Add multi-tenancy with Teams feature

frontend/src/components/UserAutocomplete.tsx

@@ -0,0 +1,171 @@
+import { useState, useEffect, useRef, useCallback } from 'react';
+import { searchUsers, UserSearchResult } from '../api';
+import './UserAutocomplete.css';
+
+interface UserAutocompleteProps {
+  value: string;
+  onChange: (username: string) => void;
+  placeholder?: string;
+  disabled?: boolean;
+  autoFocus?: boolean;
+}
+
+export function UserAutocomplete({
+  value,
+  onChange,
+  placeholder = 'Search users...',
+  disabled = false,
+  autoFocus = false,
+}: UserAutocompleteProps) {
+  const [query, setQuery] = useState(value);
+  const [results, setResults] = useState<UserSearchResult[]>([]);
+  const [loading, setLoading] = useState(false);
+  const [isOpen, setIsOpen] = useState(false);
+  const [selectedIndex, setSelectedIndex] = useState(-1);
+  const containerRef = useRef<HTMLDivElement>(null);
+  const inputRef = useRef<HTMLInputElement>(null);
+  const debounceRef = useRef<ReturnType<typeof setTimeout>>();
+
+  // Search for users with debounce
+  const doSearch = useCallback(async (searchQuery: string) => {
+    if (searchQuery.length < 1) {
+      setResults([]);
+      setIsOpen(false);
+      return;
+    }
+
+    setLoading(true);
+    try {
+      const users = await searchUsers(searchQuery);
+      setResults(users);
+      setIsOpen(users.length > 0);
+      setSelectedIndex(-1);
+    } catch {
+      setResults([]);
+      setIsOpen(false);
+    } finally {
+      setLoading(false);
+    }
+  }, []);
+
+  // Handle input change with debounce
+  const handleInputChange = (e: React.ChangeEvent<HTMLInputElement>) => {
+    const newValue = e.target.value;
+    setQuery(newValue);
+    onChange(newValue); // Update parent immediately for form validation
+
+    // Debounce the search
+    if (debounceRef.current) {
+      clearTimeout(debounceRef.current);
+    }
+    debounceRef.current = setTimeout(() => {
+      doSearch(newValue);
+    }, 200);
+  };
+
+  // Handle selecting a user
+  const handleSelect = (user: UserSearchResult) => {
+    setQuery(user.username);
+    onChange(user.username);
+    setIsOpen(false);
+    setResults([]);
+    inputRef.current?.focus();
+  };
+
+  // Handle keyboard navigation
+  const handleKeyDown = (e: React.KeyboardEvent) => {
+    if (!isOpen) return;
+
+    switch (e.key) {
+      case 'ArrowDown':
+        e.preventDefault();
+        setSelectedIndex(prev => (prev < results.length - 1 ? prev + 1 : prev));
+        break;
+      case 'ArrowUp':
+        e.preventDefault();
+        setSelectedIndex(prev => (prev > 0 ? prev - 1 : -1));
+        break;
+      case 'Enter':
+        e.preventDefault();
+        if (selectedIndex >= 0 && results[selectedIndex]) {
+          handleSelect(results[selectedIndex]);
+        }
+        break;
+      case 'Escape':
+        setIsOpen(false);
+        break;
+    }
+  };
+
+  // Close dropdown when clicking outside
+  useEffect(() => {
+    const handleClickOutside = (e: MouseEvent) => {
+      if (containerRef.current && !containerRef.current.contains(e.target as Node)) {
+        setIsOpen(false);
+      }
+    };
+
+    document.addEventListener('mousedown', handleClickOutside);
+    return () => document.removeEventListener('mousedown', handleClickOutside);
+  }, []);
+
+  // Sync external value changes
+  useEffect(() => {
+    setQuery(value);
+  }, [value]);
+
+  // Cleanup debounce on unmount
+  useEffect(() => {
+    return () => {
+      if (debounceRef.current) {
+        clearTimeout(debounceRef.current);
+      }
+    };
+  }, []);
+
+  return (
+    <div className="user-autocomplete" ref={containerRef}>
+      <div className="user-autocomplete__input-wrapper">
+        <input
+          ref={inputRef}
+          type="text"
+          value={query}
+          onChange={handleInputChange}
+          onKeyDown={handleKeyDown}
+          onFocus={() => query.length >= 1 && results.length > 0 && setIsOpen(true)}
+          placeholder={placeholder}
+          disabled={disabled}
+          autoFocus={autoFocus}
+          autoComplete="off"
+          className="user-autocomplete__input"
+        />
+        {loading && (
+          <div className="user-autocomplete__spinner" />
+        )}
+      </div>
+
+      {isOpen && results.length > 0 && (
+        <ul className="user-autocomplete__dropdown">
+          {results.map((user, index) => (
+            <li
+              key={user.id}
+              className={`user-autocomplete__option ${index === selectedIndex ? 'selected' : ''}`}
+              onClick={() => handleSelect(user)}
+              onMouseEnter={() => setSelectedIndex(index)}
+            >
+              <div className="user-autocomplete__avatar">
+                {user.username.charAt(0).toUpperCase()}
+              </div>
+              <div className="user-autocomplete__user-info">
+                <span className="user-autocomplete__username">{user.username}</span>
+                {user.is_admin && (
+                  <span className="user-autocomplete__admin-badge">Admin</span>
+                )}
+              </div>
+            </li>
+          ))}
+        </ul>
+      )}
+    </div>
+  );
+}