you can't add an existing invoice.

src/clj/auto_ap/db/invoices.clj

@@ -63,6 +63,15 @@
 (defn get-all []
   (query base-query))
 
+(defn find-conflicting [{:keys [id invoice-number company-id vendor-id]}]
+  (query
+   (-> base-query
+       (helpers/merge-where [:and [:not= :id id]
+                             [:= :invoice-number invoice-number]
+                             [:= :company-id company-id]
+                             [:= :vendor-id vendor-id]
+                             [:not= :status "voided"]]))))
+
 (defn get-multi [ids]
   (query (-> base-query
              (helpers/merge-where [:in :id ids]))))

src/clj/auto_ap/graphql/invoices.clj

@@ -13,6 +13,10 @@
     (vendors/insert {:name vendor-name :default-expense-account 0})))
 
 (defn add-invoice [context {{:keys [total invoice_number location company_id vendor_id vendor_name date] :as in} :invoice} value]
+  (when (seq (invoices/find-conflicting {:invoice-number invoice_number
+                                         :vendor-id vendor_id
+                                         :company-id company_id}))
+    (throw (ex-info "that invoice already exists" {:invoice-number invoice_number})))
   (let [vendor (-create-or-get-vendor vendor_id vendor_name)
         _ (assert-can-see-company (:id context) company_id)
         company (companies/get-by-id company_id)

src/cljs/auto_ap/events.cljs

@@ -85,6 +85,14 @@
    (println "changing modal status" id "to")
    (update-in db [:modal-state id] #(merge % state))))
 
+(re-frame/reg-event-db
+ ::modal-failed
+ (fn  [db [_ id  message]]
+   (println "CURRENT" (get-in db [:modal-state]))
+   (-> db
+       (assoc-in [:modal-state id :saving?] false)
+       (assoc-in [:modal-state id :error-message] message))))
+
 (re-frame/reg-event-db
  ::modal-completed
  (fn  [db [_ id  state]]

src/cljs/auto_ap/views/components/modal.cljs

@@ -22,9 +22,10 @@
        foot])]])
 
 (defn action-modal [{:keys [title action-text id save-event can-submit?] :or {can-submit? true}} & rest]
-  (let [{:keys [visible? saving?]} @(re-frame/subscribe [::subs/modal-state id])]
+  (let [{:keys [visible? saving? error-message]} @(re-frame/subscribe [::subs/modal-state id])]
     (when visible?
-      (-> [modal {:title title
+      (-> [modal {:title [:span title
+                          ]
                   :foot [:input.button.is-primary {:type "submit"
                                                    :tab-index "0"
                                                    :form id
@@ -45,7 +46,10 @@
            (into [:form {:id id
                          :on-submit (fn [e]
                                       (.preventDefault e)
-                                      (re-frame/dispatch [::events/modal-status id {:saving? true}])
-                                      (re-frame/dispatch save-event))}]
+                                      (re-frame/dispatch [::events/modal-status id {:saving? true :error-message nil}])
+                                      (re-frame/dispatch save-event))}
+                  (when error-message
+                    [:div.notification.is-warning error-message])]
+
                  (r/children (r/current-component)) )]
           (into [(when saving? [:div.is-overlay {:style {"backgroundColor" "rgba(150,150,150, 0.5)"}}])])))))

src/cljs/auto_ap/views/pages/unpaid_invoices.cljs

@@ -259,7 +259,8 @@
                                                                       :location
                                                                       [:expense_account [:id :name [:parent [:id :name]]]]]]
                                                   ]]}]}  
-       :on-success [::invoice-created]}})))
+       :on-success [::invoice-created]
+       :on-error [::invoice-create-failed]}})))
 
 (re-frame/reg-event-fx
  ::edit-invoice-save
@@ -331,6 +332,11 @@
                                 invoices)))
               (dissoc ::handwrite-checks))})))
 
+(re-frame/reg-event-fx
+ ::invoice-create-failed
+ (fn [{:keys [db]} [_ data]]
+   {:dispatch [::events/modal-failed ::new-invoice "That invoice already exists."]}))
+
 (re-frame/reg-event-fx
  ::invoice-created
  (fn [{:keys [db]} [_ {:keys [add-invoice]}]]