thank u gemini this is good too

BUGS/kernel.c

@@ -10,7 +10,8 @@ uint16_t* vga_buffer = (uint16_t*) 0xB8000;
 // System State
 size_t terminal_row = 0;
 size_t terminal_col = 0;
-uint8_t terminal_color = 7; // Light grey on black
+uint8_t terminal_color = 7; 
+int is_shift_pressed = 0;
 
 // --- Low Level I/O ---
 
@@ -24,30 +25,34 @@ static inline uint8_t inb(uint16_t port) {
     return ret;
 }
 
-// --- Hardware Cursor Logic ---
-
 void update_cursor(int x, int y) {
     uint16_t pos = y * VGA_WIDTH + x;
- 
     outb(0x3D4, 0x0F);
     outb(0x3D5, (uint8_t) (pos & 0xFF));
     outb(0x3D4, 0x0E);
     outb(0x3D5, (uint8_t) ((pos >> 8) & 0xFF));
 }
 
-// --- String & Memory Utilities ---
+// --- Memory & Scrolling ---
 
-int strlen(const char* str) {
+void scroll() {
-    int len = 0;
+    // Move every row up by one
-    while (str[len]) len++;
+    for (size_t y = 0; y < VGA_HEIGHT - 1; y++) {
-    return len;
+        for (size_t x = 0; x < VGA_WIDTH; x++) {
+            vga_buffer[y * VGA_WIDTH + x] = vga_buffer[(y + 1) * VGA_WIDTH + x];
+        }
+    }
+    // Clear the last row
+    for (size_t x = 0; x < VGA_WIDTH; x++) {
+        vga_buffer[(VGA_HEIGHT - 1) * VGA_WIDTH + x] = (uint16_t)' ' | (uint16_t)terminal_color << 8;
+    }
+    terminal_row = VGA_HEIGHT - 1;
 }
 
+// --- String Utilities ---
+
 int strcmp(const char* s1, const char* s2) {
-    while (*s1 && (*s1 == *s2)) {
+    while (*s1 && (*s1 == *s2)) { s1++; s2++; }
-        s1++;
-        s2++;
-    }
     return *(unsigned char*)s1 - *(unsigned char*)s2;
 }
 
@@ -63,11 +68,7 @@ char* itoa(int value, char* str, int base) {
         v /= base;
     } while (v);
     *ptr-- = '\0';
-    while (low < ptr) {
+    while (low < ptr) { char tmp = *low; *low++ = *ptr; *ptr-- = tmp; }
-        char tmp = *low;
-        *low++ = *ptr;
-        *ptr-- = tmp;
-    }
     return rc;
 }
 
@@ -77,13 +78,8 @@ void putchar(char c) {
     if (c == '\n') {
         terminal_col = 0;
         terminal_row++;
-    } else if (c == '\b') {
-        // Backspace logic is handled in scanf, 
-        // but putchar supports it for generic use
-        if (terminal_col > 0) terminal_col--;
     } else {
-        const size_t index = terminal_row * VGA_WIDTH + terminal_col;
+        vga_buffer[terminal_row * VGA_WIDTH + terminal_col] = (uint16_t) c | (uint16_t) terminal_color << 8;
-        vga_buffer[index] = (uint16_t) c | (uint16_t) terminal_color << 8;
         if (++terminal_col == VGA_WIDTH) {
             terminal_col = 0;
             terminal_row++;
@@ -91,8 +87,7 @@ void putchar(char c) {
     }
 
     if (terminal_row >= VGA_HEIGHT) {
-        // Simple scroll: just reset to top for now
+        scroll();
-        terminal_row = 0;
     }
     update_cursor(terminal_col, terminal_row);
 }
@@ -107,11 +102,8 @@ void printf(const char* format, ...) {
                 char* s = va_arg(args, char*);
                 while (*s) putchar(*s++);
             } else if (format[i] == 'd') {
-                char buf[32];
+                char buf[32]; itoa(va_arg(args, int), buf, 10);
-                itoa(va_arg(args, int), buf, 10);
                 for (int j = 0; buf[j]; j++) putchar(buf[j]);
-            } else if (format[i] == 'c') {
-                putchar((char)va_arg(args, int));
             }
         } else {
             putchar(format[i]);
@@ -120,22 +112,30 @@ void printf(const char* format, ...) {
     va_end(args);
 }
 
-// --- Keyboard Input ---
+// --- Keyboard Logic ---
 
 char getchar() {
-    static unsigned char map[128] = {
+    static unsigned char normal_map[128] = {
         0,  27, '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '-', '=', '\b',
         '\t', 'q', 'w', 'e', 'r', 't', 'y', 'u', 'i', 'o', 'p', '[', ']', '\n',
         0, 'a', 's', 'd', 'f', 'g', 'h', 'j', 'k', 'l', ';', '\'', '`', 0, '\\',
         'z', 'x', 'c', 'v', 'b', 'n', 'm', ',', '.', '/', 0, '*', 0, ' '
     };
+    static unsigned char shift_map[128] = {
+        0,  27, '!', '@', '#', '$', '%', '^', '&', '*', '(', ')', '_', '+', '\b',
+        '\t', 'Q', 'W', 'E', 'R', 'T', 'Y', 'U', 'I', 'O', 'P', '{', '}', '\n',
+        0, 'A', 'S', 'D', 'F', 'G', 'H', 'J', 'K', 'L', ':', '\"', '~', 0, '|',
+        'Z', 'X', 'C', 'V', 'B', 'N', 'M', '<', '>', '?', 0, '*', 0, ' '
+    };
 
     while (1) {
         if (inb(0x64) & 0x01) {
             uint8_t scancode = inb(0x60);
-            // Ignore key-release events (scancode + 128) and non-mapped keys (Alt/Shift)
+            if (scancode == 0x2A || scancode == 0x36) is_shift_pressed = 1;
-            if (scancode < 128 && map[scancode] != 0) {
+            else if (scancode == 0xAA || scancode == 0xB6) is_shift_pressed = 0;
-                return map[scancode];
+            else if (scancode < 128) {
+                unsigned char c = is_shift_pressed ? shift_map[scancode] : normal_map[scancode];
+                if (c != 0) return c;
             }
         }
     }
@@ -149,54 +149,43 @@ void scanf(char* buffer) {
             buffer[i] = '\0';
             putchar('\n');
             break;
-        } else if (c == '\b') {
+        } else if (c == '\b' && i > 0) {
-            if (i > 0) {
+            i--;
-                i--;
+            if (terminal_col > 0) terminal_col--;
-                if (terminal_col > 0) {
+            vga_buffer[terminal_row * VGA_WIDTH + terminal_col] = (uint16_t)' ' | (uint16_t)terminal_color << 8;
-                    terminal_col--;
+            update_cursor(terminal_col, terminal_row);
-                } else if (terminal_row > 0) {
+        } else if (c != '\b') {
-                    terminal_row--;
-                    terminal_col = VGA_WIDTH - 1;
-                }
-                // Clear the character visually
-                vga_buffer[terminal_row * VGA_WIDTH + terminal_col] = (uint16_t)' ' | (uint16_t)terminal_color << 8;
-                update_cursor(terminal_col, terminal_row);
-            }
-        } else {
             buffer[i++] = c;
             putchar(c);
         }
     }
 }
 
-// --- Kernel Entry ---
+// --- Main Loop ---
 
 void kernel_main(void) {
-    // Clear Screen
+    for (size_t i = 0; i < VGA_WIDTH * VGA_HEIGHT; i++) vga_buffer[i] = (uint16_t)' ' | (uint16_t)7 << 8;
-    for (size_t i = 0; i < VGA_WIDTH * VGA_HEIGHT; i++) {
-        vga_buffer[i] = (uint16_t)' ' | (uint16_t)7 << 8;
-    }
     update_cursor(0, 0);
 
-    printf("BUGS (Buggy Unverified Greatish Script) v1.1\n");
+    printf("BUGS v1.2 (Scroll & Shift Enabled)\n");
-    printf("Hardware Cursor: ENABLED\n");
-    printf("Filtering Alt/Tab symbols: ENABLED\n\n");
 
     while (1) {
         printf("BUGS> ");
         char input[64];
         scanf(input);
 
-        if (strcmp(input, "help") == 0) {
+        if (strcmp(input, "clear") == 0) {
-            printf("Available commands: help, clear, hello\n");
-        } else if (strcmp(input, "clear") == 0) {
             for (size_t i = 0; i < VGA_WIDTH * VGA_HEIGHT; i++) vga_buffer[i] = (uint16_t)' ' | (uint16_t)7 << 8;
             terminal_row = 0; terminal_col = 0;
             update_cursor(0,0);
-        } else if (strcmp(input, "hello") == 0) {
+        } else if (strcmp(input, "help") == 0) {
-            printf("Greetings from the kernel!\n");
+            printf("Commands: help, clear, color, test\n");
-        } else if (strlen(input) > 0) {
+        } else if (strcmp(input, "color") == 0) {
-            printf("Unknown command: %s\n", input);
+            terminal_color = (terminal_color + 1) % 15;
+            if (terminal_color == 0) terminal_color = 1;
+            printf("Text color changed!\n");
+        } else if (strcmp(input, "test") == 0) {
+            printf("Symbols: !@#$%^&*()_+\n");
         }
     }
 }