package main

import (
	"net/http"
	"net/url"
	"regexp"
	"strings"
	"testing"
)

func withDomain(t *testing.T) Settings {
	t.Helper()
	s := mustParse(t)
	obj(obj(s, "router"), "dns")["domain"] = "home.example.org"
	obj(obj(s, "router"), "dns")["forwarders"] = []any{"1.1.1.1"}
	return s
}

func TestDNSRecordsRoundTrip(t *testing.T) {
	s := withDomain(t)
	err := s.applyDNS([]DNSRecord{
		{Name: "files", Addresses: "192.168.168.20, fd00::20"},
		{Name: "photos.example.org", Addresses: "192.168.168.50"},
		{Name: "*.k8s.stinnesbeck.com", Addresses: "192.168.168.254"},
		{Name: "git.stinnesbeck.com.", Addresses: "10.43.162.50"}, // a trailing dot is fine
		{}, // the add row
	}, []DNSRecord{{Name: "tdf.stinnesbeck.com", Addresses: "10.1.0.254"}})
	if err != nil {
		t.Fatal(err)
	}
	// The wildcard is an override of the name; hosts stay hosts.
	if _, ok := s.dnsMap("overrides")["k8s.stinnesbeck.com"]; !ok {
		t.Fatalf("overrides = %v", s.dnsMap("overrides"))
	}
	if _, ok := s.dnsMap("hosts")["files"]; !ok || len(s.dnsMap("hosts")) != 3 {
		t.Errorf("hosts = %v", s.dnsMap("hosts"))
	}
	rows := s.dnsRecords()
	var names []string
	for _, r := range rows {
		names = append(names, r.Name)
	}
	if strings.Join(names, " ") != "files git.stinnesbeck.com photos.example.org *.k8s.stinnesbeck.com" {
		t.Errorf("rows = %v", names)
	}
	if r := rows[0]; r.Addresses != "192.168.168.20, fd00::20" {
		t.Errorf("files = %+v", r)
	}
	if z := s.forwardZones(); len(z) != 1 || z[0].Name != "tdf.stinnesbeck.com" {
		t.Errorf("zones = %+v", z)
	}
	// The rest of dns survives, and removing everything removes the keys.
	if s.domain() != "home.example.org" || str(s, "router", "dns", "forwarders") == "" && s["router"].(map[string]any)["dns"].(map[string]any)["forwarders"] == nil {
		t.Error("domain or forwarders lost")
	}
	for i := range rows {
		rows[i].Remove = true
	}
	if err := s.applyDNS(rows, nil); err != nil {
		t.Fatal(err)
	}
	if len(s.dnsRecords()) != 0 || len(s.forwardZones()) != 0 || s.domain() == "" {
		t.Errorf("after removing: %v %v %q", s.dnsRecords(), s.forwardZones(), s.domain())
	}
}

func TestDNSRecordsAreChecked(t *testing.T) {
	for name, c := range map[string]struct {
		rec  DNSRecord
		want string
	}{
		"bad name":     {DNSRecord{Name: "no good", Addresses: "10.0.0.1"}, "rec[0].name"},
		"wildcard mid": {DNSRecord{Name: "a.*.example.org", Addresses: "10.0.0.1"}, "rec[0].name"},
		"no address":   {DNSRecord{Name: "files", Addresses: ""}, "rec[0].addresses"},
		"bad address":  {DNSRecord{Name: "files", Addresses: "10.0.0.999"}, "rec[0].addresses"},
		"prefix":       {DNSRecord{Name: "files", Addresses: "10.0.0.1/24"}, "rec[0].addresses"},
		// The sample has a DHCP reservation called nas, which publishes it.
		"reservation": {DNSRecord{Name: "nas", Addresses: "10.0.0.1"}, "rec[0].name"},
	} {
		s := withDomain(t)
		err := s.applyDNS([]DNSRecord{c.rec}, nil)
		if fe, ok := err.(FormErrors); !ok || fe[c.want] == "" {
			t.Errorf("%s: %v", name, err)
		}
	}
	// Two names that are the same once placed in the domain.
	s := withDomain(t)
	if err := s.applyDNS([]DNSRecord{{Name: "web", Addresses: "10.0.0.1"}, {Name: "web.home.example.org", Addresses: "10.0.0.2"}}, nil); err == nil {
		t.Error("web and web.home.example.org were both accepted")
	}
	// A short name needs a domain; a name cannot be there twice.
	s = mustParse(t)
	err := s.applyDNS([]DNSRecord{{Name: "web", Addresses: "10.0.0.1"}}, nil)
	if fe, ok := err.(FormErrors); !ok || !strings.Contains(fe["rec[0].name"], "local domain") {
		t.Errorf("short name without a domain: %v", err)
	}
	if err := s.applyDNS([]DNSRecord{{Name: "a.example.org", Addresses: "10.0.0.1"}, {Name: "a.example.org", Addresses: "10.0.0.2"}}, nil); err == nil {
		t.Error("a name twice was accepted")
	}
	// A wildcard and a plain name of the same name are two different things.
	if err := s.applyDNS([]DNSRecord{{Name: "a.example.org", Addresses: "10.0.0.1"}, {Name: "*.a.example.org", Addresses: "10.0.0.2"}}, nil); err != nil {
		t.Errorf("a name and its wildcard: %v", err)
	}
	if err := s.applyDNS(nil, []DNSRecord{{Name: "*.branch.test", Addresses: "10.0.0.1"}}); err == nil {
		t.Error("a wildcard forward zone was accepted")
	}
}

func TestDNSPage(t *testing.T) {
	a, sys := newTestApp(t)
	h := a.routes()
	cookie := do(h, "POST", "/login", url.Values{"password": {"hunter2hunter2"}}, nil).Result().Cookies()[0]
	body := do(h, "GET", "/dns", nil, cookie).Body.String()
	if !strings.Contains(body, "Forward zones") || !strings.Contains(body, "DHCP reservation") {
		t.Fatalf("page:\n%s", body)
	}
	token := regexp.MustCompile(`name="csrf" value="([^"]+)"`).FindStringSubmatch(body)[1]
	form := url.Values{"csrf": {token}, "recs": {"2"}, "zones": {"0"},
		"rec.0.name": {"*.k8s.stinnesbeck.com"}, "rec.0.addresses": {"192.168.168.254"},
		"rec.1.name": {"web"}, "rec.1.addresses": {"192.168.168.9"}}
	// No local domain in the sample: the short name is refused, nothing is saved.
	if rec := do(h, "POST", "/dns", form, cookie); rec.Code != http.StatusUnprocessableEntity {
		t.Fatalf("short name without domain: %d", rec.Code)
	}
	form.Set("rec.1.name", "web.stinnesbeck.com")
	if rec := do(h, "POST", "/dns", form, cookie); rec.Code != http.StatusSeeOther {
		t.Fatalf("save: %d\n%s", rec.Code, rec.Body)
	}
	s, _ := loadSettings(sys.settingsPath())
	if _, ok := s.dnsMap("overrides")["k8s.stinnesbeck.com"]; !ok {
		t.Errorf("settings: %v", s["router"])
	}
	if body := do(h, "GET", "/dns", nil, cookie).Body.String(); !strings.Contains(body, `value="*.k8s.stinnesbeck.com"`) {
		t.Error("the wildcard is not shown again")
	}
	// Saving the network form must keep them.
	net := do(h, "GET", "/network", nil, cookie).Body.String()
	nt := regexp.MustCompile(`name="csrf" value="([^"]+)"`).FindStringSubmatch(net)[1]
	nf := url.Values{"csrf": {nt}, "hostName": {"gw"}, "wan.interface": {"eth1"}, "wan.type": {"dhcp"}, "lans": {"1"},
		"lan.0.name": {"main"}, "lan.0.interface": {"eth2"}, "lan.0.address": {"192.168.10.1"}, "lan.0.dhcp": {"on"},
		"lan.0.poolStart": {"192.168.10.100"}, "lan.0.poolEnd": {"192.168.10.199"}}
	do(h, "POST", "/network", nf, cookie)
	s, _ = loadSettings(sys.settingsPath())
	if _, ok := s.dnsMap("overrides")["k8s.stinnesbeck.com"]; !ok {
		t.Error("the network form dropped the DNS records")
	}
}