From 39b4cf62eac051cc4c7a1c74665e48b791a76e98 Mon Sep 17 00:00:00 2001
From: tdgao <mr.trumgao@gmail.com>
Date: Mon, 13 Jul 2026 14:23:58 -0700
Subject: [PATCH] feat: implement depends on search filter

---
 .../components/project/ProjectCombobox.vue    |  3 +-
 .../components/search/SearchFilterControl.vue | 61 ++++++++++++-
 .../components/search/SearchSidebarFilter.vue | 87 ++++++++++++++++++-
 .../composables/use-browse-search.ts          |  7 ++
 .../browse-tab/providers/browse-manager.ts    |  1 +
 .../src/layouts/shared/browse-tab/sidebar.vue |  2 +
 packages/ui/src/locales/en-US/index.json      | 12 +++
 packages/ui/src/utils/search.ts               | 29 ++++++-
 8 files changed, 192 insertions(+), 10 deletions(-)

diff --git a/packages/ui/src/components/project/ProjectCombobox.vue b/packages/ui/src/components/project/ProjectCombobox.vue
index dd616f6f80..15cc1a9b73 100644
--- a/packages/ui/src/components/project/ProjectCombobox.vue
+++ b/packages/ui/src/components/project/ProjectCombobox.vue
@@ -32,12 +32,13 @@ export type ProjectType =
 	| 'plugin'
 	| 'server'
 
-interface SearchHit {
+export interface SearchHit {
 	project_id: string
 	title: string
 	icon_url?: string
 	project_type: string
 	slug: string
+	author?: string
 }
 
 const props = withDefaults(
diff --git a/packages/ui/src/components/search/SearchFilterControl.vue b/packages/ui/src/components/search/SearchFilterControl.vue
index 72389cbf5f..755e787922 100644
--- a/packages/ui/src/components/search/SearchFilterControl.vue
+++ b/packages/ui/src/components/search/SearchFilterControl.vue
@@ -37,13 +37,16 @@
 
 <script setup lang="ts">
 import { BanIcon, LockIcon, XCircleIcon, XIcon } from '@modrinth/assets'
+import { useQuery } from '@tanstack/vue-query'
 import { computed, type ComputedRef } from 'vue'
 
 import { defineMessage, type MessageDescriptor, useVIntl } from '../../composables/i18n'
+import { injectModrinthClient } from '../../providers'
 import type { FilterOption, FilterType, FilterValue } from '../../utils/search'
 import TagItem from '../base/TagItem.vue'
 
 const { formatMessage } = useVIntl()
+const { labrinth } = injectModrinthClient()
 
 const selectedFilters = defineModel<FilterValue[]>('selectedFilters', { required: true })
 
@@ -58,6 +61,10 @@ const defaultProvidedMessage = defineMessage({
 	id: 'search.filter.locked.default',
 	defaultMessage: 'Filter locked',
 })
+const dependentProjectMessage = defineMessage({
+	id: 'search.filter.dependent_project',
+	defaultMessage: 'Depends on: {project}',
+})
 
 type Item = {
 	type: string
@@ -67,13 +74,39 @@ type Item = {
 	provided: boolean
 }
 
+const dependentProjectIds = computed(() =>
+	[
+		...new Set(
+			[...selectedFilters.value, ...props.providedFilters]
+				.filter((filter) => filter.type === 'compatible_dependency_project_ids')
+				.map((filter) => filter.option),
+		),
+	].sort(),
+)
+
+const { data: dependentProjects } = useQuery({
+	queryKey: computed(() => [
+		'search-filter-control',
+		'dependent-projects',
+		dependentProjectIds.value,
+	]),
+	queryFn: () => labrinth.projects_v2.getMultiple(dependentProjectIds.value),
+	enabled: computed(() => dependentProjectIds.value.length > 0),
+	placeholderData: [],
+	refetchOnWindowFocus: false,
+})
+
+const dependentProjectNames = computed(
+	() => new Map(dependentProjects.value?.map((project) => [project.id, project.title]) ?? []),
+)
+
 function filterMatches(type: FilterType, option: FilterOption, list: FilterValue[]) {
 	return list.some((provided) => provided.type === type.id && provided.option === option.id)
 }
 
 const items: ComputedRef<Item[]> = computed(() => {
-	return props.filters.flatMap((type) =>
-		type.options
+	return props.filters.flatMap((type) => {
+		const optionItems = type.options
 			.filter(
 				(option) =>
 					filterMatches(type, option, selectedFilters.value) ||
@@ -86,8 +119,30 @@ const items: ComputedRef<Item[]> = computed(() => {
 					?.negative,
 				provided: filterMatches(type, option, props.providedFilters),
 				formatted_name: option.formatted_name,
+			}))
+
+		if (type.id !== 'compatible_dependency_project_ids') {
+			return optionItems
+		}
+
+		const customValues = [...selectedFilters.value, ...props.providedFilters].filter(
+			(filter) => filter.type === type.id,
+		)
+		return [
+			...optionItems,
+			...customValues.map((filter) => ({
+				type: type.id,
+				option: filter.option,
+				negative: filter.negative,
+				provided: props.providedFilters.some(
+					(provided) => provided.type === type.id && provided.option === filter.option,
+				),
+				formatted_name: formatMessage(dependentProjectMessage, {
+					project: dependentProjectNames.value.get(filter.option) ?? filter.option,
+				}),
 			})),
-	)
+		]
+	})
 })
 
 const selectedItems = computed(() => items.value.filter((x) => !x.provided))
diff --git a/packages/ui/src/components/search/SearchSidebarFilter.vue b/packages/ui/src/components/search/SearchSidebarFilter.vue
index 99ca2b54ec..1e1b3b1863 100644
--- a/packages/ui/src/components/search/SearchSidebarFilter.vue
+++ b/packages/ui/src/components/search/SearchSidebarFilter.vue
@@ -71,6 +71,48 @@
 		</template>
 		<template v-else #default>
 			<slot name="prefix" />
+			<div
+				v-if="filterType.display === 'project'"
+				:class="innerPanelClass ? innerPanelClass : ''"
+				class="flex flex-col gap-3"
+			>
+				<ProjectCombobox
+					v-show="!selectedProjectId || refreshing"
+					ref="projectCombobox"
+					search-placeholder="Search for a project..."
+					:model-value="selectedProjectId"
+					:project-types="selectableProjectTypes"
+					@update:model-value="setSelectedProjectId"
+				/>
+				<template v-if="selectedProjectId && !refreshing">
+					<div class="flex items-center justify-between gap-3 px-2 text-secondary">
+						<span>{{ formatMessage(messages.dependentCount, { count: resultCount ?? 0 }) }}</span>
+						<button
+							class="border-none bg-transparent p-0 text-secondary cursor-pointer hover:text-contrast"
+							@click="setSelectedProjectId(undefined)"
+						>
+							{{ formatMessage(messages.clearFilter) }}
+						</button>
+					</div>
+					<div class="flex items-center gap-3 rounded-2xl bg-surface-1 p-3">
+						<img
+							v-if="selectedProject?.icon_url"
+							:src="selectedProject.icon_url"
+							:alt="selectedProject.title"
+							class="size-14 shrink-0 rounded-xl object-cover"
+						/>
+						<PackageIcon v-else class="size-14 shrink-0 text-secondary" />
+						<div class="min-w-0">
+							<div class="truncate text-base font-bold text-contrast">
+								{{ selectedProject?.title ?? selectedProjectId }}
+							</div>
+							<div v-if="selectedProject?.author" class="truncate text-sm text-secondary">
+								{{ selectedProject.author }}
+							</div>
+						</div>
+					</div>
+				</template>
+			</div>
 			<div
 				v-if="filterType.display === 'toggle'"
 				:class="innerPanelClass ? innerPanelClass : ''"
@@ -90,7 +132,7 @@
 					/>
 				</label>
 			</div>
-			<template v-if="filterType.display !== 'toggle'">
+			<template v-if="filterType.display !== 'toggle' && filterType.display !== 'project'">
 				<StyledInput
 					v-if="filterType.searchable"
 					:id="`search-${filterType.id}`"
@@ -206,7 +248,14 @@
 </template>
 
 <script setup lang="ts">
-import { BanIcon, DropdownIcon, LockOpenIcon, SearchIcon, UpdatedIcon } from '@modrinth/assets'
+import {
+	BanIcon,
+	DropdownIcon,
+	LockOpenIcon,
+	PackageIcon,
+	SearchIcon,
+	UpdatedIcon,
+} from '@modrinth/assets'
 import { computed, ref } from 'vue'
 
 import { defineMessages, useVIntl } from '../../composables/i18n'
@@ -215,6 +264,10 @@ import Accordion from '../base/Accordion.vue'
 import ButtonStyled from '../base/ButtonStyled.vue'
 import Toggle from '../base/Toggle.vue'
 import { Checkbox, ScrollablePanel, StyledInput } from '../index'
+import ProjectCombobox, {
+	type ProjectType as ProjectComboboxProjectType,
+	type SearchHit,
+} from '../project/ProjectCombobox.vue'
 import SearchFilterGroup from './SearchFilterGroup.vue'
 import SearchFilterOption from './SearchFilterOption.vue'
 
@@ -234,6 +287,8 @@ const props = defineProps<{
 	innerPanelClass?: string
 	openByDefault?: boolean
 	providedFilters: FilterValue[]
+	resultCount?: number
+	refreshing?: boolean
 }>()
 
 defineOptions({
@@ -244,6 +299,26 @@ const query = ref('')
 const showMore = ref(false)
 
 const accordion = ref<InstanceType<typeof Accordion> | null>()
+const projectCombobox = ref<{ selectedProject: SearchHit | null } | null>(null)
+const selectableProjectTypes: ProjectComboboxProjectType[] = [
+	'mod',
+	'modpack',
+	'resourcepack',
+	'shader',
+	'datapack',
+	'plugin',
+]
+const selectedProject = computed(() => projectCombobox.value?.selectedProject ?? null)
+const selectedProjectId = computed(
+	() => selectedFilters.value.find((filter) => filter.type === props.filterType.id)?.option,
+)
+
+function setSelectedProjectId(projectId: string | undefined) {
+	const otherFilters = selectedFilters.value.filter((filter) => filter.type !== props.filterType.id)
+	selectedFilters.value = projectId
+		? [...otherFilters, { type: props.filterType.id, option: projectId }]
+		: otherFilters
+}
 
 const selectedFilterOptions = computed(() =>
 	props.filterType.options.filter((option) =>
@@ -397,6 +472,14 @@ function clearFilters() {
 }
 
 const messages = defineMessages({
+	clearFilter: {
+		id: 'search.filter.clear',
+		defaultMessage: 'Clear',
+	},
+	dependentCount: {
+		id: 'search.filter.dependent_count',
+		defaultMessage: '{count, plural, one {# dependent} other {# dependents}}',
+	},
 	searchPlaceholder: {
 		id: 'search.filter.option.search.placeholder',
 		defaultMessage: 'Search...',
diff --git a/packages/ui/src/layouts/shared/browse-tab/composables/use-browse-search.ts b/packages/ui/src/layouts/shared/browse-tab/composables/use-browse-search.ts
index bc4861949e..12463e5a9e 100644
--- a/packages/ui/src/layouts/shared/browse-tab/composables/use-browse-search.ts
+++ b/packages/ui/src/layouts/shared/browse-tab/composables/use-browse-search.ts
@@ -48,6 +48,7 @@ export interface BrowseSearchState {
 	effectiveCurrentSortType: Ref<SortType>
 
 	loading: Ref<boolean>
+	refreshing: Ref<boolean>
 	projectHits: ShallowRef<BrowseSearchResponse['projectHits']>
 	serverHits: ShallowRef<BrowseSearchResponse['serverHits']>
 	totalHits: Ref<number>
@@ -172,6 +173,7 @@ export function useBrowseSearch(options: UseBrowseSearchOptions): BrowseSearchSt
 	])
 
 	const loading = ref(true)
+	const refreshing = ref(false)
 	const projectHits = shallowRef<BrowseSearchResponse['projectHits']>([])
 	const serverHits = shallowRef<BrowseSearchResponse['serverHits']>([])
 	const totalHits = ref(0)
@@ -205,6 +207,7 @@ export function useBrowseSearch(options: UseBrowseSearchOptions): BrowseSearchSt
 	)
 
 	watch(effectiveRequestParams, (newVal, oldVal) => {
+		refreshing.value = true
 		debug('effectiveRequestParams changed', {
 			from: oldVal?.substring(0, 80),
 			to: newVal?.substring(0, 80),
@@ -217,6 +220,7 @@ export function useBrowseSearch(options: UseBrowseSearchOptions): BrowseSearchSt
 
 	async function refreshSearch() {
 		const version = ++searchVersion
+		refreshing.value = true
 		debug('refreshSearch start', {
 			version,
 			projectType: options.projectType.value,
@@ -253,11 +257,13 @@ export function useBrowseSearch(options: UseBrowseSearchOptions): BrowseSearchSt
 
 			updateUrlParams()
 			loading.value = false
+			refreshing.value = false
 		} catch (err) {
 			debug('refreshSearch error', err)
 			console.error('Browse search error:', err)
 			if (version === searchVersion) {
 				loading.value = false
+				refreshing.value = false
 			}
 		}
 	}
@@ -323,6 +329,7 @@ export function useBrowseSearch(options: UseBrowseSearchOptions): BrowseSearchSt
 		effectiveSortTypes,
 		effectiveCurrentSortType,
 		loading,
+		refreshing,
 		projectHits,
 		serverHits,
 		totalHits,
diff --git a/packages/ui/src/layouts/shared/browse-tab/providers/browse-manager.ts b/packages/ui/src/layouts/shared/browse-tab/providers/browse-manager.ts
index 9d3133c91b..fe30899966 100644
--- a/packages/ui/src/layouts/shared/browse-tab/providers/browse-manager.ts
+++ b/packages/ui/src/layouts/shared/browse-tab/providers/browse-manager.ts
@@ -31,6 +31,7 @@ export interface BrowseManagerContext {
 	effectiveSortTypes: ComputedRef<readonly SortType[]>
 	effectiveCurrentSortType: Ref<SortType>
 	loading: Ref<boolean>
+	refreshing: Ref<boolean>
 	projectHits: ShallowRef<BrowseSearchResponse['projectHits']>
 	serverHits: ShallowRef<BrowseSearchResponse['serverHits']>
 	totalHits: Ref<number>
diff --git a/packages/ui/src/layouts/shared/browse-tab/sidebar.vue b/packages/ui/src/layouts/shared/browse-tab/sidebar.vue
index 29a78996ed..08537269e4 100644
--- a/packages/ui/src/layouts/shared/browse-tab/sidebar.vue
+++ b/packages/ui/src/layouts/shared/browse-tab/sidebar.vue
@@ -194,6 +194,8 @@ function getFilterOpenByDefault(filterId: string): boolean {
 				v-model:overridden-provided-filter-types="ctx.overriddenProvidedFilterTypes.value"
 				:provided-filters="ctx.providedFilters?.value ?? []"
 				:filter-type="filter"
+				:result-count="ctx.totalHits.value"
+				:refreshing="ctx.refreshing.value"
 				:class="filterClass"
 				:button-class="buttonClass"
 				:content-class="contentClass"
diff --git a/packages/ui/src/locales/en-US/index.json b/packages/ui/src/locales/en-US/index.json
index 23f276af3c..acb15399c2 100644
--- a/packages/ui/src/locales/en-US/index.json
+++ b/packages/ui/src/locales/en-US/index.json
@@ -3548,6 +3548,15 @@
   "s.bg": {
     "defaultMessage": "Background task running"
   },
+  "search.filter.clear": {
+    "defaultMessage": "Clear"
+  },
+  "search.filter.dependent_count": {
+    "defaultMessage": "{count, plural, one {# dependent} other {# dependents}}"
+  },
+  "search.filter.dependent_project": {
+    "defaultMessage": "Depends on: {project}"
+  },
   "search.filter.locked.default": {
     "defaultMessage": "Filter locked"
   },
@@ -3590,6 +3599,9 @@
   "search.filter_type.advanced.exclude_plugin": {
     "defaultMessage": "Exclude plugins"
   },
+  "search.filter_type.compatible_dependency_project_ids": {
+    "defaultMessage": "Depends on"
+  },
   "search.filter_type.environment": {
     "defaultMessage": "Environment"
   },
diff --git a/packages/ui/src/utils/search.ts b/packages/ui/src/utils/search.ts
index 5422a9b7fc..0651fe938e 100644
--- a/packages/ui/src/utils/search.ts
+++ b/packages/ui/src/utils/search.ts
@@ -43,10 +43,11 @@ export type FilterType = {
 	}[]
 	searchable: boolean
 	allows_custom_options?: 'and' | 'or'
+	custom_option_field?: string
 	ordering?: number
 } & (
 	| {
-			display: 'all' | 'scrollable' | 'none' | 'toggle'
+			display: 'all' | 'scrollable' | 'none' | 'project' | 'toggle'
 	  }
 	| {
 			display: 'expandable'
@@ -472,6 +473,24 @@ export function useSearch(
 				options: [],
 				allows_custom_options: 'and',
 			},
+			{
+				id: 'compatible_dependency_project_ids',
+				formatted_name: formatMessage(
+					defineMessage({
+						id: 'search.filter_type.compatible_dependency_project_ids',
+						defaultMessage: 'Depends on',
+					}),
+				),
+				supported_project_types: ALL_PROJECT_TYPES,
+				query_param: 'dep',
+				supports_negative_filter: false,
+				display: 'project',
+				searchable: false,
+				options: [],
+				allows_custom_options: 'and',
+				custom_option_field: 'compatible_dependency_project_ids',
+				ordering: -999,
+			},
 			{
 				id: 'advanced',
 				formatted_name: formatMessage(
@@ -533,7 +552,9 @@ export function useSearch(
 					formatted_name: filterValue.option,
 					icon: undefined,
 					method: type.allows_custom_options,
-					value: filterValue.option,
+					value: type.custom_option_field
+						? `${type.custom_option_field}:${filterValue.option}`
+						: filterValue.option,
 				}
 			} else if (!option) {
 				console.error(`Filter option ${filterValue.option} not found`)
@@ -771,8 +792,8 @@ export function useSearch(
 		currentFilters.value.forEach((filterValue) => {
 			const type = filters.value.find((type) => type.id === filterValue.type)
 			const option = type?.options.find((option) => option.id === filterValue.option)
-			if (type && option) {
-				const value = getOptionValue(option, filterValue.negative)
+			if (type && (option || type.allows_custom_options)) {
+				const value = option ? getOptionValue(option, filterValue.negative) : filterValue.option
 				if (items[type.query_param]) {
 					items[type.query_param].push(value)
 				} else {