package protocol

import (
	"hash-of-wisdom/internal/pow/challenge"
	"hash-of-wisdom/internal/quotes"
)

// MessageType represents the type of protocol message
type MessageType byte

const (
	ChallengeRequest  MessageType = 0x01
	ChallengeResponse MessageType = 0x02
	SolutionRequest   MessageType = 0x03
	QuoteResponse     MessageType = 0x04
	ErrorResponse     MessageType = 0x05
)

// Message represents a protocol message with type and payload
type Message struct {
	Type    MessageType
	Payload []byte
}

// ChallengeRequestPayload is empty (no payload for challenge requests)
type ChallengeRequestPayload struct{}

// ChallengeResponsePayload is the direct challenge object (not wrapped)
type ChallengeResponsePayload challenge.Challenge

// SolutionRequestPayload contains the client's solution attempt
type SolutionRequestPayload struct {
	Challenge challenge.Challenge `json:"challenge"`
	Nonce     uint64              `json:"nonce"`
}

// QuoteResponsePayload is the direct quote object (not wrapped)
type QuoteResponsePayload quotes.Quote

// ErrorResponsePayload contains error information
type ErrorResponsePayload struct {
	Code       string            `json:"code"`
	Message    string            `json:"message"`
	RetryAfter int               `json:"retry_after,omitempty"`
	Details    map[string]string `json:"details,omitempty"`
}

// Error codes as defined in protocol specification
const (
	ErrMalformedMessage    = "MALFORMED_MESSAGE"
	ErrInvalidChallenge    = "INVALID_CHALLENGE"
	ErrInvalidSolution     = "INVALID_SOLUTION"
	ErrExpiredChallenge    = "EXPIRED_CHALLENGE"
	ErrRateLimited         = "RATE_LIMITED"
	ErrServerError         = "SERVER_ERROR"
	ErrTooManyConnections  = "TOO_MANY_CONNECTIONS"
	ErrDifficultyTooHigh   = "DIFFICULTY_TOO_HIGH"
)

// Protocol constants
const (
	MaxPayloadSize = 8 * 1024 // 8KB maximum payload size
	HeaderSize     = 5        // 1 byte type + 4 bytes length
)