Move some code into models/git (#19879)

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

* fix test

* Move some git related files into sub package models/git

* Fix build

* fix git test

* move lfs to sub package

* move more git related functions to models/git

* Move functions sequence

* Some improvements per @KN4CK3R and @delvh

models/branch.go

@@ -0,0 +1,80 @@
+// Copyright 2022 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 models
+
+import (
+	"context"
+
+	"code.gitea.io/gitea/models/db"
+	git_model "code.gitea.io/gitea/models/git"
+	"code.gitea.io/gitea/modules/log"
+)
+
+// HasEnoughApprovals returns true if pr has enough granted approvals.
+func HasEnoughApprovals(ctx context.Context, protectBranch *git_model.ProtectedBranch, pr *PullRequest) bool {
+	if protectBranch.RequiredApprovals == 0 {
+		return true
+	}
+	return GetGrantedApprovalsCount(ctx, protectBranch, pr) >= protectBranch.RequiredApprovals
+}
+
+// GetGrantedApprovalsCount returns the number of granted approvals for pr. A granted approval must be authored by a user in an approval whitelist.
+func GetGrantedApprovalsCount(ctx context.Context, protectBranch *git_model.ProtectedBranch, pr *PullRequest) int64 {
+	sess := db.GetEngine(ctx).Where("issue_id = ?", pr.IssueID).
+		And("type = ?", ReviewTypeApprove).
+		And("official = ?", true).
+		And("dismissed = ?", false)
+	if protectBranch.DismissStaleApprovals {
+		sess = sess.And("stale = ?", false)
+	}
+	approvals, err := sess.Count(new(Review))
+	if err != nil {
+		log.Error("GetGrantedApprovalsCount: %v", err)
+		return 0
+	}
+
+	return approvals
+}
+
+// MergeBlockedByRejectedReview returns true if merge is blocked by rejected reviews
+func MergeBlockedByRejectedReview(ctx context.Context, protectBranch *git_model.ProtectedBranch, pr *PullRequest) bool {
+	if !protectBranch.BlockOnRejectedReviews {
+		return false
+	}
+	rejectExist, err := db.GetEngine(ctx).Where("issue_id = ?", pr.IssueID).
+		And("type = ?", ReviewTypeReject).
+		And("official = ?", true).
+		And("dismissed = ?", false).
+		Exist(new(Review))
+	if err != nil {
+		log.Error("MergeBlockedByRejectedReview: %v", err)
+		return true
+	}
+
+	return rejectExist
+}
+
+// MergeBlockedByOfficialReviewRequests block merge because of some review request to official reviewer
+// of from official review
+func MergeBlockedByOfficialReviewRequests(ctx context.Context, protectBranch *git_model.ProtectedBranch, pr *PullRequest) bool {
+	if !protectBranch.BlockOnOfficialReviewRequests {
+		return false
+	}
+	has, err := db.GetEngine(ctx).Where("issue_id = ?", pr.IssueID).
+		And("type = ?", ReviewTypeRequest).
+		And("official = ?", true).
+		Exist(new(Review))
+	if err != nil {
+		log.Error("MergeBlockedByOfficialReviewRequests: %v", err)
+		return true
+	}
+
+	return has
+}
+
+// MergeBlockedByOutdatedBranch returns true if merge is blocked by an outdated head branch
+func MergeBlockedByOutdatedBranch(protectBranch *git_model.ProtectedBranch, pr *PullRequest) bool {
+	return protectBranch.BlockOnOutdatedBranch && pr.CommitsBehind > 0
+}