package market

import (
	"golang.org/x/xerrors"

	"github.com/filecoin-project/go-address"
	"github.com/filecoin-project/go-state-types/abi"
	"github.com/filecoin-project/go-state-types/cbor"
	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
	"github.com/ipfs/go-cid"
	cbg "github.com/whyrusleeping/cbor-gen"

	"github.com/filecoin-project/lotus/chain/actors/adt"
	"github.com/filecoin-project/lotus/chain/types"
)

var Address = builtin0.StorageMarketActorAddr

func Load(store adt.Store, act *types.Actor) (st State, err error) {
	switch act.Code {
	case builtin0.StorageMarketActorCodeID:
		out := state0{store: store}
		err := store.Get(store.Context(), act.Head, &out)
		if err != nil {
			return nil, err
		}
		return &out, nil
	}
	return nil, xerrors.Errorf("unknown actor code %s", act.Code)
}

type State interface {
	cbor.Marshaler
	BalancesChanged(State) bool
	EscrowTable() (BalanceTable, error)
	LockedTable() (BalanceTable, error)
	TotalLocked() (abi.TokenAmount, error)
	StatesChanged(State) bool
	States() (DealStates, error)
	ProposalsChanged(State) bool
	Proposals() (DealProposals, error)
	VerifyDealsForActivation(
		minerAddr address.Address, deals []abi.DealID, currEpoch, sectorExpiry abi.ChainEpoch,
	) (weight, verifiedWeight abi.DealWeight, err error)
}

type BalanceTable interface {
	ForEach(cb func(address.Address, abi.TokenAmount) error) error
	Get(key address.Address) (abi.TokenAmount, error)
}

type DealStates interface {
	ForEach(cb func(id abi.DealID, ds DealState) error) error
	Get(id abi.DealID) (*DealState, bool, error)

	array() adt.Array
	decode(*cbg.Deferred) (*DealState, error)
}

type DealProposals interface {
	ForEach(cb func(id abi.DealID, dp DealProposal) error) error
	Get(id abi.DealID) (*DealProposal, bool, error)

	array() adt.Array
	decode(*cbg.Deferred) (*DealProposal, error)
}

type DealState struct {
	SectorStartEpoch abi.ChainEpoch // -1 if not yet included in proven sector
	LastUpdatedEpoch abi.ChainEpoch // -1 if deal state never updated
	SlashEpoch       abi.ChainEpoch // -1 if deal never slashed
}

type DealProposal struct {
	PieceCID             cid.Cid
	PieceSize            abi.PaddedPieceSize
	VerifiedDeal         bool
	Client               address.Address
	Provider             address.Address
	Label                string
	StartEpoch           abi.ChainEpoch
	EndEpoch             abi.ChainEpoch
	StoragePricePerEpoch abi.TokenAmount
	ProviderCollateral   abi.TokenAmount
	ClientCollateral     abi.TokenAmount
}

type DealStateChanges struct {
	Added    []DealIDState
	Modified []DealStateChange
	Removed  []DealIDState
}

type DealIDState struct {
	ID   abi.DealID
	Deal DealState
}

// DealStateChange is a change in deal state from -> to
type DealStateChange struct {
	ID   abi.DealID
	From *DealState
	To   *DealState
}

type DealProposalChanges struct {
	Added   []ProposalIDState
	Removed []ProposalIDState
}

type ProposalIDState struct {
	ID       abi.DealID
	Proposal DealProposal
}

func EmptyDealState() *DealState {
	return &DealState{
		SectorStartEpoch: -1,
		SlashEpoch:       -1,
		LastUpdatedEpoch: -1,
	}
}