/pages/popup.tsx:343
 #, c-format
 msgid ""
 "Bank requested reserve (%1$s) for\n"
 " %2$s.\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:356
+#: src/webex/pages/popup.tsx:354
 #, c-format
 msgid ""
 "Started to withdraw\n"
 " %1$s from%2$s(%3$s).\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:366
+#: src/webex/pages/popup.tsx:364
 #, c-format
 msgid "Merchant%1$soffered contract%2$s;\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:376
+#: src/webex/pages/popup.tsx:374
 #, c-format
 msgid "Withdrew%1$sfrom%2$s(%3$s).\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:386
+#: src/webex/pages/popup.tsx:384
 #, c-format
 msgid ""
 "Paid%1$sto merchant%2$s.\n"
 " (%3$s)\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:395
+#: src/webex/pages/popup.tsx:393
 #, c-format
 msgid "Unknown event (%1$s)"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:438
+#: src/webex/pages/popup.tsx:436
 #, c-format
 msgid "Error: could not retrieve event history"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:472
+#: src/webex/pages/popup.tsx:470
 #, c-format
 msgid "Your wallet has no events recorded."
 msgstr ""
diff --git a/src/i18n/taler-wallet-webex.pot b/src/i18n/taler-wallet-webex.pot
index 2011e1bb8..17f596b2f 100644
--- a/src/i18n/taler-wallet-webex.pot
+++ b/src/i18n/taler-wallet-webex.pot
@@ -42,13 +42,13 @@ msgstr ""
 msgid "Exchanges in the wallet:"
 msgstr ""
 
-#: src/webex/pages/confirm-contract.tsx:146
+#: src/webex/pages/confirm-contract.tsx:141
 #, c-format
 msgid "You have insufficient funds of the requested currency in your wallet."
 msgstr ""
 
 #. tslint:disable-next-line:max-line-length
-#: src/webex/pages/confirm-contract.tsx:148
+#: src/webex/pages/confirm-contract.tsx:143
 #, c-format
 msgid ""
 "You do not have any funds from an exchange that is accepted by this "
@@ -193,90 +193,90 @@ msgstr ""
 msgid "Fatal error: \"%1$s\"."
 msgstr ""
 
-#: src/webex/pages/popup.tsx:163
+#: src/webex/pages/popup.tsx:161
 #, c-format
 msgid "Balance"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:166
+#: src/webex/pages/popup.tsx:164
 #, c-format
 msgid "History"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:169
+#: src/webex/pages/popup.tsx:167
 #, c-format
 msgid "Debug"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:245
+#: src/webex/pages/popup.tsx:243
 #, c-format
 msgid "help"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:250
+#: src/webex/pages/popup.tsx:248
 #, c-format
 msgid ""
 "You have no balance to show. Need some\n"
 " %1$s getting started?\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:267
+#: src/webex/pages/popup.tsx:265
 #, c-format
 msgid "%1$s incoming\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:280
+#: src/webex/pages/popup.tsx:278
 #, c-format
 msgid "%1$s being spent\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:306
+#: src/webex/pages/popup.tsx:304
 #, c-format
 msgid "Error: could not retrieve balance information."
 msgstr ""
 
-#: src/webex/pages/popup.tsx:345
+#: src/webex/pages/popup.tsx:343
 #, c-format
 msgid ""
 "Bank requested reserve (%1$s) for\n"
 " %2$s.\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:356
+#: src/webex/pages/popup.tsx:354
 #, c-format
 msgid ""
 "Started to withdraw\n"
 " %1$s from%2$s(%3$s).\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:366
+#: src/webex/pages/popup.tsx:364
 #, c-format
 msgid "Merchant%1$soffered contract%2$s;\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:376
+#: src/webex/pages/popup.tsx:374
 #, c-format
 msgid "Withdrew%1$sfrom%2$s(%3$s).\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:386
+#: src/webex/pages/popup.tsx:384
 #, c-format
 msgid ""
 "Paid%1$sto merchant%2$s.\n"
 " (%3$s)\n"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:395
+#: src/webex/pages/popup.tsx:393
 #, c-format
 msgid "Unknown event (%1$s)"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:438
+#: src/webex/pages/popup.tsx:436
 #, c-format
 msgid "Error: could not retrieve event history"
 msgstr ""
 
-#: src/webex/pages/popup.tsx:472
+#: src/webex/pages/popup.tsx:470
 #, c-format
 msgid "Your wallet has no events recorded."
 msgstr ""
diff --git a/src/types.ts b/src/types.ts
index 4dee93a10..82777f96b 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -1047,33 +1047,27 @@ export class Contract {
 
 
 /**
- * Offer record, stored in the wallet's database.
+ * Proposal record, stored in the wallet's database.
  */
 @Checkable.Class()
-export class OfferRecord {
+export class ProposalRecord {
   /**
    * The contract that was offered by the merchant.
    */
   @Checkable.Value(Contract)
-  contract: Contract;
+  contractTerms: Contract;
 
   /**
    * Signature by the merchant over the contract details.
    */
   @Checkable.String
-  merchant_sig: string;
+  merchantSig: string;
 
   /**
    * Hash of the contract terms.
    */
   @Checkable.String
-  H_contract: string;
-
-  /**
-   * Time when the offer was made.
-   */
-  @Checkable.Number
-  offer_time: number;
+  contractTermsHash: string;
 
   /**
    * Serial ID when the offer is stored in the wallet DB.
@@ -1085,7 +1079,7 @@ export class OfferRecord {
    * Verify that a value matches the schema of this class and convert it into a
    * member.
    */
-  static checked: (obj: any) => OfferRecord;
+  static checked: (obj: any) => ProposalRecord;
 }
 
 
diff --git a/src/wallet.ts b/src/wallet.ts
index 51c99e805..4aa2329d8 100644
--- a/src/wallet.ts
+++ b/src/wallet.ts
@@ -63,7 +63,7 @@ import {
   HistoryLevel,
   HistoryRecord,
   Notifier,
-  OfferRecord,
+  ProposalRecord,
   PayCoinInfo,
   PaybackConfirmation,
   PreCoinRecord,
@@ -507,9 +507,9 @@ export namespace Stores {
     timestampIndex = new Index<number, HistoryRecord>(this, "timestamp", "timestamp");
   }
 
-  class OffersStore extends Store<OfferRecord> {
+  class ProposalsStore extends Store<ProposalRecord> {
     constructor() {
-      super("offers", {
+      super("proposals", {
         autoIncrement: true,
         keyPath: "id",
       });
@@ -555,19 +555,19 @@ export namespace Stores {
     }
   }
 
-  export const exchanges = new ExchangeStore();
-  export const exchangeWireFees = new ExchangeWireFeesStore();
-  export const nonces = new NonceStore();
-  export const transactions = new TransactionsStore();
-  export const reserves = new Store<ReserveRecord>("reserves", {keyPath: "reserve_pub"});
   export const coins = new CoinsStore();
-  export const refresh = new Store<RefreshSessionRecord>("refresh", {keyPath: "meltCoinPub"});
+  export const config = new ConfigStore();
+  export const currencies = new CurrenciesStore();
+  export const denominations = new DenominationsStore();
+  export const exchangeWireFees = new ExchangeWireFeesStore();
+  export const exchanges = new ExchangeStore();
   export const history = new HistoryStore();
-  export const offers = new OffersStore();
+  export const nonces = new NonceStore();
   export const precoins = new Store<PreCoinRecord>("precoins", {keyPath: "coinPub"});
-  export const denominations = new DenominationsStore();
-  export const currencies = new CurrenciesStore();
-  export const config = new ConfigStore();
+  export const proposals = new ProposalsStore();
+  export const refresh = new Store<RefreshSessionRecord>("refresh", {keyPath: "meltCoinPub"});
+  export const reserves = new Store<ReserveRecord>("reserves", {keyPath: "reserve_pub"});
+  export const transactions = new TransactionsStore();
 }
 
 /* tslint:enable:completed-docs */
@@ -834,32 +834,32 @@ export class Wallet {
    * Record all information that is necessary to
    * pay for a contract in the wallet's database.
    */
-  private async recordConfirmPay(offer: OfferRecord,
+  private async recordConfirmPay(proposal: ProposalRecord,
                                  payCoinInfo: PayCoinInfo,
                                  chosenExchange: string): Promise<void> {
     const payReq: PayReq = {
       coins: payCoinInfo.map((x) => x.sig),
       exchange: chosenExchange,
-      merchant_pub: offer.contract.merchant_pub,
-      order_id: offer.contract.order_id,
+      merchant_pub: proposal.contractTerms.merchant_pub,
+      order_id: proposal.contractTerms.order_id,
     };
     const t: TransactionRecord = {
-      contract: offer.contract,
-      contractHash: offer.H_contract,
+      contract: proposal.contractTerms,
+      contractHash: proposal.contractTermsHash,
       finished: false,
-      merchantSig: offer.merchant_sig,
+      merchantSig: proposal.merchantSig,
       payReq,
     };
 
     const historyEntry: HistoryRecord = {
       detail: {
-        amount: offer.contract.amount,
-        contractHash: offer.H_contract,
-        fulfillmentUrl: offer.contract.fulfillment_url,
-        merchantName: offer.contract.merchant.name,
+        amount: proposal.contractTerms.amount,
+        contractHash: proposal.contractTermsHash,
+        fulfillmentUrl: proposal.contractTerms.fulfillment_url,
+        merchantName: proposal.contractTerms.merchant.name,
       },
       level: HistoryLevel.User,
-      subjectId: `contract-${offer.H_contract}`,
+      subjectId: `contract-${proposal.contractTermsHash}`,
       timestamp: (new Date()).getTime(),
       type: "pay",
     };
@@ -880,11 +880,13 @@ export class Wallet {
   }
 
 
-  async saveOffer(offer: OfferRecord): Promise<number> {
-    console.log(`saving offer in wallet.ts`);
-    const id = await this.q().putWithResult(Stores.offers, offer);
+  /**
+   * Save a proposal in the database and return an id for it to
+   * retrieve it later.
+   */
+  async saveProposal(proposal: ProposalRecord): Promise<number> {
+    const id = await this.q().putWithResult(Stores.proposals, proposal);
     this.notifier.notify();
-    console.log(`saved offer with id ${id}`);
     if (typeof id !== "number") {
       throw Error("db schema wrong");
     }
@@ -896,10 +898,15 @@ export class Wallet {
    * Add a contract to the wallet and sign coins,
    * but do not send them yet.
    */
-  async confirmPay(offer: OfferRecord): Promise<ConfirmPayResult> {
+  async confirmPay(proposalId: number): Promise<ConfirmPayResult> {
     console.log("executing confirmPay");
+    const proposal = await this.q().get(Stores.proposals, proposalId);
+
+    if (!proposal) {
+      throw Error(`proposal with id ${proposalId} not found`);
+    }
 
-    const transaction = await this.q().get(Stores.transactions, offer.H_contract);
+    const transaction = await this.q().get(Stores.transactions, proposal.contractTermsHash);
 
     if (transaction) {
       // Already payed ...
@@ -907,17 +914,17 @@ export class Wallet {
     }
 
     const res = await this.getCoinsForPayment({
-      allowedAuditors: offer.contract.auditors,
-      allowedExchanges: offer.contract.exchanges,
-      depositFeeLimit: offer.contract.max_fee,
-      paymentAmount: offer.contract.amount,
-      wireFeeAmortization: offer.contract.wire_fee_amortization || 1,
-      wireFeeLimit: offer.contract.max_wire_fee || Amounts.getZero(offer.contract.amount.currency),
-      wireFeeTime: getTalerStampSec(offer.contract.timestamp) || 0,
-      wireMethod: offer.contract.wire_method,
+      allowedAuditors: proposal.contractTerms.auditors,
+      allowedExchanges: proposal.contractTerms.exchanges,
+      depositFeeLimit: proposal.contractTerms.max_fee,
+      paymentAmount: proposal.contractTerms.amount,
+      wireFeeAmortization: proposal.contractTerms.wire_fee_amortization || 1,
+      wireFeeLimit: proposal.contractTerms.max_wire_fee || Amounts.getZero(proposal.contractTerms.amount.currency),
+      wireFeeTime: getTalerStampSec(proposal.contractTerms.timestamp) || 0,
+      wireMethod: proposal.contractTerms.wire_method,
     });
 
-    console.log("max_fee", offer.contract.max_fee);
+    console.log("max_fee", proposal.contractTerms.max_fee);
     console.log("coin selection result", res);
 
     if (!res) {
@@ -926,8 +933,8 @@ export class Wallet {
     }
     const {exchangeUrl, cds} = res;
 
-    const ds = await this.cryptoApi.signDeposit(offer, cds);
-    await this.recordConfirmPay(offer, ds, exchangeUrl);
+    const ds = await this.cryptoApi.signDeposit(proposal, cds);
+    await this.recordConfirmPay(proposal, ds, exchangeUrl);
     return "paid";
   }
 
@@ -936,23 +943,29 @@ export class Wallet {
    * Check if payment for an offer is possible, or if the offer has already
    * been payed for.
    */
-  async checkPay(offer: OfferRecord): Promise<CheckPayResult> {
+  async checkPay(proposalId: number): Promise<CheckPayResult> {
+    const proposal = await this.q().get(Stores.proposals, proposalId);
+
+    if (!proposal) {
+      throw Error(`proposal with id ${proposalId} not found`);
+    }
+
     // First check if we already payed for it.
-    const transaction = await this.q().get(Stores.transactions, offer.H_contract);
+    const transaction = await this.q().get(Stores.transactions, proposal.contractTermsHash);
     if (transaction) {
       return "insufficient-balance";
     }
 
     // If not already payed, check if we could pay for it.
     const res = await this.getCoinsForPayment({
-      allowedAuditors: offer.contract.auditors,
-      allowedExchanges: offer.contract.exchanges,
-      depositFeeLimit: offer.contract.max_fee,
-      paymentAmount: offer.contract.amount,
-      wireFeeAmortization: offer.contract.wire_fee_amortization || 1,
-      wireFeeLimit: offer.contract.max_wire_fee || Amounts.getZero(offer.contract.amount.currency),
-      wireFeeTime: getTalerStampSec(offer.contract.timestamp) || 0,
-      wireMethod: offer.contract.wire_method,
+      allowedAuditors: proposal.contractTerms.auditors,
+      allowedExchanges: proposal.contractTerms.exchanges,
+      depositFeeLimit: proposal.contractTerms.max_fee,
+      paymentAmount: proposal.contractTerms.amount,
+      wireFeeAmortization: proposal.contractTerms.wire_fee_amortization || 1,
+      wireFeeLimit: proposal.contractTerms.max_wire_fee || Amounts.getZero(proposal.contractTerms.amount.currency),
+      wireFeeTime: getTalerStampSec(proposal.contractTerms.timestamp) || 0,
+      wireMethod: proposal.contractTerms.wire_method,
     });
 
     if (!res) {
@@ -2110,9 +2123,9 @@ export class Wallet {
     return denoms;
   }
 
-  async getOffer(offerId: number): Promise<any> {
-    const offer = await this.q() .get(Stores.offers, offerId);
-    return offer;
+  async getProposal(proposalId: number): Promise<ProposalRecord|undefined> {
+    const proposal = await this.q().get(Stores.proposals, proposalId);
+    return proposal;
   }
 
   async getExchanges(): Promise<ExchangeRecord[]> {
diff --git a/src/webex/messages.ts b/src/webex/messages.ts
index 21acfc1d5..27ff9a5b6 100644
--- a/src/webex/messages.ts
+++ b/src/webex/messages.ts
@@ -69,11 +69,11 @@ export interface MessageMap {
     response: string;
   };
   "confirm-pay": {
-    request: { offer: types.OfferRecord; };
+    request: { proposalId: number; };
     response: types.ConfirmPayResult;
   };
   "check-pay": {
-    request: { offer: types.OfferRecord; };
+    request: { proposalId: number; };
     response: types.CheckPayResult;
   };
   "query-payment": {
@@ -96,21 +96,29 @@ export interface MessageMap {
     request: { historyEntry: types.HistoryRecord };
     response: void;
   };
-  "safe-offer": {
-    request: { offer: types.OfferRecord };
+  "save-proposal": {
+    request: { proposal: types.ProposalRecord };
     response: void;
   };
   "reserve-creation-info": {
-    request: { baseUrl: string };
+    request: { baseUrl: string, amount: types.AmountJson };
     response: types.ReserveCreationInfo;
   }
   "get-history": {
     request: { };
     response: types.HistoryRecord[];
   };
-  "get-offer": {
-    request: { offerId: number };
-    response: types.OfferRecord | undefined;
+  "get-proposal": {
+    request: { proposalId: number };
+    response: types.ProposalRecord | undefined;
+  };
+  "get-coins": {
+    request: { exchangeBaseUrl: string };
+    response: any;
+  };
+  "refresh-coin": {
+    request: { coinPub: string };
+    response: any;
   };
   "get-currencies": {
     request: { };
@@ -120,6 +128,10 @@ export interface MessageMap {
     request: { currencyRecord: types.CurrencyRecord };
     response: void;
   };
+  "get-exchanges": {
+    request: { };
+    response: types.ExchangeRecord[];
+  };
   "get-reserves": {
     request: { exchangeBaseUrl: string };
     response: types.ReserveRecord[];
diff --git a/src/webex/notify.ts b/src/webex/notify.ts
index 81bc6808d..2f38658bd 100644
--- a/src/webex/notify.ts
+++ b/src/webex/notify.ts
@@ -280,7 +280,8 @@ async function processProposal(proposal: any) {
   const contractHash = await wxApi.hashContract(proposal.data);
 
   if (contractHash !== proposal.hash) {
-    console.error("merchant-supplied contract hash is wrong");
+    console.error(`merchant-supplied contract hash is wrong (us: ${contractHash}, merchant: ${proposal.hash})`);
+    console.dir(proposal.data);
     return;
   }
 
@@ -301,12 +302,11 @@ async function processProposal(proposal: any) {
     type: "offer-contract",
   };
   await wxApi.putHistory(historyEntry);
-  const offerId = await wxApi.saveOffer(proposal);
+  let proposalId = await wxApi.saveProposal(proposal);
 
-  const uri = new URI(chrome.extension.getURL(
-    "/src/webex/pages/confirm-contract.html"));
+  const uri = new URI(chrome.extension.getURL("/src/webex/pages/confirm-contract.html"));
   const params = {
-    offerId: offerId.toString(),
+    proposalId: proposalId.toString(),
   };
   const target = uri.query(params).href();
   document.location.replace(target);
diff --git a/src/webex/pages/confirm-contract.html b/src/webex/pages/confirm-contract.html
index 6713b2e2c..e5ba68404 100644
--- a/src/webex/pages/confirm-contract.html
+++ b/src/webex/pages/confirm-contract.html
@@ -5,7 +5,7 @@
   <meta charset="UTF-8">
   <title>Taler Wallet: Confirm Reserve Creation</title>
 
-  <link rel="stylesheet" type="text/css" href="/src/style/wallet.css">
+  <link rel="stylesheet" type="text/css" href="../style/wallet.css">
 
   <link rel="icon" href="/img/icon.png">
 
diff --git a/src/webex/pages/confirm-contract.tsx b/src/webex/pages/confirm-contract.tsx
index 9b4c93334..c5513f7c6 100644
--- a/src/webex/pages/confirm-contract.tsx
+++ b/src/webex/pages/confirm-contract.tsx
@@ -27,7 +27,7 @@ import * as i18n from "../../i18n";
 import {
   Contract,
   ExchangeRecord,
-  OfferRecord,
+  ProposalRecord,
 } from "../../types";
 
 import { renderContract } from "../renderHtml";
@@ -98,11 +98,11 @@ class Details extends React.Component<DetailProps, DetailState> {
 }
 
 interface ContractPromptProps {
-  offerId: number;
+  proposalId: number;
 }
 
 interface ContractPromptState {
-  offer: OfferRecord|null;
+  proposal: ProposalRecord|null;
   error: string|null;
   payDisabled: boolean;
   exchanges: null|ExchangeRecord[];
@@ -114,7 +114,7 @@ class ContractPrompt extends React.Component<ContractPromptProps, ContractPrompt
     this.state = {
       error: null,
       exchanges: null,
-      offer: null,
+      proposal: null,
       payDisabled: true,
     };
   }
@@ -128,26 +128,21 @@ class ContractPrompt extends React.Component<ContractPromptProps, ContractPrompt
   }
 
   async update() {
-    const offer = await wxApi.getOffer(this.props.offerId);
-    this.setState({offer} as any);
+    const proposal = await wxApi.getProposal(this.props.proposalId);
+    this.setState({proposal} as any);
     this.checkPayment();
     const exchanges = await wxApi.getExchanges();
     this.setState({exchanges} as any);
   }
 
   async checkPayment() {
-    const offer = this.state.offer;
-    if (!offer) {
-      return;
-    }
-    const payStatus = await wxApi.checkPay(offer);
-
+    const payStatus = await wxApi.checkPay(this.props.proposalId);
     if (payStatus === "insufficient-balance") {
       const msgInsufficient = i18n.str`You have insufficient funds of the requested currency in your wallet.`;
       // tslint:disable-next-line:max-line-length
       const msgNoMatch = i18n.str`You do not have any funds from an exchange that is accepted by this merchant. None of the exchanges accepted by the merchant is known to your wallet.`;
-      if (this.state.exchanges && this.state.offer) {
-        const acceptedExchangePubs = this.state.offer.contract.exchanges.map((e) => e.master_pub);
+      if (this.state.exchanges && this.state.proposal) {
+        const acceptedExchangePubs = this.state.proposal.contractTerms.exchanges.map((e) => e.master_pub);
         const ex = this.state.exchanges.find((e) => acceptedExchangePubs.indexOf(e.masterPublicKey) >= 0);
         if (ex) {
           this.setState({error: msgInsufficient});
@@ -165,28 +160,28 @@ class ContractPrompt extends React.Component<ContractPromptProps, ContractPrompt
   }
 
   async doPayment() {
-    const offer = this.state.offer;
-    if (!offer) {
+    const proposal = this.state.proposal;
+    if (!proposal) {
       return;
     }
-    const payStatus = await wxApi.confirmPay(offer);
+    const payStatus = await wxApi.confirmPay(this.props.proposalId);
     switch (payStatus) {
       case "insufficient-balance":
         this.checkPayment();
         return;
       case "paid":
-        console.log("contract", offer.contract);
-        document.location.href = offer.contract.fulfillment_url;
+        console.log("contract", proposal.contractTerms);
+        document.location.href = proposal.contractTerms.fulfillment_url;
         break;
     }
   }
 
 
   render() {
-    if (!this.state.offer) {
+    if (!this.state.proposal) {
       return <span>...</span>;
     }
-    const c = this.state.offer.contract;
+    const c = this.state.proposal.contractTerms;
     return (
       <div>
         <div>
@@ -210,8 +205,8 @@ class ContractPrompt extends React.Component<ContractPromptProps, ContractPrompt
 document.addEventListener("DOMContentLoaded", () => {
   const url = new URI(document.location.href);
   const query: any = URI.parseQuery(url.query());
-  const offerId = JSON.parse(query.offerId);
+  const proposalId = JSON.parse(query.proposalId);
 
-  ReactDOM.render(<ContractPrompt offerId={offerId}/>, document.getElementById(
+  ReactDOM.render(<ContractPrompt proposalId={proposalId}/>, document.getElementById(
     "contract")!);
 });
diff --git a/src/webex/wxApi.ts b/src/webex/wxApi.ts
index ff601b6f7..4babb2a79 100644
--- a/src/webex/wxApi.ts
+++ b/src/webex/wxApi.ts
@@ -30,15 +30,16 @@ import {
   CurrencyRecord,
   DenominationRecord,
   ExchangeRecord,
-  OfferRecord,
   PreCoinRecord,
   ReserveCreationInfo,
   ReserveRecord,
 } from "../types";
 
+import { MessageType, MessageMap } from "./messages";
 
 
-async function callBackend(type: string, detail?: any): Promise<any> {
+
+async function callBackend<T extends MessageType>(type: T, detail: MessageMap[T]["request"]): Promise<any> {
   return new Promise<any>((resolve, reject) => {
     chrome.runtime.sendMessage({ type, detail }, (resp) => {
       if (resp && resp.error) {
@@ -65,7 +66,7 @@ export function getReserveCreationInfo(baseUrl: string,
  * Get all exchanges the wallet knows about.
  */
 export function getExchanges(): Promise<ExchangeRecord[]> {
-  return callBackend("get-exchanges");
+  return callBackend("get-exchanges", { });
 }
 
 
@@ -73,7 +74,7 @@ export function getExchanges(): Promise<ExchangeRecord[]> {
  * Get all currencies the exchange knows about.
  */
 export function getCurrencies(): Promise<CurrencyRecord[]> {
-  return callBackend("get-currencies");
+  return callBackend("get-currencies", { });
 }
 
 
@@ -114,7 +115,7 @@ export function getReserves(exchangeBaseUrl: string): Promise<ReserveRecord[]> {
  * Get all reserves for which a payback is available.
  */
 export function getPaybackReserves(): Promise<ReserveRecord[]> {
-  return callBackend("get-payback-reserves");
+  return callBackend("get-payback-reserves", { });
 }
 
 
@@ -166,41 +167,40 @@ export function payback(coinPub: string): Promise<void> {
 }
 
 /**
- * Get an offer stored in the wallet by its offer id.
- * Note that the numeric offer id is not to be confused with
- * the string order_id from the contract terms.
+ * Get a proposal stored in the wallet by its proposal id.
  */
-export function getOffer(offerId: number) {
-  return callBackend("get-offer", { offerId });
+export function getProposal(proposalId: number) {
+  return callBackend("get-proposal", { proposalId });
 }
 
 /**
  * Check if payment is possible or already done.
  */
-export function checkPay(offer: OfferRecord): Promise<CheckPayResult> {
-  return callBackend("check-pay", { offer });
+export function checkPay(proposalId: number): Promise<CheckPayResult> {
+  return callBackend("check-pay", { proposalId });
 }
 
 /**
- * Pay for an offer.
+ * Pay for a proposal.
  */
-export function confirmPay(offer: OfferRecord): Promise<ConfirmPayResult> {
-  return callBackend("confirm-pay", { offer });
+export function confirmPay(proposalId: number): Promise<ConfirmPayResult> {
+  return callBackend("confirm-pay", { proposalId });
 }
 
 /**
  * Hash a contract.  Throws if its not a valid contract.
  */
 export function hashContract(contract: object): Promise<string> {
-  return callBackend("confirm-pay", { contract });
+  return callBackend("hash-contract", { contract });
 }
 
+
 /**
- * Save an offer in the wallet.  Returns the offer id that
- * the offer is stored under.
+ * Save a proposal in the wallet.  Returns the proposal id that
+ * the proposal is stored under.
  */
-export function saveOffer(offer: object): Promise<number> {
-  return callBackend("save-offer", { offer });
+export function saveProposal(proposal: any): Promise<number> {
+  return callBackend("save-proposal", proposal);
 }
 
 /**
@@ -243,7 +243,7 @@ export function paymentFailed(contractTermsHash: string): Promise<void> {
  * cookie was set.
  */
 export function getTabCookie(contractTermsHash: string, merchantSig: string): Promise<any> {
-  return callBackend("get-tab-cookie");
+  return callBackend("get-tab-cookie", { });
 }
 
 /**
@@ -251,5 +251,5 @@ export function getTabCookie(contractTermsHash: string, merchantSig: string): Pr
  * database and return the public key.
  */
 export function generateNonce(): Promise<string> {
-  return callBackend("generate-nonce");
+  return callBackend("generate-nonce", { });
 }
diff --git a/src/webex/wxBackend.ts b/src/webex/wxBackend.ts
index 816ce0251..356b2af6e 100644
--- a/src/webex/wxBackend.ts
+++ b/src/webex/wxBackend.ts
@@ -24,7 +24,6 @@
 /**
  * Imports.
  */
-import { Checkable } from "../checkable";
 import { BrowserHttpLib } from "../http";
 import * as logging from "../logging";
 import {
@@ -34,7 +33,7 @@ import {
 import {
   AmountJson,
   Notifier,
-  OfferRecord,
+  ProposalRecord,
 } from "../types";
 import {
   ConfirmReserveRequest,
@@ -44,6 +43,7 @@ import {
 } from "../wallet";
 
 import { ChromeBadge } from "./chromeBadge";
+import { MessageType } from "./messages";
 
 import URI = require("urijs");
 import Port = chrome.runtime.Port;
@@ -60,21 +60,23 @@ const DB_NAME = "taler";
  */
 const DB_VERSION = 17;
 
-type Handler = (detail: any, sender: MessageSender) => Promise<any>;
-
-function makeHandlers(db: IDBDatabase,
-                      wallet: Wallet): { [msg: string]: Handler } {
-  return {
-    ["balances"]: (detail, sender) => {
+function handleMessage(db: IDBDatabase,
+                       wallet: Wallet,
+                       sender: MessageSender,
+                       type: MessageType, detail: any): any {
+  function assertNotFound(t: never): never {
+    console.error(`Request type ${t as string} unknown`);
+    console.error(`Request detail was ${detail}`);
+    return { error: "request unknown", requestType: type } as never;
+  }
+  switch (type) {
+    case "balances":
       return wallet.getBalances();
-    },
-    ["dump-db"]: (detail, sender) => {
+    case "dump-db":
       return exportDb(db);
-    },
-    ["import-db"]: (detail, sender) => {
+    case "import-db":
       return importDb(db, detail.dump);
-    },
-    ["get-tab-cookie"]: (detail, sender) => {
+    case "get-tab-cookie":
       if (!sender || !sender.tab || !sender.tab.id) {
         return Promise.resolve();
       }
@@ -82,11 +84,9 @@ function makeHandlers(db: IDBDatabase,
       const info: any = paymentRequestCookies[id] as any;
       delete paymentRequestCookies[id];
       return Promise.resolve(info);
-    },
-    ["ping"]: (detail, sender) => {
+    case "ping":
       return Promise.resolve();
-    },
-    ["reset"]: (detail, sender) => {
+    case "reset":
       if (db) {
         const tx = db.transaction(Array.from(db.objectStoreNames), "readwrite");
         // tslint:disable-next-line:prefer-for-of
@@ -95,69 +95,36 @@ function makeHandlers(db: IDBDatabase,
         }
       }
       deleteDb();
-
       chrome.browserAction.setBadgeText({ text: "" });
       console.log("reset done");
-      // Response is synchronous
       return Promise.resolve({});
-    },
-    ["create-reserve"]: (detail, sender) => {
+    case "create-reserve": {
       const d = {
         amount: detail.amount,
         exchange: detail.exchange,
       };
       const req = CreateReserveRequest.checked(d);
       return wallet.createReserve(req);
-    },
-    ["confirm-reserve"]: (detail, sender) => {
-      // TODO: make it a checkable
+    }
+    case "confirm-reserve":
       const d = {
         reservePub: detail.reservePub,
       };
       const req = ConfirmReserveRequest.checked(d);
       return wallet.confirmReserve(req);
-    },
-    ["generate-nonce"]: (detail, sender) => {
+    case "generate-nonce":
       return wallet.generateNonce();
-    },
-    ["confirm-pay"]: (detail, sender) => {
-      let offer: OfferRecord;
-      try {
-        offer = OfferRecord.checked(detail.offer);
-      } catch (e) {
-        if (e instanceof Checkable.SchemaError) {
-          console.error("schema error:", e.message);
-          return Promise.resolve({
-            detail,
-            error: "invalid contract",
-            hint: e.message,
-          });
-        } else {
-          throw e;
-        }
+    case "confirm-pay":
+      if (typeof detail.proposalId !== "number") {
+        throw Error("proposalId must be number");
       }
-
-      return wallet.confirmPay(offer);
-    },
-    ["check-pay"]: (detail, sender) => {
-      let offer: OfferRecord;
-      try {
-        offer = OfferRecord.checked(detail.offer);
-      } catch (e) {
-        if (e instanceof Checkable.SchemaError) {
-          console.error("schema error:", e.message);
-          return Promise.resolve({
-            detail,
-            error: "invalid contract",
-            hint: e.message,
-          });
-        } else {
-          throw e;
-        }
+      return wallet.confirmPay(detail.proposalId);
+    case "check-pay":
+      if (typeof detail.proposalId !== "number") {
+        throw Error("proposalId must be number");
       }
-      return wallet.checkPay(offer);
-    },
-    ["query-payment"]: (detail: any, sender: MessageSender) => {
+      return wallet.checkPay(detail.proposalId);
+    case "query-payment":
       if (sender.tab && sender.tab.id) {
         rateLimitCache[sender.tab.id]++;
         if (rateLimitCache[sender.tab.id] > 10) {
@@ -171,120 +138,98 @@ function makeHandlers(db: IDBDatabase,
         }
       }
       return wallet.queryPayment(detail.url);
-    },
-    ["exchange-info"]: (detail) => {
+    case "exchange-info":
       if (!detail.baseUrl) {
         return Promise.resolve({ error: "bad url" });
       }
       return wallet.updateExchangeFromUrl(detail.baseUrl);
-    },
-    ["currency-info"]: (detail) => {
+    case "currency-info":
       if (!detail.name) {
         return Promise.resolve({ error: "name missing" });
       }
       return wallet.getCurrencyRecord(detail.name);
-    },
-    ["hash-contract"]: (detail) => {
+    case "hash-contract":
       if (!detail.contract) {
         return Promise.resolve({ error: "contract missing" });
       }
       return wallet.hashContract(detail.contract).then((hash) => {
-        return { hash };
+        return hash;
       });
-    },
-    ["put-history-entry"]: (detail: any) => {
+    case "put-history-entry":
       if (!detail.historyEntry) {
         return Promise.resolve({ error: "historyEntry missing" });
       }
       return wallet.putHistory(detail.historyEntry);
-    },
-    ["save-offer"]: (detail: any) => {
-      const offer = detail.offer;
-      if (!offer) {
-        return Promise.resolve({ error: "offer missing" });
-      }
-      console.log("handling safe-offer", detail);
-      // FIXME:  fully migrate to new terminology
-      const checkedOffer = OfferRecord.checked(offer);
-      return wallet.saveOffer(checkedOffer);
-    },
-    ["reserve-creation-info"]: (detail, sender) => {
+    case "save-proposal":
+      console.log("handling save-proposal", detail);
+      const checkedRecord = ProposalRecord.checked({
+        contractTerms: detail.data,
+        contractTermsHash: detail.hash,
+        merchantSig: detail.sig,
+      });
+      return wallet.saveProposal(checkedRecord);
+    case "reserve-creation-info":
       if (!detail.baseUrl || typeof detail.baseUrl !== "string") {
         return Promise.resolve({ error: "bad url" });
       }
       const amount = AmountJson.checked(detail.amount);
       return wallet.getReserveCreationInfo(detail.baseUrl, amount);
-    },
-    ["get-history"]: (detail, sender) => {
+    case "get-history":
       // TODO: limit history length
       return wallet.getHistory();
-    },
-    ["get-offer"]: (detail, sender) => {
-      return wallet.getOffer(detail.offerId);
-    },
-    ["get-exchanges"]: (detail, sender) => {
+    case "get-proposal":
+      return wallet.getProposal(detail.proposalId);
+    case "get-exchanges":
       return wallet.getExchanges();
-    },
-    ["get-currencies"]: (detail, sender) => {
+    case "get-currencies":
       return wallet.getCurrencies();
-    },
-    ["update-currency"]: (detail, sender) => {
+    case "update-currency":
       return wallet.updateCurrency(detail.currencyRecord);
-    },
-    ["get-reserves"]: (detail, sender) => {
+    case "get-reserves":
       if (typeof detail.exchangeBaseUrl !== "string") {
         return Promise.reject(Error("exchangeBaseUrl missing"));
       }
       return wallet.getReserves(detail.exchangeBaseUrl);
-    },
-    ["get-payback-reserves"]: (detail, sender) => {
+    case "get-payback-reserves":
       return wallet.getPaybackReserves();
-    },
-    ["withdraw-payback-reserve"]: (detail, sender) => {
+    case "withdraw-payback-reserve":
       if (typeof detail.reservePub !== "string") {
         return Promise.reject(Error("reservePub missing"));
       }
       return wallet.withdrawPaybackReserve(detail.reservePub);
-    },
-    ["get-coins"]: (detail, sender) => {
+    case "get-coins":
       if (typeof detail.exchangeBaseUrl !== "string") {
         return Promise.reject(Error("exchangBaseUrl missing"));
       }
       return wallet.getCoins(detail.exchangeBaseUrl);
-    },
-    ["get-precoins"]: (detail, sender) => {
+    case "get-precoins":
       if (typeof detail.exchangeBaseUrl !== "string") {
         return Promise.reject(Error("exchangBaseUrl missing"));
       }
       return wallet.getPreCoins(detail.exchangeBaseUrl);
-    },
-    ["get-denoms"]: (detail, sender) => {
+    case "get-denoms":
       if (typeof detail.exchangeBaseUrl !== "string") {
         return Promise.reject(Error("exchangBaseUrl missing"));
       }
       return wallet.getDenoms(detail.exchangeBaseUrl);
-    },
-    ["refresh-coin"]: (detail, sender) => {
+    case "refresh-coin":
       if (typeof detail.coinPub !== "string") {
         return Promise.reject(Error("coinPub missing"));
       }
       return wallet.refresh(detail.coinPub);
-    },
-    ["payback-coin"]: (detail, sender) => {
+    case "payback-coin":
       if (typeof detail.coinPub !== "string") {
         return Promise.reject(Error("coinPub missing"));
       }
       return wallet.payback(detail.coinPub);
-    },
-    ["payment-failed"]: (detail, sender) => {
+    case "payment-failed":
       // For now we just update exchanges (maybe the exchange did something
       // wrong and the keys were messed up).
       // FIXME: in the future we should look at what actually went wrong.
       console.error("payment reported as failed");
       wallet.updateExchanges();
       return Promise.resolve();
-    },
-    ["payment-succeeded"]: (detail, sender) => {
+    case "payment-succeeded":
       const contractTermsHash = detail.contractTermsHash;
       const merchantSig = detail.merchantSig;
       if (!contractTermsHash) {
@@ -294,24 +239,16 @@ function makeHandlers(db: IDBDatabase,
         return Promise.reject(Error("merchantSig missing"));
       }
       return wallet.paymentSucceeded(contractTermsHash, merchantSig);
-    },
-  };
-}
-
-
-async function dispatch(handlers: any, req: any, sender: any, sendResponse: any): Promise<void> {
-  if (!(req.type in handlers)) {
-    console.error(`Request type ${req.type} unknown`);
-    console.error(`Request was ${req}`);
-    try {
-      sendResponse({ error: "request unknown", requestType: req.type });
-    } catch (e) {
-      // might fail if tab disconnected
-    }
+    default:
+      // Exhaustiveness check.
+      // See https://www.typescriptlang.org/docs/handbook/advanced-types.html
+      return assertNotFound(type);
   }
+}
 
+async function dispatch(db: IDBDatabase, wallet: Wallet, req: any, sender: any, sendResponse: any): Promise<void> {
   try {
-    const p = handlers[req.type](req.detail, sender);
+    const p = handleMessage(db, wallet, sender, req.type, req.detail);
     const r = await p;
     try {
       sendResponse(r);
@@ -587,9 +524,8 @@ export async function wxMain() {
 
   // Handlers for messages coming directly from the content
   // script on the page
-  const handlers = makeHandlers(db, wallet!);
   chrome.runtime.onMessage.addListener((req, sender, sendResponse) => {
-    dispatch(handlers, req, sender, sendResponse);
+    dispatch(db, wallet, req, sender, sendResponse);
     return true;
   });