# routes/admin_routes.py - Admin Dashboard Routes

from flask import Blueprint, request, jsonify, session, send_from_directory
from db import get_db
from auth import admin_required

admin_bp = Blueprint('admin', __name__)


@admin_bp.route('/admin')
@admin_required
def admin_page():
    """Serve admin dashboard page."""
    return send_from_directory('templates', 'admin.html')


@admin_bp.route('/api/admin/users', methods=['GET'])
@admin_required
def list_users():
    """List all users."""
    db = get_db()
    cursor = db.cursor()
    
    cursor.execute('''
        SELECT id, username, role, is_active, created_at, last_login
        FROM users ORDER BY created_at DESC
    ''')
    
    users = []
    for row in cursor.fetchall():
        users.append({
            'id': row['id'],
            'username': row['username'],
            'role': row['role'],
            'is_active': bool(row['is_active']),
            'created_at': row['created_at'],
            'last_login': row['last_login']
        })
    
    return jsonify({'users': users})


@admin_bp.route('/api/admin/users', methods=['POST'])
@admin_required
def create_user():
    """Create a new user."""
    data = request.json
    username = data.get('username', '').strip()
    password = data.get('password', '')
    role = data.get('role', 'user')
    
    if not username or not password:
        return jsonify({'error': 'Username and password are required'}), 400
    
    if len(username) < 3:
        return jsonify({'error': 'Username must be at least 3 characters'}), 400
    
    if len(password) < 4:
        return jsonify({'error': 'Password must be at least 4 characters'}), 400
    
    if role not in ('user', 'admin'):
        return jsonify({'error': 'Role must be "user" or "admin"'}), 400
    
    db = get_db()
    cursor = db.cursor()
    
    try:
        cursor.execute('''
            INSERT INTO users (username, password, role, is_active)
            VALUES (?, ?, ?, 1)
        ''', (username, password, role))
        db.commit()
        
        print(f"✅ New user created: {username} (role: {role})")
        
        return jsonify({
            'success': True,
            'user_id': cursor.lastrowid,
            'message': f'User "{username}" created successfully'
        })
    except Exception as e:
        if 'UNIQUE constraint' in str(e):
            return jsonify({'error': f'Username "{username}" already exists'}), 400
        return jsonify({'error': str(e)}), 500


@admin_bp.route('/api/admin/users/<int:user_id>', methods=['PUT'])
@admin_required
def update_user(user_id):
    """Update a user."""
    data = request.json
    
    db = get_db()
    cursor = db.cursor()
    
    cursor.execute('SELECT id, username FROM users WHERE id = ?', (user_id,))
    user = cursor.fetchone()
    
    if not user:
        return jsonify({'error': 'User not found'}), 404
    
    # Build update query dynamically
    updates = []
    params = []
    
    if 'username' in data:
        username = data['username'].strip()
        if len(username) < 3:
            return jsonify({'error': 'Username must be at least 3 characters'}), 400
        updates.append('username = ?')
        params.append(username)
    
    if 'password' in data and data['password']:
        password = data['password']
        if len(password) < 4:
            return jsonify({'error': 'Password must be at least 4 characters'}), 400
        updates.append('password = ?')
        params.append(password)
    
    if 'role' in data:
        role = data['role']
        if role not in ('user', 'admin'):
            return jsonify({'error': 'Role must be "user" or "admin"'}), 400
        # Prevent demoting self
        if user_id == session.get('user_id') and role != 'admin':
            return jsonify({'error': 'Cannot change your own role'}), 400
        updates.append('role = ?')
        params.append(role)
    
    if 'is_active' in data:
        # Prevent deactivating self
        if user_id == session.get('user_id') and not data['is_active']:
            return jsonify({'error': 'Cannot deactivate your own account'}), 400
        updates.append('is_active = ?')
        params.append(1 if data['is_active'] else 0)
    
    if not updates:
        return jsonify({'error': 'No fields to update'}), 400
    
    params.append(user_id)
    
    try:
        cursor.execute(f"UPDATE users SET {', '.join(updates)} WHERE id = ?", params)
        db.commit()
        
        return jsonify({'success': True, 'message': 'User updated successfully'})
    except Exception as e:
        if 'UNIQUE constraint' in str(e):
            return jsonify({'error': 'Username already exists'}), 400
        return jsonify({'error': str(e)}), 500


@admin_bp.route('/api/admin/users/<int:user_id>', methods=['DELETE'])
@admin_required
def delete_user(user_id):
    """Delete a user."""
    # Prevent deleting self
    if user_id == session.get('user_id'):
        return jsonify({'error': 'Cannot delete your own account'}), 400
    
    db = get_db()
    cursor = db.cursor()
    
    cursor.execute('SELECT id, username FROM users WHERE id = ?', (user_id,))
    user = cursor.fetchone()
    
    if not user:
        return jsonify({'error': 'User not found'}), 404
    
    cursor.execute('DELETE FROM users WHERE id = ?', (user_id,))
    db.commit()
    
    print(f"🗑️ User deleted: {user['username']}")
    
    return jsonify({'success': True, 'message': f'User "{user["username"]}" deleted'})