From 0804256b6ddbbe546c5c55c2b2cffea387e0e3eb Mon Sep 17 00:00:00 2001
From: araemer <anika@raemer.net>
Date: Sat, 28 Feb 2026 07:59:33 +0100
Subject: [PATCH] Add filter component for tags to recipe list toolbar

---
 .../src/components/basics/FilterDropDown.tsx  | 225 ++++++++++++++++++
 .../src/components/basics/SearchField.tsx     |  31 +--
 .../src/components/basics/StickyHeader.tsx    |   2 +-
 .../src/components/recipes/RecipeListPage.tsx |  35 ++-
 .../components/recipes/RecipeListToolbar.tsx  |  64 +++--
 5 files changed, 306 insertions(+), 51 deletions(-)
 create mode 100644 frontend/src/components/basics/FilterDropDown.tsx

diff --git a/frontend/src/components/basics/FilterDropDown.tsx b/frontend/src/components/basics/FilterDropDown.tsx
new file mode 100644
index 0000000..ca62e18
--- /dev/null
+++ b/frontend/src/components/basics/FilterDropDown.tsx
@@ -0,0 +1,225 @@
+import {useEffect, useRef, useState} from "react"
+import {Check, ChevronDown, Search, X} from "lucide-react"
+import {defaultIconSize} from "./SvgIcon"
+import clsx from "clsx"
+
+/**
+ * A single selectable option in the dropdown.
+ * Generic so the component can be reused for tags, categories, users, etc.
+ */
+export type FilterOption = {
+    id: string
+    label: string
+}
+
+/**
+ * Self-contained model for a FilterDropdown instance.
+ * Pass this as a single prop to avoid threading multiple filter-related
+ * props through intermediate components.
+ */
+export type FilterDropdownModel = {
+    /** Label shown on the trigger button when nothing is selected, e.g. "Tags" */
+    placeholder: string
+    /** Full list of available options */
+    options: FilterOption[]
+    /** Currently selected option IDs */
+    selectedIds: string[]
+    /** Called whenever the selection changes */
+    onSelectionChanged: (selectedIds: string[]) => void
+}
+
+type FilterDropdownProps = {
+    model: FilterDropdownModel
+    /** Optional additional Tailwind classes for the root element */
+    className?: string
+}
+
+/**
+ * A generic multi-select filter dropdown styled similarly to Jira's label filter.
+ *
+ * - Closed state: shows placeholder, single selected label, or "Multiple (n)"
+ * - Open state: search field + scrollable checkbox list + deselect-all footer
+ * - Closes on outside click or Escape
+ */
+export default function FilterDropdown({model, className = ""}: FilterDropdownProps) {
+    const {placeholder, options, selectedIds, onSelectionChanged} = model
+
+    const [isOpen, setIsOpen] = useState(false)
+    const [filterText, setFilterText] = useState("")
+    const containerRef = useRef<HTMLDivElement>(null)
+    const searchRef = useRef<HTMLInputElement>(null)
+
+    // Close on outside click
+    useEffect(() => {
+        const handleClickOutside = (e: MouseEvent) => {
+            if (containerRef.current && !containerRef.current.contains(e.target as Node)) {
+                closeDropdown()
+            }
+        }
+        document.addEventListener("mousedown", handleClickOutside)
+        return () => document.removeEventListener("mousedown", handleClickOutside)
+    }, [])
+
+    // Focus search input when opening
+    useEffect(() => {
+        if (isOpen) {
+            setTimeout(() => searchRef.current?.focus(), 0)
+        }
+    }, [isOpen])
+
+    const closeDropdown = () => {
+        setIsOpen(false)
+        setFilterText("")
+    }
+
+    const toggleOpen = () => {
+        if (isOpen) {
+            closeDropdown()
+        } else {
+            setIsOpen(true)
+        }
+    }
+
+    const toggleOption = (id: string) => {
+        if (selectedIds.includes(id)) {
+            onSelectionChanged(selectedIds.filter(sid => sid !== id))
+        } else {
+            onSelectionChanged([...selectedIds, id])
+        }
+    }
+
+    const deselectAll = () => onSelectionChanged([])
+
+    // Filter options by search text
+    const visibleOptions = options.filter(opt =>
+        opt.label.toLowerCase().includes(filterText.toLowerCase())
+    )
+
+    // Derive button label
+    const buttonLabel = (() => {
+        if (selectedIds.length === 0) return placeholder
+        if (selectedIds.length === 1) {
+            const match = options.find(o => o.id === selectedIds[0])
+            return match?.label ?? placeholder
+        }
+        return `Multiple (${selectedIds.length})`
+    })()
+
+    const hasSelection = selectedIds.length > 0
+
+    return (
+        <div ref={containerRef} className={clsx("relative", className)}>
+            {/* Trigger button */}
+            <button
+                type="button"
+                onClick={toggleOpen}
+                className={clsx(
+                    "flex items-center justify-between gap-2 w-full",
+                    "border border-gray-300 rounded px-3 py-2 bg-white",
+                    "text-sm text-left leading-tight",
+                    "hover:border-gray-400 focus:outline-none focus:ring-2 focus:ring-blue-300 transition-colors",
+                    hasSelection && "border-blue-400 bg-blue-50 text-blue-800",
+                    isOpen && "border-blue-400 ring-2 ring-blue-300"
+                )}
+            >
+                <span className={clsx("truncate", !hasSelection && "text-gray-400")}>
+                    {buttonLabel}
+                </span>
+                <ChevronDown
+                    size={defaultIconSize}
+                    className={clsx(
+                        "flex-shrink-0 text-gray-400 transition-transform duration-150",
+                        isOpen && "rotate-180"
+                    )}
+                />
+            </button>
+
+            {/* Dropdown panel */}
+            {isOpen && (
+                <div className={clsx(
+                    "absolute z-50 mt-1 w-full min-w-[220px]",
+                    "bg-white border border-gray-200 rounded shadow-lg",
+                    "flex flex-col"
+                )}>
+                    {/* Search field inside dropdown */}
+                    <div className="relative p-2 border-b border-gray-100">
+                        <input
+                            ref={searchRef}
+                            type="text"
+                            placeholder="Search…"
+                            value={filterText}
+                            onChange={e => setFilterText(e.target.value)}
+                            onKeyDown={e => e.key === "Escape" && closeDropdown()}
+                            className="w-full pl-8 pr-8 py-1.5 text-sm border border-gray-200 rounded focus:outline-none focus:ring-2 focus:ring-blue-300"
+                        />
+                        <Search
+                            size={14}
+                            className="absolute left-4 top-1/2 -translate-y-1/2 text-gray-400 pointer-events-none"
+                        />
+                        {filterText && (
+                            <button
+                                type="button"
+                                onClick={() => setFilterText("")}
+                                className="absolute right-4 top-1/2 -translate-y-1/2 text-gray-400 hover:text-gray-600"
+                            >
+                                <X size={14}/>
+                            </button>
+                        )}
+                    </div>
+
+                    {/* Options list */}
+                    <ul className="overflow-y-auto max-h-52">
+                        {visibleOptions.length === 0 ? (
+                            <li className="px-3 py-2 text-sm text-gray-400 italic">
+                                No results
+                            </li>
+                        ) : (
+                            visibleOptions.map(option => {
+                                const isSelected = selectedIds.includes(option.id)
+                                return (
+                                    <li key={option.id}>
+                                        <button
+                                            type="button"
+                                            onClick={() => toggleOption(option.id)}
+                                            className={clsx(
+                                                "flex items-center gap-2 w-full px-3 py-2 text-sm text-left",
+                                                "hover:bg-blue-50 transition-colors",
+                                                isSelected && "bg-blue-50 text-blue-800"
+                                            )}
+                                        >
+                                            <span className={clsx(
+                                                "flex-shrink-0 w-4 h-4 rounded border flex items-center justify-center transition-colors",
+                                                isSelected
+                                                    ? "bg-blue-500 border-blue-500"
+                                                    : "bg-white border-gray-300"
+                                            )}>
+                                                {isSelected && (
+                                                    <Check size={11} className="text-white" strokeWidth={3}/>
+                                                )}
+                                            </span>
+                                            <span className="truncate">{option.label}</span>
+                                        </button>
+                                    </li>
+                                )
+                            })
+                        )}
+                    </ul>
+
+                    {/* Footer: deselect all */}
+                    {hasSelection && (
+                        <div className="border-t border-gray-100 p-2">
+                            <button
+                                type="button"
+                                onClick={deselectAll}
+                                className="flex items-center gap-1.5 text-xs text-gray-500 hover:text-red-500 transition-colors w-full px-1 py-0.5"
+                            >
+                                <X size={12}/>
+                                Deselect all
+                            </button>
+                        </div>
+                    )}
+                </div>
+            )}
+        </div>
+    )
+}
\ No newline at end of file
diff --git a/frontend/src/components/basics/SearchField.tsx b/frontend/src/components/basics/SearchField.tsx
index f66e54b..03f4628 100644
--- a/frontend/src/components/basics/SearchField.tsx
+++ b/frontend/src/components/basics/SearchField.tsx
@@ -19,7 +19,6 @@ export default function SearchField({onSearchStringChanged, className = ""}: Sea
     const [currentSearchString, setCurrentSearchString] = useState<string>("")
 
     const changeSearchString = (newSearchString: string) => {
-        console.log(newSearchString);
         setCurrentSearchString(newSearchString);
         onSearchStringChanged(newSearchString)
     }
@@ -27,41 +26,29 @@ export default function SearchField({onSearchStringChanged, className = ""}: Sea
     const iconStyle: string = "text-gray-400 hover:text-gray-500";
 
     return (
-        <div className={clsx(
-            "relative",
-            className)}>
-            {/* Input of searchfield
-            Defines border and behavior. Requires extra padding at both sides to
-            accommodate the icons
-         */}
+        <div className={clsx("relative", className)}>
             <input
-                className="pl-10 pr-10"
+                className="w-full pl-10 pr-10 py-2 text-sm border border-gray-300 rounded bg-white leading-tight focus:outline-none focus:ring-2 focus:ring-blue-300 focus:border-blue-400 transition-colors"
                 type="text"
-                placeholder="Search"
+                placeholder="Suche"
                 value={currentSearchString}
                 onChange={e => changeSearchString(e.target.value)}
             />
-            {/* Right icon: X
-            Clears search string on click
-          */}
+            {/* Right icon: X — clears search string on click */}
             <button
                 className={clsx(
-                    "absolute right-0 inset-y-0 flex items-center -ml-1 mr-3",
+                    "absolute right-0 inset-y-0 flex items-center mr-3",
                     iconStyle)}
                 onClick={() => changeSearchString("")}
             >
-                <X
-                    size={defaultIconSize}
-                />
+                <X size={defaultIconSize}/>
             </button>
-            {/* Left icon: Looking glass */}
+            {/* Left icon: looking glass */}
             <div className={clsx(
                 "absolute left-0 inset-y-0 flex items-center ml-3",
                 iconStyle)}>
-                <Search
-                    size={defaultIconSize}
-                />
+                <Search size={defaultIconSize}/>
             </div>
         </div>
     )
-}
+}
\ No newline at end of file
diff --git a/frontend/src/components/basics/StickyHeader.tsx b/frontend/src/components/basics/StickyHeader.tsx
index 39d6536..f73f63d 100644
--- a/frontend/src/components/basics/StickyHeader.tsx
+++ b/frontend/src/components/basics/StickyHeader.tsx
@@ -26,7 +26,7 @@ export default function StickyHeader({children, className = ""}: StickyHeaderPro
     return (
         <div
             className={clsx(
-                "sticky top-0 left-0 right-0 bg-gray-100 pb-6 border-b-2 border-gray-300 z-10",
+                "sticky top-0 left-0 right-0 bg-gray-100 pb-4 border-b-2 border-gray-300 z-10",
                 className
             )}
         >
diff --git a/frontend/src/components/recipes/RecipeListPage.tsx b/frontend/src/components/recipes/RecipeListPage.tsx
index dc4359c..166969b 100644
--- a/frontend/src/components/recipes/RecipeListPage.tsx
+++ b/frontend/src/components/recipes/RecipeListPage.tsx
@@ -2,6 +2,8 @@ import {useEffect, useState} from "react"
 import RecipeListItem from "./RecipeListItem"
 import type {CompactRecipeDto} from "../../api/dtos/CompactRecipeDto.ts"
 import {fetchRecipeList} from "../../api/endpoints/CompactRecipeRestResource.ts"
+import {fetchAllTags} from "../../api/endpoints/TagRestResource.ts"
+import type {FilterDropdownModel, FilterOption} from "../basics/FilterDropDown.tsx"
 import {useNavigate} from "react-router-dom"
 import {getRecipeAddUrl, getRecipeDetailUrl, getRecipeListUrl} from "../../routes"
 import RecipeListToolbar from "./RecipeListToolbar"
@@ -20,14 +22,27 @@ export default function RecipeListPage() {
     const navigate = useNavigate()
     const [recipeList, setRecipeList] = useState<CompactRecipeDto[] | null>(null)
     const [searchString, setSearchString] = useState<string>("")
-    const [tagIdList, setTagIdList] = useState<string[]>([])
+    const [tagOptions, setTagOptions] = useState<FilterOption[]>([])
+    const [selectedTagIds, setSelectedTagIds] = useState<string[]>([])
 
-    // Reload list whenever search string or tag filter changes, debounced to
-    // avoid firing on every keystroke
+    // Load available tags once on mount to populate the filter dropdown
+    useEffect(() => {
+        fetchAllTags()
+            .then(dtos => setTagOptions(
+                dtos
+                    // ensure that all tags indeed have ids as this is required by the FilterOption
+                    .filter((dto): dto is typeof dto & { id: string } => dto.id !== undefined)
+                    // map to filter option
+                    .map(dto => ({id: dto.id, label: dto.description}))
+            ))
+            .catch(console.error)
+    }, [])
+
+    // Reload recipe list whenever search string or tag selection changes, debounced
     useEffect(() => {
         const timeout = setTimeout(async () => {
             try {
-                const data = await fetchRecipeList(searchString, tagIdList)
+                const data = await fetchRecipeList(searchString, selectedTagIds)
                 setRecipeList(data)
             } catch (err) {
                 console.error(err)
@@ -35,10 +50,13 @@ export default function RecipeListPage() {
         }, SEARCH_DEBOUNCE_MS)
 
         return () => clearTimeout(timeout)
-    }, [searchString, tagIdList])
+    }, [searchString, selectedTagIds])
 
-    const handleAdd = () => {
-        navigate(getRecipeAddUrl())
+    const tagFilterModel: FilterDropdownModel = {
+        placeholder: "Kategorie",
+        options: tagOptions,
+        selectedIds: selectedTagIds,
+        onSelectionChanged: setSelectedTagIds,
     }
 
     if (!recipeList) {
@@ -54,9 +72,10 @@ export default function RecipeListPage() {
                 <StickyHeader>
                     <h1>Recipes</h1>
                     <RecipeListToolbar
-                        onAddClicked={handleAdd}
+                        onAddClicked={() => navigate(getRecipeAddUrl())}
                         onSearchStringChanged={setSearchString}
                         numberOfRecipes={recipeList.length}
+                        tagFilterModel={tagFilterModel}
                     />
                 </StickyHeader>
                 {/* Content - List of recipe cards */}
diff --git a/frontend/src/components/recipes/RecipeListToolbar.tsx b/frontend/src/components/recipes/RecipeListToolbar.tsx
index 2622b0b..57d382d 100644
--- a/frontend/src/components/recipes/RecipeListToolbar.tsx
+++ b/frontend/src/components/recipes/RecipeListToolbar.tsx
@@ -1,35 +1,59 @@
-import { ButtonType } from "../basics/BasicButtonDefinitions"
+import {ButtonType} from "../basics/BasicButtonDefinitions"
 import Button from "../basics/Button"
 import SearchField from "../basics/SearchField"
+import FilterDropdown, {type FilterDropdownModel} from "../basics/FilterDropDown"
 
 /**
- * Toolbar for RecipeListPage containing searchfield, add recipe button and number of recipes
+ * Toolbar for RecipeListPage containing tag filter, search field, add button and recipe count.
+ *
+ * Single-line (wide): [12 Recipes]           [Tags ˅] [Search        ×] [Add recipe]
+ * Two-line (narrow):  [12 Recipes]                    [Search        ×] [Add recipe]
+ *                                                      [Tags ˅ — same width as above]
  */
-type RecepeListToolbarProps = { 
-    onSearchStringChanged: (searchString : string) => void
+type RecipeListToolbarProps = {
+    onSearchStringChanged: (searchString: string) => void
     onAddClicked: () => void
-    numberOfRecipes : number
+    numberOfRecipes: number
+    tagFilterModel: FilterDropdownModel
 }
 
-export default function RecipeListToolbar({onSearchStringChanged, onAddClicked, numberOfRecipes} : RecepeListToolbarProps){
+export default function RecipeListToolbar({
+                                              onSearchStringChanged,
+                                              onAddClicked,
+                                              numberOfRecipes,
+                                              tagFilterModel,
+                                          }: RecipeListToolbarProps) {
     return (
-        <div className="flex flex-wrap items-center gap-2 w-full">
-            {/* Label: left-aligned on medium+ screens, full-width on small screens */}
-            <div className="order-2 md:order-1 w-full md:w-auto md:flex-1">
-                <label className="label">{numberOfRecipes} Recipes</label>
+        <div className="flex items-center gap-2 w-full">
+
+            {/* Recipe count — left side, grows to push right-side group to the edge */}
+            <div className="flex-1">
+                <label className="label">{numberOfRecipes} Rezepte</label>
             </div>
 
-            {/* Search + Add button container: right-aligned on medium+ screens */}
-            <div className="order-1 md:order-2 flex flex-1 md:flex-none justify-end gap-2 min-w-[160px]">
-                <div className="flex-1 md:flex-none md:max-w-[500px]">
-                <SearchField onSearchStringChanged={onSearchStringChanged} />
+            {/* Right-side group: wraps internally so Tags falls under Search+Button
+                and inherits exactly the same width */}
+            <div className="flex flex-wrap justify-end gap-2">
+
+                {/* Tags — order-2 so it wraps to row 2 below Search+Button */}
+                <div className="order-2 w-full md:order-1 md:w-auto md:min-w-[100px] md:max-w-[200px]">
+                    <FilterDropdown model={tagFilterModel} className="w-full"/>
                 </div>
-                <Button
-                    buttonType = {ButtonType.PrimaryButton}
-                    className="flex-shrink-0"
-                    onClick={onAddClicked}
-                    text = "Add recipe"
-                />
+
+                {/* Search + Button — order-1 so they stay on row 1 when wrapping */}
+                <div className="order-1 md:order-2 flex gap-2 flex-shrink-0">
+                    <SearchField
+                        onSearchStringChanged={onSearchStringChanged}
+                        className="w-[260px]"
+                    />
+                    <Button
+                        buttonType={ButtonType.PrimaryButton}
+                        className="flex-shrink-0"
+                        onClick={onAddClicked}
+                        text="Neues Rezept"
+                    />
+                </div>
+
             </div>
         </div>
     )