Added forks

internal/models/gist.go

@@ -16,10 +16,13 @@ type Gist struct {
 	User            User `validate:"-"`
 	NbFiles         int
 	NbLikes         int
+	NbForks         int
 	CreatedAt       int64
 	UpdatedAt       int64
 
-	Likes []User `gorm:"many2many:likes;constraint:OnUpdate:CASCADE,OnDelete:CASCADE"`
+	Likes    []User `gorm:"many2many:likes;constraint:OnUpdate:CASCADE,OnDelete:CASCADE"`
+	Forked   *Gist  `gorm:"foreignKey:ForkedID;constraint:OnUpdate:CASCADE,OnDelete:SET NULL"`
+	ForkedID uint
 
 	Files []File `gorm:"-" validate:"min=1,dive"`
 }
@@ -40,7 +43,7 @@ type Commit struct {
 
 func GetGist(user string, gistUuid string) (*Gist, error) {
 	gist := new(Gist)
-	err := db.Preload("User").
+	err := db.Preload("User").Preload("Forked.User").
 		Where("gists.uuid = ? AND users.username like ?", gistUuid, user).
 		Joins("join users on gists.user_id = users.id").
 		First(&gist).Error
@@ -50,7 +53,7 @@ func GetGist(user string, gistUuid string) (*Gist, error) {
 
 func GetGistByID(gistId string) (*Gist, error) {
 	gist := new(Gist)
-	err := db.Preload("User").
+	err := db.Preload("User").Preload("Forked.User").
 		Where("gists.id = ?", gistId).
 		First(&gist).Error
 
@@ -59,7 +62,7 @@ func GetGistByID(gistId string) (*Gist, error) {
 
 func GetAllGistsForCurrentUser(currentUserId uint, offset int, sort string, order string) ([]*Gist, error) {
 	var gists []*Gist
-	err := db.Preload("User").
+	err := db.Preload("User").Preload("Forked.User").
 		Where("gists.private = 0 or gists.user_id = ?", currentUserId).
 		Limit(11).
 		Offset(offset * 10).
@@ -82,7 +85,7 @@ func GetAllGists(offset int) ([]*Gist, error) {
 
 func GetAllGistsFromUser(fromUser string, currentUserId uint, offset int, sort string, order string) ([]*Gist, error) {
 	var gists []*Gist
-	err := db.Preload("User").
+	err := db.Preload("User").Preload("Forked.User").
 		Where("users.username = ? and ((gists.private = 0) or (gists.private = 1 and gists.user_id = ?))", fromUser, currentUserId).
 		Joins("join users on gists.user_id = users.id").
 		Limit(11).
@@ -94,11 +97,16 @@ func GetAllGistsFromUser(fromUser string, currentUserId uint, offset int, sort s
 }
 
 func CreateGist(gist *Gist) error {
+	// avoids foreign key constraint error because the default value in the struct is 0
+	return db.Omit("forked_id").Create(&gist).Error
+}
+
+func CreateForkedGist(gist *Gist) error {
 	return db.Create(&gist).Error
 }
 
 func UpdateGist(gist *Gist) error {
-	return db.Save(&gist).Error
+	return db.Omit("forked_id").Save(&gist).Error
 }
 
 func DeleteGist(gist *Gist) error {
@@ -112,16 +120,40 @@ func GistLastActiveNow(gistID uint) error {
 }
 
 func AppendUserLike(gist *Gist, user *User) error {
-	db.Model(&gist).Omit("updated_at").Update("nb_likes", gist.NbLikes+1)
+	err := db.Model(&gist).Omit("updated_at").Update("nb_likes", gist.NbLikes+1).Error
+	if err != nil {
+		return err
+	}
+
 	return db.Model(&gist).Omit("updated_at").Association("Likes").Append(user)
 }
 
 func RemoveUserLike(gist *Gist, user *User) error {
-	db.Model(&gist).Omit("updated_at").Update("nb_likes", gist.NbLikes-1)
+	err := db.Model(&gist).Omit("updated_at").Update("nb_likes", gist.NbLikes-1).Error
+	if err != nil {
+		return err
+	}
+
 	return db.Model(&gist).Omit("updated_at").Association("Likes").Delete(user)
 }
 
-func GetUsersLikesForGists(gist *Gist, offset int) ([]*User, error) {
+func IncrementGistForkCount(gist *Gist) error {
+	return db.Model(&gist).Omit("updated_at").Update("nb_forks", gist.NbForks+1).Error
+}
+
+func DecrementGistForkCount(gist *Gist) error {
+	return db.Model(&gist).Omit("updated_at").Update("nb_forks", gist.NbForks-1).Error
+}
+
+func GetForkedGist(gist *Gist, user *User) (*Gist, error) {
+	fork := new(Gist)
+	err := db.Preload("User").
+		Where("forked_id = ? and user_id = ?", gist.ID, user.ID).
+		First(&fork).Error
+	return fork, err
+}
+
+func GetUsersLikesForGist(gist *Gist, offset int) ([]*User, error) {
 	var users []*User
 	err := db.Model(&gist).
 		Where("gist_id = ?", gist.ID).
@@ -131,6 +163,19 @@ func GetUsersLikesForGists(gist *Gist, offset int) ([]*User, error) {
 	return users, err
 }
 
+func GetUsersForksForGist(gist *Gist, currentUserId uint, offset int) ([]*Gist, error) {
+	var gists []*Gist
+	err := db.Model(&gist).Preload("User").
+		Where("forked_id = ?", gist.ID).
+		Where("(gists.private = 0) or (gists.private = 1 and gists.user_id = ?)", currentUserId).
+		Limit(11).
+		Offset(offset * 10).
+		Order("updated_at desc").
+		Find(&gists).Error
+
+	return gists, err
+}
+
 func UserCanWrite(user *User, gist *Gist) bool {
 	return !(user == nil) && (gist.UserID == user.ID)
 }