fix(categoryCombo): add validation and errors for categorycombo

src/components/metadataFormControls/ModelTransfer/BaseModelTransfer.tsx

@@ -58,6 +58,7 @@ export const BaseModelTransfer = <TModel extends DisplayableModel>({
 
     return (
         <Transfer
+            maxSelections={5000}
             {...transferProps}
             selected={selectedTransferValues}
             options={allTransferOptions}

src/lib/form/modelFormSchemas.ts

@@ -33,4 +33,5 @@ export const modelFormSchemas = {
     identifiable,
     attributeValues,
     withAttributeValues,
+    modelReference,
 }

src/pages/categoryCombos/form/CategoriesField.tsx

@@ -0,0 +1,153 @@
+import i18n from '@dhis2/d2-i18n'
+import { Field, NoticeBox } from '@dhis2/ui'
+import React from 'react'
+import { useField } from 'react-final-form'
+import { NavLink, useParams } from 'react-router-dom'
+import { ModelTransfer } from '../../../components'
+import { DisplayableModel } from '../../../types/models'
+import css from './CategoryCombo.module.css'
+import { CategoryComboFormValues } from './categoryComboSchema'
+import { useIdenticalCategoryCombosQuery } from './useIdenticalCategoryCombosQuery'
+
+type CategoriesValue = Pick<CategoryComboFormValues, 'categories'>['categories']
+
+const query = {
+    resource: 'categories',
+    params: {
+        fields: [
+            'id',
+            'displayName',
+            'categoryOptions~size~rename(categoryOptionsSize)',
+        ],
+        order: 'displayName:asc',
+        filter: ['name:ne:default'],
+    },
+}
+
+const fieldName = 'categories'
+const numberFormat = new Intl.NumberFormat()
+
+export function CategoriesField() {
+    const catComboId = useParams()?.id
+
+    const { input, meta } = useField<
+        Pick<CategoryComboFormValues, 'categories'>['categories']
+    >(fieldName, {
+        multiple: true,
+        validateFields: [],
+    })
+
+    const generatedCocsCount =
+        input.value?.reduce((acc, cat) => acc * cat.categoryOptionsSize, 1) || 0
+    return (
+        <div className={css.categoriesFieldWrapper}>
+            <Field
+                dataTest="formfields-modeltransfer"
+                error={meta.invalid}
+                validationText={(meta.touched && meta.error?.toString()) || ''}
+                name={fieldName}
+            >
+                <ModelTransfer
+                    selected={input.value}
+                    onChange={({ selected }) => {
+                        input.onChange(selected)
+                        input.onBlur()
+                    }}
+                    leftHeader={i18n.t('Available categories')}
+                    rightHeader={i18n.t('Selected categories')}
+                    filterPlaceholder={i18n.t('Filter available categories')}
+                    filterPlaceholderPicked={i18n.t(
+                        'Filter selected categories'
+                    )}
+                    query={query}
+                    maxSelections={200}
+                />
+            </Field>
+            <div className={css.categoriesNoticesWrapper}>
+                {!catComboId && generatedCocsCount > 1 && (
+                    <NoticeBox warning={generatedCocsCount > 250}>
+                        {i18n.t(
+                            '{{count}} category option combinations will be generated.',
+                            {
+                                count: numberFormat.format(generatedCocsCount),
+                            }
+                        )}
+                    </NoticeBox>
+                )}
+                <CategoriesFieldWarnings
+                    catComboId={catComboId}
+                    selectedCategories={input.value}
+                />
+            </div>
+        </div>
+    )
+}
+
+const CategoriesFieldWarnings = ({
+    selectedCategories,
+    catComboId,
+}: {
+    selectedCategories: CategoriesValue
+    catComboId?: string
+}) => {
+    const isMoreThanRecommended = selectedCategories.length > 4
+    const identicalCatCombosResult = useIdenticalCategoryCombosQuery({
+        categoryComboId: catComboId,
+        selectedCategories,
+        enabled: !isMoreThanRecommended,
+    })
+    const isIdenticalCatCombos =
+        identicalCatCombosResult.isSuccess &&
+        identicalCatCombosResult.data?.pager.total > 0
+
+    if (!isMoreThanRecommended && !isIdenticalCatCombos) {
+        return null
+    }
+
+    return (
+        <>
+            {isIdenticalCatCombos && (
+                <IdenticalCategoryComboWarning
+                    categoryCombos={
+                        identicalCatCombosResult.data.categoryCombos
+                    }
+                />
+            )}
+            {isMoreThanRecommended && (
+                <NoticeBox warning title={i18n.t('More than 4 Categories')}>
+                    {i18n.t(
+                        'A Category combination with more than 4 categories is not recommended.'
+                    )}
+                </NoticeBox>
+            )}
+        </>
+    )
+}
+
+const IdenticalCategoryComboWarning = ({
+    categoryCombos,
+}: {
+    categoryCombos: DisplayableModel[]
+}) => {
+    return (
+        <NoticeBox warning title={i18n.t('Identical Category Combination')}>
+            {i18n.t(
+                `One or more Category combinations with the same categories already exist in the system. 
+        It is strongly discouraged to have more than one Category combination with the same categories.`
+            )}
+            <br />
+            {i18n.t(
+                'The following Category combinations have identical categories:'
+            )}
+            <ul className={css.identicalCategoriesList}>
+                {categoryCombos.map((catCombo) => (
+                    <li key={catCombo.id}>
+                        <NavLink target="_blank" to={`../${catCombo.id}`}>
+                            {catCombo.displayName}
+                        </NavLink>
+                    </li>
+                ))}
+            </ul>
+        </NoticeBox>
+    )
+}

src/pages/categoryCombos/form/CategoryCombo.module.css

@@ -0,0 +1,21 @@
+.categoriesFieldWrapper {
+    display: flex;
+    flex-wrap: wrap;
+    gap: var(--spacers-dp8);
+}
+
+.categoriesNoticesWrapper {
+    display: flex;
+    flex-direction: column;
+    gap: var(--spacers-dp8);
+    max-width: 570px;
+}
+
+.identicalCategoriesList a {
+    color: var(--colors-blue600);
+}
+
+.identicalCategoriesList {
+    margin-inline: 0;
+    margin-block: var(--spacers-dp8);
+}

src/pages/categoryCombos/form/CategoryComboFormFields.tsx

@@ -13,6 +13,7 @@ import {
     CodeField,
 } from '../../../components'
 import { SECTIONS_MAP } from '../../../lib'
+import { CategoriesField } from './CategoriesField'
 
 const section = SECTIONS_MAP.categoryCombo
 
@@ -84,25 +85,7 @@ export const CategoryComboFormFields = () => {
                     )}
                 </StandardFormSectionDescription>
                 <StandardFormField>
-                    <StandardFormField>
-                        <ModelTransferField
-                            name="categories"
-                            query={{
-                                resource: 'categories',
-                                params: {
-                                    filter: ['name:ne:default'],
-                                },
-                            }}
-                            leftHeader={i18n.t('Available categories')}
-                            rightHeader={i18n.t('Selected categories')}
-                            filterPlaceholder={i18n.t(
-                                'Filter available categories'
-                            )}
-                            filterPlaceholderPicked={i18n.t(
-                                'Filter selected categories'
-                            )}
-                        />
-                    </StandardFormField>
+                    <CategoriesField />
                 </StandardFormField>
             </StandardFormSection>
         </>

src/pages/categoryCombos/form/categoryComboSchema.ts

@@ -4,8 +4,9 @@ import { getDefaults, modelFormSchemas } from '../../../lib'
 import { createFormValidate } from '../../../lib/form/validate'
 import { CategoryCombo } from './../../../types/generated/models'
 
-const { identifiable, withAttributeValues, referenceCollection } =
-    modelFormSchemas
+const { identifiable, withAttributeValues, modelReference } = modelFormSchemas
+
+const GENERATED_COC_LIMIT = 50000
 
 export const categoryComboSchema = identifiable
     .merge(withAttributeValues)
@@ -15,11 +16,33 @@ export const categoryComboSchema = identifiable
             .nativeEnum(CategoryCombo.dataDimensionType)
             .default(CategoryCombo.dataDimensionType.DISAGGREGATION),
         skipTotal: z.boolean().default(false),
-        categories: referenceCollection
-            .min(1, i18n.t('At least one category is required'))
+        categories: z
+            .array(
+                modelReference.extend({
+                    displayName: z.string(),
+                    categoryOptionsSize: z.number(),
+                })
+            )
+            .refine(
+                (categories) => {
+                    const generatedCocsCount = categories.reduce(
+                        (acc, category) => acc * category.categoryOptionsSize,
+                        1
+                    )
+                    return generatedCocsCount < GENERATED_COC_LIMIT
+                },
+                {
+                    message: i18n.t(
+                        'The number of generated category option combinations exceeds the limit of {{limit}}',
+                        { limit: GENERATED_COC_LIMIT }
+                    ),
+                }
+            )
             .default([]),
     })
 
 export const initialValues = getDefaults(categoryComboSchema)
 
+export type CategoryComboFormValues = typeof initialValues
+
 export const validate = createFormValidate(categoryComboSchema)

src/pages/categoryCombos/form/useIdenticalCategoryCombosQuery.tsx

@@ -0,0 +1,51 @@
+import { useQuery, QueryObserverOptions } from 'react-query'
+import { useBoundResourceQueryFn } from '../../../lib/query/useBoundQueryFn'
+import { PagedResponse } from '../../../types/generated'
+import { CategoryComboFormValues } from './categoryComboSchema'
+
+type CategoriesValue = Pick<CategoryComboFormValues, 'categories'>['categories']
+
+export type IdenticalCategoryCombosQueryResult = PagedResponse<
+    CategoriesValue[number],
+    'categoryCombos'
+>
+
+type UseIdenticalCategoryCombosQuery = {
+    categoryComboId?: string
+    selectedCategories: CategoriesValue
+} & Pick<
+    QueryObserverOptions<IdenticalCategoryCombosQueryResult>,
+    'enabled' | 'select' | 'cacheTime' | 'staleTime'
+>
+
+export const useIdenticalCategoryCombosQuery = ({
+    categoryComboId,
+    selectedCategories,
+    ...queryOptions
+}: UseIdenticalCategoryCombosQuery) => {
+    const queryFn = useBoundResourceQueryFn()
+    const notSameCatComboFilter = `id:ne:${categoryComboId}`
+    const idFilters = selectedCategories.map(
+        (category) => `categories.id:eq:${category.id}`
+    )
+    const lengthFilter = `categories:eq:${selectedCategories.length}`
+    const filters = [lengthFilter, ...idFilters]
+
+    if (categoryComboId) {
+        filters.push(notSameCatComboFilter)
+    }
+    const useIdenticalCategoryCombosQuery = {
+        resource: 'categoryCombos',
+        params: {
+            fields: ['id', 'displayName'],
+            filter: filters,
+        },
+    }
+
+    return useQuery({
+        staleTime: 60 * 1000,
+        ...queryOptions,
+        queryKey: [useIdenticalCategoryCombosQuery],
+        queryFn: queryFn<IdenticalCategoryCombosQueryResult>,
+    })
+}

src/types/query.ts

@@ -10,7 +10,7 @@ type QueryParams = {
     pageSize?: number
     page?: number
     fields?: string | string[]
-    filter: string | string[]
+    filter?: string | string[]
     [key: string]: unknown
 }