package main

import (
	"encoding/json"
	"strings"
	"testing"

	admission "k8s.io/api/admission/v1beta1"
	networking "k8s.io/api/networking/v1beta1"
	meta "k8s.io/apimachinery/pkg/apis/meta/v1"
	runtime "k8s.io/apimachinery/pkg/runtime"
)

func TestPatterns(t *testing.T) {
	f := ingressFilter{}
	// Test that sane filters are allowed.
	for _, el := range []struct {
		ns     string
		domain string
	}{
		{"matrix", "matrix.hackerspace.pl"},
		{"ceph-waw3", "*.hackerspace.pl"},
		{"personal-q3k", "*.k0.q3k.org"},
		{"personal-vuko", "shells.vuko.pl"},
		{"minecraft", "*.k0.q3k.org"},
	} {
		err := f.allow(el.ns, el.domain)
		if err != nil {
			t.Fatalf("allow(%q, %q): %v", el.ns, el.domain, err)
		}
	}
	// Test that broken patterns are rejected.
	if err := f.allow("borked", "*.hackerspace.*"); err == nil {
		t.Fatalf("allow(double star): wanted err, got nil")
	}
	if err := f.allow("borked", ""); err == nil {
		t.Fatalf("allow(empty): wanted err, got nil")
	}
	if err := f.allow("borked", "*foo.example.com"); err == nil {
		t.Fatalf("allow(partial wildcard): wanted err, got nil")
	}
}

func TestMatch(t *testing.T) {
	f := ingressFilter{}
	// Errors discarded, tested in TestPatterns.
	f.allow("matrix", "matrix.hackerspace.pl")
	f.allow("ceph-waw3", "*.hackerspace.pl")
	f.allow("personal-q3k", "*.k0.q3k.org")
	f.allow("personal-vuko", "shells.vuko.pl")
	f.allow("minecraft", "*.k0.q3k.org")

	for _, el := range []struct {
		ns       string
		dns      string
		expected bool
	}{
		// Explicitly allowed.
		{"matrix", "matrix.hackerspace.pl", true},
		// *.hackerspace.pl is explicitly mentioned in ceph-waw3, so this is
		// forbidden.
		{"matrix", "matrix2.hackerspace.pl", false},
		// Hackers should not be able to take over critical domains.
		{"personal-hacker", "matrix.hackerspace.pl", false},
		{"personal-hacker", "totallylegit.hackerspace.pl", false},
		// q3k can do his thing, even nested..
		{"personal-q3k", "foo.k0.q3k.org", true},
		{"personal-q3k", "foo.bar.k0.q3k.org", true},
		// counterintuitive: only *.k0.q3k.org is constrained, so k0.q3k.org
		// (as anything.q3k.org) is allowed everywhere.
		{"personal-hacker", "k0.q3k.org", true},
		// vuko's shell service is only allowed in his NS.
		{"personal-vuko", "shells.vuko.pl", true},
		// counterintuitive: vuko.pl is allowed everywhere else, too. This is
		// because there's no *.vuko.pl wildcard anywhere, so nothing would
		// block it. Solution: add an explicit *.vuko.pl wildcard to the
		// namespace, or just don't do a wildcard CNAME redirect to our
		// ingress.
		{"personal-hacker", "foobar.vuko.pl", true},
		// Unknown domains are fine.
		{"personal-hacker", "www.github.com", true},
	} {
		if want, got := el.expected, f.domainAllowed(el.ns, el.dns); got != want {
			t.Errorf("%q on %q is %v, wanted %v", el.dns, el.ns, got, want)
		}
	}
}

func TestIngressPermitted(t *testing.T) {
	f := ingressFilter{}
	// Errors discarded, tested in TestPatterns.
	f.allow("matrix", "matrix.hackerspace.pl")
	f.allow("ceph-waw3", "*.hackerspace.pl")
	f.allow("personal-q3k", "*.k0.q3k.org")
	f.allow("personal-vuko", "shells.vuko.pl")
	f.allow("minecraft", "*.k0.q3k.org")

	mkReq := func(ns string, annotations map[string]string, is *networking.IngressSpec) *admission.AdmissionRequest {
		i := &networking.Ingress{
			Spec: *is,
		}
		i.Annotations = annotations
		raw, err := json.Marshal(i)
		if err != nil {
			t.Fatalf("marshaling test ingress: %v", err)
		}
		return &admission.AdmissionRequest{
			UID: "test",
			Kind: meta.GroupVersionKind{
				Group:   "networking.k8s.io",
				Version: "v1beta1",
				Kind:    "Ingress",
			},
			Namespace: ns,
			Operation: "CREATE",
			Object: runtime.RawExtension{
				Raw: raw,
			},
		}
	}

	for i, el := range []struct {
		req *admission.AdmissionRequest
		err string
	}{
		// 0: unrelated domain, should be allowed
		{mkReq("default", nil, &networking.IngressSpec{
			Rules: []networking.IngressRule{
				{Host: "example.com"},
			},
			TLS: []networking.IngressTLS{
				{
					Hosts: []string{"example.com"},
				},
			},
		}), ""},
		// 1: permitted restricted domain, should be allowed
		{mkReq("matrix", nil, &networking.IngressSpec{
			Rules: []networking.IngressRule{
				{Host: "matrix.hackerspace.pl"},
			},
			TLS: []networking.IngressTLS{
				{
					Hosts: []string{"matrix.hackerspace.pl"},
				},
			},
		}), ""},
		// 2: forbidden restricted domain, should be rejected
		{mkReq("personal-hacker", nil, &networking.IngressSpec{
			Rules: []networking.IngressRule{
				{Host: "matrix.hackerspace.pl"},
			},
			TLS: []networking.IngressTLS{
				{
					Hosts: []string{"matrix.hackerspace.pl"},
				},
			},
		}), "not allowed in namespace"},
		// 3: weird ingress but okay
		{mkReq("personal-hacker", nil, &networking.IngressSpec{}), ""},
		// 4: janky annotations, should be rejected
		{mkReq("matrix", map[string]string{
			"nginx.ingress.kubernetes.io/configuration-snippet": "omghax",
		}, &networking.IngressSpec{
			Rules: []networking.IngressRule{
				{Host: "matrix.hackerspace.pl"},
			},
			TLS: []networking.IngressTLS{
				{
					Hosts: []string{"matrix.hackerspace.pl"},
				},
			},
		}), "forbidden annotation"},
		// 5: accepted annotations, should be allowed
		{mkReq("matrix", map[string]string{
			"nginx.ingress.kubernetes.io/proxy-body-size": "2137",
			"foo.q3k.org/bar": "baz",
		}, &networking.IngressSpec{
			Rules: []networking.IngressRule{
				{Host: "matrix.hackerspace.pl"},
			},
			TLS: []networking.IngressTLS{
				{
					Hosts: []string{"matrix.hackerspace.pl"},
				},
			},
		}), ""},
	} {
		res, err := f.admit(el.req)
		if err != nil {
			t.Errorf("test %d: admit: %v", i, err)
		}
		if el.err == "" {
			if !res.Allowed {
				t.Errorf("test %d: wanted allow, got %q", i, res.Result.Message)
			}
		} else {
			if res.Allowed {
				t.Errorf("test %d: wanted %q, got allowed", i, el.err)
			} else if !strings.Contains(res.Result.Message, el.err) {
				t.Errorf("test %d: wanted %q, got %q", i, el.err, res.Result.Message)
			}
		}
	}
}