WIP identity in git

1 files changed, 285 insertions, 0 deletions

diff --git a/identity/identity.go b/identity/identity.go
new file mode 100644
index 00000000..f65e2a86
--- /dev/null
+++ b/identity/identity.go
@@ -0,0 +1,285 @@
+// Package identity contains the identity data model and low-level related functions
+package identity
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/MichaelMure/git-bug/repository"
+	"github.com/MichaelMure/git-bug/util/git"
+	"github.com/MichaelMure/git-bug/util/lamport"
+)
+
+const identityRefPattern = "refs/identities/"
+const versionEntryName = "version"
+const identityConfigKey = "git-bug.identity"
+
+type Identity struct {
+	id       string
+	Versions []Version
+}
+
+func NewIdentity(name string, email string) (*Identity, error) {
+	return &Identity{
+		Versions: []Version{
+			{
+				Name:  name,
+				Email: email,
+				Nonce: makeNonce(20),
+			},
+		},
+	}, nil
+}
+
+type identityJson struct {
+	Id string `json:"id"`
+}
+
+// TODO: marshal/unmarshal identity + load/write from OpBase
+
+func Read(repo repository.Repo, id string) (*Identity, error) {
+	// Todo
+	return &Identity{}, nil
+}
+
+// NewFromGitUser will query the repository for user detail and
+// build the corresponding Identity
+/*func NewFromGitUser(repo repository.Repo) (*Identity, error) {
+	name, err := repo.GetUserName()
+	if err != nil {
+		return nil, err
+	}
+	if name == "" {
+		return nil, errors.New("User name is not configured in git yet. Please use `git config --global user.name \"John Doe\"`")
+	}
+
+	email, err := repo.GetUserEmail()
+	if err != nil {
+		return nil, err
+	}
+	if email == "" {
+		return nil, errors.New("User name is not configured in git yet. Please use `git config --global user.email johndoe@example.com`")
+	}
+
+	return NewIdentity(name, email)
+}*/
+
+//
+func BuildFromGit(repo repository.Repo) *Identity {
+	version := Version{}
+
+	name, err := repo.GetUserName()
+	if err == nil {
+		version.Name = name
+	}
+
+	email, err := repo.GetUserEmail()
+	if err == nil {
+		version.Email = email
+	}
+
+	return &Identity{
+		Versions: []Version{
+			version,
+		},
+	}
+}
+
+// SetIdentity store the user identity's id in the git config
+func SetIdentity(repo repository.RepoCommon, identity Identity) error {
+	return repo.StoreConfig(identityConfigKey, identity.Id())
+}
+
+// GetIdentity read the current user identity, set with a git config entry
+func GetIdentity(repo repository.Repo) (*Identity, error) {
+	configs, err := repo.ReadConfigs(identityConfigKey)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(configs) == 0 {
+		return nil, fmt.Errorf("no identity set")
+	}
+
+	if len(configs) > 1 {
+		return nil, fmt.Errorf("multiple identity config exist")
+	}
+
+	var id string
+	for _, val := range configs {
+		id = val
+	}
+
+	return Read(repo, id)
+}
+
+func (i *Identity) AddVersion(version Version) {
+	i.Versions = append(i.Versions, version)
+}
+
+func (i *Identity) Commit(repo repository.ClockedRepo) error {
+	// Todo: check for mismatch between memory and commited data
+
+	var lastCommit git.Hash = ""
+
+	for _, v := range i.Versions {
+		if v.commitHash != "" {
+			lastCommit = v.commitHash
+			// ignore already commited versions
+			continue
+		}
+
+		blobHash, err := v.Write(repo)
+		if err != nil {
+			return err
+		}
+
+		// Make a git tree referencing the blob
+		tree := []repository.TreeEntry{
+			{ObjectType: repository.Blob, Hash: blobHash, Name: versionEntryName},
+		}
+
+		treeHash, err := repo.StoreTree(tree)
+		if err != nil {
+			return err
+		}
+
+		var commitHash git.Hash
+		if lastCommit != "" {
+			commitHash, err = repo.StoreCommitWithParent(treeHash, lastCommit)
+		} else {
+			commitHash, err = repo.StoreCommit(treeHash)
+		}
+
+		if err != nil {
+			return err
+		}
+
+		lastCommit = commitHash
+
+		// if it was the first commit, use the commit hash as the Identity id
+		if i.id == "" {
+			i.id = string(commitHash)
+		}
+	}
+
+	if i.id == "" {
+		panic("identity with no id")
+	}
+
+	ref := fmt.Sprintf("%s%s", identityRefPattern, i.id)
+	err := repo.UpdateRef(ref, lastCommit)
+
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// Validate check if the Identity data is valid
+func (i *Identity) Validate() error {
+	lastTime := lamport.Time(0)
+
+	for _, v := range i.Versions {
+		if err := v.Validate(); err != nil {
+			return err
+		}
+
+		if v.Time < lastTime {
+			return fmt.Errorf("non-chronological version (%d --> %d)", lastTime, v.Time)
+		}
+
+		lastTime = v.Time
+	}
+
+	return nil
+}
+
+func (i *Identity) LastVersion() Version {
+	if len(i.Versions) <= 0 {
+		panic("no version at all")
+	}
+
+	return i.Versions[len(i.Versions)-1]
+}
+
+// Id return the Identity identifier
+func (i *Identity) Id() string {
+	if i.id == "" {
+		// simply panic as it would be a coding error
+		// (using an id of an identity not stored yet)
+		panic("no id yet")
+	}
+	return i.id
+}
+
+// Name return the last version of the name
+func (i *Identity) Name() string {
+	return i.LastVersion().Name
+}
+
+// Email return the last version of the email
+func (i *Identity) Email() string {
+	return i.LastVersion().Email
+}
+
+// Login return the last version of the login
+func (i *Identity) Login() string {
+	return i.LastVersion().Login
+}
+
+// Login return the last version of the Avatar URL
+func (i *Identity) AvatarUrl() string {
+	return i.LastVersion().AvatarUrl
+}
+
+// Login return the last version of the valid keys
+func (i *Identity) Keys() []Key {
+	return i.LastVersion().Keys
+}
+
+// IsProtected return true if the chain of git commits started to be signed.
+// If that's the case, only signed commit with a valid key for this identity can be added.
+func (i *Identity) IsProtected() bool {
+	// Todo
+	return false
+}
+
+// ValidKeysAtTime return the set of keys valid at a given lamport time
+func (i *Identity) ValidKeysAtTime(time lamport.Time) []Key {
+	var result []Key
+
+	for _, v := range i.Versions {
+		if v.Time > time {
+			return result
+		}
+
+		result = v.Keys
+	}
+
+	return result
+}
+
+// Match tell is the Identity match the given query string
+func (i *Identity) Match(query string) bool {
+	query = strings.ToLower(query)
+
+	return strings.Contains(strings.ToLower(i.Name()), query) ||
+		strings.Contains(strings.ToLower(i.Login()), query)
+}
+
+// DisplayName return a non-empty string to display, representing the
+// identity, based on the non-empty values.
+func (i *Identity) DisplayName() string {
+	switch {
+	case i.Name() == "" && i.Login() != "":
+		return i.Login()
+	case i.Name() != "" && i.Login() == "":
+		return i.Name()
+	case i.Name() != "" && i.Login() != "":
+		return fmt.Sprintf("%s (%s)", i.Name(), i.Login())
+	}
+
+	panic("invalid person data")
+}