object: Add general parse function

1 files changed, 40 insertions, 0 deletions

diff --git a/object/parse.go b/object/parse.go
new file mode 100644
index 00000000..c87f2713
--- /dev/null
+++ b/object/parse.go
@@ -0,0 +1,40 @@
+package object
+
+import (
+	"fmt"
+
+	"codeberg.org/lindenii/furgit/internal/objectheader"
+	"codeberg.org/lindenii/furgit/objecttype"
+	"codeberg.org/lindenii/furgit/oid"
+)
+
+// ParseObjectWithoutHeader parses a typed object body.
+func ParseObjectWithoutHeader(ty objecttype.Type, body []byte, algo oid.Algorithm) (Object, error) {
+	switch ty {
+	case objecttype.TypeBlob:
+		return ParseBlob(body)
+	case objecttype.TypeTree:
+		return ParseTree(body, algo)
+	case objecttype.TypeCommit:
+		return ParseCommit(body, algo)
+	case objecttype.TypeTag:
+		return ParseTag(body, algo)
+	default:
+		return nil, fmt.Errorf("object: unsupported object type %d", ty)
+	}
+}
+
+// ParseObjectWithHeader parses a loose object in "type size\\x00body" format.
+func ParseObjectWithHeader(raw []byte, algo oid.Algorithm) (Object, error) {
+	ty, size, headerLen, ok := objectheader.Parse(raw)
+	if !ok {
+		return nil, fmt.Errorf("object: malformed object header")
+	}
+
+	body := raw[headerLen:]
+	if int64(len(body)) != size {
+		return nil, fmt.Errorf("object: size mismatch: header says %d bytes, body has %d", size, len(body))
+	}
+
+	return ParseObjectWithoutHeader(ty, body, algo)
+}