replace text with terminal naming

kernel/include/terminal.h

@@ -0,0 +1,20 @@
+#ifndef TERMINAL_H
+#define TERMINAL_H
+
+#include <stdint.h>
+#include <limine.h>
+
+struct terminal {
+    struct limine_framebuffer *framebuffer;
+    int cursor_x;
+    int cursor_y;
+    uint32_t color;
+    int scale;
+};
+
+void terminal_init(struct terminal *term, struct limine_framebuffer *framebuffer, uint32_t color, int scale);
+void terminal_write(struct terminal *term, const char *str);
+void terminal_write_char(struct terminal *term, char c);
+void terminal_event(struct terminal *term, char c);
+
+#endif

kernel/src/kernel.c

@@ -3,7 +3,7 @@
 #include <stdbool.h>
 #include <limine.h>
 #include "../include/colors.h"
-#include "../include/text.h"
+#include "../include/terminal.h"
 
 // Set the base revision to 2, this is recommended as this is the latest
 // base revision described by the Limine boot protocol specification.
@@ -63,7 +63,11 @@ void _start(void) {
     // Fetch the first framebuffer.
     struct limine_framebuffer *framebuffer = framebuffer_request.response->framebuffers[0];
 
-    draw_string(framebuffer, "BaboscOS booted up successfully!", 10, 10, COLOR_WHITE, 2);
+    // init the terminal
+    struct terminal term;
+    terminal_init(&term, framebuffer, COLOR_BLUE, 2);
+
+    terminal_write(&term, "BaboscOS booted up successfully!");
 
     // We're done, just hang...
     hcf();

kernel/src/terminal.c

@@ -0,0 +1,78 @@
+#include "../include/terminal.h"
+#include "../include/font.h"
+
+void terminal_init(struct terminal *term, struct limine_framebuffer *framebuffer, uint32_t color, int scale) {
+    term->framebuffer = framebuffer;
+    term->cursor_x = 0;
+    term->cursor_y = 0;
+    term->color = color;
+    term->scale = scale;
+}
+
+/*
+    This will basically just invoke terminal_write_char for each character in the string
+    but take into account, special things like '\n' for new lines.
+*/
+void terminal_write(struct terminal *term, const char *str) {
+    int start_x = term->cursor_x;
+    while (*str) {
+        if (*str == '\n') { // if the character is a newline..
+            term->cursor_y += 8 * term->scale; // ..offset y
+            term->cursor_x = start_x; // ..and reset x
+        } else {
+            terminal_write_char(term, *str);
+            term->cursor_x += 8 * term->scale; // offset x for each new character so they don't just print on top of each other
+        }
+        str++;
+    }
+}
+
+/*
+    This just writes one character to the terminal
+    It looks up the right glyph to draw from the font array (see ../include/font.h)
+*/
+void terminal_write_char(struct terminal *term, char c) {
+    if (c < 32 || c > 127) return; // only handle ASCII characters
+
+    const uint8_t *glyph = font[c - 32]; // find the glyph for the character that we need to draw
+
+    for (int i = 0; i < 8; i++) { // loop through each row and column of the glyph (8x8)       
+        for (int j = 0; j < 8; j++) {
+
+            // glyph[i] is a byte representing a row of the glyph
+            // (1 << j) creates a mask to check the j-th bit of the byte
+            // if the bit is set, the pixel should be drawn
+            if (glyph[i] & (1 << j)) {
+
+                // next, we need to scale each pixel according to the scale factor (if we want bigger text, for example)
+                for (int dy = 0; dy < term->scale; dy++) { // vertical scale
+                    for (int dx = 0; dx < term->scale; dx++) { // horizontal scale
+
+                        // now that we know what we need to draw, we just calculate the position in the framebuffer
+                        uint32_t *framebuffer_address = (uint32_t *)term->framebuffer->address;
+                        int vertical_position = term->cursor_y + i * term->scale + dy;
+                        int horizontal_position = term->cursor_x + j * term->scale + dx;
+                        int pixels_per_row = term->framebuffer->pitch / 4; // convert pitch from bytes to number of 32-bit pixels per row
+
+                        // and set the pixel color
+                        framebuffer_address[vertical_position * pixels_per_row + horizontal_position] = term->color;
+                    }
+                }
+            }
+        }
+    }
+}
+
+/*
+    This handles special input stuff, like backspace, enter, etc.
+*/
+void terminal_event(struct terminal *term, char c) {
+    if (c == '\b') {
+        if (term->cursor_x > 0) {
+            term->cursor_x -= 8 * term->scale;
+            terminal_write_char(term, ' ');
+        }
+    } else {
+        terminal_write_char(term, c);
+    }
+}