/*
Real-time Online/Offline Charging System (OCS) for Telecom & ISP environments
Copyright (C) ITsysCOM GmbH

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>
*/

package engine

import (
	"fmt"

	"github.com/cgrates/cgrates/utils"
)

func NewLeastCostSorter(spS *SupplierService) *LeastCostSorter {
	return &LeastCostSorter{spS: spS,
		sorting: utils.MetaLeastCost}
}

// LeastCostSorter sorts suppliers based on their cost
type LeastCostSorter struct {
	sorting string
	spS     *SupplierService
}

func (lcs *LeastCostSorter) SortSuppliers(prflID string,
	suppls []*Supplier, ev *utils.CGREvent) (sortedSuppls *SortedSuppliers, err error) {
	sortedSuppls = &SortedSuppliers{ProfileID: prflID,
		Sorting:         lcs.sorting,
		SortedSuppliers: make([]*SortedSupplier, 0)}
	for _, s := range suppls {
		costData, err := lcs.spS.costForEvent(ev, s.AccountIDs, s.RatingPlanIDs)
		if err != nil {
			return nil, err
		} else if len(costData) == 0 {
			utils.Logger.Warning(
				fmt.Sprintf("<%s> profile: %s ignoring supplier with ID: %s, missing cost information",
					utils.SupplierS, prflID, s.ID))
			continue
		}
		srtData := map[string]interface{}{
			utils.Weight: s.Weight,
		}
		for k, v := range costData {
			srtData[k] = v
		}
		sortedSuppls.SortedSuppliers = append(sortedSuppls.SortedSuppliers, &SortedSupplier{
			SupplierID:         s.ID,
			SortingData:        srtData,
			SupplierParameters: s.SupplierParameters})
	}
	sortedSuppls.SortCost()
	return
}