import React, { useState, useRef, useEffect } from 'react';
import { User, LogOut, ChevronDown, Shield, Clock } from 'lucide-react';
import { useAuth } from '../contexts/AuthContext';
import UserProfilePanel from './UserProfilePanel';

// ============================================
// INLINE STYLES — Dark theme matching DESIGN_SYSTEM.md
// ============================================
const STYLES = {
    container: {
        position: 'relative',
    },
    menuButton: {
        display: 'flex',
        alignItems: 'center',
        gap: '0.5rem',
        padding: '0.5rem 0.75rem',
        borderRadius: '0.5rem',
        background: 'transparent',
        border: 'none',
        cursor: 'pointer',
        transition: 'background 0.2s',
    },
    menuButtonHover: {
        background: 'rgba(14, 165, 233, 0.1)',
    },
    avatar: {
        width: '2rem',
        height: '2rem',
        backgroundColor: '#0476D9',
        borderRadius: '9999px',
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'center',
    },
    avatarIcon: {
        color: '#FFFFFF',
    },
    userInfo: {
        textAlign: 'left',
    },
    username: {
        fontSize: '0.875rem',
        fontWeight: '500',
        color: '#F8FAFC',
        margin: 0,
        lineHeight: 1.25,
    },
    groupLabel: {
        fontSize: '0.75rem',
        color: '#E2E8F0',
        margin: 0,
        lineHeight: 1.25,
    },
    chevron: {
        color: '#E2E8F0',
        transition: 'transform 0.2s',
    },
    chevronOpen: {
        transform: 'rotate(180deg)',
    },
    // Dropdown panel
    dropdown: {
        position: 'absolute',
        right: 0,
        marginTop: '0.5rem',
        width: '16rem',
        background: 'linear-gradient(135deg, rgba(30, 41, 59, 0.95) 0%, rgba(51, 65, 85, 0.9) 50%, rgba(30, 41, 59, 0.95) 100%)',
        borderRadius: '0.5rem',
        boxShadow: '0 20px 60px rgba(0, 0, 0, 0.6), 0 10px 30px rgba(14, 165, 233, 0.1), inset 0 1px 0 rgba(255, 255, 255, 0.1)',
        border: '1.5px solid rgba(14, 165, 233, 0.3)',
        padding: '0.5rem 0',
        zIndex: 50,
    },
    // Dropdown header section
    dropdownHeader: {
        padding: '0.75rem 1rem',
        borderBottom: '1px solid rgba(14, 165, 233, 0.2)',
    },
    dropdownHeaderName: {
        fontSize: '0.875rem',
        fontWeight: '500',
        color: '#F8FAFC',
        margin: 0,
    },
    dropdownHeaderEmail: {
        fontSize: '0.875rem',
        color: '#94A3B8',
        margin: 0,
    },
    // Menu items
    menuItem: {
        width: '100%',
        padding: '0.5rem 1rem',
        textAlign: 'left',
        fontSize: '0.875rem',
        color: '#F8FAFC',
        background: 'transparent',
        border: 'none',
        cursor: 'pointer',
        display: 'flex',
        alignItems: 'center',
        gap: '0.75rem',
        transition: 'background 0.15s',
    },
    menuItemHover: {
        background: 'rgba(14, 165, 233, 0.1)',
    },
    // Sign out item
    signOutItem: {
        width: '100%',
        padding: '0.5rem 1rem',
        textAlign: 'left',
        fontSize: '0.875rem',
        color: '#F87171',
        background: 'transparent',
        border: 'none',
        cursor: 'pointer',
        display: 'flex',
        alignItems: 'center',
        gap: '0.75rem',
        transition: 'background 0.15s',
    },
    signOutItemHover: {
        background: 'rgba(239, 68, 68, 0.1)',
    },
};

/**
 * Returns inline style for the group badge in the dropdown header.
 * Retains the existing color-coding logic per group.
 */
function getGroupBadgeStyle(group) {
    const colors = {
        Admin: { bg: 'rgba(239, 68, 68, 0.2)', border: 'rgba(239, 68, 68, 0.5)', text: '#FCA5A5' },
        Standard_User: { bg: 'rgba(14, 165, 233, 0.2)', border: 'rgba(14, 165, 233, 0.5)', text: '#7DD3FC' },
        Leadership: { bg: 'rgba(168, 85, 247, 0.2)', border: 'rgba(168, 85, 247, 0.5)', text: '#D8B4FE' },
        Read_Only: { bg: 'rgba(148, 163, 184, 0.2)', border: 'rgba(148, 163, 184, 0.5)', text: '#CBD5E1' },
    };
    const c = colors[group] || colors.Read_Only;
    return {
        display: 'inline-block',
        marginTop: '0.5rem',
        padding: '0.125rem 0.5rem',
        borderRadius: '0.25rem',
        fontSize: '0.75rem',
        fontWeight: '500',
        background: c.bg,
        border: `1px solid ${c.border}`,
        color: c.text,
    };
}

export default function UserMenu({ onManageUsers, onAuditLog }) {
    const { user, logout, isAdmin } = useAuth();
    const [isOpen, setIsOpen] = useState(false);
    const [buttonHovered, setButtonHovered] = useState(false);
    const [hoveredItem, setHoveredItem] = useState(null);
    const [showProfile, setShowProfile] = useState(false);
    const menuRef = useRef(null);

    // Close menu when clicking outside
    useEffect(() => {
        function handleClickOutside(event) {
            if (menuRef.current && !menuRef.current.contains(event.target)) {
                setIsOpen(false);
            }
        }

        document.addEventListener('mousedown', handleClickOutside);
        return () => document.removeEventListener('mousedown', handleClickOutside);
    }, []);

    const formatGroupName = (group) => {
        if (!group) return '';
        return group.replace(/_/g, ' ');
    };

    const handleLogout = async () => {
        setIsOpen(false);
        await logout();
    };

    const handleProfile = () => {
        setIsOpen(false);
        setShowProfile(true);
    };

    const handleManageUsers = () => {
        setIsOpen(false);
        if (onManageUsers) {
            onManageUsers();
        }
    };

    const handleAuditLog = () => {
        setIsOpen(false);
        if (onAuditLog) {
            onAuditLog();
        }
    };

    if (!user) return null;

    return (
        <div style={STYLES.container} ref={menuRef}>
            <button
                onClick={() => setIsOpen(!isOpen)}
                onMouseEnter={() => setButtonHovered(true)}
                onMouseLeave={() => setButtonHovered(false)}
                style={{
                    ...STYLES.menuButton,
                    ...(buttonHovered ? STYLES.menuButtonHover : {}),
                }}
            >
                <div style={STYLES.avatar}>
                    <User size={16} style={STYLES.avatarIcon} />
                </div>
                <div style={STYLES.userInfo} className="hidden sm:block">
                    <p style={STYLES.username}>{user.username}</p>
                    <p style={STYLES.groupLabel}>{formatGroupName(user.group)}</p>
                </div>
                <ChevronDown
                    size={16}
                    style={{
                        ...STYLES.chevron,
                        ...(isOpen ? STYLES.chevronOpen : {}),
                    }}
                />
            </button>

            {isOpen && (
                <div style={STYLES.dropdown}>
                    <div style={STYLES.dropdownHeader}>
                        <p style={STYLES.dropdownHeaderName}>{user.username}</p>
                        <p style={STYLES.dropdownHeaderEmail}>{user.email}</p>
                        <span style={getGroupBadgeStyle(user.group)}>
                            {formatGroupName(user.group)}
                        </span>
                    </div>

                    <button
                        onClick={handleProfile}
                        onMouseEnter={() => setHoveredItem('profile')}
                        onMouseLeave={() => setHoveredItem(null)}
                        style={{
                            ...STYLES.menuItem,
                            ...(hoveredItem === 'profile' ? STYLES.menuItemHover : {}),
                        }}
                    >
                        <User size={16} />
                        My Profile
                    </button>

                    {isAdmin() && (
                        <>
                            <button
                                onClick={handleManageUsers}
                                onMouseEnter={() => setHoveredItem('manage')}
                                onMouseLeave={() => setHoveredItem(null)}
                                style={{
                                    ...STYLES.menuItem,
                                    ...(hoveredItem === 'manage' ? STYLES.menuItemHover : {}),
                                }}
                            >
                                <Shield size={16} />
                                Manage Users
                            </button>
                            <button
                                onClick={handleAuditLog}
                                onMouseEnter={() => setHoveredItem('audit')}
                                onMouseLeave={() => setHoveredItem(null)}
                                style={{
                                    ...STYLES.menuItem,
                                    ...(hoveredItem === 'audit' ? STYLES.menuItemHover : {}),
                                }}
                            >
                                <Clock size={16} />
                                Audit Log
                            </button>
                        </>
                    )}

                    <button
                        onClick={handleLogout}
                        onMouseEnter={() => setHoveredItem('signout')}
                        onMouseLeave={() => setHoveredItem(null)}
                        style={{
                            ...STYLES.signOutItem,
                            ...(hoveredItem === 'signout' ? STYLES.signOutItemHover : {}),
                        }}
                    >
                        <LogOut size={16} />
                        Sign Out
                    </button>
                </div>
            )}
            <UserProfilePanel isOpen={showProfile} onClose={() => setShowProfile(false)} />
        </div>
    );
}