package recovery

import (
	"context"
	"log"

	"git.k6n.net/mats/go-cart-actor/pkg/cart"
)

// LoggingNotifier is the v0 default: it writes one INFO line per candidate
// and returns nil. It deliberately does NOT pretend to send anything.
//
// Future implementations (MailerSend, FCM, APNs) implement the same Notifier
// interface; the scanner doesn't change. LoggingNotifier also serves as the
// "dry-run" mode in production by leaving the seam unconfigured.
type LoggingNotifier struct{}

// NewLoggingNotifier returns a Notifier that logs every candidate. The struct
// is empty today; the constructor is kept for parity with future notifiers
// that need credentials / config.
func NewLoggingNotifier() *LoggingNotifier { return &LoggingNotifier{} }

// NotifyAbandoned logs the cart id, contact present, and a tiny summary.
// Push tokens are summarized by platform only — never log the raw token, so
// a misconfigured log aggregator can't leak device handles.
func (LoggingNotifier) NotifyAbandoned(_ context.Context, c RecoveryCandidate) error {
	hasEmail := c.Email != ""
	hasPush := len(c.PushTokens) > 0
	channel := "none"
	switch {
	case hasEmail && hasPush:
		channel = "email+push"
	case hasEmail:
		channel = "email"
	case hasPush:
		channel = "push"
	}
	log.Printf(
		"recovery [dry-run]: cart=%d user=%q channel=%s items=%d total=%d currency=%s email=%q pushPlatforms=%v lastChangeUnix=%d",
		c.CartID,
		c.UserID,
		channel,
		c.ItemCount,
		c.TotalIncVat,
		c.Currency,
		c.Email,
		platformsOf(c.PushTokens),
		c.LastChangeUnix,
	)
	return nil
}

func platformsOf(tokens []cart.PushToken) []string {
	out := make([]string, 0, len(tokens))
	for _, t := range tokens {
		out = append(out, t.Platform)
	}
	return out
}