Move issues related files into models/issues (#19931)

* Move access and repo permission to models/perm/access

* fix test

* fix git test

* Move functions sequence

* Some improvements per @KN4CK3R and @delvh

* Move issues related code to models/issues

* Move some issues related sub package

* Merge

* Fix test

* Fix test

* Fix test

* Fix test

* Rename some files

models/issues/issue_lock.go

@@ -0,0 +1,65 @@
+// Copyright 2019 The Gitea 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 issues
+
+import (
+	"code.gitea.io/gitea/models/db"
+	user_model "code.gitea.io/gitea/models/user"
+)
+
+// IssueLockOptions defines options for locking and/or unlocking an issue/PR
+type IssueLockOptions struct {
+	Doer   *user_model.User
+	Issue  *Issue
+	Reason string
+}
+
+// LockIssue locks an issue. This would limit commenting abilities to
+// users with write access to the repo
+func LockIssue(opts *IssueLockOptions) error {
+	return updateIssueLock(opts, true)
+}
+
+// UnlockIssue unlocks a previously locked issue.
+func UnlockIssue(opts *IssueLockOptions) error {
+	return updateIssueLock(opts, false)
+}
+
+func updateIssueLock(opts *IssueLockOptions, lock bool) error {
+	if opts.Issue.IsLocked == lock {
+		return nil
+	}
+
+	opts.Issue.IsLocked = lock
+	var commentType CommentType
+	if opts.Issue.IsLocked {
+		commentType = CommentTypeLock
+	} else {
+		commentType = CommentTypeUnlock
+	}
+
+	ctx, committer, err := db.TxContext()
+	if err != nil {
+		return err
+	}
+	defer committer.Close()
+
+	if err := UpdateIssueCols(ctx, opts.Issue, "is_locked"); err != nil {
+		return err
+	}
+
+	opt := &CreateCommentOptions{
+		Doer:    opts.Doer,
+		Issue:   opts.Issue,
+		Repo:    opts.Issue.Repo,
+		Type:    commentType,
+		Content: opts.Reason,
+	}
+	if _, err := CreateCommentCtx(ctx, opt); err != nil {
+		return err
+	}
+
+	return committer.Commit()
+}