package service_event

import (
	"context"
	"nixcn-cms/data"
	"nixcn-cms/internal/exception"
	"nixcn-cms/service/shared"

	"github.com/google/uuid"
	"gorm.io/gorm"
)

type EventInfoData struct {
	EventId uuid.UUID `json:"event_id"`
}

type EventInfoPayload struct {
	Context context.Context
	UserId  uuid.UUID
	Data    *EventInfoData
}

type EventInfoResult struct {
	Common shared.CommonResult
	Data   *data.EventIndexDoc
}

func (self *EventServiceImpl) GetEventInfo(payload *EventInfoPayload) (result *EventInfoResult) {
	event, err := new(data.Event).GetEventById(payload.Context, payload.Data.EventId)
	if err != nil {
		exception := new(exception.Builder).
			SetStatus(exception.StatusUser).
			SetService(exception.ServiceEvent).
			SetEndpoint(exception.EndpointEventServiceInfo).
			SetType(exception.TypeSpecific).
			SetOriginal(exception.EventInfoNotFound).
			SetError(err).
			Throw(payload.Context)

		result = &EventInfoResult{
			Common: shared.CommonResult{
				HttpCode:  404,
				Exception: exception,
			},
		}

		return
	}

	joinCount, err := new(data.Attendance).CountUsersByEventID(payload.Context, payload.Data.EventId)
	if err != nil {
		exception := new(exception.Builder).
			SetStatus(exception.StatusUser).
			SetService(exception.ServiceEvent).
			SetEndpoint(exception.EndpointEventServiceInfo).
			SetType(exception.TypeCommon).
			SetOriginal(exception.CommonErrorDatabase).
			SetError(err).
			Throw(payload.Context)

		result = &EventInfoResult{
			Common: shared.CommonResult{
				HttpCode:  500,
				Exception: exception,
			},
		}

		return
	}

	checkinCount, err := new(data.Attendance).CountCheckedInUsersByEventID(payload.Context, payload.Data.EventId)
	if err != nil {
		exception := new(exception.Builder).
			SetStatus(exception.StatusUser).
			SetService(exception.ServiceEvent).
			SetEndpoint(exception.EndpointEventServiceInfo).
			SetType(exception.TypeCommon).
			SetOriginal(exception.CommonErrorDatabase).
			SetError(err).
			Throw(payload.Context)

		result = &EventInfoResult{
			Common: shared.CommonResult{
				HttpCode:  500,
				Exception: exception,
			},
		}

		return
	}

	var isJoined bool
	joinedInfo, err := new(data.Attendance).GetAttendance(payload.Context, payload.UserId, payload.Data.EventId)
	if err != nil && err != gorm.ErrRecordNotFound {
		exception := new(exception.Builder).
			SetStatus(exception.StatusUser).
			SetService(exception.ServiceEvent).
			SetEndpoint(exception.EndpointEventServiceInfo).
			SetType(exception.TypeCommon).
			SetOriginal(exception.CommonErrorDatabase).
			SetError(err).
			Throw(payload.Context)

		result = &EventInfoResult{
			Common: shared.CommonResult{
				HttpCode:  500,
				Exception: exception,
			},
		}

		return
	} else if err == gorm.ErrRecordNotFound {
		isJoined = false
	} else if joinedInfo.AttendanceId != uuid.Nil {
		isJoined = true
	}

	result = &EventInfoResult{
		Common: shared.CommonResult{
			HttpCode: 200,
			Exception: new(exception.Builder).
				SetStatus(exception.StatusSuccess).
				SetService(exception.ServiceEvent).
				SetEndpoint(exception.EndpointEventServiceInfo).
				SetType(exception.TypeCommon).
				SetOriginal(exception.CommonSuccess).
				Throw(payload.Context),
		},
		Data: &data.EventIndexDoc{
			EventId:      event.EventId.String(),
			Name:         event.Name,
			Type:         event.Type,
			Description:  event.Description,
			StartTime:    event.StartTime,
			EndTime:      event.EndTime,
			Thumbnail:    event.Thumbnail,
			EnableKYC:    event.EnableKYC,
			IsJoined:     isJoined,
			JoinCount:    joinCount,
			CheckinCount: checkinCount,
		},
	}

	return
}