From 6e7d06299a5aef466d4243bf21f1dcadc8f49456 Mon Sep 17 00:00:00 2001
From: MadMaurice <madmaurice@zom.bi>
Date: Thu, 31 Aug 2023 23:53:20 +0200
Subject: [PATCH] Implement class for cartridge and rudimentary ROM inspector

---
 .gitignore              |  1 +
 Makeconf                |  3 ++-
 Makefile                |  4 ++++
 cartridge/cartridge.cpp | 22 ++++++++++++++++++++++
 cartridge/cartridge.h   | 37 +++++++++++++++++++++++++++++++++++++
 cartridge/inspector.cpp | 20 ++++++++++++++++++++
 6 files changed, 86 insertions(+), 1 deletion(-)
 create mode 100644 cartridge/cartridge.cpp
 create mode 100644 cartridge/cartridge.h
 create mode 100644 cartridge/inspector.cpp

diff --git a/.gitignore b/.gitignore
index b6ea3c3..b7a2d4f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,4 @@
 /vgbc
 /libemu.a
 /vgbc.test
+/vgbc.inspect
diff --git a/Makeconf b/Makeconf
index 086f66a..d17ba72 100644
--- a/Makeconf
+++ b/Makeconf
@@ -5,6 +5,7 @@ modules := memory/device \
            memory/register \
 		   memory/bank \
            cpu/cpu \
-           cpu/decoder
+           cpu/decoder \
+           cartridge/cartridge
 
 CXX_FLAGS := -I $(CURDIR)
diff --git a/Makefile b/Makefile
index 97d6d50..9f872e7 100644
--- a/Makefile
+++ b/Makefile
@@ -34,3 +34,7 @@ vgbc: main.o libemu.a
 vgbc.test: $(test-objs) libemu.a
 	@echo " ==> link $@"; \
 	g++ $(CXX_FLAGS) -o $@ $^
+
+vgbc.inspect: cartridge/inspector.o libemu.a
+	@echo " ==> link $@"; \
+	g++ $(CXX_FLAGS) -o $@ $^
diff --git a/cartridge/cartridge.cpp b/cartridge/cartridge.cpp
new file mode 100644
index 0000000..e126daf
--- /dev/null
+++ b/cartridge/cartridge.cpp
@@ -0,0 +1,22 @@
+#include <cartridge/cartridge.h>
+#include <cstring>
+
+Cartridge::Cartridge(std::ifstream& file)
+{
+  _size = file.seekg(0, std::ios_base::end).tellg();
+  file.seekg(0, std::ios_base::beg);
+
+  _data = new u8[_size];
+
+  file.read(reinterpret_cast<char*>(_data), _size);
+
+  std::strncpy(_title, (char*)&_data[TITLE], 16);
+  _title[16] = '\0';
+}
+
+u8 Cartridge::operator[](size_t addr)
+{
+  if(addr >= _size)
+    return 0xFFu;
+  return _data[addr];
+}
diff --git a/cartridge/cartridge.h b/cartridge/cartridge.h
new file mode 100644
index 0000000..2364aaa
--- /dev/null
+++ b/cartridge/cartridge.h
@@ -0,0 +1,37 @@
+#pragma once
+
+#include <misc/types.h>
+
+#include <fstream>
+
+enum CartridgeType : u8 {
+  ROM_ONLY = 0x00,
+  MBC1 = 0x01,
+  MBC1_RAM = 0x02,
+  MBC1_RAM_BATTERY = 0x03,
+};
+
+class Cartridge {
+private:
+  u8* _data;
+  size_t _size;
+
+  char _title[17];
+
+  enum Offsets {
+    TITLE = 0x0134,
+    MANU_CODE = 0x013F,
+  };
+public:
+  Cartridge(std::ifstream& file);
+
+  u8 operator[](size_t addr);
+
+  inline
+  const char* title()
+  { return _title; }
+
+  inline
+  size_t size()
+  { return _size; }
+};
diff --git a/cartridge/inspector.cpp b/cartridge/inspector.cpp
new file mode 100644
index 0000000..2bf6daa
--- /dev/null
+++ b/cartridge/inspector.cpp
@@ -0,0 +1,20 @@
+#include <iostream>
+#include <fstream>
+#include <cartridge/cartridge.h>
+
+int main(int argc, char** argv)
+{
+  if(argc < 2) return 1;
+
+  std::ifstream file;
+  file.open(argv[1]);
+
+  Cartridge cart(file);
+
+  std::cout << std::hex << "Path: " << argv[1] << " (size " << cart.size() << ")" << std::endl;
+  std::cout << "title: " << cart.title() << std::endl;
+  std::cout << std::hex << "cgb flag: " << (int)cart[0x143] << std::endl;
+  std::cout << std::hex << "type: " << (int)cart[0x147] << std::endl;
+
+  return 0;
+}