package gameserver

import (
	"fmt"

	"gac-hkrpg-go/internal/common"
	pb "gac-hkrpg-go/protocol/proto"
)

// cwEncounterRewards grants the selected server-side offer, never a list
// supplied by the battle upload. In the reference, gfRouteBattleStageInfoProto
// projects option reward type/id/count into the branch's drop list; the battle
// result applies that option reward on passing the threshold or a perfect clear.
// Perfect clears additionally earn monster Orbs, which are not handled here.
// run must be a detached snapshot which the caller discards on any error.
func cwEncounterRewards(c *common.CurrencyWarsCatalog, run *pb.MPIMAEMCEFH, branch *pb.KKBGIPCAGGH, progress, threshold uint32, runtime ...*common.CurrencyWarsRuntimeState) ([]*pb.KFNCAIHIHCM, error) {
	if branch == nil {
		return nil, fmt.Errorf("CW Encounter selected branch missing")
	}
	if len(runtime) == 1 && cwXaodevGenerated(run, runtime[0]) {
		// xaodev branchDropPreview advertises the node's base gold, already
		// paid by settlement. It is not an additional threshold reward. The
		// server-side source marker survives reconnects and is never a wire tag.
		data, err := common.LoadCurrencyWarsXaodev(c)
		if err != nil {
			return nil, err
		}
		_, node := cwStage(run)
		drops := branch.GetBOAMLLHPNEC().GetNMGIABHIJJB()
		if data.Policy.RewardPolicy != "preview_base_gold_already_paid_by_settlement" || node == nil || len(drops) != 1 || drops[0] == nil || drops[0].FKKGLFOHGGA != pb.MJJIFGINJAJ_MJJIFGINJAJ_item_value || drops[0].FNLMKJLKLFH != 0 || drops[0].Num != node.PICMDONCKCO {
			return nil, fmt.Errorf("CW xaodev Encounter base-gold preview differs")
		}
		return nil, nil
	}
	if progress < threshold {
		return nil, nil
	}
	if branch.BOAMLLHPNEC == nil {
		return nil, fmt.Errorf("CW Encounter selected rewards missing")
	}
	recipes, err := common.LoadCurrencyWarsOrbRecipes()
	if err != nil {
		return nil, err
	}
	var updates []*pb.KFNCAIHIHCM
	for _, drop := range branch.BOAMLLHPNEC.NMGIABHIJJB {
		if drop == nil || drop.Num == 0 {
			return nil, fmt.Errorf("CW Encounter reward is invalid")
		}
		var reward common.CurrencyWarsOrbReward
		switch drop.FKKGLFOHGGA {
		case pb.MJJIFGINJAJ_MJJIFGINJAJ_item_value:
			if drop.FNLMKJLKLFH != 0 {
				return nil, fmt.Errorf("CW Encounter gold identity is invalid")
			}
			reward = common.CurrencyWarsOrbReward{Reward: "Gold", Amount: drop.Num}
		case pb.MJJIFGINJAJ_MJJIFGINJAJ_exp:
			if drop.FNLMKJLKLFH != 0 {
				return nil, fmt.Errorf("CW Encounter EXP identity is invalid")
			}
			reward = common.CurrencyWarsOrbReward{Reward: "Exp", Amount: drop.Num}
		case pb.MJJIFGINJAJ_MJJIFGINJAJ_NLFCABFPJHD:
			reward = common.CurrencyWarsOrbReward{Reward: "Item", ItemID: drop.FNLMKJLKLFH, Count: drop.Num}
		default:
			return nil, fmt.Errorf("CW Encounter reward type %v is not mapped", drop.FKKGLFOHGGA)
		}
		grants, _, err := cwApplyOrbReward(c, run, recipes, reward)
		if err != nil {
			return nil, err
		}
		updates = append(updates, grants...)
	}
	return updates, nil
}