Mod event and user table, add event CURD

Signed-off-by: Asai Neko <sugar@sne.moe>

data/event.go

@@ -1,28 +1,81 @@
 package data
 
 import (
+	"errors"
+	"slices"
 	"time"
 
 	"github.com/google/uuid"
+	"gorm.io/datatypes"
+	"gorm.io/gorm"
+	"gorm.io/gorm/clause"
 )
 
 type Event struct {
-	Id        uint      `json:"id" gorm:"primarykey;autoincrement"`
-	UUID      uuid.UUID `json:"uuid" gorm:"type:uuid;uniqueindex;not null"`
-	EventId   uuid.UUID `json:"event_id" gorm:"type:uuid;uniqueindex;not null"`
-	Name      string    `json:"name" gorm:"type:varchar(255);index;not null"`
-	StartTime time.Time `json:"start_time" gorm:"index"`
-	EndTime   time.Time `json:"end_time" gorm:"index"`
+	Id          uint                           `json:"id" gorm:"primarykey;autoincrement"`
+	UUID        uuid.UUID                      `json:"uuid" gorm:"type:uuid;uniqueIndex;not null"`
+	EventId     uuid.UUID                      `json:"event_id" gorm:"type:uuid;uniqueIndex;not null"`
+	Name        string                         `json:"name" gorm:"type:varchar(255);index;not null"`
+	StartTime   time.Time                      `json:"start_time" gorm:"index"`
+	EndTime     time.Time                      `json:"end_time" gorm:"index"`
+	JoinedUsers datatypes.JSONSlice[uuid.UUID] `json:"joined_users"`
 }
 
 func (self *Event) GetEventById(eventId uuid.UUID) error {
-	return nil
+	return Database.Transaction(func(tx *gorm.DB) error {
+		if err := tx.Where("event_id = ?", eventId).First(&self).Error; err != nil {
+			return err
+		}
+		return nil
+	})
 }
 
 func (self *Event) UpdateEventById(eventId uuid.UUID) error {
-	return nil
+	return Database.Transaction(func(tx *gorm.DB) error {
+		if err := tx.Model(&Event{}).Where("event_id = ?", eventId).Updates(&self).Error; err != nil {
+			return err
+		}
+		return nil
+	})
 }
 
 func (self *Event) CreateEvent() error {
-	return nil
+	if self.UUID == uuid.Nil {
+		self.UUID = uuid.New()
+	}
+	if self.EventId == uuid.Nil {
+		self.EventId = uuid.New()
+	}
+
+	return Database.Transaction(func(tx *gorm.DB) error {
+		if err := tx.Create(&self).Error; err != nil {
+			return err
+		}
+		return nil
+	})
+}
+
+func (self *Event) UserJoinEvent(userId, eventId uuid.UUID) error {
+	return Database.Transaction(func(tx *gorm.DB) error {
+		var event Event
+		if err := tx.Clauses(clause.Locking{Strength: "UPDATE"}).
+			Where("event_id = ?", eventId).
+			First(&event).Error; err != nil {
+			return err
+		}
+
+		// Check if user already joined
+		if slices.Contains(event.JoinedUsers, userId) {
+			return errors.New("user already joined")
+		}
+
+		// Add user to list
+		event.JoinedUsers = append(event.JoinedUsers, userId)
+		if err := tx.Model(&Event{}).Where("event_id = ?", eventId).Update("joined_users", event.JoinedUsers).Error; err != nil {
+			return err
+		}
+
+		*self = event
+		return nil
+	})
 }