From 8e48be58efe9bfffd0f3f5af098ef2a4cefc4b2d Mon Sep 17 00:00:00 2001
From: Kasper Fabricius Kristensen
 <45367945+kasperkristensen@users.noreply.github.com>
Date: Thu, 2 Nov 2023 13:03:45 +0100
Subject: [PATCH] fix(admin-ui): Make regions in tax setting scrollable (#5530)

* fix overflow

* intersection observer and changeset
---
 .changeset/plenty-coins-smell.md              |   5 +
 .../ui/src/domain/settings/taxes/index.tsx    | 102 ++++++++++++++----
 2 files changed, 85 insertions(+), 22 deletions(-)
 create mode 100644 .changeset/plenty-coins-smell.md

diff --git a/.changeset/plenty-coins-smell.md b/.changeset/plenty-coins-smell.md
new file mode 100644
index 0000000000000..8862e0742a3d5
--- /dev/null
+++ b/.changeset/plenty-coins-smell.md
@@ -0,0 +1,5 @@
+---
+"@medusajs/admin-ui": patch
+---
+
+fix(admin-ui): Fixes an issue where regions were not scrollable in tax settings view, also adds a IntersectionObserver to ensure that we load all regions as the user scrolls. The current implementation was capped at loading 20 regions.
diff --git a/packages/admin-ui/ui/src/domain/settings/taxes/index.tsx b/packages/admin-ui/ui/src/domain/settings/taxes/index.tsx
index 484f402c0ae9e..ab2084b6f8231 100644
--- a/packages/admin-ui/ui/src/domain/settings/taxes/index.tsx
+++ b/packages/admin-ui/ui/src/domain/settings/taxes/index.tsx
@@ -1,23 +1,76 @@
+import { Region } from "@medusajs/medusa"
 import { useAdminRegions } from "medusa-react"
-import { useCallback, useEffect, useState } from "react"
-import { useNavigate, useParams } from "react-router-dom"
+import { useCallback, useEffect, useRef, useState } from "react"
 import { useTranslation } from "react-i18next"
+import { useNavigate, useParams } from "react-router-dom"
 import BackButton from "../../../components/atoms/back-button"
-import Spinner from "../../../components/atoms/spinner"
 import GearIcon from "../../../components/fundamentals/icons/gear-icon"
 import BodyCard from "../../../components/organisms/body-card"
 import RadioGroup from "../../../components/organisms/radio-group"
 import TwoSplitPane from "../../../components/templates/two-split-pane"
 import TaxDetails from "./details"
 
+const LIMIT = 20
+
 const Taxes = () => {
   const params = useParams()
   const regId: string | undefined = params["*"]
 
+  const [offset, setOffset] = useState(0)
+  const observerRef = useRef<HTMLDivElement>(null)
+
   const navigate = useNavigate()
   const { t } = useTranslation()
 
-  const { regions, isLoading } = useAdminRegions()
+  const [regionOpts, setRegionOpts] = useState<Region[]>([])
+
+  const { regions, count, isLoading } = useAdminRegions({
+    offset,
+    limit: LIMIT,
+  })
+
+  useEffect(() => {
+    if (regions && !isLoading) {
+      setRegionOpts((prev) => {
+        const exisitngIds = prev.map((r) => r.id)
+        const newOpts = regions.filter((r) => !exisitngIds.includes(r.id))
+
+        return [...prev, ...newOpts]
+      })
+    }
+  }, [regions, isLoading])
+
+  useEffect(() => {
+    const current = observerRef.current
+
+    const observer = new IntersectionObserver(
+      (entries) => {
+        // If the ref is in view and there's more data to fetch
+        if (
+          entries[0].isIntersecting &&
+          regionOpts &&
+          regionOpts.length < (count || 0)
+        ) {
+          setOffset(regionOpts.length)
+        }
+      },
+      {
+        root: null, // relative to the viewport
+        threshold: 1.0, // trigger when 100% of the ref is visible
+      }
+    )
+
+    if (current) {
+      observer.observe(current)
+    }
+
+    // Clean up the observer on component unmount
+    return () => {
+      if (current) {
+        observer.unobserve(current)
+      }
+    }
+  }, [count, regionOpts])
 
   const [selectedRegion, setSelectedRegion] = useState<string | undefined>(
     regId
@@ -71,35 +124,40 @@ const Taxes = () => {
                 onClick: () => navigate("/a/settings/regions"),
               },
             ]}
+            className="no-scrollbar overflow-y-auto"
           >
-            {isLoading || !regions ? (
-              <div className="flex h-full flex-grow items-center justify-center">
-                <Spinner size="large" variant="secondary" />
-              </div>
-            ) : (
+            <div>
               <RadioGroup.Root
                 value={selectedRegion}
                 onValueChange={handleChange}
               >
-                {regions.map((r) => {
+                {regionOpts.map((r, index) => {
                   return (
-                    <RadioGroup.Item
-                      label={r.name}
-                      description={
-                        r.countries.length
-                          ? `${r.countries
-                              .map((c) => c.display_name)
-                              .join(", ")}`
+                    <div
+                      key={r.id}
+                      ref={
+                        index === regionOpts.length - 1
+                          ? observerRef
                           : undefined
                       }
-                      value={r.id}
-                      key={r.id}
-                      id={r.id}
-                    />
+                    >
+                      <RadioGroup.Item
+                        label={r.name}
+                        description={
+                          r.countries.length
+                            ? `${r.countries
+                                .map((c) => c.display_name)
+                                .join(", ")}`
+                            : undefined
+                        }
+                        value={r.id}
+                        key={r.id}
+                      />
+                    </div>
                   )
                 })}
               </RadioGroup.Root>
-            )}
+            </div>
           </BodyCard>
           <TaxDetails id={selectedRegion} />
         </TwoSplitPane>