package smartcontract

import (
	"github.com/CityOfZion/neo-go/pkg/io"
	"github.com/CityOfZion/neo-go/pkg/util"
)

// ParamType represents the Type of the contract parameter.
type ParamType byte

// A list of supported smart contract parameter types.
const (
	SignatureType ParamType = iota
	BoolType
	IntegerType
	Hash160Type
	Hash256Type
	ByteArrayType
	PublicKeyType
	StringType
	ArrayType
)

// PropertyState represents contract properties (flags).
type PropertyState byte

// List of supported properties.
const (
	HasStorage PropertyState = 1 << iota
	HasDynamicInvoke
	IsPayable
	NoProperties = 0
)

// Parameter represents a smart contract parameter.
type Parameter struct {
	// Type of the parameter.
	Type ParamType `json:"type"`
	// The actual value of the parameter.
	Value interface{} `json:"value"`
}

func (pt ParamType) String() string {
	switch pt {
	case SignatureType:
		return "Signature"
	case BoolType:
		return "Boolean"
	case IntegerType:
		return "Integer"
	case Hash160Type:
		return "Hash160"
	case Hash256Type:
		return "Hash256"
	case ByteArrayType:
		return "ByteArray"
	case PublicKeyType:
		return "PublicKey"
	case StringType:
		return "String"
	case ArrayType:
		return "Array"
	default:
		return ""
	}
}

// MarshalJSON implements the json.Marshaler interface.
func (pt ParamType) MarshalJSON() ([]byte, error) {
	return []byte(`"` + pt.String() + `"`), nil
}

// EncodeBinary implements io.Serializable interface.
func (pt ParamType) EncodeBinary(w *io.BinWriter) {
	w.WriteLE(pt)
}

// DecodeBinary implements io.Serializable interface.
func (pt *ParamType) DecodeBinary(r *io.BinReader) {
	r.ReadLE(pt)
}

// NewParameter returns a Parameter with proper initialized Value
// of the given ParamType.
func NewParameter(t ParamType) Parameter {
	return Parameter{
		Type:  t,
		Value: nil,
	}
}

// ContextItem represents a transaction context item.
type ContextItem struct {
	Script     util.Uint160
	Parameters []Parameter
	Signatures []Signature
}

// Signature represents a transaction signature.
type Signature struct {
	Data      []byte
	PublicKey []byte
}

// ParameterContext holds the parameter context.
type ParameterContext struct{}