From 9e68605a3499b414e846518a1170e74bd2d50ed0 Mon Sep 17 00:00:00 2001
From: Henrique Leite <contact.henriqueleite42@gmail.com>
Date: Fri, 24 Nov 2023 14:27:42 -0300
Subject: [PATCH] Add support for multiple relationships with the same type

---
 .vscode/settings.json    |  3 ++-
 components/ModelNode.tsx |  1 +
 util/prismaToFlow.ts     | 22 ++++++++++++++++------
 3 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/.vscode/settings.json b/.vscode/settings.json
index 11ace4d..d5b7579 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -1,4 +1,5 @@
 {
   "typescript.tsdk": "node_modules\\typescript\\lib",
-  "css.lint.unknownAtRules": "ignore"
+  "css.lint.unknownAtRules": "ignore",
+  "cSpell.words": ["datamodel", "DMMF", "reactflow", "Virtuals"]
 }
diff --git a/components/ModelNode.tsx b/components/ModelNode.tsx
index b0741d5..d177cb9 100644
--- a/components/ModelNode.tsx
+++ b/components/ModelNode.tsx
@@ -78,6 +78,7 @@ const ModelNode = ({ data }: ModelNodeProps) => {
             const targetHandleId = relationEdgeTargetHandleId(
               data.name,
               col.relationData.name,
+              col.name,
             );
             const sourceHandleId = relationEdgeSourceHandleId(
               data.name,
diff --git a/util/prismaToFlow.ts b/util/prismaToFlow.ts
index a08659a..0b3f50f 100644
--- a/util/prismaToFlow.ts
+++ b/util/prismaToFlow.ts
@@ -70,9 +70,11 @@ export const relationEdgeSourceHandleId = (
   column: string,
 ) => `${table}-${relation}-${column}`;
 
-// TODO: might need to include column name for multiple relations of same type??
-export const relationEdgeTargetHandleId = (table: string, relation: string) =>
-  `${table}-${relation}`;
+export const relationEdgeTargetHandleId = (
+  table: string,
+  relation: string,
+  column: string,
+) => `${table}-${relation}-${column}`;
 
 const virtualTableName = (relation: string, table: string) =>
   `${relation}-${table}`;
@@ -231,7 +233,12 @@ const relationsToEdges = (
     };
 
     const source = rel.fields.find((f) => f.side === "source")!;
-    const target = rel.fields.find((f) => f.side === "target")!;
+    let target = rel.fields.find((f) => f.side === "target");
+
+    if (!target && rel.virtual)
+      target = rel.fields.find((f) => f.tableName === rel.virtual?.name);
+
+    if (!target) throw new Error("Invalid target");
 
     result.push({
       ...base,
@@ -242,9 +249,12 @@ const relationsToEdges = (
         rel.name,
         source.name,
       ),
-      targetHandle: relationEdgeTargetHandleId(target.tableName, rel.name),
+      targetHandle: relationEdgeTargetHandleId(
+        target.tableName,
+        rel.name,
+        target.name,
+      ),
     });
-    // }
   }
 
   return result;