1package operations
 2
 3import (
 4	"github.com/MichaelMure/git-bug/bug"
 5	"sort"
 6)
 7
 8// LabelChangeOperation will add or remove a set of labels
 9
10var _ bug.Operation = LabelChangeOperation{}
11
12type LabelChangeOperation struct {
13	bug.OpBase
14	Added   []bug.Label
15	Removed []bug.Label
16}
17
18func NewLabelChangeOperation(author bug.Person, added, removed []bug.Label) LabelChangeOperation {
19	return LabelChangeOperation{
20		OpBase:  bug.NewOpBase(bug.LabelChangeOp, author),
21		Added:   added,
22		Removed: removed,
23	}
24}
25
26func (op LabelChangeOperation) Apply(snapshot bug.Snapshot) bug.Snapshot {
27	// Add in the set
28AddLoop:
29	for _, added := range op.Added {
30		for _, label := range snapshot.Labels {
31			if label == added {
32				// Already exist
33				continue AddLoop
34			}
35		}
36
37		snapshot.Labels = append(snapshot.Labels, added)
38	}
39
40	// Remove in the set
41	for _, removed := range op.Removed {
42		for i, label := range snapshot.Labels {
43			if label == removed {
44				snapshot.Labels[i] = snapshot.Labels[len(snapshot.Labels)-1]
45				snapshot.Labels = snapshot.Labels[:len(snapshot.Labels)-1]
46			}
47		}
48	}
49
50	// Sort
51	sort.Slice(snapshot.Labels, func(i, j int) bool {
52		return string(snapshot.Labels[i]) < string(snapshot.Labels[j])
53	})
54
55	return snapshot
56}