Store terminal characters.

targets/_any/include/os/tty.hpp

@@ -34,12 +34,26 @@ struct VgaDoubleColor
 {
     VgaColor foreground : 4 = VgaColor::LIGHT_GREY;
     VgaColor background : 4 = VgaColor::BLACK;
+
+    [[nodiscard]] VgaDoubleColor swapped() const noexcept
+    {
+        return VgaDoubleColor{.foreground = background, .background = foreground};
+    }
+};
+
+struct VgaCharacter
+{
+    char character = '\0';
+    VgaDoubleColor color = {};
 };
 
 void initialize() noexcept;
 void setColor(VgaDoubleColor color) noexcept;
+const VgaDoubleColor& getColor() noexcept;
 void putEntryAt(char chr, VgaDoubleColor color, size_t posX, size_t posY) noexcept;
+VgaCharacter getEntryAt(size_t posX, size_t posY) noexcept;
 void putChar(char chr) noexcept;
+void putChar(char chr, VgaDoubleColor color) noexcept;
 void deleteChar() noexcept;
 void write(const char* data, size_t size) noexcept;
 void write(const char* data) noexcept;

targets/_any/src/os/tty.cpp

@@ -18,7 +18,7 @@ size_t gTerminalWidth = 0;
 size_t gTerminalHeight = 0;
 VgaDoubleColor gTerminalColor = VgaDoubleColor();
 // uint16_t* gTerminalBuffer = reinterpret_cast<uint16_t*>(0xB8000);
-std::vector<uint16_t> gTerminalBuffer;
+std::vector<VgaCharacter> gTerminalBuffer;
 psf::Font gTerminalFont;
 std::string gReadBuffer;
 
@@ -42,6 +42,10 @@ void newline()
     else
     {
         draw::scrollBy(0, static_cast<int>(gTerminalFont.getGlyphHeight()) + 1);
+        std::memmove(&gTerminalBuffer[0], &gTerminalBuffer[gTerminalWidth], (gTerminalHeight - 1) * gTerminalWidth * sizeof(VgaCharacter));
+        for (std::size_t posX = 0; posX < gTerminalWidth; ++posX) {
+            putEntryAt('\0', gTerminalColor, posX, gTerminalHeight - 1);
+        }
     }
 }
 }
@@ -56,19 +60,38 @@ void setColor(VgaDoubleColor color) noexcept
     gTerminalColor = color;
 }
 
+const VgaDoubleColor& getColor() noexcept
+{
+    return gTerminalColor;
+}
+
 void putEntryAt(char chr, VgaDoubleColor color, size_t posX, size_t posY) noexcept
 {
     draw::character(
         /* posX = */ (gTerminalFont.getGlyphWidth() + 1) * posX,
         /* posY = */ (gTerminalFont.getGlyphHeight() + 1) * posY,
         /* font = */ gTerminalFont,
-        /* chr  = */ chr,
+        /* chr  = */ chr ? chr : ' ',
         /* fgColor = */ draw::VGA_PIXELS[static_cast<uint8_t>(color.foreground)],
         /* bgColor = */ draw::VGA_PIXELS[static_cast<uint8_t>(color.background)]
     );
+    gTerminalBuffer[posY * gTerminalHeight + posX] = {
+        .character = chr,
+        .color = color
+    };
+}
+
+VgaCharacter getEntryAt(size_t posX, size_t posY) noexcept
+{
+    return gTerminalBuffer[posY * gTerminalHeight + posX];
 }
 
 void putChar(char chr) noexcept
+{
+    putChar(chr, gTerminalColor);
+}
+
+void putChar(char chr, VgaDoubleColor color) noexcept
 {
     if (chr == '\n')
     {
@@ -76,7 +99,7 @@ void putChar(char chr) noexcept
         return;
     }
 
-    putEntryAt(chr, gTerminalColor, gTerminalColumn, gTerminalRow);
+    putEntryAt(chr, color, gTerminalColumn, gTerminalRow);
     if (++gTerminalColumn == gTerminalWidth)
     {
         newline();
@@ -107,13 +130,26 @@ void write(const char* data) noexcept
     write(data, std::strlen(data));
 }
 
+unsigned rowLength(unsigned row)
+{
+    unsigned length = 0;
+    for (; length < gTerminalWidth; ++length)
+    {
+        if (getEntryAt(length, row).character == '\0') {
+            break;
+        }
+    }
+    return length;
+}
+
 const std::string& readLine() noexcept
 {
     gReadBuffer.clear();
     while(true)
     {
         char chr = '\0';
-        putChar('_');
+
+        putChar(' ', gTerminalColor.swapped());
         while (!baos::ps2::readChar(chr)); // TODO: arrow key navigation and stuff
         deleteChar();
         if (chr == '\b')
@@ -142,6 +178,7 @@ bool setPSFFont(const void* data, size_t length) noexcept
     gTerminalFont = newFont;
     gTerminalWidth = draw::getPrimaryFramebuffer().getWidth() / (gTerminalFont.getGlyphWidth() + 1);
     gTerminalHeight = draw::getPrimaryFramebuffer().getHeight() / (gTerminalFont.getGlyphHeight() + 1);
+    gTerminalBuffer.resize(gTerminalWidth * gTerminalHeight);
     return true;
 }
 }