4 files changed, 348 insertions, 2 deletions

diff --git a/src/common.hh b/src/common.hh
index b057465..204cf2a 100644
--- a/src/common.hh
+++ b/src/common.hh
@@ -137,6 +137,38 @@ void SetPrintFunction(TPrintFunction *Function);
 void error(char *Text, ...) ATTR_PRINTF(1, 2);
 void print(int Level, char *Text, ...) ATTR_PRINTF(1, 2);
 
-//
+struct TReadStream {
+	// VIRTUAL FUNCTIONS
+	// =========================================================================
+	virtual bool readFlag(void);														// VTABLE[0]
+	virtual uint8 readByte(void) = 0;													// VTABLE[1]
+	virtual uint16 readWord(void);														// VTABLE[2]
+	virtual uint32 readQuad(void);														// VTABLE[3]
+	virtual void readString(char *Buffer, int MaxLength);								// VTABLE[4]
+	virtual void readBytes(uint8 *Buffer, int Count);									// VTABLE[5]
+	virtual bool eof(void) = 0;															// VTABLE[6]
+	virtual void skip(int Count) = 0;													// VTABLE[7]
+};
+
+struct TReadBuffer: TReadStream {
+	// REGULAR FUNCTIONS
+	// =========================================================================
+	TReadBuffer(uint8 *Data, int Size);
+
+	// VIRTUAL FUNCTIONS
+	// =========================================================================
+	uint8 readByte(void) override;
+	uint16 readWord(void) override;
+	uint32 readQuad(void) override;
+	void readBytes(uint8 *Buffer, int Count) override;
+	bool eof(void) override;
+	void skip(int Count) override;
+
+	// DATA
+	// =========================================================================
+	uint8 *Data;
+	int Size;
+	int Position;
+};
 
 #endif //TIBIA_COMMON_HH_
diff --git a/src/script.cc b/src/script.cc
index 5c8c7d7..9db02f7 100644
--- a/src/script.cc
+++ b/src/script.cc
@@ -7,6 +7,8 @@
 // which then becomes ambiguous whether you should free it or not. Used in:
 //	- TReadScriptFile::error
 //	- TWriteScriptFile::error
+//	- TReadBinaryFile::open
+//	- TReadBinaryFile::error
 static char ErrorString[100];
 
 // Helper Functions
@@ -113,7 +115,7 @@ static char *findLast(char *s, char c){
 	return Last;
 }
 
-// TWriteScriptFile
+// TReadScriptFile
 //==============================================================================
 TReadScriptFile::TReadScriptFile(void){
 	this->RecursionDepth = -1;
@@ -788,3 +790,148 @@ void TWriteScriptFile::writeBytesequence(uint8 *Sequence, int Length){
 		this->writeText(s);
 	}
 }
+
+// TReadBinaryFile REGULAR FUNCTIONS
+//==============================================================================
+TReadBinaryFile::TReadBinaryFile(void){
+	this->File = NULL;
+}
+
+void TReadBinaryFile::open(char *FileName){
+	if(this->File != NULL){
+		this->error("File still open");
+	}
+
+	this->File = fopen(FileName, "rb");
+	if(this->File == NULL){
+		snprintf(ErrorString, sizeof(ErrorString),
+				"Cannot open file %s", FileName);
+		throw ErrorString;
+	}
+
+	strcpy(this->Filename, FileName);
+	this->FileSize = -1;
+}
+
+int TReadBinaryFile::close(void){
+	// TODO(fusion): Check if file is NULL?
+	if(fclose(this->File) != 0){
+		int ErrCode = errno;
+		::error("TReadBinaryFile::close: Fehler beim Schließen der Datei.\n");
+		::error("# Datei: %s, Fehlercode: %d (%s)\n",
+				this->Filename, ErrCode, strerror(ErrCode));
+	}
+	this->File = NULL;
+}
+
+void TReadBinaryFile::error(char *Text){
+	if(this->File != NULL){
+		if(fclose(this->File) != 0){
+			::error("TReadBinaryFile::error: Fehler %d beim Schließen der Datei.\n", errno);
+		}
+		this->File = NULL;
+	}
+
+	snprintf(ErrorString, sizeof(ErrorString),
+			"error in binary-file \"%s\": %s.",
+			this->Filename, Text);
+
+	throw ErrorString;
+}
+
+int TReadBinaryFile::getPosition(void){
+	// TODO(fusion): Check if file is NULL?
+	return (int)ftell(this->File);
+}
+
+int TReadBinaryFile::getSize(void){
+	// TODO(fusion): Check if file is NULL?
+	int Size = this->FileSize;
+	if(Size == -1){
+		long Position = ftell(this->File);
+		fseek(this->File, 0, SEEK_END);
+		Size = (int)ftell(this->File);
+		fseek(this->File, Position, SEEK_SET);
+		this->FileSize = Size;
+	}
+	return Size;
+}
+
+void TReadBinaryFile::seek(int Offset){
+	if(this->File == NULL){
+		this->error("File not open for seek");
+	}
+
+	if(Offset < 0){
+		this->error("Negative offset for seek");
+	}
+
+	fseek(this->File, (long)Offset, 0);
+}
+
+// TReadBinaryFile VIRTUAL FUNCTIONS
+//==============================================================================
+TReadBinaryFile::~TReadBinaryFile(void){
+	if(this->File != NULL){
+		::error("TReadBinaryFile::~TReadBinaryFile: Datei %s ist noch offen.\n", this->Filename);
+		if(fclose(this->File) != 0){
+			::error("TReadBinaryFile::~TReadBinaryFile: Fehler %d beim Schließen der Datei.\n", errno);
+		}
+	}
+}
+
+uint8 TReadBinaryFile::readByte(void){
+	uint8 Byte;
+	int Result = (int)fread(&Byte, 1, 1, this->File);
+	if(Result != 1){
+		int ErrCode = errno;
+		int Position = this->getPosition();
+		::error("TReadBinaryFile::readByte: Fehler beim Lesen eines Bytes\n");
+		::error("# Datei: %s, Position: %d, Rückgabewert: %d, Fehlercode: %d (%s)\n",
+				this->Filename, Position, Result, ErrCode, strerror(ErrCode));
+
+		// NOTE(fusion): Close file and make a backup, possibly for further inspection.
+		if(fclose(this->File) != 0){
+			::error("TReadBinaryFile::readByte: Fehler %d beim Schließen der Datei.\n", errno);
+		}
+		SaveFile(this->Filename);
+
+		this->error("Error while reading byte");
+	}
+	return Byte;
+}
+
+void TReadBinaryFile::readBytes(uint8 *Buffer, int Count){
+	int Result = (int)fread(Buffer, 1, Count, this->File);
+	if(Result != Count){
+		int ErrCode = errno;
+		int Position = this->getPosition();
+		::error("TReadBinaryFile::readBytes: Fehler beim Lesen von %d Bytes\n", Count);
+		::error("# Datei: %s, Position %d, Rückgabewert: %d, Fehlercode: %d (%s)\n",
+				this->Filename, Position, Result, ErrCode, strerror(ErrCode));
+
+		// NOTE(fusion): Close file and make a backup, possibly for further inspection.
+		if(fclose(this->File) != 0){
+			::error("TReadBinaryFile::readBytes: Fehler %d beim Schließen der Datei.\n", errno);
+		}
+		SaveFile(this->Filename);
+
+		this->error("Error while reading bytes");
+	}
+}
+
+bool TReadBinaryFile::eof(TReadBinaryFile *this){
+	if(this->File == NULL){
+		this->error("File not open for eof check");
+	}
+
+	return this->getSize() <= this->getPosition();
+}
+
+void TReadBinaryFile::skip(int Count){
+	if(this->File == NULL){
+		this->error("File not open for skip");
+	}
+
+	this->seek(this->getPosition() + Count);
+}
diff --git a/src/script.hh b/src/script.hh
index 0a83196..42ddd2e 100644
--- a/src/script.hh
+++ b/src/script.hh
@@ -101,4 +101,35 @@ struct TWriteScriptFile {
 	int Line;
 };
 
+struct TReadBinaryFile: TReadStream {
+	// REGULAR FUNCTIONS
+	// =========================================================================
+	TReadBinaryFile(void);
+	void open(char *FileName);
+	int close(void);
+	void error(char *Text);
+	int getPosition(void);
+	int getSize(void);
+	void seek(int Offset);
+
+	// VIRTUAL FUNCTIONS
+	// =========================================================================
+	// TODO(fusion): `TReadStream` itself doesn't have a destructor on its VTABLE
+	// which makes me think there is something else going on here or the compiler
+	// optimized it away because it was never used but it seems problematic.
+	virtual ~TReadBinaryFile(void) override;											// VTABLE[8]
+	// Duplicate destructor that also calls operator delete.							// VTABLE[9]
+
+	uint8 readByte(void) override;
+	void readBytes(uint8 *Buffer, int Count) override;
+	bool eof(TReadBinaryFile *this) override;
+	void skip(int Count) override;
+
+	// DATA
+	// =========================================================================
+	FILE *File;
+	char Filename[4096];
+	int FileSize;
+};
+
 #endif //TIBIA_SCRIPT_HH_
diff --git a/src/util.cc b/src/util.cc
index 74c1bf5..5cdd933 100644
--- a/src/util.cc
+++ b/src/util.cc
@@ -40,3 +40,139 @@ void print(int Level, char *Text, ...){
 		printf("%s", s);
 	}
 }
+
+// TReadStream
+// =============================================================================
+bool TReadStream::readFlag(void){
+	return this->readByte() != 0;
+}
+
+uint16 TReadStream::readWord(void){
+	// NOTE(fusion): Data is encoded in little endian.
+	uint8 Byte0 = this->readByte();
+	uint8 Byte1 = this->readByte();
+	return ((uint16)Byte1 << 8) | (uint16)Byte0;
+}
+
+uint32 TReadStream::readQuad(void){
+	// NOTE(fusion): Data is encoded in little endian.
+	uint8 Byte0 = this->readByte();
+	uint8 Byte1 = this->readByte();
+	uint8 Byte2 = this->readByte();
+	uint8 Byte3 = this->readByte();
+	return ((uint32)Byte3 << 24) | ((uint32)Byte2 << 16)
+			| ((uint32)Byte1 << 8) | (uint32)Byte0;
+}
+
+void TReadStream::readString(char *Buffer, int MaxLength){
+	if(Buffer == NULL || MaxLength == 0){
+		error("TReadStream::readString: Übergebener Puffer existiert nicht.\n");
+		throw "internal error";
+	}
+
+	int Length = (int)this->readWord();
+	if(Length == 0xFFFF){
+		Length = (int)this->readQuad();
+	}
+
+	if(Length > 0){
+		if(MaxLength < 0 || MaxLength > Length){
+			this->readBytes(Buffer, Length);
+			Buffer[Length] = 0;
+		}else{
+			this->readBytes(Buffer, MaxLength - 1);
+			this->skip(Length - MaxLength + 1);
+			Buffer[MaxLength - 1] = 0;
+		}
+	}else{
+		Buffer[0] = 0;
+	}
+}
+
+void TReadStream::readBytes(uint8 *Buffer, int Count){
+	if(Buffer == NULL){
+		error("TReadStream::readBytes: Übergebener Puffer existiert nicht.\n");
+		throw "internal error";
+	}
+
+	for(int i = 0; i < Count; i += 1){
+		Buffer[i] = this->readByte();
+	}
+}
+
+// TReadBuffer
+// =============================================================================
+TReadBuffer::TReadBuffer(uint8 *Data, int Size){
+	if(Data == NULL){
+		error("TReadBuffer::TReadBuffer: data ist NULL.\n");
+		Size = 0;
+	}else if(Size < 0){
+		error("TReadBuffer::TReadBuffer: Ungültige Datengröße %d.\n", Size);
+		Size = 0;
+	}
+
+	this->Data = Data;
+	this->Size = Size;
+	this->Position = 0;
+}
+
+uint8 TReadBuffer::readByte(void){
+	if((this->Size - this->Position) < 1){
+		throw "buffer empty";
+	}
+
+	uint8 Byte = this->Data[this->Position];
+	this->Position += 1;
+	return Byte;
+}
+
+uint16 TReadBuffer::readWord(void){
+	if((this->Size - this->Position) < 2){
+		throw "buffer empty";
+	}
+
+	uint8 Byte0 = this->Data[this->Position];
+	uint8 Byte1 = this->Data[this->Position + 1];
+	this->Position += 2;
+	return ((uint16)Byte1 << 8) | (uint16)Byte0;
+}
+
+uint32 TReadBuffer::readQuad(void){
+	if((this->Size - this->Position) < 4){
+		throw "buffer empty";
+	}
+
+	uint8 Byte0 = this->Data[this->Position];
+	uint8 Byte1 = this->Data[this->Position + 1];
+	uint8 Byte2 = this->Data[this->Position + 2];
+	uint8 Byte3 = this->Data[this->Position + 3];
+	this->Position += 4;
+	return ((uint32)Byte3 << 24) | ((uint32)Byte2 << 16)
+			| ((uint32)Byte1 << 8) | (uint32)Byte0;
+}
+
+void TReadBuffer::readBytes(uint8 *Buffer, int Count){
+	if(Buffer == NULL || Count <= 0){
+		error("TReadBuffer::readBytes: Übergebener Puffer existiert nicht.\n");
+		throw "buffer not existing";
+	}
+
+	if((this->Size - this->Position) < Count){
+		throw "buffer empty";
+	}
+
+	memcpy(Buffer, &this->Data[this->Position], Count);
+	this->Position += Count;
+}
+
+bool TReadBuffer::eof(void){
+	return this->Size <= this->Position;
+}
+
+void TReadBuffer::skip(int Count){
+	if((this->Size - this->Position) < Count){
+		throw "buffer empty";
+	}
+
+	this->Position += Count;
+}