From a366d2b104a210b813dc60a2b7d1219f3d1ff092 Mon Sep 17 00:00:00 2001
From: Alex Yatskov <alex@foosoft.net>
Date: Wed, 23 Jan 2019 20:06:32 -0800
Subject: [PATCH] add read methods for basic types

---
 formats/dcc/dcc.go          | 38 ++++++++++--------------
 streaming/bitreader.go      | 59 ++++++++++++++++++++++++-------------
 streaming/streaming_test.go |  5 ++--
 3 files changed, 55 insertions(+), 47 deletions(-)

diff --git a/formats/dcc/dcc.go b/formats/dcc/dcc.go
index 66c2335..d4ab79e 100644
--- a/formats/dcc/dcc.go
+++ b/formats/dcc/dcc.go
@@ -88,69 +88,61 @@ func NewFromReader(reader io.ReadSeeker) (*Sprite, error) {
 func readDirectionHeader(reader io.ReadSeeker) (*directionHeader, error) {
 	r := streaming.NewBitReader(reader)
 
-	codedSize, err := r.ReadBitsUnsigned(32)
+	var (
+		header directionHeader
+		err    error
+	)
+
+	header.CodedSize, err = r.ReadUint32(32)
 	if err != nil {
 		return nil, err
 	}
 
-	hasRawPixelEncoding, err := r.ReadBitsUnsigned(1)
+	header.HasRawPixelEncoding, err = r.ReadBool()
 	if err != nil {
 		return nil, err
 	}
 
-	compressEqualCells, err := r.ReadBitsUnsigned(1)
+	header.CompressEqualCells, err = r.ReadBool()
 	if err != nil {
 		return nil, err
 	}
 
-	variable0Bits, err := r.ReadBitsUnsigned(4)
+	header.Variable0Bits, err = r.ReadUint32(4)
 	if err != nil {
 		return nil, err
 	}
 
-	widthBits, err := r.ReadBitsUnsigned(4)
+	header.WidthBits, err = r.ReadUint32(4)
 	if err != nil {
 		return nil, err
 	}
 
-	heightBits, err := r.ReadBitsUnsigned(4)
+	header.HeightBits, err = r.ReadUint32(4)
 	if err != nil {
 		return nil, err
 	}
 
-	offsetXBits, err := r.ReadBitsUnsigned(4)
+	header.OffsetXBits, err = r.ReadInt32(4)
 	if err != nil {
 		return nil, err
 	}
 
-	offsetYBits, err := r.ReadBitsUnsigned(4)
+	header.OffsetYBits, err = r.ReadInt32(4)
 	if err != nil {
 		return nil, err
 	}
 
-	optionalBytesBits, err := r.ReadBitsUnsigned(4)
+	header.OptionalBytesBits, err = r.ReadUint32(4)
 	if err != nil {
 		return nil, err
 	}
 
-	codedBytesBits, err := r.ReadBitsUnsigned(4)
+	header.CodedBytesBits, err = r.ReadUint32(4)
 	if err != nil {
 		return nil, err
 	}
 
-	header := directionHeader{
-		CodedSize:           uint32(codedSize),
-		HasRawPixelEncoding: hasRawPixelEncoding == 1,
-		CompressEqualCells:  compressEqualCells == 1,
-		Variable0Bits:       uint32(variable0Bits),
-		WidthBits:           uint32(widthBits),
-		HeightBits:          uint32(heightBits),
-		OffsetXBits:         int32(offsetXBits),
-		OffsetYBits:         int32(offsetYBits),
-		OptionalBytesBits:   uint32(optionalBytesBits),
-		CodedBytesBits:      uint32(codedBytesBits),
-	}
-
 	return &header, nil
 }
 
diff --git a/streaming/bitreader.go b/streaming/bitreader.go
index 8c82a91..90706a5 100644
--- a/streaming/bitreader.go
+++ b/streaming/bitreader.go
@@ -1,7 +1,6 @@
 package streaming
 
 import (
-	"errors"
 	"io"
 )
 
@@ -15,8 +14,43 @@ func NewBitReader(reader io.Reader) *BitReader {
 	return &BitReader{reader: reader}
 }
 
-func (r *BitReader) ReadBitsSigned(count int) (int64, error) {
-	value, err := r.readBits(count)
+func (r *BitReader) ReadBool() (bool, error) {
+	value, err := r.ReadUint64(1)
+	return value == 1, err
+}
+
+func (r *BitReader) ReadInt8(count int) (int8, error) {
+	value, err := r.ReadInt64(count)
+	return int8(value), err
+}
+
+func (r *BitReader) ReadUint8(count int) (uint8, error) {
+	value, err := r.ReadUint64(count)
+	return uint8(value), err
+}
+
+func (r *BitReader) ReadInt16(count int) (int16, error) {
+	value, err := r.ReadInt64(count)
+	return int16(value), err
+}
+
+func (r *BitReader) ReadUint16(count int) (uint16, error) {
+	value, err := r.ReadUint64(count)
+	return uint16(value), err
+}
+
+func (r *BitReader) ReadInt32(count int) (int32, error) {
+	value, err := r.ReadInt64(count)
+	return int32(value), err
+}
+
+func (r *BitReader) ReadUint32(count int) (uint32, error) {
+	value, err := r.ReadUint64(count)
+	return uint32(value), err
+}
+
+func (r *BitReader) ReadInt64(count int) (int64, error) {
+	value, err := r.ReadUint64(count)
 	if err != nil {
 		return 0, err
 	}
@@ -31,24 +65,7 @@ func (r *BitReader) ReadBitsSigned(count int) (int64, error) {
 	return int64(value), nil
 }
 
-func (r *BitReader) ReadBitsUnsigned(count int) (uint64, error) {
-	return r.readBits(count)
-}
-
-func (r *BitReader) ReadBitFlag() (bool, error) {
-	value, err := r.readBits(1)
-	if err != nil {
-		return false, err
-	}
-
-	return value == 1, nil
-}
-
-func (r *BitReader) readBits(count int) (uint64, error) {
-	if count > 64 {
-		return 0, errors.New("cannot read more than 64 bits at a time")
-	}
-
+func (r *BitReader) ReadUint64(count int) (uint64, error) {
 	var value uint64
 	for count > 0 {
 		bitOffset := r.offset % 8
diff --git a/streaming/streaming_test.go b/streaming/streaming_test.go
index 726e7c4..9624296 100644
--- a/streaming/streaming_test.go
+++ b/streaming/streaming_test.go
@@ -18,19 +18,18 @@ func TestBitReader(t *testing.T) {
 	r := NewBitReader(bytes.NewReader(data))
 
 	readPass := func(c int, v uint64) {
-		if value, err := r.ReadBitsUnsigned(c); value != v || err != nil {
+		if value, err := r.ReadUint64(c); value != v || err != nil {
 			t.Fail()
 		}
 	}
 
 	readFail := func(c int) {
-		if value, err := r.ReadBitsUnsigned(c); value != 0 || err == nil {
+		if value, err := r.ReadUint64(c); value != 0 || err == nil {
 			t.Fail()
 		}
 	}
 
 	readPass(0, 0x00)
-	readFail(65)
 	readPass(2, 0x01)
 	readPass(2, 0x02)
 	readPass(3, 0x04)