package wallet

import (
	"github.com/p9c/p9/pkg/amt"
	"github.com/p9c/p9/pkg/btcaddr"
	"time"
	
	"github.com/p9c/p9/pkg/chainhash"
	"github.com/p9c/p9/pkg/wire"
)

// Note: The following common types should never reference the Wallet type. Long term goal is to move these to their own
// package so that the database access APIs can create them directly for the wallet to return.

// BlockIdentity identifies a block, or the lack of one (used to describe an unmined transaction).
type BlockIdentity struct {
	Hash   chainhash.Hash
	Height int32
}

// None returns whether there is no block described by the instance. When associated with a transaction, this indicates
// the transaction is unmined.
func (b *BlockIdentity) None() bool {
	// BUG: Because dcrwallet uses both 0 and -1 in various places to refer to an unmined transaction this must check
	// against both and may not ever be usable to represent the genesis block.
	return *b == BlockIdentity{Height: -1} || *b == BlockIdentity{}
}

// OutputKind describes a kind of transaction output. This is used to differentiate between coinbase, stakebase, and
// normal outputs.
type OutputKind byte

// Defined OutputKind constants
const (
	OutputKindNormal OutputKind = iota
	OutputKindCoinbase
)

// TransactionOutput describes an output that was or is at least partially controlled by the wallet. Depending on
// context, this could refer to an unspent output, or a spent one.
type TransactionOutput struct {
	OutPoint   wire.OutPoint
	Output     wire.TxOut
	OutputKind OutputKind
	// These should be added later when the DB can return them more efficiently:
	//
	// TxLockTime      uint32
	// TxExpiry        uint32
	ContainingBlock BlockIdentity
	ReceiveTime     time.Time
}

// OutputRedeemer identifies the transaction input which redeems an output.
type OutputRedeemer struct {
	TxHash     chainhash.Hash
	InputIndex uint32
}

// P2SHMultiSigOutput describes a transaction output with a pay-to-script-hash output script and an imported redemption
// script. Along with common details of the output, this structure also includes the P2SH address the script was created
// from and the number of signatures required to redeem it.
//
// TODO: Could be useful to return how many of the required signatures can be created by this wallet.
type P2SHMultiSigOutput struct {
	// TODO: Add a TransactionOutput member to this struct and remove these fields which are duplicated by it. This
	//  improves consistency. Only not done now because wtxmgr APIs don't support an efficient way of fetching other
	//  Transactionoutput data together with the rest of the multisig info.
	OutPoint        wire.OutPoint
	OutputAmount    amt.Amount
	ContainingBlock BlockIdentity
	P2SHAddress     *btcaddr.ScriptHash
	RedeemScript    []byte
	M, N            uint8           // M of N signatures required to redeem
	Redeemer        *OutputRedeemer // nil unless spent
}