package gorm

import (
	"github.com/jinzhu/gorm"
	"src.dualinventive.com/go/assets-service/internal/domain"
	"src.dualinventive.com/go/assets-service/internal/storage"
	"src.dualinventive.com/go/lib/dilog"
)

//AssetRepository reflects a gorm based AssetRepository
type AssetRepository struct {
	DB     *gorm.DB
	logger dilog.Logger
}

var sortMapping = map[domain.SortCol]SortColQuery{ //nolint: gochecknoglobals
	domain.SortColIDAsc:        SortColQueryIDAsc,
	domain.SortColIDDesc:       SortColQueryIDDesc,
	domain.SortColUIDAsc:       SortColQueryUIDAsc,
	domain.SortColUIDDesc:      SortColQueryUIDDesc,
	domain.SortColSerialNrAsc:  SortColQuerySerialNrAsc,
	domain.SortColSerialNrDesc: SortColQuerySerialNrDesc,
}

//NewAssetRepository returns a new gorm based storage.AssetRepository
func NewAssetRepository(logger dilog.Logger, host, port, name, user, pass string) (storage.AssetRepository, error) {
	db, err := openDB(host, port, name, user, pass)
	if err != nil {
		return nil, err
	}
	repo := &AssetRepository{
		DB:     db,
		logger: logger,
	}
	return repo, nil
}

//GetAssetByID returns an asset by the given assetID or nil if not found.
func (r *AssetRepository) GetAssetByID(assetID uint64) (*domain.Asset, error) {
	var asset domain.Asset
	err := r.DB.
		Where(&domain.Asset{ID: uint(assetID)}).
		First(&asset).Error
	if err == gorm.ErrRecordNotFound {
		return nil, nil
	}
	if err != nil {
		return nil, err
	}

	return &asset, nil
}

//GetAssets returns all assets or nil if not found.
func (r *AssetRepository) GetAssets(
	page uint64, perPage uint64, sort domain.SortCol) (
	[]domain.Asset, uint64, error) {
	var assets []domain.Asset
	var count uint64

	order, ok := sortMapping[sort]
	if !ok {
		order = SortColQueryIDAsc
	}

	err := r.DB.
		Where(&domain.Asset{ID: uint(0)}).
		Order(order.String()).
		Offset((page - 1) * perPage).
		Limit(perPage).
		Find(&assets).
		Offset(0). // Count doesn't work with offset (https://github.com/jinzhu/gorm/issues/1752)
		Count(&count).
		Error
	if err == gorm.ErrRecordNotFound {
		return nil, 0, nil
	}
	if err != nil {
		return nil, 0, err
	}

	return assets, count, nil
}

// SortColQuery represents the sorting column
type SortColQuery string

// SortColQuery constants
const (
	SortColQueryIDAsc        SortColQuery = "device_id asc"
	SortColQueryIDDesc       SortColQuery = "device_id desc"
	SortColQueryUIDAsc       SortColQuery = "device_uid asc"
	SortColQueryUIDDesc      SortColQuery = "device_uid desc"
	SortColQuerySerialNrAsc  SortColQuery = "serial_nr asc"
	SortColQuerySerialNrDesc SortColQuery = "serial_nr desc"
)

// String for MsgType
func (scq SortColQuery) String() string {
	return string(scq)
}