1package bug
 2
 3import "github.com/MichaelMure/git-bug/repository"
 4
 5var _ Interface = &WithSnapshot{}
 6
 7// WithSnapshot encapsulate a Bug and maintain the corresponding Snapshot efficiently
 8type WithSnapshot struct {
 9	*Bug
10	snap *Snapshot
11}
12
13// Snapshot return the current snapshot
14func (b *WithSnapshot) Snapshot() *Snapshot {
15	if b.snap == nil {
16		snap := b.Bug.Compile()
17		b.snap = &snap
18	}
19	return b.snap
20}
21
22// Append intercept Bug.Append() to update the snapshot efficiently
23func (b *WithSnapshot) Append(op Operation) {
24	b.Bug.Append(op)
25
26	if b.snap == nil {
27		return
28	}
29
30	op.Apply(b.snap)
31	b.snap.Operations = append(b.snap.Operations, op)
32}
33
34// Commit intercept Bug.Commit() to update the snapshot efficiently
35func (b *WithSnapshot) Commit(repo repository.ClockedRepo) error {
36	err := b.Bug.Commit(repo)
37
38	if err != nil {
39		b.snap = nil
40		return err
41	}
42
43	// Commit() shouldn't change anything of the bug state apart from the
44	// initial ID set
45
46	if b.snap == nil {
47		return nil
48	}
49
50	b.snap.id = b.Bug.id
51	return nil
52}
53
54// Merge intercept Bug.Merge() and clear the snapshot
55func (b *WithSnapshot) Merge(repo repository.Repo, other Interface) (bool, error) {
56	b.snap = nil
57	return b.Bug.Merge(repo, other)
58}