1 files changed, 123 insertions, 3 deletions
diff --git a/config/config.go b/config/config.go
index a2b5012..fc6d84c 100644
--- a/config/config.go
+++ b/config/config.go
@@ -2,8 +2,11 @@
 package config
 
 import (
+	"bytes"
 	"errors"
 	"fmt"
+
+	format "gopkg.in/src-d/go-git.v4/plumbing/format/config"
 )
 
 const (
@@ -27,17 +30,28 @@ var (
 )
 
 // Config contains the repository configuration
+// ftp://www.kernel.org/pub/software/scm/git/docs/git-config.html#FILES
 type Config struct {
+	// Core variables
 	Core struct {
+		// IsBare if true this repository is assumed to be bare and has no
+		// working directory associated with it
 		IsBare bool
 	}
+	// Remote list of repository remotes
 	Remotes map[string]*RemoteConfig
+
+	// contains the raw information of a config file, the main goal is preserve
+	// the parsed information from the original format, to avoid missing
+	// unsupported features.
+	raw *format.Config
 }
 
 // NewConfig returns a new empty Config
 func NewConfig() *Config {
 	return &Config{
 		Remotes: make(map[string]*RemoteConfig, 0),
+		raw:     format.New(),
 	}
 }
 
@@ -56,11 +70,87 @@ func (c *Config) Validate() error {
 	return nil
 }
 
-// RemoteConfig contains the configuration for a given repository
+const (
+	remoteSection = "remote"
+	coreSection   = "core"
+	fetchKey      = "fetch"
+	urlKey        = "url"
+	bareKey       = "bare"
+)
+
+// Unmarshal parses a git-config file and stores it
+func (c *Config) Unmarshal(b []byte) error {
+	r := bytes.NewBuffer(b)
+	d := format.NewDecoder(r)
+
+	c.raw = format.New()
+	if err := d.Decode(c.raw); err != nil {
+		return err
+	}
+
+	c.unmarshalCore()
+	c.unmarshalRemotes()
+	return nil
+}
+
+func (c *Config) unmarshalCore() {
+	s := c.raw.Section(coreSection)
+	if s.Options.Get(bareKey) == "true" {
+		c.Core.IsBare = true
+	}
+}
+
+func (c *Config) unmarshalRemotes() {
+	s := c.raw.Section(remoteSection)
+	for _, sub := range s.Subsections {
+		r := &RemoteConfig{}
+		r.unmarshal(sub)
+
+		c.Remotes[r.Name] = r
+	}
+}
+
+// Marshal returns Config encoded as a git-config file
+func (c *Config) Marshal() ([]byte, error) {
+	c.marshalCore()
+	c.marshalRemotes()
+
+	buf := bytes.NewBuffer(nil)
+	if err := format.NewEncoder(buf).Encode(c.raw); err != nil {
+		return nil, err
+	}
+
+	return buf.Bytes(), nil
+}
+
+func (c *Config) marshalCore() {
+	s := c.raw.Section(coreSection)
+	s.SetOption(bareKey, fmt.Sprintf("%t", c.Core.IsBare))
+}
+
+func (c *Config) marshalRemotes() {
+	s := c.raw.Section(remoteSection)
+	s.Subsections = make(format.Subsections, len(c.Remotes))
+
+	var i int
+	for _, r := range c.Remotes {
+		s.Subsections[i] = r.marshal()
+		i++
+	}
+}
+
+// RemoteConfig contains the configuration for a given remote repository
 type RemoteConfig struct {
-	Name  string
-	URL   string
+	// Name of the remote
+	Name string
+	// URL the URL of a remote repository
+	URL string
+	// Fetch the default set of "refspec" for fetch operation
 	Fetch []RefSpec
+
+	// raw representation of the subsection, filled by marshal or unmarshal are
+	// called
+	raw *format.Subsection
 }
 
 // Validate validate the fields and set the default values
@@ -79,3 +169,33 @@ func (c *RemoteConfig) Validate() error {
 
 	return nil
 }
+
+func (c *RemoteConfig) unmarshal(s *format.Subsection) {
+	c.raw = s
+
+	fetch := []RefSpec{}
+	for _, f := range c.raw.Options.GetAll(fetchKey) {
+		rs := RefSpec(f)
+		if rs.IsValid() {
+			fetch = append(fetch, rs)
+		}
+	}
+
+	c.Name = c.raw.Name
+	c.URL = c.raw.Option(urlKey)
+	c.Fetch = fetch
+}
+
+func (c *RemoteConfig) marshal() *format.Subsection {
+	if c.raw == nil {
+		c.raw = &format.Subsection{}
+	}
+
+	c.raw.Name = c.Name
+	c.raw.SetOption(urlKey, c.URL)
+	for _, rs := range c.Fetch {
+		c.raw.SetOption(fetchKey, rs.String())
+	}
+
+	return c.raw
+}