Some repository refactors (#17950)

* some repository refactors

* remove unnecessary code

* Fix test

* Remove unnecessary banner

models/repo/watch.go

@@ -0,0 +1,196 @@
+// Copyright 2017 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 repo
+
+import (
+	"context"
+
+	"code.gitea.io/gitea/models/db"
+	user_model "code.gitea.io/gitea/models/user"
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/timeutil"
+)
+
+// WatchMode specifies what kind of watch the user has on a repository
+type WatchMode int8
+
+const (
+	// WatchModeNone don't watch
+	WatchModeNone WatchMode = iota // 0
+	// WatchModeNormal watch repository (from other sources)
+	WatchModeNormal // 1
+	// WatchModeDont explicit don't auto-watch
+	WatchModeDont // 2
+	// WatchModeAuto watch repository (from AutoWatchOnChanges)
+	WatchModeAuto // 3
+)
+
+// Watch is connection request for receiving repository notification.
+type Watch struct {
+	ID          int64              `xorm:"pk autoincr"`
+	UserID      int64              `xorm:"UNIQUE(watch)"`
+	RepoID      int64              `xorm:"UNIQUE(watch)"`
+	Mode        WatchMode          `xorm:"SMALLINT NOT NULL DEFAULT 1"`
+	CreatedUnix timeutil.TimeStamp `xorm:"INDEX created"`
+	UpdatedUnix timeutil.TimeStamp `xorm:"INDEX updated"`
+}
+
+func init() {
+	db.RegisterModel(new(Watch))
+}
+
+// GetWatch gets what kind of subscription a user has on a given repository; returns dummy record if none found
+func GetWatch(ctx context.Context, userID, repoID int64) (Watch, error) {
+	watch := Watch{UserID: userID, RepoID: repoID}
+	has, err := db.GetEngine(ctx).Get(&watch)
+	if err != nil {
+		return watch, err
+	}
+	if !has {
+		watch.Mode = WatchModeNone
+	}
+	return watch, nil
+}
+
+// IsWatchMode Decodes watchability of WatchMode
+func IsWatchMode(mode WatchMode) bool {
+	return mode != WatchModeNone && mode != WatchModeDont
+}
+
+// IsWatching checks if user has watched given repository.
+func IsWatching(userID, repoID int64) bool {
+	watch, err := GetWatch(db.DefaultContext, userID, repoID)
+	return err == nil && IsWatchMode(watch.Mode)
+}
+
+func watchRepoMode(ctx context.Context, watch Watch, mode WatchMode) (err error) {
+	if watch.Mode == mode {
+		return nil
+	}
+	if mode == WatchModeAuto && (watch.Mode == WatchModeDont || IsWatchMode(watch.Mode)) {
+		// Don't auto watch if already watching or deliberately not watching
+		return nil
+	}
+
+	hadrec := watch.Mode != WatchModeNone
+	needsrec := mode != WatchModeNone
+	repodiff := 0
+
+	if IsWatchMode(mode) && !IsWatchMode(watch.Mode) {
+		repodiff = 1
+	} else if !IsWatchMode(mode) && IsWatchMode(watch.Mode) {
+		repodiff = -1
+	}
+
+	watch.Mode = mode
+
+	e := db.GetEngine(ctx)
+
+	if !hadrec && needsrec {
+		watch.Mode = mode
+		if _, err = e.Insert(watch); err != nil {
+			return err
+		}
+	} else if needsrec {
+		watch.Mode = mode
+		if _, err := e.ID(watch.ID).AllCols().Update(watch); err != nil {
+			return err
+		}
+	} else if _, err = e.Delete(Watch{ID: watch.ID}); err != nil {
+		return err
+	}
+	if repodiff != 0 {
+		_, err = e.Exec("UPDATE `repository` SET num_watches = num_watches + ? WHERE id = ?", repodiff, watch.RepoID)
+	}
+	return err
+}
+
+// WatchRepoMode watch repository in specific mode.
+func WatchRepoMode(userID, repoID int64, mode WatchMode) (err error) {
+	var watch Watch
+	if watch, err = GetWatch(db.DefaultContext, userID, repoID); err != nil {
+		return err
+	}
+	return watchRepoMode(db.DefaultContext, watch, mode)
+}
+
+// WatchRepoCtx watch or unwatch repository.
+func WatchRepoCtx(ctx context.Context, userID, repoID int64, doWatch bool) (err error) {
+	var watch Watch
+	if watch, err = GetWatch(ctx, userID, repoID); err != nil {
+		return err
+	}
+	if !doWatch && watch.Mode == WatchModeAuto {
+		err = watchRepoMode(ctx, watch, WatchModeDont)
+	} else if !doWatch {
+		err = watchRepoMode(ctx, watch, WatchModeNone)
+	} else {
+		err = watchRepoMode(ctx, watch, WatchModeNormal)
+	}
+	return err
+}
+
+// WatchRepo watch or unwatch repository.
+func WatchRepo(userID, repoID int64, watch bool) (err error) {
+	return WatchRepoCtx(db.DefaultContext, userID, repoID, watch)
+}
+
+// GetWatchers returns all watchers of given repository.
+func GetWatchers(ctx context.Context, repoID int64) ([]*Watch, error) {
+	watches := make([]*Watch, 0, 10)
+	return watches, db.GetEngine(ctx).Where("`watch`.repo_id=?", repoID).
+		And("`watch`.mode<>?", WatchModeDont).
+		And("`user`.is_active=?", true).
+		And("`user`.prohibit_login=?", false).
+		Join("INNER", "`user`", "`user`.id = `watch`.user_id").
+		Find(&watches)
+}
+
+// GetRepoWatchersIDs returns IDs of watchers for a given repo ID
+// but avoids joining with `user` for performance reasons
+// User permissions must be verified elsewhere if required
+func GetRepoWatchersIDs(ctx context.Context, repoID int64) ([]int64, error) {
+	ids := make([]int64, 0, 64)
+	return ids, db.GetEngine(ctx).Table("watch").
+		Where("watch.repo_id=?", repoID).
+		And("watch.mode<>?", WatchModeDont).
+		Select("user_id").
+		Find(&ids)
+}
+
+// GetRepoWatchers returns range of users watching given repository.
+func GetRepoWatchers(repoID int64, opts db.ListOptions) ([]*user_model.User, error) {
+	sess := db.GetEngine(db.DefaultContext).Where("watch.repo_id=?", repoID).
+		Join("LEFT", "watch", "`user`.id=`watch`.user_id").
+		And("`watch`.mode<>?", WatchModeDont)
+	if opts.Page > 0 {
+		sess = db.SetSessionPagination(sess, &opts)
+		users := make([]*user_model.User, 0, opts.PageSize)
+
+		return users, sess.Find(&users)
+	}
+
+	users := make([]*user_model.User, 0, 8)
+	return users, sess.Find(&users)
+}
+
+func watchIfAuto(ctx context.Context, userID, repoID int64, isWrite bool) error {
+	if !isWrite || !setting.Service.AutoWatchOnChanges {
+		return nil
+	}
+	watch, err := GetWatch(ctx, userID, repoID)
+	if err != nil {
+		return err
+	}
+	if watch.Mode != WatchModeNone {
+		return nil
+	}
+	return watchRepoMode(ctx, watch, WatchModeAuto)
+}
+
+// WatchIfAuto subscribes to repo if AutoWatchOnChanges is set
+func WatchIfAuto(userID, repoID int64, isWrite bool) error {
+	return watchIfAuto(db.DefaultContext, userID, repoID, isWrite)
+}