app/calendar/event.go

package calendar

import (
	"time"

	"github.com/rs/xid"
	"gorm.io/gorm"
	"kumoly.io/kumoly/app/errors"
)

type Event struct {
	ID string `gorm:"primaryKey"`

	Start    time.Time
	End      time.Time
	Name     string `gorm:"not null"`
	Location string

	Color string `gorm:"-"`

	IsExt bool

	CalendarID   string
	EventGroup   EventGroup `json:"Detial"`
	EventGroupID string

	CreatedAt time.Time
	UpdatedAt time.Time
}

func (e *Event) BeforeSave(tx *gorm.DB) (err error) {
	if e.CalendarID == "" {
		return errors.ErrorBadRequest
	}
	if e.Location == "" {
		loc := ""
		tx.Raw("select name from calendars where id = ?", e.CalendarID).Scan(&loc)
		e.Location = loc
	}

	// test for collide
	cnt := ""
	db.Raw(`select id from events e where 
		(? >= "start" and ? <= "end" )
		or
		(? >= "start" and ? <= "end"  )
		and calendar_id = ? and id <> ? limit 1`,
		e.End, e.End, e.Start, e.Start, e.CalendarID, e.ID).Scan(&cnt)
	if cnt != "" {
		return errors.New(500, "event collide with existing")
	}

	return
}

func (e *Event) BeforeCreate(tx *gorm.DB) (err error) {
	if e.ID == "" {
		e.ID = xid.New().String()
	}
	e.IsExt = false
	return
}

func (e *Event) AfterFind(tx *gorm.DB) (err error) {
	eg := EventGroup{}
	if err := tx.First(&eg, "id = ?", e.EventGroupID).Error; err != nil {
		return err
	}
	e.EventGroup = eg
	e.Color = Color[e.EventGroup.Color%len(Color)]
	return
}