package api

import (
	"bytes"
	"context"
	"crypto/tls"
	"crypto/x509"
	"encoding/json"
	"encoding/pem"
	"fmt"
	"io"
	"net/http"
	"net/http/httptest"
	"net/url"
	"testing"
	"time"

	"github.com/go-chi/chi"
	"github.com/google/go-cmp/cmp"
	"github.com/pkg/errors"
	"github.com/smallstep/assert"
	"github.com/smallstep/certificates/acme"
	"go.step.sm/crypto/jose"
	"go.step.sm/crypto/pemutil"
)

type mockClient struct {
	get       func(url string) (*http.Response, error)
	lookupTxt func(name string) ([]string, error)
	tlsDial   func(network, addr string, config *tls.Config) (*tls.Conn, error)
}

func (m *mockClient) Get(u string) (*http.Response, error)    { return m.get(u) }
func (m *mockClient) LookupTxt(name string) ([]string, error) { return m.lookupTxt(name) }
func (m *mockClient) TLSDial(network, addr string, config *tls.Config) (*tls.Conn, error) {
	return m.tlsDial(network, addr, config)
}

func mockMustAuthority(t *testing.T, a acme.CertificateAuthority) {
	t.Helper()
	fn := mustAuthority
	t.Cleanup(func() {
		mustAuthority = fn
	})
	mustAuthority = func(ctx context.Context) acme.CertificateAuthority {
		return a
	}
}

func TestHandler_GetNonce(t *testing.T) {
	tests := []struct {
		name       string
		statusCode int
	}{
		{"GET", 204},
		{"HEAD", 200},
	}

	// Request with chi context
	req := httptest.NewRequest("GET", "http://ca.smallstep.com/nonce", nil)

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			// h := &Handler{}
			w := httptest.NewRecorder()
			req.Method = tt.name
			GetNonce(w, req)
			res := w.Result()

			if res.StatusCode != tt.statusCode {
				t.Errorf("Handler.GetNonce StatusCode = %d, wants %d", res.StatusCode, tt.statusCode)
			}
		})
	}
}

func TestHandler_GetDirectory(t *testing.T) {
	linker := acme.NewLinker("ca.smallstep.com", "acme")
	_ = linker
	type test struct {
		ctx        context.Context
		statusCode int
		dir        Directory
		err        *acme.Error
	}
	var tests = map[string]func(t *testing.T) test{
		"fail/no-provisioner": func(t *testing.T) test {
			return test{
				ctx:        context.Background(),
				statusCode: 500,
				err:        acme.NewErrorISE("provisioner is not in context"),
			}
		},
		"fail/different-provisioner": func(t *testing.T) test {
			ctx := acme.NewProvisionerContext(context.Background(), &fakeProvisioner{})
			return test{
				ctx:        ctx,
				statusCode: 500,
				err:        acme.NewErrorISE("provisioner in context is not an ACME provisioner"),
			}
		},
		"ok": func(t *testing.T) test {
			prov := newProv()
			provName := url.PathEscape(prov.GetName())
			baseURL := &url.URL{Scheme: "https", Host: "test.ca.smallstep.com"}
			ctx := acme.NewProvisionerContext(context.Background(), prov)
			expDir := Directory{
				NewNonce:   fmt.Sprintf("%s/acme/%s/new-nonce", baseURL.String(), provName),
				NewAccount: fmt.Sprintf("%s/acme/%s/new-account", baseURL.String(), provName),
				NewOrder:   fmt.Sprintf("%s/acme/%s/new-order", baseURL.String(), provName),
				RevokeCert: fmt.Sprintf("%s/acme/%s/revoke-cert", baseURL.String(), provName),
				KeyChange:  fmt.Sprintf("%s/acme/%s/key-change", baseURL.String(), provName),
			}
			return test{
				ctx:        ctx,
				dir:        expDir,
				statusCode: 200,
			}
		},
		"ok/eab-required": func(t *testing.T) test {
			prov := newACMEProv(t)
			prov.RequireEAB = true
			provName := url.PathEscape(prov.GetName())
			baseURL := &url.URL{Scheme: "https", Host: "test.ca.smallstep.com"}
			ctx := acme.NewProvisionerContext(context.Background(), prov)
			expDir := Directory{
				NewNonce:   fmt.Sprintf("%s/acme/%s/new-nonce", baseURL.String(), provName),
				NewAccount: fmt.Sprintf("%s/acme/%s/new-account", baseURL.String(), provName),
				NewOrder:   fmt.Sprintf("%s/acme/%s/new-order", baseURL.String(), provName),
				RevokeCert: fmt.Sprintf("%s/acme/%s/revoke-cert", baseURL.String(), provName),
				KeyChange:  fmt.Sprintf("%s/acme/%s/key-change", baseURL.String(), provName),
				Meta: Meta{
					ExternalAccountRequired: true,
				},
			}
			return test{
				ctx:        ctx,
				dir:        expDir,
				statusCode: 200,
			}
		},
	}
	for name, run := range tests {
		tc := run(t)
		t.Run(name, func(t *testing.T) {
			ctx := acme.NewLinkerContext(tc.ctx, acme.NewLinker("test.ca.smallstep.com", "acme"))
			req := httptest.NewRequest("GET", "/foo/bar", nil)
			req = req.WithContext(ctx)
			w := httptest.NewRecorder()
			GetDirectory(w, req)
			res := w.Result()

			assert.Equals(t, res.StatusCode, tc.statusCode)

			body, err := io.ReadAll(res.Body)
			res.Body.Close()
			assert.FatalError(t, err)

			if res.StatusCode >= 400 && assert.NotNil(t, tc.err) {
				var ae acme.Error
				assert.FatalError(t, json.Unmarshal(bytes.TrimSpace(body), &ae))

				assert.Equals(t, ae.Type, tc.err.Type)
				assert.Equals(t, ae.Detail, tc.err.Detail)
				assert.Equals(t, ae.Identifier, tc.err.Identifier)
				assert.Equals(t, ae.Subproblems, tc.err.Subproblems)
				assert.Equals(t, res.Header["Content-Type"], []string{"application/problem+json"})
			} else {
				var dir Directory
				json.Unmarshal(bytes.TrimSpace(body), &dir)
				if !cmp.Equal(tc.dir, dir) {
					t.Errorf("GetDirectory() diff =\n%s", cmp.Diff(tc.dir, dir))
				}
				assert.Equals(t, res.Header["Content-Type"], []string{"application/json"})
			}
		})
	}
}

func TestHandler_GetAuthorization(t *testing.T) {
	expiry := time.Now().UTC().Add(6 * time.Hour)
	az := acme.Authorization{
		ID:        "authzID",
		AccountID: "accID",
		Identifier: acme.Identifier{
			Type:  "dns",
			Value: "example.com",
		},
		Status:    "pending",
		ExpiresAt: expiry,
		Wildcard:  false,
		Challenges: []*acme.Challenge{
			{
				Type:   "http-01",
				Status: "pending",
				Token:  "tok2",
				URL:    "https://ca.smallstep.com/acme/challenge/chHTTPID",
				ID:     "chHTTP01ID",
			},
			{
				Type:   "dns-01",
				Status: "pending",
				Token:  "tok2",
				URL:    "https://ca.smallstep.com/acme/challenge/chDNSID",
				ID:     "chDNSID",
			},
		},
	}
	prov := newProv()
	provName := url.PathEscape(prov.GetName())
	baseURL := &url.URL{Scheme: "https", Host: "test.ca.smallstep.com"}

	// Request with chi context
	chiCtx := chi.NewRouteContext()
	chiCtx.URLParams.Add("authzID", az.ID)
	u := fmt.Sprintf("%s/acme/%s/authz/%s",
		baseURL.String(), provName, az.ID)

	type test struct {
		db         acme.DB
		ctx        context.Context
		statusCode int
		err        *acme.Error
	}
	var tests = map[string]func(t *testing.T) test{
		"fail/no-account": func(t *testing.T) test {
			return test{
				db:         &acme.MockDB{},
				ctx:        context.Background(),
				statusCode: 400,
				err:        acme.NewError(acme.ErrorAccountDoesNotExistType, "account does not exist"),
			}
		},
		"fail/nil-account": func(t *testing.T) test {
			ctx := acme.NewProvisionerContext(context.Background(), prov)
			ctx = context.WithValue(ctx, accContextKey, nil)
			return test{
				db:         &acme.MockDB{},
				ctx:        ctx,
				statusCode: 400,
				err:        acme.NewError(acme.ErrorAccountDoesNotExistType, "account does not exist"),
			}
		},
		"fail/db.GetAuthorization-error": func(t *testing.T) test {
			acc := &acme.Account{ID: "accID"}
			ctx := context.WithValue(context.Background(), accContextKey, acc)
			ctx = context.WithValue(ctx, chi.RouteCtxKey, chiCtx)
			return test{
				db: &acme.MockDB{
					MockError: acme.NewErrorISE("force"),
				},
				ctx:        ctx,
				statusCode: 500,
				err:        acme.NewErrorISE("force"),
			}
		},
		"fail/account-id-mismatch": func(t *testing.T) test {
			acc := &acme.Account{ID: "accID"}
			ctx := context.WithValue(context.Background(), accContextKey, acc)
			ctx = context.WithValue(ctx, chi.RouteCtxKey, chiCtx)
			return test{
				db: &acme.MockDB{
					MockGetAuthorization: func(ctx context.Context, id string) (*acme.Authorization, error) {
						assert.Equals(t, id, az.ID)
						return &acme.Authorization{
							AccountID: "foo",
						}, nil
					},
				},
				ctx:        ctx,
				statusCode: 401,
				err:        acme.NewError(acme.ErrorUnauthorizedType, "account id mismatch"),
			}
		},
		"fail/db.UpdateAuthorization-error": func(t *testing.T) test {
			acc := &acme.Account{ID: "accID"}
			ctx := context.WithValue(context.Background(), accContextKey, acc)
			ctx = context.WithValue(ctx, chi.RouteCtxKey, chiCtx)
			return test{
				db: &acme.MockDB{
					MockGetAuthorization: func(ctx context.Context, id string) (*acme.Authorization, error) {
						assert.Equals(t, id, az.ID)
						return &acme.Authorization{
							AccountID: "accID",
							Status:    acme.StatusPending,
							ExpiresAt: time.Now().Add(-1 * time.Hour),
						}, nil
					},
					MockUpdateAuthorization: func(ctx context.Context, az *acme.Authorization) error {
						assert.Equals(t, az.Status, acme.StatusInvalid)
						return acme.NewErrorISE("force")
					},
				},
				ctx:        ctx,
				statusCode: 500,
				err:        acme.NewErrorISE("force"),
			}
		},
		"ok": func(t *testing.T) test {
			acc := &acme.Account{ID: "accID"}
			ctx := acme.NewProvisionerContext(context.Background(), prov)
			ctx = context.WithValue(ctx, accContextKey, acc)
			ctx = context.WithValue(ctx, chi.RouteCtxKey, chiCtx)
			return test{
				db: &acme.MockDB{
					MockGetAuthorization: func(ctx context.Context, id string) (*acme.Authorization, error) {
						assert.Equals(t, id, az.ID)
						return &az, nil
					},
				},
				ctx:        ctx,
				statusCode: 200,
			}
		},
	}
	for name, run := range tests {
		tc := run(t)
		t.Run(name, func(t *testing.T) {
			ctx := acme.NewContext(tc.ctx, tc.db, nil, acme.NewLinker("test.ca.smallstep.com", "acme"), nil)
			req := httptest.NewRequest("GET", "/foo/bar", nil)
			req = req.WithContext(ctx)
			w := httptest.NewRecorder()
			GetAuthorization(w, req)
			res := w.Result()

			assert.Equals(t, res.StatusCode, tc.statusCode)

			body, err := io.ReadAll(res.Body)
			res.Body.Close()
			assert.FatalError(t, err)

			if res.StatusCode >= 400 && assert.NotNil(t, tc.err) {
				var ae acme.Error
				assert.FatalError(t, json.Unmarshal(bytes.TrimSpace(body), &ae))

				assert.Equals(t, ae.Type, tc.err.Type)
				assert.Equals(t, ae.Detail, tc.err.Detail)
				assert.Equals(t, ae.Identifier, tc.err.Identifier)
				assert.Equals(t, ae.Subproblems, tc.err.Subproblems)
				assert.Equals(t, res.Header["Content-Type"], []string{"application/problem+json"})
			} else {
				//var gotAz acme.Authz
				//assert.FatalError(t, json.Unmarshal(bytes.TrimSpace(body), &gotAz))
				expB, err := json.Marshal(az)
				assert.FatalError(t, err)
				assert.Equals(t, bytes.TrimSpace(body), expB)
				assert.Equals(t, res.Header["Location"], []string{u})
				assert.Equals(t, res.Header["Content-Type"], []string{"application/json"})
			}
		})
	}
}

func TestHandler_GetCertificate(t *testing.T) {
	leaf, err := pemutil.ReadCertificate("../../authority/testdata/certs/foo.crt")
	assert.FatalError(t, err)
	inter, err := pemutil.ReadCertificate("../../authority/testdata/certs/intermediate_ca.crt")
	assert.FatalError(t, err)
	root, err := pemutil.ReadCertificate("../../authority/testdata/certs/root_ca.crt")
	assert.FatalError(t, err)

	certBytes := append(pem.EncodeToMemory(&pem.Block{
		Type:  "CERTIFICATE",
		Bytes: leaf.Raw,
	}), pem.EncodeToMemory(&pem.Block{
		Type:  "CERTIFICATE",
		Bytes: inter.Raw,
	})...)
	certBytes = append(certBytes, pem.EncodeToMemory(&pem.Block{
		Type:  "CERTIFICATE",
		Bytes: root.Raw,
	})...)
	certID := "certID"

	prov := newProv()
	provName := url.PathEscape(prov.GetName())
	baseURL := &url.URL{Scheme: "https", Host: "test.ca.smallstep.com"}
	// Request with chi context
	chiCtx := chi.NewRouteContext()
	chiCtx.URLParams.Add("certID", certID)
	u := fmt.Sprintf("%s/acme/%s/certificate/%s",
		baseURL.String(), provName, certID)

	type test struct {
		db         acme.DB
		ctx        context.Context
		statusCode int
		err        *acme.Error
	}
	var tests = map[string]func(t *testing.T) test{
		"fail/no-account": func(t *testing.T) test {
			return test{
				db:         &acme.MockDB{},
				ctx:        context.Background(),
				statusCode: 400,
				err:        acme.NewError(acme.ErrorAccountDoesNotExistType, "account does not exist"),
			}
		},
		"fail/nil-account": func(t *testing.T) test {
			ctx := context.WithValue(context.Background(), accContextKey, nil)
			return test{
				db:         &acme.MockDB{},
				ctx:        ctx,
				statusCode: 400,
				err:        acme.NewError(acme.ErrorAccountDoesNotExistType, "account does not exist"),
			}
		},
		"fail/db.GetCertificate-error": func(t *testing.T) test {
			acc := &acme.Account{ID: "accID"}
			ctx := context.WithValue(context.Background(), accContextKey, acc)
			ctx = context.WithValue(ctx, chi.RouteCtxKey, chiCtx)
			return test{
				db: &acme.MockDB{
					MockError: acme.NewErrorISE("force"),
				},
				ctx:        ctx,
				statusCode: 500,
				err:        acme.NewErrorISE("force"),
			}
		},
		"fail/account-id-mismatch": func(t *testing.T) test {
			acc := &acme.Account{ID: "accID"}
			ctx := context.WithValue(context.Background(), accContextKey, acc)
			ctx = context.WithValue(ctx, chi.RouteCtxKey, chiCtx)
			return test{
				db: &acme.MockDB{
					MockGetCertificate: func(ctx context.Context, id string) (*acme.Certificate, error) {
						assert.Equals(t, id, certID)
						return &acme.Certificate{AccountID: "foo"}, nil
					},
				},
				ctx:        ctx,
				statusCode: 401,
				err:        acme.NewError(acme.ErrorUnauthorizedType, "account id mismatch"),
			}
		},
		"ok": func(t *testing.T) test {
			acc := &acme.Account{ID: "accID"}
			ctx := context.WithValue(context.Background(), accContextKey, acc)
			ctx = context.WithValue(ctx, chi.RouteCtxKey, chiCtx)
			return test{
				db: &acme.MockDB{
					MockGetCertificate: func(ctx context.Context, id string) (*acme.Certificate, error) {
						assert.Equals(t, id, certID)
						return &acme.Certificate{
							AccountID:     "accID",
							OrderID:       "ordID",
							Leaf:          leaf,
							Intermediates: []*x509.Certificate{inter, root},
							ID:            id,
						}, nil
					},
				},
				ctx:        ctx,
				statusCode: 200,
			}
		},
	}
	for name, run := range tests {
		tc := run(t)
		t.Run(name, func(t *testing.T) {
			ctx := acme.NewDatabaseContext(tc.ctx, tc.db)
			req := httptest.NewRequest("GET", u, nil)
			req = req.WithContext(ctx)
			w := httptest.NewRecorder()
			GetCertificate(w, req)
			res := w.Result()

			assert.Equals(t, res.StatusCode, tc.statusCode)

			body, err := io.ReadAll(res.Body)
			res.Body.Close()
			assert.FatalError(t, err)

			if res.StatusCode >= 400 && assert.NotNil(t, tc.err) {
				var ae acme.Error
				assert.FatalError(t, json.Unmarshal(bytes.TrimSpace(body), &ae))

				assert.Equals(t, ae.Type, tc.err.Type)
				assert.HasPrefix(t, ae.Detail, tc.err.Detail)
				assert.Equals(t, ae.Identifier, tc.err.Identifier)
				assert.Equals(t, ae.Subproblems, tc.err.Subproblems)
				assert.Equals(t, res.Header["Content-Type"], []string{"application/problem+json"})
			} else {
				assert.Equals(t, bytes.TrimSpace(body), bytes.TrimSpace(certBytes))
				assert.Equals(t, res.Header["Content-Type"], []string{"application/pem-certificate-chain; charset=utf-8"})
			}
		})
	}
}

func TestHandler_GetChallenge(t *testing.T) {
	chiCtx := chi.NewRouteContext()
	chiCtx.URLParams.Add("chID", "chID")
	chiCtx.URLParams.Add("authzID", "authzID")
	prov := newProv()
	provName := url.PathEscape(prov.GetName())

	baseURL := &url.URL{Scheme: "https", Host: "test.ca.smallstep.com"}

	u := fmt.Sprintf("%s/acme/%s/challenge/%s/%s",
		baseURL.String(), provName, "authzID", "chID")

	type test struct {
		db         acme.DB
		vc         acme.Client
		ctx        context.Context
		statusCode int
		ch         *acme.Challenge
		err        *acme.Error
	}
	var tests = map[string]func(t *testing.T) test{
		"fail/no-account": func(t *testing.T) test {
			return test{
				db:         &acme.MockDB{},
				ctx:        context.Background(),
				statusCode: 400,
				err:        acme.NewError(acme.ErrorAccountDoesNotExistType, "account does not exist"),
			}
		},
		"fail/nil-account": func(t *testing.T) test {
			return test{
				db:         &acme.MockDB{},
				ctx:        context.WithValue(context.Background(), accContextKey, nil),
				statusCode: 400,
				err:        acme.NewError(acme.ErrorAccountDoesNotExistType, "account does not exist"),
			}
		},
		"fail/no-payload": func(t *testing.T) test {
			acc := &acme.Account{ID: "accID"}
			ctx := context.WithValue(context.Background(), accContextKey, acc)
			return test{
				db:         &acme.MockDB{},
				ctx:        ctx,
				statusCode: 500,
				err:        acme.NewErrorISE("payload expected in request context"),
			}
		},
		"fail/nil-payload": func(t *testing.T) test {
			acc := &acme.Account{ID: "accID"}
			ctx := acme.NewProvisionerContext(context.Background(), prov)
			ctx = context.WithValue(ctx, accContextKey, acc)
			ctx = context.WithValue(ctx, payloadContextKey, nil)
			return test{
				db:         &acme.MockDB{},
				ctx:        ctx,
				statusCode: 500,
				err:        acme.NewErrorISE("payload expected in request context"),
			}
		},
		"fail/db.GetChallenge-error": func(t *testing.T) test {
			acc := &acme.Account{ID: "accID"}
			ctx := acme.NewProvisionerContext(context.Background(), prov)
			ctx = context.WithValue(ctx, accContextKey, acc)
			ctx = context.WithValue(ctx, payloadContextKey, &payloadInfo{isEmptyJSON: true})
			ctx = context.WithValue(ctx, chi.RouteCtxKey, chiCtx)
			return test{
				db: &acme.MockDB{
					MockGetChallenge: func(ctx context.Context, chID, azID string) (*acme.Challenge, error) {
						assert.Equals(t, chID, "chID")
						assert.Equals(t, azID, "authzID")
						return nil, acme.NewErrorISE("force")
					},
				},
				ctx:        ctx,
				statusCode: 500,
				err:        acme.NewErrorISE("force"),
			}
		},
		"fail/account-id-mismatch": func(t *testing.T) test {
			acc := &acme.Account{ID: "accID"}
			ctx := acme.NewProvisionerContext(context.Background(), prov)
			ctx = context.WithValue(ctx, accContextKey, acc)
			ctx = context.WithValue(ctx, payloadContextKey, &payloadInfo{isEmptyJSON: true})
			ctx = context.WithValue(ctx, chi.RouteCtxKey, chiCtx)
			return test{
				db: &acme.MockDB{
					MockGetChallenge: func(ctx context.Context, chID, azID string) (*acme.Challenge, error) {
						assert.Equals(t, chID, "chID")
						assert.Equals(t, azID, "authzID")
						return &acme.Challenge{AccountID: "foo"}, nil
					},
				},
				ctx:        ctx,
				statusCode: 401,
				err:        acme.NewError(acme.ErrorUnauthorizedType, "accout id mismatch"),
			}
		},
		"fail/no-jwk": func(t *testing.T) test {
			acc := &acme.Account{ID: "accID"}
			ctx := acme.NewProvisionerContext(context.Background(), prov)
			ctx = context.WithValue(ctx, accContextKey, acc)
			ctx = context.WithValue(ctx, payloadContextKey, &payloadInfo{isEmptyJSON: true})
			ctx = context.WithValue(ctx, chi.RouteCtxKey, chiCtx)
			return test{
				db: &acme.MockDB{
					MockGetChallenge: func(ctx context.Context, chID, azID string) (*acme.Challenge, error) {
						assert.Equals(t, chID, "chID")
						assert.Equals(t, azID, "authzID")
						return &acme.Challenge{AccountID: "accID"}, nil
					},
				},
				ctx:        ctx,
				statusCode: 500,
				err:        acme.NewErrorISE("missing jwk"),
			}
		},
		"fail/nil-jwk": func(t *testing.T) test {
			acc := &acme.Account{ID: "accID"}
			ctx := acme.NewProvisionerContext(context.Background(), prov)
			ctx = context.WithValue(ctx, accContextKey, acc)
			ctx = context.WithValue(ctx, payloadContextKey, &payloadInfo{isEmptyJSON: true})
			ctx = context.WithValue(ctx, jwkContextKey, nil)
			ctx = context.WithValue(ctx, chi.RouteCtxKey, chiCtx)
			return test{
				db: &acme.MockDB{
					MockGetChallenge: func(ctx context.Context, chID, azID string) (*acme.Challenge, error) {
						assert.Equals(t, chID, "chID")
						assert.Equals(t, azID, "authzID")
						return &acme.Challenge{AccountID: "accID"}, nil
					},
				},
				ctx:        ctx,
				statusCode: 500,
				err:        acme.NewErrorISE("nil jwk"),
			}
		},
		"fail/validate-challenge-error": func(t *testing.T) test {
			acc := &acme.Account{ID: "accID"}
			ctx := acme.NewProvisionerContext(context.Background(), prov)
			ctx = context.WithValue(ctx, accContextKey, acc)
			ctx = context.WithValue(ctx, payloadContextKey, &payloadInfo{isEmptyJSON: true})
			_jwk, err := jose.GenerateJWK("EC", "P-256", "ES256", "sig", "", 0)
			assert.FatalError(t, err)
			_pub := _jwk.Public()
			ctx = context.WithValue(ctx, jwkContextKey, &_pub)
			ctx = context.WithValue(ctx, chi.RouteCtxKey, chiCtx)
			return test{
				db: &acme.MockDB{
					MockGetChallenge: func(ctx context.Context, chID, azID string) (*acme.Challenge, error) {
						assert.Equals(t, chID, "chID")
						assert.Equals(t, azID, "authzID")
						return &acme.Challenge{
							Status:    acme.StatusPending,
							Type:      acme.HTTP01,
							AccountID: "accID",
						}, nil
					},
					MockUpdateChallenge: func(ctx context.Context, ch *acme.Challenge) error {
						assert.Equals(t, ch.Status, acme.StatusPending)
						assert.Equals(t, ch.Type, acme.HTTP01)
						assert.Equals(t, ch.AccountID, "accID")
						assert.Equals(t, ch.AuthorizationID, "authzID")
						assert.HasSuffix(t, ch.Error.Type, acme.ErrorConnectionType.String())
						return acme.NewErrorISE("force")
					},
				},
				vc: &mockClient{
					get: func(string) (*http.Response, error) {
						return nil, errors.New("force")
					},
				},
				ctx:        ctx,
				statusCode: 500,
				err:        acme.NewErrorISE("force"),
			}
		},
		"ok": func(t *testing.T) test {
			acc := &acme.Account{ID: "accID"}
			ctx := acme.NewProvisionerContext(context.Background(), prov)
			ctx = context.WithValue(ctx, accContextKey, acc)
			ctx = context.WithValue(ctx, payloadContextKey, &payloadInfo{isEmptyJSON: true})
			_jwk, err := jose.GenerateJWK("EC", "P-256", "ES256", "sig", "", 0)
			assert.FatalError(t, err)
			_pub := _jwk.Public()
			ctx = context.WithValue(ctx, jwkContextKey, &_pub)
			ctx = context.WithValue(ctx, chi.RouteCtxKey, chiCtx)
			return test{
				db: &acme.MockDB{
					MockGetChallenge: func(ctx context.Context, chID, azID string) (*acme.Challenge, error) {
						assert.Equals(t, chID, "chID")
						assert.Equals(t, azID, "authzID")
						return &acme.Challenge{
							ID:        "chID",
							Status:    acme.StatusPending,
							Type:      acme.HTTP01,
							AccountID: "accID",
						}, nil
					},
					MockUpdateChallenge: func(ctx context.Context, ch *acme.Challenge) error {
						assert.Equals(t, ch.Status, acme.StatusPending)
						assert.Equals(t, ch.Type, acme.HTTP01)
						assert.Equals(t, ch.AccountID, "accID")
						assert.Equals(t, ch.AuthorizationID, "authzID")
						assert.HasSuffix(t, ch.Error.Type, acme.ErrorConnectionType.String())
						return nil
					},
				},
				ch: &acme.Challenge{
					ID:              "chID",
					Status:          acme.StatusPending,
					AuthorizationID: "authzID",
					Type:            acme.HTTP01,
					AccountID:       "accID",
					URL:             u,
					Error:           acme.NewError(acme.ErrorConnectionType, "force"),
				},
				vc: &mockClient{
					get: func(string) (*http.Response, error) {
						return nil, errors.New("force")
					},
				},
				ctx:        ctx,
				statusCode: 200,
			}
		},
	}
	for name, run := range tests {
		tc := run(t)
		t.Run(name, func(t *testing.T) {
			ctx := acme.NewContext(tc.ctx, tc.db, nil, acme.NewLinker("test.ca.smallstep.com", "acme"), nil)
			req := httptest.NewRequest("GET", u, nil)
			req = req.WithContext(ctx)
			w := httptest.NewRecorder()
			GetChallenge(w, req)
			res := w.Result()

			assert.Equals(t, res.StatusCode, tc.statusCode)

			body, err := io.ReadAll(res.Body)
			res.Body.Close()
			assert.FatalError(t, err)

			if res.StatusCode >= 400 && assert.NotNil(t, tc.err) {
				var ae acme.Error
				assert.FatalError(t, json.Unmarshal(bytes.TrimSpace(body), &ae))

				assert.Equals(t, ae.Type, tc.err.Type)
				assert.Equals(t, ae.Detail, tc.err.Detail)
				assert.Equals(t, ae.Identifier, tc.err.Identifier)
				assert.Equals(t, ae.Subproblems, tc.err.Subproblems)
				assert.Equals(t, res.Header["Content-Type"], []string{"application/problem+json"})
			} else {
				expB, err := json.Marshal(tc.ch)
				assert.FatalError(t, err)
				assert.Equals(t, bytes.TrimSpace(body), expB)
				assert.Equals(t, res.Header["Link"], []string{fmt.Sprintf("<%s/acme/%s/authz/%s>;rel=\"up\"", baseURL, provName, "authzID")})
				assert.Equals(t, res.Header["Location"], []string{u})
				assert.Equals(t, res.Header["Content-Type"], []string{"application/json"})
			}
		})
	}
}