package console

import (
	"context"
	"log"

	"github.com/carlosframework/platform/internal/provision"
)

// discrepancyScanCap bounds one app's record listing. ListRecords treats
// max=0 as "list nothing", so the cap must be explicit.
const discrepancyScanCap = 10000

// LogPlacementDiscrepancies is spec §5.7 step 4, run once at console
// start. For each app holding a non-home region, it lists records with an
// empty region created after the app — the shape a console rolled back
// below the floor would have written. Shapes that never inherit the app
// default are skipped (static, addr-backed, replica, pooled, fleet). A
// deliberate home override looks the same and the record keeps no
// provenance, so each line is a CANDIDATE for review, worded as one (C29).
// It only logs: an error is reported and skipped, never returned, so the
// check can neither block nor fail console start.
func (s *Server) LogPlacementDiscrepancies(ctx context.Context) {
	s.logPlacementDiscrepancies(ctx, discrepancyScanCap)
}

func (s *Server) logPlacementDiscrepancies(ctx context.Context, scanCap int) {
	if s.cfg.Releases == nil {
		return
	}
	apps, err := s.store.NonHomeAppRegions()
	if err != nil {
		log.Printf("console: placement discrepancy check: %v", err)
		return
	}
	for _, a := range apps {
		recs, truncated, err := provision.ListRecords(ctx, s.cfg.Releases, a.Sqid, a.App, scanCap)
		if err != nil {
			log.Printf("console: placement discrepancy check %s/%s: %v", a.Sqid, a.App, err)
			continue
		}
		if truncated {
			log.Printf("console: placement discrepancy check %s/%s: only the first %d records were checked", a.Sqid, a.App, scanCap)
		}
		for _, r := range recs {
			if r.Region != "" || r.Role != "" || r.Pool != "" || !r.DerivesPaths() || r.CreatedAt.Before(a.CreatedAt) {
				continue
			}
			log.Print("console: " + msgPlacementDiscrepancy(r.Host, a.App, a.Region))
		}
	}
}