package agent

import (
	"testing"

	corev1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
)

func ptrBool(b bool) *bool { return &b }

func mkPod(name string, owner *metav1.OwnerReference, labels map[string]string, image string) *corev1.Pod {
	p := &corev1.Pod{
		ObjectMeta: metav1.ObjectMeta{Name: name, Labels: labels},
	}
	if owner != nil {
		p.OwnerReferences = []metav1.OwnerReference{*owner}
	}
	if image != "" {
		p.Spec.Containers = []corev1.Container{{Image: image}}
	}
	return p
}

func TestDeriveAppName_DeploymentReplicaSet(t *testing.T) {
	owner := &metav1.OwnerReference{
		Kind:       "ReplicaSet",
		Name:       "traefik-789df685f",
		Controller: ptrBool(true),
	}
	pod := mkPod("traefik-789df685f-hqvfl", owner,
		map[string]string{podTemplateHashLabel: "789df685f"}, "")
	if got := deriveAppName(pod); got != "traefik" {
		t.Fatalf("got %q, want %q", got, "traefik")
	}
}

func TestDeriveAppName_StatefulSet(t *testing.T) {
	owner := &metav1.OwnerReference{
		Kind:       "StatefulSet",
		Name:       "gitea",
		Controller: ptrBool(true),
	}
	pod := mkPod("gitea-0", owner, nil, "")
	if got := deriveAppName(pod); got != "gitea" {
		t.Fatalf("got %q, want %q", got, "gitea")
	}
}

func TestDeriveAppName_DaemonSet(t *testing.T) {
	owner := &metav1.OwnerReference{
		Kind:       "DaemonSet",
		Name:       "flock-agent",
		Controller: ptrBool(true),
	}
	pod := mkPod("flock-agent-abcde", owner, nil, "")
	if got := deriveAppName(pod); got != "flock-agent" {
		t.Fatalf("got %q, want %q", got, "flock-agent")
	}
}

func TestDeriveAppName_BarePod(t *testing.T) {
	pod := mkPod("standalone", nil, nil, "")
	if got := deriveAppName(pod); got != "standalone" {
		t.Fatalf("got %q, want %q", got, "standalone")
	}
}

// TestDeriveAppName_RSWithoutTemplateHash — ReplicaSet owners that don't
// follow the standard "<deploy>-<hash>" naming convention (e.g. a custom
// controller) keep the RS name as-is. All replicas of that RS still align,
// which is the second-best correctness offer.
func TestDeriveAppName_RSWithoutTemplateHash(t *testing.T) {
	owner := &metav1.OwnerReference{
		Kind:       "ReplicaSet",
		Name:       "weird-rs-name",
		Controller: ptrBool(true),
	}
	pod := mkPod("weird-rs-name-xyz", owner, nil, "")
	if got := deriveAppName(pod); got != "weird-rs-name" {
		t.Fatalf("got %q, want %q", got, "weird-rs-name")
	}
}

func TestDeriveAppName_NonControllerOwnerIgnored(t *testing.T) {
	// OwnerReference without Controller=true must be ignored — only the
	// controller owner is the canonical workload.
	owner := &metav1.OwnerReference{
		Kind: "Foo",
		Name: "irrelevant",
		// Controller pointer left nil.
	}
	pod := mkPod("solo", owner, nil, "")
	if got := deriveAppName(pod); got != "solo" {
		t.Fatalf("got %q, want %q", got, "solo")
	}
}

func TestPodImageRef(t *testing.T) {
	pod := mkPod("p", nil, nil, "traefik:v3.5")
	if got := podImageRef(pod); got != "traefik:v3.5" {
		t.Fatalf("got %q, want %q", got, "traefik:v3.5")
	}
	empty := mkPod("p", nil, nil, "")
	if got := podImageRef(empty); got != "" {
		t.Fatalf("got %q, want \"\"", got)
	}
}