package service

import (
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"os"
	"reflect"
	"strings"
	"testing"
	"time"

	"metis/pkg/sentinel"
)

func TestStageDesiredNodeMetadataMergesInventoryAndLiveCluster(t *testing.T) {
	kube := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		switch {
		case r.Method == http.MethodGet && r.URL.Path == "/api/v1/nodes":
			_ = json.NewEncoder(w).Encode(map[string]any{
				"items": []any{
					map[string]any{
						"metadata": map[string]any{
							"name": "titan-15",
							"labels": map[string]string{
								"hardware":                       "rpi5",
								"rack":                           "a1",
								"maintenance.bstein.dev/color":   "blue",
								"kubernetes.io/arch":             "arm64",
								"node-role.kubernetes.io/worker": "true",
							},
							"annotations": map[string]string{
								"maintenance.bstein.dev/owner":                           "atlas",
								"volumes.kubernetes.io/controller-managed-attach-detach": "true",
							},
						},
						"spec": map[string]any{
							"unschedulable": true,
							"taints": []any{
								map[string]any{"key": "dedicated", "value": "recovery", "effect": "NoSchedule"},
								map[string]any{"key": "node.kubernetes.io/unreachable", "effect": "NoExecute"},
							},
						},
					},
				},
			})
		default:
			http.NotFound(w, r)
		}
	}))
	defer kube.Close()
	installKubeFactory(t, kube)

	app := newTestApp(t)
	app.inventory.Nodes[0].Labels = map[string]string{"hardware": "rpi4", "rack": "a1"}
	app.inventory.Nodes[0].Taints = []string{"flash=true:NoSchedule"}
	app.desiredMetadata["titan-15"] = DesiredNodeMetadata{
		Node:        "titan-15",
		Annotations: map[string]string{"maintenance.bstein.dev/legacy": "keep"},
	}

	desired, err := app.stageDesiredNodeMetadata("titan-15")
	if err != nil {
		t.Fatalf("stageDesiredNodeMetadata: %v", err)
	}
	if desired.Hostname != "titan-15" || !desired.Unschedulable {
		t.Fatalf("unexpected desired metadata header: %#v", desired)
	}
	if desired.Labels["hardware"] != "rpi5" || desired.Labels["rack"] != "a1" || desired.Labels["maintenance.bstein.dev/color"] != "blue" {
		t.Fatalf("unexpected desired labels: %#v", desired.Labels)
	}
	if _, ok := desired.Labels["kubernetes.io/arch"]; ok {
		t.Fatalf("system labels should not be persisted: %#v", desired.Labels)
	}
	if desired.Annotations["maintenance.bstein.dev/owner"] != "atlas" || desired.Annotations["maintenance.bstein.dev/legacy"] != "keep" {
		t.Fatalf("unexpected desired annotations: %#v", desired.Annotations)
	}
	if _, ok := desired.Annotations["volumes.kubernetes.io/controller-managed-attach-detach"]; ok {
		t.Fatalf("controller annotations should not be persisted: %#v", desired.Annotations)
	}
	if !reflect.DeepEqual(desired.Taints, []string{"dedicated=recovery:NoSchedule"}) {
		t.Fatalf("unexpected desired taints: %#v", desired.Taints)
	}
	data, err := os.ReadFile(app.settings.DesiredMetadataPath)
	if err != nil {
		t.Fatalf("read desired metadata file: %v", err)
	}
	if !strings.Contains(string(data), "titan-15") {
		t.Fatalf("desired metadata file missing titan-15: %s", string(data))
	}
}

func TestStoreSnapshotRestoresDesiredNodeMetadata(t *testing.T) {
	var patchBody map[string]any
	kube := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		switch {
		case r.Method == http.MethodGet && r.URL.Path == "/api/v1/nodes":
			_ = json.NewEncoder(w).Encode(map[string]any{
				"items": []any{
					map[string]any{
						"metadata": map[string]any{
							"name": "titan-15",
							"labels": map[string]string{
								"hardware":                   "rpi4",
								"maintenance.bstein.dev/old": "1",
							},
							"annotations": map[string]string{
								"maintenance.bstein.dev/mode": "old",
							},
						},
						"spec": map[string]any{
							"unschedulable": true,
							"taints": []any{
								map[string]any{"key": "dedicated", "value": "old", "effect": "NoSchedule"},
								map[string]any{"key": "node.kubernetes.io/unreachable", "effect": "NoExecute"},
							},
						},
					},
				},
			})
		case r.Method == http.MethodPatch && r.URL.Path == "/api/v1/nodes/titan-15":
			if err := json.NewDecoder(r.Body).Decode(&patchBody); err != nil {
				t.Fatalf("decode patch: %v", err)
			}
			_ = json.NewEncoder(w).Encode(map[string]any{"status": "ok"})
		default:
			http.NotFound(w, r)
		}
	}))
	defer kube.Close()
	installKubeFactory(t, kube)

	app := newTestApp(t)
	app.desiredMetadata["titan-15"] = DesiredNodeMetadata{
		Node:          "titan-15",
		Hostname:      "titan-15",
		Labels:        map[string]string{"hardware": "rpi5"},
		Annotations:   map[string]string{"maintenance.bstein.dev/mode": "recovery"},
		Taints:        []string{"dedicated=recovery:NoSchedule"},
		Unschedulable: false,
	}

	if err := app.StoreSnapshot(SnapshotRecord{
		Node:        "titan-15",
		CollectedAt: time.Date(2026, 4, 24, 6, 0, 0, 0, time.UTC),
		Snapshot:    sentinel.Snapshot{Hostname: "titan-15"},
	}); err != nil {
		t.Fatalf("StoreSnapshot: %v", err)
	}
	if patchBody == nil {
		t.Fatal("expected desired metadata patch")
	}
	metadata := patchBody["metadata"].(map[string]any)
	labels := metadata["labels"].(map[string]any)
	if labels["hardware"] != "rpi5" || labels["maintenance.bstein.dev/old"] != nil {
		t.Fatalf("unexpected label patch: %#v", labels)
	}
	annotations := metadata["annotations"].(map[string]any)
	if annotations["maintenance.bstein.dev/mode"] != "recovery" {
		t.Fatalf("unexpected annotation patch: %#v", annotations)
	}
	spec := patchBody["spec"].(map[string]any)
	if spec["unschedulable"] != false {
		t.Fatalf("unexpected spec patch: %#v", spec)
	}
	taints := spec["taints"].([]any)
	if len(taints) != 2 {
		t.Fatalf("unexpected taint payload: %#v", taints)
	}
	entries := map[string]map[string]any{}
	for _, raw := range taints {
		entry := raw.(map[string]any)
		key := entry["key"].(string)
		entries[key] = entry
	}
	if entries["dedicated"]["value"] != "recovery" || entries["dedicated"]["effect"] != "NoSchedule" {
		t.Fatalf("missing desired taint replacement: %#v", entries)
	}
	if entries["node.kubernetes.io/unreachable"]["effect"] != "NoExecute" {
		t.Fatalf("system taint should be preserved: %#v", entries)
	}
}

func TestDesiredNodeMetadataHelpers(t *testing.T) {
	app := newTestApp(t)
	if _, ok := app.desiredMetadataForNode("missing"); ok {
		t.Fatal("expected no desired metadata for missing node")
	}
	if err := app.syncDesiredNodeMetadata(SnapshotRecord{Node: "missing"}); err != nil {
		t.Fatalf("syncDesiredNodeMetadata missing should noop: %v", err)
	}
	if _, ok := liveClusterNode(""); ok {
		t.Fatal("empty liveClusterNode lookup should fail")
	}
	if !isRestorableLabel("maintenance.bstein.dev/role") || isRestorableLabel("kubernetes.io/arch") {
		t.Fatal("unexpected label restoration filter")
	}
	if !isRestorableAnnotation("maintenance.bstein.dev/state") || isRestorableAnnotation("volumes.kubernetes.io/foo") {
		t.Fatal("unexpected annotation restoration filter")
	}
	if !isRestorableTaint("dedicated=recovery:NoSchedule") || isRestorableTaint("node.kubernetes.io/not-ready:NoExecute") {
		t.Fatal("unexpected taint restoration filter")
	}
	key, value, effect := splitTaint("dedicated=recovery:NoSchedule")
	if key != "dedicated" || value != "recovery" || effect != "NoSchedule" {
		t.Fatalf("splitTaint mismatch: %q %q %q", key, value, effect)
	}
	if key, value, effect := splitTaint("just-a-key"); key != "just-a-key" || value != "" || effect != "" {
		t.Fatalf("splitTaint key-only mismatch: %q %q %q", key, value, effect)
	}
	labels := filteredRestorableLabels(map[string]string{"hardware": "rpi5", "kubernetes.io/arch": "arm64"})
	if !reflect.DeepEqual(labels, map[string]string{"hardware": "rpi5"}) {
		t.Fatalf("filteredRestorableLabels = %#v", labels)
	}
	annotations := filteredRestorableAnnotations(map[string]string{"maintenance.bstein.dev/state": "ok", "volumes.kubernetes.io/foo": "bar"})
	if !reflect.DeepEqual(annotations, map[string]string{"maintenance.bstein.dev/state": "ok"}) {
		t.Fatalf("filteredRestorableAnnotations = %#v", annotations)
	}
	patch := metadataStringPatch(
		map[string]string{"hardware": "rpi4", "maintenance.bstein.dev/old": "1"},
		map[string]string{"hardware": "rpi5"},
		isRestorableLabel,
	)
	if patch["hardware"] != "rpi5" || patch["maintenance.bstein.dev/old"] != nil {
		t.Fatalf("metadataStringPatch = %#v", patch)
	}
	mergedTaints := mergeLiveAndDesiredTaints(
		[]string{"node.kubernetes.io/unreachable:NoExecute", "dedicated=old:NoSchedule"},
		[]string{"dedicated=new:NoSchedule", "dedicated=new:NoSchedule"},
	)
	if !reflect.DeepEqual(mergedTaints, []string{"dedicated=new:NoSchedule", "node.kubernetes.io/unreachable:NoExecute"}) {
		t.Fatalf("mergeLiveAndDesiredTaints = %#v", mergedTaints)
	}
	payload := taintPatchPayload([]string{"dedicated=new:NoSchedule"})
	if len(payload) != 1 || payload[0]["key"] != "dedicated" || payload[0]["value"] != "new" || payload[0]["effect"] != "NoSchedule" {
		t.Fatalf("taintPatchPayload = %#v", payload)
	}
	original := DesiredNodeMetadata{Labels: map[string]string{"hardware": "rpi5"}, Taints: []string{"dedicated=new:NoSchedule"}}
	cloned := cloneDesiredNodeMetadata(original)
	cloned.Labels["hardware"] = "mutated"
	cloned.Taints[0] = "changed"
	if original.Labels["hardware"] != "rpi5" || original.Taints[0] != "dedicated=new:NoSchedule" {
		t.Fatalf("cloneDesiredNodeMetadata should deep-copy slices/maps: %#v %#v", original, cloned)
	}
	if err := patchDesiredNodeMetadata(
		clusterNode{Name: "titan-15", Labels: map[string]string{"hardware": "rpi5"}, Taints: []string{"dedicated=new:NoSchedule"}},
		DesiredNodeMetadata{Node: "titan-15", Labels: map[string]string{"hardware": "rpi5"}, Taints: []string{"dedicated=new:NoSchedule"}},
	); err != nil {
		t.Fatalf("patchDesiredNodeMetadata should noop when already in sync: %v", err)
	}
	if event := desiredNodeMetadataSyncEvent("titan-15", os.ErrPermission); event.Kind != "sentinel.node-metadata" || event.Details["node"] != "titan-15" {
		t.Fatalf("desiredNodeMetadataSyncEvent = %#v", event)
	}
}