package domain

import "time"

const (
	ConnectionConnected    = "connected"
	ConnectionError        = "error"
	ConnectionDisconnected = "disconnected"
)

// Account is a Threads OAuth binding (tokens server-only).
type Account struct {
	ID                 string `bson:"_id" json:"id"`
	OwnerUID           int64  `bson:"owner_uid" json:"owner_uid"`
	Username           string `bson:"username" json:"username"`
	DisplayName        string `bson:"display_name" json:"display_name"`
	ThreadsUserID      string `bson:"threads_user_id" json:"threads_user_id"`
	Connection         string `bson:"connection" json:"connection"`
	IsUsable           bool   `bson:"is_usable" json:"is_usable"`
	AvatarColor        string `bson:"avatar_color,omitempty" json:"avatar_color,omitempty"`
	AvatarURL          string `bson:"avatar_url,omitempty" json:"avatar_url,omitempty"`
	ErrorMessage       string `bson:"error_message,omitempty" json:"error_message,omitempty"`
	SessionExpiresAt   int64  `bson:"session_expires_at,omitempty" json:"session_expires_at,omitempty"`
	SessionRefreshedAt int64  `bson:"session_refreshed_at,omitempty" json:"session_refreshed_at,omitempty"`
	// Encrypted tokens — never expose via public DTO
	AccessTokenEnc  string `bson:"access_token_enc,omitempty" json:"-"`
	RefreshTokenEnc string `bson:"refresh_token_enc,omitempty" json:"-"`
	CreatedAt       int64  `bson:"created_at" json:"created_at"`
	UpdatedAt       int64  `bson:"updated_at" json:"updated_at"`
}

// OAuthState binds CSRF state to member for callback.
type OAuthState struct {
	State     string `bson:"_id"`
	OwnerUID  int64  `bson:"owner_uid"`
	CreatedAt int64  `bson:"created_at"`
	ExpiresAt int64  `bson:"expires_at"`
}

// TokenPair from provider exchange (in-memory only).
type TokenPair struct {
	AccessToken  string
	RefreshToken string
	ExpiresIn    int64 // seconds
	UserID       string
	Username     string
	DisplayName  string
	AvatarURL    string
}

func NowNano() int64 { return time.Now().UTC().UnixNano() }

func AvatarColorFor(username string) string {
	colors := []string{"#6dbf7a", "#5b8def", "#e8a54b", "#c77dff", "#f07178"}
	if username == "" {
		return colors[0]
	}
	var h int
	for _, r := range username {
		h = (h*31 + int(r)) % len(colors)
	}
	if h < 0 {
		h = -h
	}
	return colors[h%len(colors)]
}