Restructure `webhook` module (#22256)

Previously, there was an `import services/webhooks` inside
`modules/notification/webhook`.
This import was removed (after fighting against many import cycles).
Additionally, `modules/notification/webhook` was moved to
`modules/webhook`,
and a few structs/constants were extracted from `models/webhooks` to
`modules/webhook`.

Co-authored-by: 6543 <6543@obermui.de>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

2 files changed, 133 insertions, 0 deletions

diff --git a/modules/webhook/structs.go b/modules/webhook/structs.go
new file mode 100644
index 0000000000..96012de352
--- /dev/null
+++ b/modules/webhook/structs.go
@@ -0,0 +1,38 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package webhook
+
+// HookEvents is a set of web hook events
+type HookEvents struct {
+	Create               bool `json:"create"`
+	Delete               bool `json:"delete"`
+	Fork                 bool `json:"fork"`
+	Issues               bool `json:"issues"`
+	IssueAssign          bool `json:"issue_assign"`
+	IssueLabel           bool `json:"issue_label"`
+	IssueMilestone       bool `json:"issue_milestone"`
+	IssueComment         bool `json:"issue_comment"`
+	Push                 bool `json:"push"`
+	PullRequest          bool `json:"pull_request"`
+	PullRequestAssign    bool `json:"pull_request_assign"`
+	PullRequestLabel     bool `json:"pull_request_label"`
+	PullRequestMilestone bool `json:"pull_request_milestone"`
+	PullRequestComment   bool `json:"pull_request_comment"`
+	PullRequestReview    bool `json:"pull_request_review"`
+	PullRequestSync      bool `json:"pull_request_sync"`
+	Wiki                 bool `json:"wiki"`
+	Repository           bool `json:"repository"`
+	Release              bool `json:"release"`
+	Package              bool `json:"package"`
+}
+
+// HookEvent represents events that will delivery hook.
+type HookEvent struct {
+	PushOnly       bool   `json:"push_only"`
+	SendEverything bool   `json:"send_everything"`
+	ChooseEvents   bool   `json:"choose_events"`
+	BranchFilter   string `json:"branch_filter"`
+
+	HookEvents `json:"events"`
+}
diff --git a/modules/webhook/type.go b/modules/webhook/type.go
new file mode 100644
index 0000000000..db4ab17931
--- /dev/null
+++ b/modules/webhook/type.go
@@ -0,0 +1,95 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package webhook
+
+// HookEventType is the type of a hook event
+type HookEventType string
+
+// Types of hook events
+const (
+	HookEventCreate                    HookEventType = "create"
+	HookEventDelete                    HookEventType = "delete"
+	HookEventFork                      HookEventType = "fork"
+	HookEventPush                      HookEventType = "push"
+	HookEventIssues                    HookEventType = "issues"
+	HookEventIssueAssign               HookEventType = "issue_assign"
+	HookEventIssueLabel                HookEventType = "issue_label"
+	HookEventIssueMilestone            HookEventType = "issue_milestone"
+	HookEventIssueComment              HookEventType = "issue_comment"
+	HookEventPullRequest               HookEventType = "pull_request"
+	HookEventPullRequestAssign         HookEventType = "pull_request_assign"
+	HookEventPullRequestLabel          HookEventType = "pull_request_label"
+	HookEventPullRequestMilestone      HookEventType = "pull_request_milestone"
+	HookEventPullRequestComment        HookEventType = "pull_request_comment"
+	HookEventPullRequestReviewApproved HookEventType = "pull_request_review_approved"
+	HookEventPullRequestReviewRejected HookEventType = "pull_request_review_rejected"
+	HookEventPullRequestReviewComment  HookEventType = "pull_request_review_comment"
+	HookEventPullRequestSync           HookEventType = "pull_request_sync"
+	HookEventWiki                      HookEventType = "wiki"
+	HookEventRepository                HookEventType = "repository"
+	HookEventRelease                   HookEventType = "release"
+	HookEventPackage                   HookEventType = "package"
+)
+
+// Event returns the HookEventType as an event string
+func (h HookEventType) Event() string {
+	switch h {
+	case HookEventCreate:
+		return "create"
+	case HookEventDelete:
+		return "delete"
+	case HookEventFork:
+		return "fork"
+	case HookEventPush:
+		return "push"
+	case HookEventIssues, HookEventIssueAssign, HookEventIssueLabel, HookEventIssueMilestone:
+		return "issues"
+	case HookEventPullRequest, HookEventPullRequestAssign, HookEventPullRequestLabel, HookEventPullRequestMilestone,
+		HookEventPullRequestSync:
+		return "pull_request"
+	case HookEventIssueComment, HookEventPullRequestComment:
+		return "issue_comment"
+	case HookEventPullRequestReviewApproved:
+		return "pull_request_approved"
+	case HookEventPullRequestReviewRejected:
+		return "pull_request_rejected"
+	case HookEventPullRequestReviewComment:
+		return "pull_request_comment"
+	case HookEventWiki:
+		return "wiki"
+	case HookEventRepository:
+		return "repository"
+	case HookEventRelease:
+		return "release"
+	}
+	return ""
+}
+
+// HookType is the type of a webhook
+type HookType = string
+
+// Types of webhooks
+const (
+	GITEA      HookType = "gitea"
+	GOGS       HookType = "gogs"
+	SLACK      HookType = "slack"
+	DISCORD    HookType = "discord"
+	DINGTALK   HookType = "dingtalk"
+	TELEGRAM   HookType = "telegram"
+	MSTEAMS    HookType = "msteams"
+	FEISHU     HookType = "feishu"
+	MATRIX     HookType = "matrix"
+	WECHATWORK HookType = "wechatwork"
+	PACKAGIST  HookType = "packagist"
+)
+
+// HookStatus is the status of a web hook
+type HookStatus int
+
+// Possible statuses of a web hook
+const (
+	HookStatusNone HookStatus = iota
+	HookStatusSucceed
+	HookStatusFail
+)