package kvm

import (
	"encoding/xml"
	"strings"
	"testing"
	"time"
)

func TestInstanceMetadata_roundTrip(t *testing.T) {
	t.Parallel()
	created := time.Date(2026, 9, 4, 12, 30, 0, 0, time.FixedZone("CEST", 2*3600))
	raw, err := xml.Marshal(newInstanceMetadata("uid-1", created))
	if err != nil {
		t.Fatalf("Marshal() error = %v", err)
	}
	if !strings.Contains(string(raw), `xmlns="`+metadataURI+`"`) {
		t.Errorf("marshalled metadata lacks the namespace declaration: %s", raw)
	}
	m, err := parseInstanceMetadata(string(raw))
	if err != nil {
		t.Fatalf("parseInstanceMetadata() error = %v", err)
	}
	if !m.managed() || m.UID != "uid-1" {
		t.Errorf("parsed = %+v, want managed with uid-1", m)
	}
	if got := m.createdAt(); !got.Equal(created) || got.Location() != time.UTC {
		t.Errorf("createdAt() = %v, want %v in UTC", got, created)
	}
}

func TestParseInstanceMetadata_libvirtPrefixedForm(t *testing.T) {
	t.Parallel()
	// libvirt re-serialises the stored element with whatever prefix it
	// chooses; only the namespace URI is contractual.
	in := `<op:instance xmlns:op="` + metadataURI + `">` +
		`<op:managed>true</op:managed><op:uid>uid-2</op:uid>` +
		`<op:createdAt>2026-09-04T10:00:00Z</op:createdAt></op:instance>`
	m, err := parseInstanceMetadata(in)
	if err != nil {
		t.Fatalf("parseInstanceMetadata() error = %v", err)
	}
	if !m.managed() || m.UID != "uid-2" || m.createdAt().Hour() != 10 {
		t.Errorf("parsed = %+v", m)
	}
}

func TestParseInstanceMetadata_notManaged(t *testing.T) {
	t.Parallel()
	tests := []struct {
		name    string
		in      string
		wantErr bool
	}{
		{"managed false", `<instance xmlns="` + metadataURI + `"><managed>false</managed><uid>u</uid></instance>`, false},
		{"foreign element", `<foo xmlns="urn:other"><managed>true</managed></foo>`, true},
		{"garbage", `not xml`, true},
	}
	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()
			m, err := parseInstanceMetadata(tc.in)
			if (err != nil) != tc.wantErr {
				t.Fatalf("error = %v, wantErr %v", err, tc.wantErr)
			}
			if m.managed() {
				t.Errorf("managed() = true for %q", tc.in)
			}
		})
	}
}

func TestInstanceMetadata_createdAtMalformedIsZero(t *testing.T) {
	t.Parallel()
	m := instanceMetadata{CreatedAt: "yesterday"}
	if !m.createdAt().IsZero() {
		t.Errorf("createdAt() = %v, want zero time", m.createdAt())
	}
}