From 814a78ba4627b39fb7b003527f14ee31733ccd8a Mon Sep 17 00:00:00 2001
From: Ryan McKinley <ryantxu@gmail.com>
Date: Fri, 22 Oct 2021 09:16:32 -0700
Subject: [PATCH] Value mappings: scroll values when many items exist (#40733)

---
 .../grafana-ui/src/components/Modal/Modal.tsx |  17 ++-
 .../ValueMappingsEditorModal.test.tsx         |   4 +-
 .../ValueMappingsEditorModal.tsx              | 106 +++++++++++-------
 .../components/ValuePicker/ValuePicker.tsx    |  32 +++---
 .../PanelEditor/getFieldOverrideElements.tsx  |   1 +
 5 files changed, 101 insertions(+), 59 deletions(-)

diff --git a/packages/grafana-ui/src/components/Modal/Modal.tsx b/packages/grafana-ui/src/components/Modal/Modal.tsx
index bdc734687d1..c92377aca91 100644
--- a/packages/grafana-ui/src/components/Modal/Modal.tsx
+++ b/packages/grafana-ui/src/components/Modal/Modal.tsx
@@ -89,10 +89,25 @@ export function Modal(props: PropsWithChildren<Props>) {
   );
 }
 
-function ModalButtonRow({ children }: { children: React.ReactNode }) {
+function ModalButtonRow({ leftItems, children }: { leftItems?: React.ReactNode; children: React.ReactNode }) {
   const theme = useTheme2();
   const styles = getModalStyles(theme);
 
+  if (leftItems) {
+    return (
+      <div className={styles.modalButtonRow}>
+        <HorizontalGroup justify="space-between">
+          <HorizontalGroup justify="flex-start" spacing="md">
+            {leftItems}
+          </HorizontalGroup>
+          <HorizontalGroup justify="flex-end" spacing="md">
+            {children}
+          </HorizontalGroup>
+        </HorizontalGroup>
+      </div>
+    );
+  }
+
   return (
     <div className={styles.modalButtonRow}>
       <HorizontalGroup justify="flex-end" spacing="md">
diff --git a/packages/grafana-ui/src/components/ValueMappingsEditor/ValueMappingsEditorModal.test.tsx b/packages/grafana-ui/src/components/ValueMappingsEditor/ValueMappingsEditorModal.test.tsx
index da80804f835..9c961ded1ad 100644
--- a/packages/grafana-ui/src/components/ValueMappingsEditor/ValueMappingsEditorModal.test.tsx
+++ b/packages/grafana-ui/src/components/ValueMappingsEditor/ValueMappingsEditorModal.test.tsx
@@ -121,6 +121,7 @@ describe('When adding and updating range map', () => {
   it('should add new range map', async () => {
     const onChangeSpy = jest.fn();
     setup(onChangeSpy, { value: [] });
+    screen.getAllByTestId('remove-value-mapping')[0].click();
 
     fireEvent.click(screen.getByLabelText(selectors.components.ValuePicker.button('Add a new mapping')));
     const selectComponent = await screen.findByLabelText(selectors.components.ValuePicker.select('Add a new mapping'));
@@ -148,10 +149,11 @@ describe('When adding and updating range map', () => {
   });
 });
 
-describe('When adding and updating tegex map', () => {
+describe('When adding and updating regex map', () => {
   it('should add new regex map', async () => {
     const onChangeSpy = jest.fn();
     setup(onChangeSpy, { value: [] });
+    screen.getAllByTestId('remove-value-mapping')[0].click();
 
     fireEvent.click(screen.getByLabelText(selectors.components.ValuePicker.button('Add a new mapping')));
     const selectComponent = await screen.findByLabelText(selectors.components.ValuePicker.select('Add a new mapping'));
diff --git a/packages/grafana-ui/src/components/ValueMappingsEditor/ValueMappingsEditorModal.tsx b/packages/grafana-ui/src/components/ValueMappingsEditor/ValueMappingsEditorModal.tsx
index 4feae052e3d..1951015bb67 100644
--- a/packages/grafana-ui/src/components/ValueMappingsEditor/ValueMappingsEditorModal.tsx
+++ b/packages/grafana-ui/src/components/ValueMappingsEditor/ValueMappingsEditorModal.tsx
@@ -81,51 +81,65 @@ export function ValueMappingsEditorModal({ value, onChange, onClose }: Props) {
     onClose();
   };
 
+  // Start with an empty row
+  useEffect(() => {
+    if (!value?.length) {
+      onAddValueMapping({ value: MappingType.ValueToText });
+    }
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, []);
+
   return (
     <>
-      <table className={styles.editTable}>
-        <thead>
-          <tr>
-            <th style={{ width: '1%' }}></th>
-            <th style={{ width: '40%', textAlign: 'left' }} colSpan={2}>
-              Condition
-            </th>
-            <th style={{ textAlign: 'left' }}>Display text</th>
-            <th style={{ width: '10%' }}>Color</th>
-            <th style={{ width: '1%' }}></th>
-          </tr>
-        </thead>
-        <DragDropContext onDragEnd={onDragEnd}>
-          <Droppable droppableId="sortable-field-mappings" direction="vertical">
-            {(provided) => (
-              <tbody ref={provided.innerRef} {...provided.droppableProps}>
-                {rows.map((row, index) => (
-                  <ValueMappingEditRow
-                    key={index.toString()}
-                    mapping={row}
-                    index={index}
-                    onChange={onChangeMapping}
-                    onRemove={onRemoveRow}
-                    onDuplicate={onDuplicateMapping}
-                  />
-                ))}
-                {provided.placeholder}
-              </tbody>
-            )}
-          </Droppable>
-        </DragDropContext>
-      </table>
-      <ValuePicker
-        label="Add a new mapping"
-        variant="secondary"
-        size="md"
-        icon="plus"
-        menuPlacement="auto"
-        isFullWidth={false}
-        options={mappingTypes}
-        onChange={onAddValueMapping}
-      />
-      <Modal.ButtonRow>
+      <div className={styles.tableWrap}>
+        <table className={styles.editTable}>
+          <thead>
+            <tr>
+              <th style={{ width: '1%' }}></th>
+              <th style={{ width: '40%', textAlign: 'left' }} colSpan={2}>
+                Condition
+              </th>
+              <th style={{ textAlign: 'left' }}>Display text</th>
+              <th style={{ width: '10%' }}>Color</th>
+              <th style={{ width: '1%' }}></th>
+            </tr>
+          </thead>
+          <DragDropContext onDragEnd={onDragEnd}>
+            <Droppable droppableId="sortable-field-mappings" direction="vertical">
+              {(provided) => (
+                <tbody ref={provided.innerRef} {...provided.droppableProps}>
+                  {rows.map((row, index) => (
+                    <ValueMappingEditRow
+                      key={index.toString()}
+                      mapping={row}
+                      index={index}
+                      onChange={onChangeMapping}
+                      onRemove={onRemoveRow}
+                      onDuplicate={onDuplicateMapping}
+                    />
+                  ))}
+                  {provided.placeholder}
+                </tbody>
+              )}
+            </Droppable>
+          </DragDropContext>
+        </table>
+      </div>
+
+      <Modal.ButtonRow
+        leftItems={
+          <ValuePicker
+            label="Add a new mapping"
+            variant="secondary"
+            size="md"
+            icon="plus"
+            menuPlacement="auto"
+            minWidth={40}
+            options={mappingTypes}
+            onChange={onAddValueMapping}
+          />
+        }
+      >
         <Button variant="secondary" fill="outline" onClick={onClose}>
           Cancel
         </Button>
@@ -138,6 +152,12 @@ export function ValueMappingsEditorModal({ value, onChange, onClose }: Props) {
 }
 
 export const getStyles = (theme: GrafanaTheme2) => ({
+  tableWrap: css`
+    max-height: calc(80vh - 170px);
+    min-height: 40px;
+    overflow: auto;
+  `,
+
   editTable: css({
     width: '100%',
     marginBottom: theme.spacing(2),
diff --git a/packages/grafana-ui/src/components/ValuePicker/ValuePicker.tsx b/packages/grafana-ui/src/components/ValuePicker/ValuePicker.tsx
index becb214cf7a..53c68bcb47f 100644
--- a/packages/grafana-ui/src/components/ValuePicker/ValuePicker.tsx
+++ b/packages/grafana-ui/src/components/ValuePicker/ValuePicker.tsx
@@ -3,9 +3,9 @@ import { IconName } from '../../types';
 import { SelectableValue } from '@grafana/data';
 import { Button, ButtonVariant } from '../Button';
 import { Select } from '../Select/Select';
-import { FullWidthButtonContainer } from '../Button/FullWidthButtonContainer';
 import { ComponentSize } from '../../types/size';
 import { selectors } from '@grafana/e2e-selectors';
+import { useTheme2 } from '../../themes';
 
 export interface ValuePickerProps<T> {
   /** Label to display on the picker button */
@@ -20,6 +20,8 @@ export interface ValuePickerProps<T> {
   variant?: ButtonVariant;
   /** Size of button  */
   size?: ComponentSize;
+  /** Min width for select in grid units */
+  minWidth?: number;
   /** Should the picker cover the full width of its parent */
   isFullWidth?: boolean;
   /** Control where the menu is rendered */
@@ -32,29 +34,31 @@ export function ValuePicker<T>({
   options,
   onChange,
   variant,
+  minWidth = 16,
   size = 'sm',
   isFullWidth = true,
   menuPlacement,
 }: ValuePickerProps<T>) {
   const [isPicking, setIsPicking] = useState(false);
+  const theme = useTheme2();
 
-  const buttonEl = (
-    <Button
-      size={size || 'sm'}
-      icon={icon || 'plus'}
-      onClick={() => setIsPicking(true)}
-      variant={variant}
-      aria-label={selectors.components.ValuePicker.button(label)}
-    >
-      {label}
-    </Button>
-  );
   return (
     <>
-      {!isPicking && (isFullWidth ? <FullWidthButtonContainer>{buttonEl}</FullWidthButtonContainer> : buttonEl)}
+      {!isPicking && (
+        <Button
+          size={size || 'sm'}
+          icon={icon || 'plus'}
+          onClick={() => setIsPicking(true)}
+          variant={variant}
+          fullWidth={isFullWidth}
+          aria-label={selectors.components.ValuePicker.button(label)}
+        >
+          {label}
+        </Button>
+      )}
 
       {isPicking && (
-        <span>
+        <span style={{ minWidth: theme.spacing(minWidth), flexGrow: isFullWidth ? 1 : undefined }}>
           <Select
             menuShouldPortal
             placeholder={label}
diff --git a/public/app/features/dashboard/components/PanelEditor/getFieldOverrideElements.tsx b/public/app/features/dashboard/components/PanelEditor/getFieldOverrideElements.tsx
index 1be7012d2f2..ad99f9609bc 100644
--- a/public/app/features/dashboard/components/PanelEditor/getFieldOverrideElements.tsx
+++ b/public/app/features/dashboard/components/PanelEditor/getFieldOverrideElements.tsx
@@ -260,5 +260,6 @@ function getBorderTopStyles(theme: GrafanaTheme2) {
   return css({
     borderTop: `1px solid ${theme.colors.border.weak}`,
     padding: `${theme.spacing(2)}`,
+    display: 'flex',
   });
 }