veza/apps/web/src/components/layout/DashboardLayout.tsx

import type { ReactNode } from 'react';
import { Header } from './Header';
import { Sidebar } from './Sidebar';
import { GlobalPlayer } from '@/features/player/components/GlobalPlayer';
import { useUIStore } from '@/stores/ui';
import { cn } from '@/lib/utils';
import { AstralBackground } from '../ui/AstralBackground';

interface DashboardLayoutProps {
  children: ReactNode;
}

/**
 * Layout principal "App Shell" - Veza Professional V2
 * 
 * Architecture:
 * - Body: Fixed viewport (overflow-hidden)
 * - Sidebar: Fixed left, z-index high
 * - Main: Scrollable container independent of window
 * - Header: Sticky top within Main
 */
export function DashboardLayout({ children }: DashboardLayoutProps) {
  const { sidebarOpen } = useUIStore();

  return (
    <div className="flex h-screen w-full overflow-hidden relative bg-background">
      {/* 1. Global Background (Fixed z-0) */}
      <AstralBackground />

      {/* 2. Fixed Sidebar (z-90) */}
      <Sidebar />

      {/* 3. Main Content Area (The only thing that scrolls) */}
      <div
        className={cn(
          'flex-1 flex flex-col h-full relative z-10 transition-all duration-500 ease-in-out',
          // Desktop margins: calculated precisely based on sidebar width + gap
          sidebarOpen ? 'lg:ml-72' : 'lg:ml-28',
          // Mobile: no margin (sidebar is overlay)
          'ml-0'
        )}
      >
        {/* Header is part of the flow but stays at top */}
        <Header />

        {/* Scrollable Content Container */}
        {/* pt-20: content below fixed header (h-16) */}
        {/* pb-32 ensures content isn't hidden by the floating player */}
        <main 
          className="flex-1 overflow-y-auto overflow-x-hidden pt-20 pb-32 px-4 md:px-8 custom-scrollbar"
          id="main-scroll-container"
        >
          <div className="max-w-layout-content mx-auto w-full">
            {children}
          </div>
        </main>

        {/* Floating Player (Fixed at bottom of screen, not scroll container) */}
        <div className="absolute bottom-0 left-0 right-0 z-50">
          <GlobalPlayer />
        </div>
      </div>
    </div>
  );
}