package server

import (
	"context"
	"crypto/tls"
	"encoding/json"
	"net/http"
	"os"
	"strings"
	"testing"
	"time"

	"jarl/internal/auth"
	"jarl/internal/model"
)

// certUser creates a service user with grants and returns a token.
func certUser(t *testing.T, e *apiEnv, name string, grants ...string) (string, *model.User) {
	t.Helper()
	gs := []model.Grant{}
	for _, s := range grants {
		g, err := auth.ParseGrant(s)
		if err != nil {
			t.Fatal(err)
		}
		gs = append(gs, g)
	}
	u := &model.User{Username: name, Grants: gs}
	if err := e.st.CreateUser(context.Background(), u); err != nil {
		t.Fatal(err)
	}
	tok, pid, sh := auth.NewToken()
	if err := e.st.CreateToken(context.Background(), &model.Token{UserID: u.ID, Name: name + "-host", PublicID: pid, SecretHash: sh}); err != nil {
		t.Fatal(err)
	}
	return tok, u
}

// obtained gives a certificate a current certificate, as if the CA had
// signed it.
func obtained(t *testing.T, e *apiEnv, name string, domains ...string) {
	t.Helper()
	certFile, keyFile := selfSigned(t, t.TempDir(), domains...)
	cb, _ := os.ReadFile(certFile)
	kb, _ := os.ReadFile(keyFile)
	ctx := context.Background()
	for i := 0; i < 50 && e.srv.cfg.Certs.Issuing(name) != (time.Time{}); i++ {
		time.Sleep(20 * time.Millisecond) // the failing attempt (no CA) ends
	}
	c, err := e.st.CertificateByName(ctx, name)
	if err != nil {
		t.Fatal(err)
	}
	na, nb := time.Now().Add(30*24*time.Hour), time.Now()
	c.CertPEM, c.KeyPEM, c.NotAfter, c.NotBefore, c.Serial, c.Failures, c.LastError = string(cb), string(kb), &na, &nb, "s-"+name, 0, ""
	if err := e.st.UpdateCertificate(ctx, c); err != nil {
		t.Fatal(err)
	}
}

func TestCertGet(t *testing.T) {
	e := newAPIEnv(t)
	withCerts(e)
	mx, mxUser := certUser(t, e, "mx", "certificates:write names=*.adbraun.lol")
	other, _ := certUser(t, e, "other", "certificates:write names=*.adbraun.lol")
	wide, _ := certUser(t, e, "wide", "*:write")

	req := func(tok, name string, domains ...string) (map[string]any, int) {
		b, status := e.req("POST", "/certificates/"+name+"/request", tok, map[string]any{"domains": domains})
		var out map[string]any
		_ = jsonUnmarshal(b, &out)
		return out, status
	}
	// "*" doesn't cover certificates.
	if _, st := req(wide, "mail", "mail.adbraun.lol"); st != 403 {
		t.Errorf("*:write: %d", st)
	}
	// Names outside the grant.
	if out, st := req(mx, "mail", "mail.example.org"); st != 403 || !strings.Contains(errMsg(out), "mail.example.org") {
		t.Errorf("other names: %d %v", st, out)
	}
	// A new certificate, owned by mx.
	if out, st := req(mx, "mail", "mail.adbraun.lol"); st != 200 && st != 202 || out["created"] != true {
		t.Fatalf("create: %d %v", st, out)
	}
	c, _ := e.st.CertificateByName(context.Background(), "mail")
	if c.OwnerID != mxUser.ID || len(c.Uses) != 0 {
		t.Errorf("owner %d uses %v", c.OwnerID, c.Uses)
	}
	// Another user can't have the name, or see it.
	if out, st := req(other, "mail", "mail.adbraun.lol"); st != 409 || !strings.Contains(errMsg(out), "taken") {
		t.Errorf("taken: %d %v", st, out)
	}
	e.do("GET", "/certificates/mail", other, nil, 404)
	if l := e.do("GET", "/certificates", other, nil, 200)["certificates"].([]any); len(l) != 0 {
		t.Errorf("other's list: %v", l)
	}
	// Nothing to download until it is obtained.
	e.do("GET", "/certificates/mail/pem", mx, nil, 400)
	obtained(t, e, "mail", "mail.adbraun.lol")

	// The same names: the same certificate.
	if out, st := req(mx, "mail", "mail.adbraun.lol"); st != 200 || out["created"] != false || out["changed"] != false {
		t.Errorf("again: %d %v", st, out)
	}
	if c2, _ := e.st.CertificateByName(context.Background(), "mail"); c2.Serial != "s-mail" {
		t.Errorf("replaced: %v", c2.Serial)
	}
	// Download: recorded, with the token.
	if b, st := e.req("GET", "/certificates/mail/pem?part=key", mx, nil); st != 200 || !strings.Contains(string(b), "PRIVATE KEY") {
		t.Errorf("key: %d", st)
	}
	got := e.do("GET", "/certificates/mail", e.token, nil, 200)
	pulls, _ := got["pulled_by"].([]any)
	if got["owner"] != "mx" || len(pulls) != 1 || !strings.Contains(pulls[0].(map[string]any)["who"].(string), "mx-host") || pulls[0].(map[string]any)["serial"] != "s-mail" {
		t.Errorf("owner %v pulled_by %v", got["owner"], got["pulled_by"])
	}
	// A name added: obtained again.
	if out, st := req(mx, "mail", "mail.adbraun.lol", "smtp.adbraun.lol"); out["changed"] != true || st != 200 && st != 202 {
		t.Errorf("SAN added: %d %v", st, out)
	}
	// The owner's own list.
	if l := e.do("GET", "/certificates", mx, nil, 200)["certificates"].([]any); len(l) != 1 {
		t.Errorf("mx's list: %v", l)
	}
	// Jarl's own certificates are the administrators'.
	certFile, keyFile := selfSigned(t, t.TempDir(), "jarl.adbraun.lol")
	e.do("POST", "/certificates", e.token, map[string]any{"name": "web", "source": "file", "cert_file": certFile, "key_file": keyFile}, 201)
	if _, st := req(mx, "web", "jarl.adbraun.lol"); st != 409 {
		t.Errorf("Jarl's own: %d", st)
	}
	e.do("GET", "/certificates/web/pem", mx, nil, 404)
	// The limit: one more for mx, then no more.
	limit := 2
	mxUser.CertLimit = &limit
	if err := e.st.UpdateUser(context.Background(), mxUser); err != nil {
		t.Fatal(err)
	}
	if out, st := req(mx, "www", "www.adbraun.lol"); st != 200 && st != 202 {
		t.Errorf("second: %d %v", st, out)
	}
	if out, st := req(mx, "third", "x.adbraun.lol"); st != 400 || !strings.Contains(errMsg(out), "limit") {
		t.Errorf("over the limit: %d %v", st, out)
	}
	// The owner may delete theirs.
	e.do("DELETE", "/certificates/www", mx, nil, 200)
}

func jsonUnmarshal(b []byte, v any) error { return json.Unmarshal(b, v) }

// errMsg is an error answer's message.
func errMsg(out map[string]any) string {
	e, _ := out["error"].(map[string]any)
	m, _ := e["message"].(string)
	return m
}

// A private key goes back only over HTTPS or to this server itself.
func TestKeyTransport(t *testing.T) {
	e := newAPIEnv(t)
	for addr, want := range map[string]bool{"127.0.0.1:5000": true, "[::1]:5000": true, "192.0.2.7:5000": false} {
		r, _ := http.NewRequest("GET", "/x", nil)
		r.RemoteAddr = addr
		if ok, why := e.srv.keyTransport(r); ok != want {
			t.Errorf("%s: %v (%s)", addr, ok, why)
		}
	}
	r, _ := http.NewRequest("GET", "/x", nil)
	r.RemoteAddr, r.TLS = "192.0.2.7:5000", &tls.ConnectionState{}
	if ok, _ := e.srv.keyTransport(r); !ok {
		t.Error("HTTPS refused")
	}
}