package apply

import (
	"context"
	"sort"
	"strings"

	"github.com/novox/mesh-host/internal/declaration"
	"github.com/novox/mesh-host/internal/store"
)

// Strays is what runs on the machine that the mesh neither wrote nor holds (novox/hq ADR 0163):
// every container the runtime has that no record names and no hold names. The question nothing
// answered on 2026-09-23, when a renamed resource left its old container running for a day; asked
// on every apply now, and reported, so a thing left behind is seen the day it is left.
//
// Containers only, today. A listener nobody declared is harder to attribute to a thing, and the
// machine's own services are not strays; that account is issue 160's.
func Strays(ctx context.Context, run Runner, known store.State) ([]store.Stray, error) {
	cri, err := containerRuntime(ctx, run)
	if err != nil {
		return nil, nil // a machine with no runtime has no containers to stray
	}
	out, err := run(ctx, cri, "ps", "-a", "--format", "{{.Names}}\t{{.Image}}\t{{.State}}")
	if err != nil {
		return nil, err
	}
	ours := map[string]bool{}
	for _, r := range known.Resources {
		if declaration.Type(r.Type) == declaration.TypeContainer {
			ours[r.Target] = true
		}
	}
	for _, h := range known.Held {
		if h.Kind == string(declaration.TypeContainer) {
			ours[h.Target] = true
		}
	}
	var strays []store.Stray
	for _, line := range strings.Split(strings.TrimSpace(out), "\n") {
		parts := strings.Split(line, "\t")
		name := strings.TrimSpace(parts[0])
		if name == "" || ours[name] {
			continue
		}
		detail := ""
		if len(parts) > 2 {
			detail = strings.TrimSpace(parts[1]) + ", " + strings.TrimSpace(parts[2])
		}
		strays = append(strays, store.Stray{Kind: string(declaration.TypeContainer), Name: name, Detail: detail})
	}
	sort.Slice(strays, func(i, j int) bool { return strays[i].Name < strays[j].Name })
	return strays, nil
}