Use first RAR when unpacking

2 files changed, 50 insertions, 15 deletions

diff --git a/unpacker/unpacker.go b/unpacker/unpacker.go
index 6aa0f36..c7e7099 100644
--- a/unpacker/unpacker.go
+++ b/unpacker/unpacker.go
@@ -5,12 +5,15 @@ import (
 	"io"
 	"os"
 	"path/filepath"
+	"regexp"
 
 	"github.com/mpolden/sfv"
 	"github.com/nwaples/rardecode"
 	"github.com/pkg/errors"
 )
 
+var rarPartRE = regexp.MustCompile(`\.part0*(\d+)\.rar$`)
+
 type unpacker struct {
 	SFV  *sfv.SFV
 	Dir  string
@@ -22,7 +25,7 @@ func New(dir string) (*unpacker, error) {
 	if err != nil {
 		return nil, err
 	}
-	rar, err := findRAR(sfv)
+	rar, err := findFirstRAR(sfv)
 	if err != nil {
 		return nil, err
 	}
@@ -33,13 +36,19 @@ func New(dir string) (*unpacker, error) {
 	}, nil
 }
 
-func isRAR(name string) bool {
-	return filepath.Ext(name) == ".rar"
+func isRAR(name string) bool { return filepath.Ext(name) == ".rar" }
+
+func isFirstRAR(name string) bool {
+	m := rarPartRE.FindStringSubmatch(name)
+	if len(m) == 2 {
+		return m[1] == "1"
+	}
+	return isRAR(name)
 }
 
-func findRAR(s *sfv.SFV) (string, error) {
+func findFirstRAR(s *sfv.SFV) (string, error) {
 	for _, c := range s.Checksums {
-		if isRAR(c.Path) {
+		if isFirstRAR(c.Path) {
 			return c.Path, nil
 		}
 	}
diff --git a/unpacker/unpacker_test.go b/unpacker/unpacker_test.go
index 25fa3c0..3f0e3ee 100644
--- a/unpacker/unpacker_test.go
+++ b/unpacker/unpacker_test.go
@@ -9,17 +9,43 @@ import (
 	"github.com/mpolden/sfv"
 )
 
-func TestFindRAR(t *testing.T) {
-	sfv := &sfv.SFV{Checksums: []sfv.Checksum{
-		sfv.Checksum{Path: "foo.r00"},
-		sfv.Checksum{Path: "foo.rar"},
-	}}
-	archive, err := findRAR(sfv)
-	if err != nil {
-		t.Fatal(err)
+func TestFindFirstRAR(t *testing.T) {
+	var tests = []struct {
+		sfv      *sfv.SFV
+		firstRAR string
+	}{
+		{&sfv.SFV{Checksums: []sfv.Checksum{
+			{Path: "foo.r00"},
+			{Path: "foo.rar"},
+			{Path: "foo.r01"},
+		}}, "foo.rar"},
+		{&sfv.SFV{Checksums: []sfv.Checksum{
+			{Path: "foo.part3.rar"},
+			{Path: "foo.part2.rar"},
+			{Path: "foo.part1.rar"},
+		}}, "foo.part1.rar"},
+		{&sfv.SFV{Checksums: []sfv.Checksum{
+			{Path: "foo.part03.rar"},
+			{Path: "foo.part01.rar"},
+			{Path: "foo.part10.rar"},
+			{Path: "foo.part02.rar"},
+		}}, "foo.part01.rar"},
+		{&sfv.SFV{Checksums: []sfv.Checksum{
+			{Path: "foo.part003.rar"},
+			{Path: "foo.part100.rar"},
+			{Path: "foo.part001.rar"},
+			{Path: "foo.part002.rar"},
+		}}, "foo.part001.rar"},
 	}
-	if want := "foo.rar"; archive != want {
-		t.Errorf("want %q, got %q", want, archive)
+
+	for i, tt := range tests {
+		got, err := findFirstRAR(tt.sfv)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if want := tt.firstRAR; want != got {
+			t.Errorf("#%d: want %q, got %q", i, want, got)
+		}
 	}
 }