Began writing Compress for ROM

src/app/rom.h

@@ -21,6 +21,8 @@
 #include "app/core/constants.h"
 #include "app/gfx/bitmap.h"
 
+#define BUILD_HEADER(command, length) (command << 5) + (length - 1)
+
 namespace yaze {
 namespace app {
 
@@ -29,6 +31,10 @@ constexpr int kCommandByteFill = 1;
 constexpr int kCommandWordFill = 2;
 constexpr int kCommandIncreasingFill = 3;
 constexpr int kCommandRepeatingBytes = 4;
+constexpr int kMaxLengthNormalHeader = 32;
+constexpr int kMaxLengthCompression = 1024;
+constexpr int kNintendoMode1 = 0;
+constexpr int kNintendoMode2 = 1;
 constexpr uchar kGraphicsBitmap[8] = {0x80, 0x40, 0x20, 0x10,
                                       0x08, 0x04, 0x02, 0x01};
 
@@ -40,6 +46,23 @@ struct OWMapTiles {
   OWBlockset special_world;  // 32 maps
 } typedef OWMapTiles;
 
+typedef struct s_compression_piece compression_piece;
+
+struct s_compression_piece {
+  char command;
+  unsigned int length;
+  char* argument;
+  unsigned int argument_length;
+  compression_piece* next;
+};
+
+struct CompressionPiece {
+  uchar command;
+  uint length;
+  uchar* argument;
+  uint argument_length;
+};
+
 class ROM {
  public:
   absl::Status LoadFromFile(const absl::string_view& filename);
@@ -48,6 +71,11 @@ class ROM {
 
   // absl::Status SaveOverworld();
 
+  absl::StatusOr<Bytes> CompressGraphics(const uint pos, const uint length);
+  absl::StatusOr<Bytes> CompressOverworld(const uint pos, const uint length);
+  absl::StatusOr<Bytes> Compress(const uint start, const uint length,
+                                 char mode);
+
   absl::StatusOr<Bytes> DecompressGraphics(int pos, int size);
   absl::StatusOr<Bytes> DecompressOverworld(int pos, int size);
   absl::StatusOr<Bytes> Decompress(int offset, int size = 0x800,