From 06b049f0ff3d97a1933f0ef3acecee269391adde Mon Sep 17 00:00:00 2001
From: Josha von Gizycki <josha.von.gizycki@triology.de>
Date: Tue, 8 Jan 2019 20:08:18 +0100
Subject: [PATCH] creating links between instances

---
 src/wanijo/instance/domain.clj | 14 ++++++++++++++
 src/wanijo/instance/forms.clj  |  9 +++++++++
 src/wanijo/instance/routes.clj | 34 ++++++++++++++++++++++++++++++++--
 src/wanijo/instance/view.clj   | 28 ++++++++++++++++++++++++++--
 4 files changed, 81 insertions(+), 4 deletions(-)

diff --git a/src/wanijo/instance/domain.clj b/src/wanijo/instance/domain.clj
index 805de03..beea3ec 100644
--- a/src/wanijo/instance/domain.clj
+++ b/src/wanijo/instance/domain.clj
@@ -122,3 +122,17 @@
 
 (defn delete! [uuid]
   (neo4j/exec-query! delete {:uuid uuid}))
+
+(neo4j/defquery create-link
+  "MATCH (i:instance {uuid:{instance_uuid}}),
+         (i2)
+   WHERE i2.uuid IN {instance_uuids}
+   CREATE (i)-[:link {name:{name},
+                      created_at:{created_at}}]->(i2)")
+
+(defn create-link! [instance-uuid name instance-uuids]
+  (neo4j/exec-query! create-link
+                     {:instance_uuid instance-uuid
+                      :name name
+                      :created_at (neo4j/now-str)
+                      :instance_uuids instance-uuids}))
diff --git a/src/wanijo/instance/forms.clj b/src/wanijo/instance/forms.clj
index 01e452a..0417cb5 100644
--- a/src/wanijo/instance/forms.clj
+++ b/src/wanijo/instance/forms.clj
@@ -6,6 +6,15 @@
                    :required true
                    :spec ::domain/name}}})
 
+(defn link-form [instances]
+  {:fields {:name {:label "Name"
+                   :required true}
+            :instances {:label "Instances"
+                        :widget :mselect
+                        :options (map #(vector (:name %)
+                                               (:uuid %))
+                                      instances)}}})
+
 (defn attr-type->widget [attr-type]
   (case attr-type
     ("markdown" "text") :textarea
diff --git a/src/wanijo/instance/routes.clj b/src/wanijo/instance/routes.clj
index 2f0acbe..15cd3b3 100644
--- a/src/wanijo/instance/routes.clj
+++ b/src/wanijo/instance/routes.clj
@@ -48,10 +48,12 @@
 
 (defn edit-form! [uuid req]
   (let [instance (instance! uuid)
-        attrs (domain-attr/find-by-instance! uuid)]
+        attrs (domain-attr/find-by-instance! uuid)
+        user-uuid (get-in req [:session :uuid])]
     (view/edit! instance
                 (form! uuid)
                 (forms-inst/instance->form-data instance)
+                (domain-schema/accessible-schemas! user-uuid)
                 req)))
 
 (defn edit! [uuid req]
@@ -72,6 +74,26 @@
     (resp/redirect (path :instance-list
                          {:schema-uuid (:uuid schema)}))))
 
+(defn link-form! [schema-uuid]
+  (forms-inst/link-form
+   (domain/find-by-schema! schema-uuid)))
+
+(defn link-selection! [uuid schema-uuid req]
+  (view/link-selection (instance! uuid)
+                       (domain-schema/find-by-uuid! schema-uuid)
+                       (link-form! schema-uuid)
+                       req))
+
+(defn create-link! [uuid schema-uuid req]
+  (let [form (link-form! schema-uuid)]
+    (if (form/valid? form req)
+      (let [form-data (form/form-data form req)]
+        (domain/create-link! uuid
+                             (:name form-data)
+                             (:instances form-data))
+        (resp/redirect (path :instance-show {:uuid uuid})))
+      (link-selection! uuid schema-uuid req))))
+
 (defroutes routes
   (wrap-routes
    (GET (register! :instance-list "/instance/list/:schema-uuid")
@@ -92,4 +114,12 @@
         (edit! uuid req))
   (DELETE (register! :instance-delete "/instance/:uuid")
           [uuid :as req]
-          (delete! uuid req)))
+          (delete! uuid req))
+  (GET (register! :instance-link-selection
+                  "/instance/:uuid/link/:schema-uuid")
+       [uuid schema-uuid :as req]
+       (link-selection! uuid schema-uuid req))
+  (POST (register! :instance-create-link
+                   "/instance/:uuid/link/:schema-uuid")
+        [uuid schema-uuid :as req]
+        (create-link! uuid schema-uuid req)))
diff --git a/src/wanijo/instance/view.clj b/src/wanijo/instance/view.clj
index 7533475..4c18005 100644
--- a/src/wanijo/instance/view.clj
+++ b/src/wanijo/instance/view.clj
@@ -62,7 +62,7 @@
                                "attr-type-" type)}
              (render-fn (:value prop))]))]))
 
-(defn edit! [instance form form-data req]
+(defn edit! [instance form form-data schemas req]
   (view/layout!
    :request req
    :content
@@ -70,9 +70,33 @@
      (h (-> instance :schema :name))
      "&nbsp;"
      [:small (h (:name instance))]]
+    [:h2 "Edit Instance"]
     (hform/form-to [:post (path :instance-edit instance)]
                    (form/render-widgets form form-data req)
                    (hform/submit-button "Edit!"))
     (hform/form-to [:delete (path :instance-delete instance)]
                    (anti-forgery-field)
-                   (view/delete-btn))]))
+                   (view/delete-btn))
+    [:h2 "Link Instance with Instance of Schema..."]
+    [:ul
+     (for [schema schemas]
+       [:li
+        [:a {:href (path :instance-link-selection
+                         {:uuid (:uuid instance)
+                          :schema-uuid (:uuid schema)})}
+         (h (:name schema))]])]]))
+
+(defn link-selection [instance schema form req]
+  (view/layout!
+   :request req
+   :content
+   [[:h1
+     [:small "Link " (-> instance :schema :name) " "]
+     (h (:name instance))
+     [:small " with "]
+     (h (:name schema))]
+    (hform/form-to [:post (path :instance-create-link
+                                {:uuid (:uuid instance)
+                                 :schema-uuid (:uuid schema)})]
+                   (form/render-widgets form nil req)
+                   (hform/submit-button "Link!"))]))