New UI merge in progress

17 files changed, 1124 insertions, 0 deletions

diff --git a/modules/git/blob.go b/modules/git/blob.go
new file mode 100644
index 0000000000..3ce462a3c2
--- /dev/null
+++ b/modules/git/blob.go
@@ -0,0 +1,26 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"bytes"
+	"errors"
+	"io"
+
+	"github.com/Unknwon/com"
+)
+
+type Blob struct {
+	repo *Repository
+	*TreeEntry
+}
+
+func (b *Blob) Data() (io.Reader, error) {
+	stdout, stderr, err := com.ExecCmdDirBytes(b.repo.Path, "git", "show", b.Id.String())
+	if err != nil {
+		return nil, errors.New(string(stderr))
+	}
+	return bytes.NewBuffer(stdout), nil
+}
diff --git a/modules/git/commit.go b/modules/git/commit.go
new file mode 100644
index 0000000000..f61f2927b9
--- /dev/null
+++ b/modules/git/commit.go
@@ -0,0 +1,78 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"container/list"
+	"strings"
+)
+
+// Commit represents a git commit.
+type Commit struct {
+	Tree
+	Id            sha1 // The id of this commit object
+	Author        *Signature
+	Committer     *Signature
+	CommitMessage string
+
+	parents []sha1 // sha1 strings
+}
+
+// Return the commit message. Same as retrieving CommitMessage directly.
+func (c *Commit) Message() string {
+	return c.CommitMessage
+}
+
+func (c *Commit) Summary() string {
+	return strings.Split(c.CommitMessage, "\n")[0]
+}
+
+// Return oid of the parent number n (0-based index). Return nil if no such parent exists.
+func (c *Commit) ParentId(n int) (id sha1, err error) {
+	if n >= len(c.parents) {
+		err = IdNotExist
+		return
+	}
+	return c.parents[n], nil
+}
+
+// Return parent number n (0-based index)
+func (c *Commit) Parent(n int) (*Commit, error) {
+	id, err := c.ParentId(n)
+	if err != nil {
+		return nil, err
+	}
+	parent, err := c.repo.getCommit(id)
+	if err != nil {
+		return nil, err
+	}
+	return parent, nil
+}
+
+// Return the number of parents of the commit. 0 if this is the
+// root commit, otherwise 1,2,...
+func (c *Commit) ParentCount() int {
+	return len(c.parents)
+}
+
+func (c *Commit) CommitsBefore() (*list.List, error) {
+	return c.repo.getCommitsBefore(c.Id)
+}
+
+func (c *Commit) CommitsBeforeUntil(commitId string) (*list.List, error) {
+	ec, err := c.repo.GetCommit(commitId)
+	if err != nil {
+		return nil, err
+	}
+	return c.repo.CommitsBetween(c, ec)
+}
+
+func (c *Commit) CommitsCount() (int, error) {
+	return c.repo.commitsCount(c.Id)
+}
+
+func (c *Commit) GetCommitOfRelPath(relPath string) (*Commit, error) {
+	return c.repo.getCommitOfRelPath(c.Id, relPath)
+}
diff --git a/modules/git/commit_archive.go b/modules/git/commit_archive.go
new file mode 100644
index 0000000000..23b4b058dd
--- /dev/null
+++ b/modules/git/commit_archive.go
@@ -0,0 +1,36 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"fmt"
+
+	"github.com/Unknwon/com"
+)
+
+type ArchiveType int
+
+const (
+	ZIP ArchiveType = iota + 1
+	TARGZ
+)
+
+func (c *Commit) CreateArchive(path string, archiveType ArchiveType) error {
+	var format string
+	switch archiveType {
+	case ZIP:
+		format = "zip"
+	case TARGZ:
+		format = "tar.gz"
+	default:
+		return fmt.Errorf("unknown format: %v", archiveType)
+	}
+
+	_, stderr, err := com.ExecCmdDir(c.repo.Path, "git", "archive", "--format="+format, "-o", path, c.Id.String())
+	if err != nil {
+		return fmt.Errorf("%s", stderr)
+	}
+	return nil
+}
diff --git a/modules/git/repo.go b/modules/git/repo.go
new file mode 100644
index 0000000000..14ac39a3ed
--- /dev/null
+++ b/modules/git/repo.go
@@ -0,0 +1,27 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"path/filepath"
+)
+
+// Repository represents a Git repository.
+type Repository struct {
+	Path string
+
+	commitCache map[sha1]*Commit
+	tagCache    map[sha1]*Tag
+}
+
+// OpenRepository opens the repository at the given path.
+func OpenRepository(repoPath string) (*Repository, error) {
+	repoPath, err := filepath.Abs(repoPath)
+	if err != nil {
+		return nil, err
+	}
+
+	return &Repository{Path: repoPath}, nil
+}
diff --git a/modules/git/repo_branch.go b/modules/git/repo_branch.go
new file mode 100644
index 0000000000..726019c1b1
--- /dev/null
+++ b/modules/git/repo_branch.go
@@ -0,0 +1,38 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"errors"
+	"strings"
+
+	"github.com/Unknwon/com"
+)
+
+func IsBranchExist(repoPath, branchName string) bool {
+	_, _, err := com.ExecCmdDir(repoPath, "git", "show-ref", "--verify", "refs/heads/"+branchName)
+	return err == nil
+}
+
+func (repo *Repository) IsBranchExist(branchName string) bool {
+	return IsBranchExist(repo.Path, branchName)
+}
+
+func (repo *Repository) GetBranches() ([]string, error) {
+	stdout, stderr, err := com.ExecCmdDir(repo.Path, "git", "show-ref", "--heads")
+	if err != nil {
+		return nil, errors.New(stderr)
+	}
+	infos := strings.Split(stdout, "\n")
+	branches := make([]string, len(infos)-1)
+	for i, info := range infos[:len(infos)-1] {
+		parts := strings.Split(info, " ")
+		if len(parts) != 2 {
+			continue // NOTE: I should believe git will not give me wrong string.
+		}
+		branches[i] = strings.TrimPrefix(parts[1], "refs/heads/")
+	}
+	return branches, nil
+}
diff --git a/modules/git/repo_commit.go b/modules/git/repo_commit.go
new file mode 100644
index 0000000000..b1ea5a29a5
--- /dev/null
+++ b/modules/git/repo_commit.go
@@ -0,0 +1,234 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"bytes"
+	"container/list"
+	"errors"
+	"strings"
+	"sync"
+
+	"github.com/Unknwon/com"
+)
+
+func (repo *Repository) getCommitIdOfRef(refpath string) (string, error) {
+	stdout, stderr, err := com.ExecCmdDir(repo.Path, "git", "show-ref", "--verify", refpath)
+	if err != nil {
+		return "", errors.New(stderr)
+	}
+	return strings.Split(stdout, " ")[0], nil
+}
+
+func (repo *Repository) GetCommitIdOfBranch(branchName string) (string, error) {
+	return repo.getCommitIdOfRef("refs/heads/" + branchName)
+}
+
+// get branch's last commit or a special commit by id string
+func (repo *Repository) GetCommitOfBranch(branchName string) (*Commit, error) {
+	commitId, err := repo.GetCommitIdOfBranch(branchName)
+	if err != nil {
+		return nil, err
+	}
+
+	return repo.GetCommit(commitId)
+}
+
+// Parse commit information from the (uncompressed) raw
+// data from the commit object.
+// \n\n separate headers from message
+func parseCommitData(data []byte) (*Commit, error) {
+	commit := new(Commit)
+	commit.parents = make([]sha1, 0, 1)
+	// we now have the contents of the commit object. Let's investigate...
+	nextline := 0
+l:
+	for {
+		eol := bytes.IndexByte(data[nextline:], '\n')
+		switch {
+		case eol > 0:
+			line := data[nextline : nextline+eol]
+			spacepos := bytes.IndexByte(line, ' ')
+			reftype := line[:spacepos]
+			switch string(reftype) {
+			case "tree":
+				id, err := NewIdFromString(string(line[spacepos+1:]))
+				if err != nil {
+					return nil, err
+				}
+				commit.Tree.Id = id
+			case "parent":
+				// A commit can have one or more parents
+				oid, err := NewIdFromString(string(line[spacepos+1:]))
+				if err != nil {
+					return nil, err
+				}
+				commit.parents = append(commit.parents, oid)
+			case "author":
+				sig, err := newSignatureFromCommitline(line[spacepos+1:])
+				if err != nil {
+					return nil, err
+				}
+				commit.Author = sig
+			case "committer":
+				sig, err := newSignatureFromCommitline(line[spacepos+1:])
+				if err != nil {
+					return nil, err
+				}
+				commit.Committer = sig
+			}
+			nextline += eol + 1
+		case eol == 0:
+			commit.CommitMessage = string(data[nextline+1:])
+			break l
+		default:
+			break l
+		}
+	}
+	return commit, nil
+}
+
+func (repo *Repository) getCommit(id sha1) (*Commit, error) {
+	if repo.commitCache != nil {
+		if c, ok := repo.commitCache[id]; ok {
+			return c, nil
+		}
+	} else {
+		repo.commitCache = make(map[sha1]*Commit, 10)
+	}
+
+	data, bytErr, err := com.ExecCmdDirBytes(repo.Path, "git", "cat-file", "-p", id.String())
+	if err != nil {
+		return nil, errors.New(string(bytErr))
+	}
+
+	commit, err := parseCommitData(data)
+	if err != nil {
+		return nil, err
+	}
+	commit.repo = repo
+	commit.Id = id
+
+	repo.commitCache[id] = commit
+	return commit, nil
+}
+
+// Find the commit object in the repository.
+func (repo *Repository) GetCommit(commitId string) (*Commit, error) {
+	id, err := NewIdFromString(commitId)
+	if err != nil {
+		return nil, err
+	}
+
+	return repo.getCommit(id)
+}
+
+func (repo *Repository) commitsCount(id sha1) (int, error) {
+	stdout, stderr, err := com.ExecCmdDir(repo.Path, "git", "rev-list", "--count", id.String())
+	if err != nil {
+		return 0, errors.New(stderr)
+	}
+	return com.StrTo(strings.TrimSpace(stdout)).Int()
+}
+
+// used only for single tree, (]
+func (repo *Repository) CommitsBetween(last *Commit, before *Commit) (*list.List, error) {
+	l := list.New()
+	if last == nil || last.ParentCount() == 0 {
+		return l, nil
+	}
+
+	var err error
+	cur := last
+	for {
+		if cur.Id.Equal(before.Id) {
+			break
+		}
+		l.PushBack(cur)
+		if cur.ParentCount() == 0 {
+			break
+		}
+		cur, err = cur.Parent(0)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return l, nil
+}
+
+func (repo *Repository) commitsBefore(lock *sync.Mutex, l *list.List, parent *list.Element, id sha1, limit int) error {
+	commit, err := repo.getCommit(id)
+	if err != nil {
+		return err
+	}
+
+	var e *list.Element
+	if parent == nil {
+		e = l.PushBack(commit)
+	} else {
+		var in = parent
+		for {
+			if in == nil {
+				break
+			} else if in.Value.(*Commit).Id.Equal(commit.Id) {
+				return nil
+			} else {
+				if in.Next() == nil {
+					break
+				}
+				if in.Value.(*Commit).Committer.When.Equal(commit.Committer.When) {
+					break
+				}
+
+				if in.Value.(*Commit).Committer.When.After(commit.Committer.When) &&
+					in.Next().Value.(*Commit).Committer.When.Before(commit.Committer.When) {
+					break
+				}
+			}
+			in = in.Next()
+		}
+
+		e = l.InsertAfter(commit, in)
+	}
+
+	var pr = parent
+	if commit.ParentCount() > 1 {
+		pr = e
+	}
+
+	for i := 0; i < commit.ParentCount(); i++ {
+		id, err := commit.ParentId(i)
+		if err != nil {
+			return err
+		}
+		err = repo.commitsBefore(lock, l, pr, id, 0)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (repo *Repository) getCommitsBefore(id sha1) (*list.List, error) {
+	l := list.New()
+	lock := new(sync.Mutex)
+	err := repo.commitsBefore(lock, l, nil, id, 0)
+	return l, err
+}
+
+func (repo *Repository) getCommitOfRelPath(id sha1, relPath string) (*Commit, error) {
+	stdout, _, err := com.ExecCmdDir(repo.Path, "git", "log", "-1", prettyLogFormat, id.String(), "--", relPath)
+	if err != nil {
+		return nil, err
+	}
+
+	id, err = NewIdFromString(string(stdout))
+	if err != nil {
+		return nil, err
+	}
+
+	return repo.getCommit(id)
+}
diff --git a/modules/git/repo_object.go b/modules/git/repo_object.go
new file mode 100644
index 0000000000..da79f2c731
--- /dev/null
+++ b/modules/git/repo_object.go
@@ -0,0 +1,14 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+type ObjectType string
+
+const (
+	COMMIT ObjectType = "commit"
+	TREE   ObjectType = "tree"
+	BLOB   ObjectType = "blob"
+	TAG    ObjectType = "tag"
+)
diff --git a/modules/git/repo_tag.go b/modules/git/repo_tag.go
new file mode 100644
index 0000000000..cefbe783ab
--- /dev/null
+++ b/modules/git/repo_tag.go
@@ -0,0 +1,96 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"errors"
+	"strings"
+
+	"github.com/Unknwon/com"
+)
+
+func IsTagExist(repoPath, tagName string) bool {
+	_, _, err := com.ExecCmdDir(repoPath, "git", "show-ref", "--verify", "refs/tags/"+tagName)
+	return err == nil
+}
+
+func (repo *Repository) IsTagExist(tagName string) bool {
+	return IsTagExist(repo.Path, tagName)
+}
+
+// GetTags returns all tags of given repository.
+func (repo *Repository) GetTags() ([]string, error) {
+	stdout, stderr, err := com.ExecCmdDir(repo.Path, "git", "tag", "-l")
+	if err != nil {
+		return nil, errors.New(stderr)
+	}
+	tags := strings.Split(stdout, "\n")
+	return tags[:len(tags)-1], nil
+}
+
+func (repo *Repository) getTag(id sha1) (*Tag, error) {
+	if repo.tagCache != nil {
+		if t, ok := repo.tagCache[id]; ok {
+			return t, nil
+		}
+	} else {
+		repo.tagCache = make(map[sha1]*Tag, 10)
+	}
+
+	// Get tag type.
+	tp, stderr, err := com.ExecCmdDir(repo.Path, "git", "cat-file", "-t", id.String())
+	if err != nil {
+		return nil, errors.New(stderr)
+	}
+
+	// Tag is a commit.
+	if ObjectType(tp) == COMMIT {
+		tag := &Tag{
+			Id:     id,
+			Object: id,
+			Type:   string(COMMIT),
+			repo:   repo,
+		}
+		repo.tagCache[id] = tag
+		return tag, nil
+	}
+
+	// Tag with message.
+	data, bytErr, err := com.ExecCmdDirBytes(repo.Path, "git", "cat-file", "-p", id.String())
+	if err != nil {
+		return nil, errors.New(string(bytErr))
+	}
+
+	tag, err := parseTagData(data)
+	if err != nil {
+		return nil, err
+	}
+
+	tag.Id = id
+	tag.repo = repo
+
+	repo.tagCache[id] = tag
+	return tag, nil
+}
+
+// GetTag returns a Git tag by given name.
+func (repo *Repository) GetTag(tagName string) (*Tag, error) {
+	stdout, stderr, err := com.ExecCmdDir(repo.Path, "git", "show-ref", "--tags", tagName)
+	if err != nil {
+		return nil, errors.New(stderr)
+	}
+
+	id, err := NewIdFromString(strings.Split(stdout, " ")[0])
+	if err != nil {
+		return nil, err
+	}
+
+	tag, err := repo.getTag(id)
+	if err != nil {
+		return nil, err
+	}
+	tag.Name = tagName
+	return tag, nil
+}
diff --git a/modules/git/repo_tree.go b/modules/git/repo_tree.go
new file mode 100644
index 0000000000..da394c3605
--- /dev/null
+++ b/modules/git/repo_tree.go
@@ -0,0 +1,32 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"fmt"
+
+	"github.com/Unknwon/com"
+)
+
+// Find the tree object in the repository.
+func (repo *Repository) GetTree(idStr string) (*Tree, error) {
+	id, err := NewIdFromString(idStr)
+	if err != nil {
+		return nil, err
+	}
+	return repo.getTree(id)
+}
+
+func (repo *Repository) getTree(id sha1) (*Tree, error) {
+	treePath := filepathFromSHA1(repo.Path, id.String())
+	if !com.IsFile(treePath) {
+		_, _, err := com.ExecCmdDir(repo.Path, "git", "ls-tree", id.String())
+		if err != nil {
+			return nil, fmt.Errorf("repo.getTree: %v", ErrNotExist)
+		}
+	}
+
+	return NewTree(repo, id), nil
+}
diff --git a/modules/git/sha1.go b/modules/git/sha1.go
new file mode 100644
index 0000000000..5c57e89b6a
--- /dev/null
+++ b/modules/git/sha1.go
@@ -0,0 +1,87 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"strings"
+)
+
+var (
+	IdNotExist = errors.New("sha1 id not exist")
+)
+
+type sha1 [20]byte
+
+// Return true if s has the same sha1 as caller.
+// Support 40-length-string, []byte, sha1
+func (id sha1) Equal(s2 interface{}) bool {
+	switch v := s2.(type) {
+	case string:
+		if len(v) != 40 {
+			return false
+		}
+		return v == id.String()
+	case []byte:
+		if len(v) != 20 {
+			return false
+		}
+		for i, v := range v {
+			if id[i] != v {
+				return false
+			}
+		}
+	case sha1:
+		for i, v := range v {
+			if id[i] != v {
+				return false
+			}
+		}
+	default:
+		return false
+	}
+	return true
+}
+
+// Return string (hex) representation of the Oid
+func (s sha1) String() string {
+	result := make([]byte, 0, 40)
+	hexvalues := []byte("0123456789abcdef")
+	for i := 0; i < 20; i++ {
+		result = append(result, hexvalues[s[i]>>4])
+		result = append(result, hexvalues[s[i]&0xf])
+	}
+	return string(result)
+}
+
+// Create a new sha1 from a 20 byte slice.
+func NewId(b []byte) (sha1, error) {
+	var id sha1
+	if len(b) != 20 {
+		return id, errors.New("Length must be 20")
+	}
+
+	for i := 0; i < 20; i++ {
+		id[i] = b[i]
+	}
+	return id, nil
+}
+
+// Create a new sha1 from a Sha1 string of length 40.
+func NewIdFromString(s string) (sha1, error) {
+	s = strings.TrimSpace(s)
+	var id sha1
+	if len(s) != 40 {
+		return id, fmt.Errorf("Length must be 40")
+	}
+	b, err := hex.DecodeString(s)
+	if err != nil {
+		return id, err
+	}
+
+	return NewId(b)
+}
diff --git a/modules/git/signature.go b/modules/git/signature.go
new file mode 100644
index 0000000000..20f647d266
--- /dev/null
+++ b/modules/git/signature.go
@@ -0,0 +1,40 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"bytes"
+	"strconv"
+	"time"
+)
+
+// Author and Committer information
+type Signature struct {
+	Email string
+	Name  string
+	When  time.Time
+}
+
+// Helper to get a signature from the commit line, which looks like this:
+//     author Patrick Gundlach <gundlach@speedata.de> 1378823654 +0200
+// but without the "author " at the beginning (this method should)
+// be used for author and committer.
+//
+// FIXME: include timezone!
+func newSignatureFromCommitline(line []byte) (*Signature, error) {
+	sig := new(Signature)
+	emailstart := bytes.IndexByte(line, '<')
+	sig.Name = string(line[:emailstart-1])
+	emailstop := bytes.IndexByte(line, '>')
+	sig.Email = string(line[emailstart+1 : emailstop])
+	timestop := bytes.IndexByte(line[emailstop+2:], ' ')
+	timestring := string(line[emailstop+2 : emailstop+2+timestop])
+	seconds, err := strconv.ParseInt(timestring, 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	sig.When = time.Unix(seconds, 0)
+	return sig, nil
+}
diff --git a/modules/git/tag.go b/modules/git/tag.go
new file mode 100644
index 0000000000..7fbbcb1cbf
--- /dev/null
+++ b/modules/git/tag.go
@@ -0,0 +1,67 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"bytes"
+)
+
+// Tag represents a Git tag.
+type Tag struct {
+	Name       string
+	Id         sha1
+	repo       *Repository
+	Object     sha1 // The id of this commit object
+	Type       string
+	Tagger     *Signature
+	TagMessage string
+}
+
+func (tag *Tag) Commit() (*Commit, error) {
+	return tag.repo.getCommit(tag.Object)
+}
+
+// Parse commit information from the (uncompressed) raw
+// data from the commit object.
+// \n\n separate headers from message
+func parseTagData(data []byte) (*Tag, error) {
+	tag := new(Tag)
+	// we now have the contents of the commit object. Let's investigate...
+	nextline := 0
+l:
+	for {
+		eol := bytes.IndexByte(data[nextline:], '\n')
+		switch {
+		case eol > 0:
+			line := data[nextline : nextline+eol]
+			spacepos := bytes.IndexByte(line, ' ')
+			reftype := line[:spacepos]
+			switch string(reftype) {
+			case "object":
+				id, err := NewIdFromString(string(line[spacepos+1:]))
+				if err != nil {
+					return nil, err
+				}
+				tag.Object = id
+			case "type":
+				// A commit can have one or more parents
+				tag.Type = string(line[spacepos+1:])
+			case "tagger":
+				sig, err := newSignatureFromCommitline(line[spacepos+1:])
+				if err != nil {
+					return nil, err
+				}
+				tag.Tagger = sig
+			}
+			nextline += eol + 1
+		case eol == 0:
+			tag.TagMessage = string(data[nextline+1:])
+			break l
+		default:
+			break l
+		}
+	}
+	return tag, nil
+}
diff --git a/modules/git/tree.go b/modules/git/tree.go
new file mode 100644
index 0000000000..03152c34ac
--- /dev/null
+++ b/modules/git/tree.go
@@ -0,0 +1,124 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"bytes"
+	"errors"
+	"strings"
+
+	"github.com/Unknwon/com"
+)
+
+var (
+	ErrNotExist = errors.New("error not exist")
+)
+
+// A tree is a flat directory listing.
+type Tree struct {
+	Id   sha1
+	repo *Repository
+
+	// parent tree
+	ptree *Tree
+
+	entries       Entries
+	entriesParsed bool
+}
+
+// Parse tree information from the (uncompressed) raw
+// data from the tree object.
+func parseTreeData(tree *Tree, data []byte) ([]*TreeEntry, error) {
+	entries := make([]*TreeEntry, 0, 10)
+	l := len(data)
+	pos := 0
+	for pos < l {
+		entry := new(TreeEntry)
+		entry.ptree = tree
+		step := 6
+		switch string(data[pos : pos+step]) {
+		case "100644":
+			entry.mode = ModeBlob
+			entry.Type = BLOB
+		case "100755":
+			entry.mode = ModeExec
+			entry.Type = BLOB
+		case "120000":
+			entry.mode = ModeSymlink
+			entry.Type = BLOB
+		case "160000":
+			entry.mode = ModeCommit
+			entry.Type = COMMIT
+		case "040000":
+			entry.mode = ModeTree
+			entry.Type = TREE
+		default:
+			return nil, errors.New("unknown type: " + string(data[pos:pos+step]))
+		}
+		pos += step + 6 // Skip string type of entry type.
+
+		step = 40
+		id, err := NewIdFromString(string(data[pos : pos+step]))
+		if err != nil {
+			return nil, err
+		}
+		entry.Id = id
+		pos += step + 1 // Skip half of sha1.
+
+		step = bytes.IndexByte(data[pos:], '\n')
+		entry.name = string(data[pos : pos+step])
+		pos += step + 1
+		entries = append(entries, entry)
+	}
+	return entries, nil
+}
+
+func (t *Tree) SubTree(rpath string) (*Tree, error) {
+	if len(rpath) == 0 {
+		return t, nil
+	}
+
+	paths := strings.Split(rpath, "/")
+	var err error
+	var g = t
+	var p = t
+	var te *TreeEntry
+	for _, name := range paths {
+		te, err = p.GetTreeEntryByPath(name)
+		if err != nil {
+			return nil, err
+		}
+
+		g, err = t.repo.getTree(te.Id)
+		if err != nil {
+			return nil, err
+		}
+		g.ptree = p
+		p = g
+	}
+	return g, nil
+}
+
+func (t *Tree) ListEntries(relpath string) (Entries, error) {
+	if t.entriesParsed {
+		return t.entries, nil
+	}
+	t.entriesParsed = true
+
+	stdout, _, err := com.ExecCmdDirBytes(t.repo.Path,
+		"git", "ls-tree", t.Id.String())
+	if err != nil {
+		return nil, err
+	}
+	t.entries, err = parseTreeData(t, stdout)
+	return t.entries, err
+}
+
+func NewTree(repo *Repository, id sha1) *Tree {
+	tree := new(Tree)
+	tree.Id = id
+	tree.repo = repo
+	return tree
+}
diff --git a/modules/git/tree_blob.go b/modules/git/tree_blob.go
new file mode 100644
index 0000000000..debc722bc9
--- /dev/null
+++ b/modules/git/tree_blob.go
@@ -0,0 +1,46 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"fmt"
+	"path"
+	"strings"
+)
+
+func (t *Tree) GetTreeEntryByPath(relpath string) (*TreeEntry, error) {
+	if len(relpath) == 0 {
+		return &TreeEntry{
+			Id:   t.Id,
+			Type: TREE,
+			mode: ModeTree,
+		}, nil
+		// return nil, fmt.Errorf("GetTreeEntryByPath(empty relpath): %v", ErrNotExist)
+	}
+
+	relpath = path.Clean(relpath)
+	parts := strings.Split(relpath, "/")
+	var err error
+	tree := t
+	for i, name := range parts {
+		if i == len(parts)-1 {
+			entries, err := tree.ListEntries(path.Dir(relpath))
+			if err != nil {
+				return nil, err
+			}
+			for _, v := range entries {
+				if v.name == name {
+					return v, nil
+				}
+			}
+		} else {
+			tree, err = tree.SubTree(name)
+			if err != nil {
+				return nil, err
+			}
+		}
+	}
+	return nil, fmt.Errorf("GetTreeEntryByPath: %v", ErrNotExist)
+}
diff --git a/modules/git/tree_entry.go b/modules/git/tree_entry.go
new file mode 100644
index 0000000000..e842f2332a
--- /dev/null
+++ b/modules/git/tree_entry.go
@@ -0,0 +1,109 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"sort"
+	"strings"
+
+	"github.com/Unknwon/com"
+)
+
+type EntryMode int
+
+// There are only a few file modes in Git. They look like unix file modes, but they can only be
+// one of these.
+const (
+	ModeBlob    EntryMode = 0100644
+	ModeExec    EntryMode = 0100755
+	ModeSymlink EntryMode = 0120000
+	ModeCommit  EntryMode = 0160000
+	ModeTree    EntryMode = 0040000
+)
+
+type TreeEntry struct {
+	Id   sha1
+	Type ObjectType
+
+	mode EntryMode
+	name string
+
+	ptree *Tree
+
+	commited bool
+
+	size  int64
+	sized bool
+}
+
+func (te *TreeEntry) Name() string {
+	return te.name
+}
+
+func (te *TreeEntry) Size() int64 {
+	if te.IsDir() {
+		return 0
+	}
+
+	if te.sized {
+		return te.size
+	}
+
+	stdout, _, err := com.ExecCmdDir(te.ptree.repo.Path, "git", "cat-file", "-s", te.Id.String())
+	if err != nil {
+		return 0
+	}
+
+	te.sized = true
+	te.size = com.StrTo(strings.TrimSpace(stdout)).MustInt64()
+	return te.size
+}
+
+func (te *TreeEntry) IsDir() bool {
+	return te.mode == ModeTree
+}
+
+func (te *TreeEntry) EntryMode() EntryMode {
+	return te.mode
+}
+
+func (te *TreeEntry) Blob() *Blob {
+	return &Blob{
+		repo:      te.ptree.repo,
+		TreeEntry: te,
+	}
+}
+
+type Entries []*TreeEntry
+
+var sorter = []func(t1, t2 *TreeEntry) bool{
+	func(t1, t2 *TreeEntry) bool {
+		return t1.IsDir() && !t2.IsDir()
+	},
+	func(t1, t2 *TreeEntry) bool {
+		return t1.name < t2.name
+	},
+}
+
+func (bs Entries) Len() int      { return len(bs) }
+func (bs Entries) Swap(i, j int) { bs[i], bs[j] = bs[j], bs[i] }
+func (bs Entries) Less(i, j int) bool {
+	t1, t2 := bs[i], bs[j]
+	var k int
+	for k = 0; k < len(sorter)-1; k++ {
+		sort := sorter[k]
+		switch {
+		case sort(t1, t2):
+			return true
+		case sort(t2, t1):
+			return false
+		}
+	}
+	return sorter[k](t1, t2)
+}
+
+func (bs Entries) Sort() {
+	sort.Sort(bs)
+}
diff --git a/modules/git/utils.go b/modules/git/utils.go
new file mode 100644
index 0000000000..3c0c60f235
--- /dev/null
+++ b/modules/git/utils.go
@@ -0,0 +1,27 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"path/filepath"
+	"strings"
+)
+
+const prettyLogFormat = `--pretty=format:%H`
+
+func RefEndName(refStr string) string {
+	index := strings.LastIndex(refStr, "/")
+	if index != -1 {
+		return refStr[index+1:]
+	}
+	return refStr
+}
+
+// If the object is stored in its own file (i.e not in a pack file),
+// this function returns the full path to the object file.
+// It does not test if the file exists.
+func filepathFromSHA1(rootdir, sha1 string) string {
+	return filepath.Join(rootdir, "objects", sha1[:2], sha1[2:])
+}
diff --git a/modules/git/version.go b/modules/git/version.go
new file mode 100644
index 0000000000..683e859b47
--- /dev/null
+++ b/modules/git/version.go
@@ -0,0 +1,43 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package git
+
+import (
+	"errors"
+	"strings"
+
+	"github.com/Unknwon/com"
+)
+
+// Version represents version of Git.
+type Version struct {
+	Major, Minor, Patch int
+}
+
+// GetVersion returns current Git version installed.
+func GetVersion() (Version, error) {
+	stdout, stderr, err := com.ExecCmd("git", "version")
+	if err != nil {
+		return Version{}, errors.New(stderr)
+	}
+
+	infos := strings.Split(stdout, " ")
+	if len(infos) < 3 {
+		return Version{}, errors.New("not enough output")
+	}
+
+	v := Version{}
+	for i, s := range strings.Split(strings.TrimSpace(infos[2]), ".") {
+		switch i {
+		case 0:
+			v.Major, _ = com.StrTo(s).Int()
+		case 1:
+			v.Minor, _ = com.StrTo(s).Int()
+		case 2:
+			v.Patch, _ = com.StrTo(s).Int()
+		}
+	}
+	return v, nil
+}