1 files changed, 137 insertions, 0 deletions
diff --git a/cache/bug_cache.go b/cache/bug_cache.go
new file mode 100644
index 00000000..59c39f5c
--- /dev/null
+++ b/cache/bug_cache.go
@@ -0,0 +1,137 @@
+package cache
+
+import (
+	"github.com/MichaelMure/git-bug/bug"
+	"github.com/MichaelMure/git-bug/bug/operations"
+	"github.com/MichaelMure/git-bug/repository"
+	"github.com/MichaelMure/git-bug/util"
+)
+
+type BugCacher interface {
+	Snapshot() *bug.Snapshot
+	ClearSnapshot()
+
+	// Mutations
+	AddComment(message string) error
+	AddCommentWithFiles(message string, files []util.Hash) error
+	ChangeLabels(added []string, removed []string) error
+	Open() error
+	Close() error
+	SetTitle(title string) error
+
+	Commit() error
+	CommitAsNeeded() error
+}
+
+type BugCache struct {
+	repo repository.Repo
+	bug  *bug.Bug
+	snap *bug.Snapshot
+}
+
+func NewBugCache(repo repository.Repo, b *bug.Bug) BugCacher {
+	return &BugCache{
+		repo: repo,
+		bug:  b,
+	}
+}
+
+func (c *BugCache) Snapshot() *bug.Snapshot {
+	if c.snap == nil {
+		snap := c.bug.Compile()
+		c.snap = &snap
+	}
+	return c.snap
+}
+
+func (c *BugCache) ClearSnapshot() {
+	c.snap = nil
+}
+
+func (c *BugCache) AddComment(message string) error {
+	return c.AddCommentWithFiles(message, nil)
+}
+
+func (c *BugCache) AddCommentWithFiles(message string, files []util.Hash) error {
+	author, err := bug.GetUser(c.repo)
+	if err != nil {
+		return err
+	}
+
+	operations.CommentWithFiles(c.bug, author, message, files)
+
+	// TODO: perf --> the snapshot could simply be updated with the new op
+	c.ClearSnapshot()
+
+	return nil
+}
+
+func (c *BugCache) ChangeLabels(added []string, removed []string) error {
+	author, err := bug.GetUser(c.repo)
+	if err != nil {
+		return err
+	}
+
+	err = operations.ChangeLabels(nil, c.bug, author, added, removed)
+	if err != nil {
+		return err
+	}
+
+	// TODO: perf --> the snapshot could simply be updated with the new op
+	c.ClearSnapshot()
+
+	return nil
+}
+
+func (c *BugCache) Open() error {
+	author, err := bug.GetUser(c.repo)
+	if err != nil {
+		return err
+	}
+
+	operations.Open(c.bug, author)
+
+	// TODO: perf --> the snapshot could simply be updated with the new op
+	c.ClearSnapshot()
+
+	return nil
+}
+
+func (c *BugCache) Close() error {
+	author, err := bug.GetUser(c.repo)
+	if err != nil {
+		return err
+	}
+
+	operations.Close(c.bug, author)
+
+	// TODO: perf --> the snapshot could simply be updated with the new op
+	c.ClearSnapshot()
+
+	return nil
+}
+
+func (c *BugCache) SetTitle(title string) error {
+	author, err := bug.GetUser(c.repo)
+	if err != nil {
+		return err
+	}
+
+	operations.SetTitle(c.bug, author, title)
+
+	// TODO: perf --> the snapshot could simply be updated with the new op
+	c.ClearSnapshot()
+
+	return nil
+}
+
+func (c *BugCache) Commit() error {
+	return c.bug.Commit(c.repo)
+}
+
+func (c *BugCache) CommitAsNeeded() error {
+	if c.bug.HasPendingOp() {
+		return c.bug.Commit(c.repo)
+	}
+	return nil
+}