#include <efi.h>
#include <efilib.h>

EFI_STATUS
EFIAPI
efi_main(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable)
{
    EFI_STATUS Status;
    EFI_INPUT_KEY Key;
    
    // Initialize the GNU-EFI library
    InitializeLib(ImageHandle, SystemTable);
    
    // Clear the screen
    uefi_call_wrapper(ST->ConOut->ClearScreen, 1, ST->ConOut);
    
    // Set text color to light green
    uefi_call_wrapper(ST->ConOut->SetAttribute, 2, ST->ConOut, 
                     EFI_TEXT_ATTR(EFI_LIGHTGREEN, EFI_BLACK));
    
    // Print welcome messages
    Print(L"================================================\n\r");
    Print(L"  Welcome to Simple UEFI Operating System!\n\r");
    Print(L"================================================\n\r");
    Print(L"\n\r");
    Print(L"System Information:\n\r");
    Print(L"  UEFI Firmware Vendor: %s\n\r", ST->FirmwareVendor);
    Print(L"  UEFI Firmware Revision: %d.%d\n\r", 
          ST->FirmwareRevision >> 16, ST->FirmwareRevision & 0xFFFF);
    Print(L"\n\r");
    
    // Display some runtime services info
    Print(L"Available Services:\n\r");
    Print(L"  - Console Input/Output: Active\n\r");
    Print(L"  - Runtime Services: Active\n\r");
    Print(L"  - Boot Services: Active\n\r");
    Print(L"\n\r");
    
    // Simple command loop
    Print(L"Commands:\n\r");
    Print(L"  'h' - Display help\n\r");
    Print(L"  'i' - Display system info\n\r");
    Print(L"  'c' - Clear screen\n\r");
    Print(L"  'q' - Shutdown\n\r");
    Print(L"\n\r");
    Print(L"Press a key to start...\n\r");
    
    while (TRUE) {
        // Wait for key press
        Status = uefi_call_wrapper(ST->ConIn->ReadKeyStroke, 2, 
                                   ST->ConIn, &Key);
        
        if (EFI_ERROR(Status)) {
            continue;
        }
        
        // Handle commands
        if (Key.UnicodeChar == L'q' || Key.UnicodeChar == L'Q') {
            Print(L"\n\rShutting down...\n\r");
            // Reset the system
            uefi_call_wrapper(RT->ResetSystem, 4, EfiResetShutdown, 
                            EFI_SUCCESS, 0, NULL);
        }
        else if (Key.UnicodeChar == L'h' || Key.UnicodeChar == L'H') {
            Print(L"\n\r=== Help ===\n\r");
            Print(L"This is a minimal UEFI operating system.\n\r");
            Print(L"It demonstrates basic UEFI functionality.\n\r");
            Print(L"\n\r");
        }
        else if (Key.UnicodeChar == L'i' || Key.UnicodeChar == L'I') {
            Print(L"\n\r=== System Info ===\n\r");
            Print(L"Firmware Vendor: %s\n\r", ST->FirmwareVendor);
            Print(L"Firmware Revision: %d.%d\n\r", 
                  ST->FirmwareRevision >> 16, ST->FirmwareRevision & 0xFFFF);
            Print(L"UEFI Specification: %d.%d\n\r",
                  ST->Hdr.Revision >> 16, ST->Hdr.Revision & 0xFFFF);
            Print(L"\n\r");
        }
        else if (Key.UnicodeChar == L'c' || Key.UnicodeChar == L'C') {
            uefi_call_wrapper(ST->ConOut->ClearScreen, 1, ST->ConOut);
            Print(L"Screen cleared. Press 'h' for help.\n\r");
        }
        else if (Key.UnicodeChar >= 32 && Key.UnicodeChar < 127) {
            // Echo printable characters
            Print(L"%c", Key.UnicodeChar);
        }
        else if (Key.UnicodeChar == L'\r') {
            Print(L"\n\r> ");
        }
    }
    
    return EFI_SUCCESS;
}