package httpapi_test

import (
	"context"
	"encoding/json"
	"errors"
	"net/http"
	"net/http/httptest"
	"os"
	"path/filepath"
	"strings"
	"testing"

	"git.nianxx.cn/wangxuming/NianAIGC/backend/internal/httpapi"
	"git.nianxx.cn/wangxuming/NianAIGC/backend/internal/identity"
)

type passwordContract struct {
	Version                int    `json:"version"`
	Path                   string `json:"path"`
	Method                 string `json:"method"`
	LocalSessionTTLSeconds int64  `json:"localSessionTtlSeconds"`
	InputCases             []struct {
		Name             string         `json:"name"`
		Body             map[string]any `json:"body"`
		ExpectedRedirect string         `json:"expectedRedirect"`
	} `json:"inputCases"`
	SafeNextCases []struct {
		Input    *string `json:"input"`
		Expected string  `json:"expected"`
	} `json:"safeNextCases"`
	Success struct {
		TopLevelKeys            []string `json:"topLevelKeys"`
		PublicUserKeys          []string `json:"publicUserKeys"`
		ForbiddenSerializedKeys []string `json:"forbiddenSerializedKeys"`
	} `json:"success"`
	Errors struct {
		InvalidInput         fixtureError `json:"invalidInput"`
		InvalidCredentials   fixtureError `json:"invalidCredentials"`
		DisabledAccount      fixtureError `json:"disabledAccount"`
		DisabledOrganization fixtureError `json:"disabledOrganization"`
		LockedAccount        fixtureError `json:"lockedAccount"`
		RateLimited          fixtureError `json:"rateLimited"`
		Unconfigured         fixtureError `json:"unconfigured"`
	} `json:"errors"`
	RateLimit struct {
		AttemptsPerIP int `json:"attemptsPerIp"`
		WindowSeconds int `json:"windowSeconds"`
	} `json:"rateLimit"`
}

type fixtureError struct {
	Status int               `json:"status"`
	Body   map[string]string `json:"body"`
}

type passwordIssuerStub struct {
	session  identity.Session
	err      error
	commands []identity.LoginCommand
}

func (stub *passwordIssuerStub) Login(_ context.Context, command identity.LoginCommand) (identity.Session, error) {
	stub.commands = append(stub.commands, command)
	return stub.session, stub.err
}

func TestAuthPasswordConsumesSharedInputAndRedirectContract(t *testing.T) {
	contract := loadPasswordContract(t)
	for _, test := range contract.InputCases {
		t.Run(test.Name, func(t *testing.T) {
			issuer := &passwordIssuerStub{session: fixtureLoginSession()}
			handler := newPasswordHandler(t, issuer)
			body, _ := json.Marshal(test.Body)
			response := servePassword(handler, contract.Path, body, "198.51.100.1")

			if response.Code != http.StatusOK {
				t.Fatalf("status = %d body=%q, want 200", response.Code, response.Body.String())
			}
			if len(issuer.commands) != 1 || issuer.commands[0].Phone != "13800138000" || issuer.commands[0].Password != "TestPass123" {
				t.Fatalf("commands = %#v", issuer.commands)
			}
			var payload map[string]any
			if err := json.Unmarshal(response.Body.Bytes(), &payload); err != nil {
				t.Fatal(err)
			}
			if payload["redirectTo"] != test.ExpectedRedirect || payload["authMode"] != string(identity.AuthModeUser) || payload["ok"] != true {
				t.Fatalf("payload = %#v", payload)
			}
			assertKeySet(t, payload, contract.Success.TopLevelKeys)
			assertKeySet(t, payload["user"].(map[string]any), contract.Success.PublicUserKeys)
			for _, forbidden := range contract.Success.ForbiddenSerializedKeys {
				if strings.Contains(response.Body.String(), `"`+forbidden+`"`) {
					t.Fatalf("response leaked forbidden key %q: %s", forbidden, response.Body.String())
				}
			}
		})
	}
}

func TestAuthPasswordConsumesSharedSafeNextContract(t *testing.T) {
	contract := loadPasswordContract(t)
	for _, test := range contract.SafeNextCases {
		name := "null"
		var next any
		if test.Input != nil {
			name, next = *test.Input, *test.Input
		}
		t.Run(name, func(t *testing.T) {
			issuer := &passwordIssuerStub{session: fixtureLoginSession()}
			handler := newPasswordHandler(t, issuer)
			body, _ := json.Marshal(map[string]any{"phone": "13800138000", "password": "TestPass123", "next": next})
			response := servePassword(handler, contract.Path, body, "198.51.100.2")
			var payload struct {
				RedirectTo string `json:"redirectTo"`
			}
			if err := json.Unmarshal(response.Body.Bytes(), &payload); err != nil {
				t.Fatal(err)
			}
			if response.Code != http.StatusOK || payload.RedirectTo != test.Expected {
				t.Fatalf("response = %d %q, redirect=%q want %q", response.Code, response.Body.String(), payload.RedirectTo, test.Expected)
			}
		})
	}
}

func TestAuthPasswordConsumesSharedErrorContract(t *testing.T) {
	contract := loadPasswordContract(t)
	tests := []struct {
		name    string
		reason  identity.PasswordLoginFailure
		fixture fixtureError
	}{
		{"invalid input", identity.LoginFailureInvalidInput, contract.Errors.InvalidInput},
		{"credentials", identity.LoginFailureInvalidCredentials, contract.Errors.InvalidCredentials},
		{"disabled", identity.LoginFailureAccountDisabled, contract.Errors.DisabledAccount},
		{"invalid role", identity.LoginFailureInvalidRole, contract.Errors.DisabledOrganization},
		{"organization required", identity.LoginFailureOrganizationRequired, contract.Errors.DisabledOrganization},
		{"organization inactive", identity.LoginFailureOrganizationNotActive, contract.Errors.DisabledOrganization},
		{"locked", identity.LoginFailureAccountLocked, contract.Errors.LockedAccount},
	}
	for _, test := range tests {
		t.Run(test.name, func(t *testing.T) {
			issuer := &passwordIssuerStub{err: identity.NewPasswordLoginError(test.reason)}
			response := servePassword(newPasswordHandler(t, issuer), contract.Path, []byte(`{"phone":"13800138000","password":"bad"}`), "198.51.100.3")
			assertErrorFixture(t, response, test.fixture)
		})
	}

	unconfiguredIssuer := &passwordIssuerStub{}
	response := servePassword(newPasswordHandlerWithConfig(t, httpapi.PasswordAuthConfig{}, unconfiguredIssuer), contract.Path, []byte(`{}`), "198.51.100.4")
	assertErrorFixture(t, response, contract.Errors.Unconfigured)
	if len(unconfiguredIssuer.commands) != 0 {
		t.Fatalf("unconfigured issuer calls = %d, want 0", len(unconfiguredIssuer.commands))
	}
}

func TestAuthPasswordNullAndNonObjectJSONAreSafeInvalidInput(t *testing.T) {
	contract := loadPasswordContract(t)
	for _, body := range []string{"null", `[]`, `{not-json`} {
		issuer := &passwordIssuerStub{err: identity.NewPasswordLoginError(identity.LoginFailureInvalidInput)}
		response := servePassword(newPasswordHandler(t, issuer), contract.Path, []byte(body), "198.51.100.7")
		assertErrorFixture(t, response, contract.Errors.InvalidInput)
	}
}

func TestAuthPasswordRateLimitUsesForwardedIPAndClearsOnSuccess(t *testing.T) {
	contract := loadPasswordContract(t)
	issuer := &passwordIssuerStub{err: identity.NewPasswordLoginError(identity.LoginFailureInvalidCredentials)}
	handler := newPasswordHandler(t, issuer)
	requestBody := []byte(`{"phone":"13800138000","password":"bad"}`)
	for index := 0; index < contract.RateLimit.AttemptsPerIP; index++ {
		response := servePasswordWithHeaders(handler, contract.Path, requestBody, map[string]string{
			"X-Forwarded-For": "203.0.113.9, 10.0.0.4",
			"X-Real-IP":       "192.0.2.20",
		})
		if response.Code != contract.Errors.InvalidCredentials.Status {
			t.Fatalf("attempt %d status = %d", index+1, response.Code)
		}
	}
	limited := servePasswordWithHeaders(handler, contract.Path, requestBody, map[string]string{"X-Forwarded-For": "203.0.113.9"})
	assertErrorFixture(t, limited, contract.Errors.RateLimited)
	if len(issuer.commands) != contract.RateLimit.AttemptsPerIP {
		t.Fatalf("issuer calls = %d, want %d", len(issuer.commands), contract.RateLimit.AttemptsPerIP)
	}

	issuer.err = nil
	issuer.session = fixtureLoginSession()
	success := servePasswordWithHeaders(handler, contract.Path, []byte(`{"phone":"13800138000","password":"ok"}`), map[string]string{"X-Forwarded-For": "203.0.113.10"})
	if success.Code != http.StatusOK {
		t.Fatalf("success status = %d", success.Code)
	}
	issuer.err = identity.NewPasswordLoginError(identity.LoginFailureInvalidCredentials)
	afterSuccess := servePasswordWithHeaders(handler, contract.Path, requestBody, map[string]string{"X-Forwarded-For": "203.0.113.10"})
	if afterSuccess.Code != contract.Errors.InvalidCredentials.Status {
		t.Fatalf("after success status = %d", afterSuccess.Code)
	}
}

func TestAuthPasswordWritesTwentyFixtureCookiesAfterSuccessfulSign(t *testing.T) {
	contract := loadPasswordContract(t)
	cookie := loadPasswordSessionCookieContract(t)
	issuer := &passwordIssuerStub{session: fixtureLoginSession()}
	config := httpapi.PasswordAuthConfig{Configured: true, SessionSecret: cookie.Secret, PublicBaseURL: "https://app.example.test"}
	response := servePassword(newPasswordHandlerWithConfig(t, config, issuer), contract.Path, []byte(`{"phone":"13800138000","password":"ok"}`), "198.51.100.5")

	cookies := response.Result().Cookies()
	if response.Code != http.StatusOK || len(cookies) != cookie.Cookie.MaxChunks {
		t.Fatalf("status/cookies = %d/%d, want 200/%d", response.Code, len(cookies), cookie.Cookie.MaxChunks)
	}
	for index, got := range cookies {
		if got.Name != cookie.Cookie.ChunkNames[index] || got.Path != cookie.Cookie.Attributes.Path || got.HttpOnly != cookie.Cookie.Attributes.HTTPOnly || got.SameSite != http.SameSiteLaxMode || !got.Secure {
			t.Errorf("cookie %d = %#v", index, got)
		}
		if index == 0 {
			if got.Value == "" || got.Expires.Unix() != fixtureLoginSession().ExpiresAt {
				t.Errorf("session cookie = %#v", got)
			}
		} else if got.Value != cookie.Cookie.Clear.Value || got.MaxAge != -1 {
			t.Errorf("clear cookie %d = %#v", index, got)
		}
	}
}

func TestAuthPasswordInfrastructureFailureIsGenericAndWritesNoCookie(t *testing.T) {
	issuer := &passwordIssuerStub{err: errors.New("postgres password=secret")}
	response := servePassword(newPasswordHandler(t, issuer), "/api/auth/password", []byte(`{"phone":"13800138000","password":"ok"}`), "198.51.100.6")
	if response.Code != http.StatusInternalServerError || response.Body.String() != `{"error":"服务器内部错误。"}` || len(response.Result().Cookies()) != 0 {
		t.Fatalf("response = %d %q cookies=%d", response.Code, response.Body.String(), len(response.Result().Cookies()))
	}
}

func TestAuthPasswordMethodAndPathContract(t *testing.T) {
	contract := loadPasswordContract(t)
	handler := newPasswordHandler(t, &passwordIssuerStub{session: fixtureLoginSession()})
	tests := []struct {
		method, path string
		status       int
	}{
		{http.MethodGet, contract.Path, http.StatusMethodNotAllowed},
		{http.MethodPut, contract.Path, http.StatusMethodNotAllowed},
		{http.MethodOptions, contract.Path, http.StatusNoContent},
		{http.MethodPost, contract.Path + "/", http.StatusNotFound},
	}
	for _, test := range tests {
		response := httptest.NewRecorder()
		handler.ServeHTTP(response, httptest.NewRequest(test.method, test.path, nil))
		if response.Code != test.status || response.Body.Len() != 0 {
			t.Errorf("%s %s = %d %q", test.method, test.path, response.Code, response.Body.String())
		}
	}
}

func newPasswordHandler(t *testing.T, issuer httpapi.PasswordSessionIssuer) http.Handler {
	t.Helper()
	cookie := loadPasswordSessionCookieContract(t)
	return newPasswordHandlerWithConfig(t, httpapi.PasswordAuthConfig{Configured: true, SessionSecret: cookie.Secret}, issuer)
}

func newPasswordHandlerWithConfig(t *testing.T, config httpapi.PasswordAuthConfig, issuer httpapi.PasswordSessionIssuer) http.Handler {
	t.Helper()
	handler, err := httpapi.NewAuthPasswordHandler(config, issuer)
	if err != nil {
		t.Fatalf("NewAuthPasswordHandler() error = %v", err)
	}
	return handler
}

func servePassword(handler http.Handler, path string, body []byte, ip string) *httptest.ResponseRecorder {
	return servePasswordWithHeaders(handler, path, body, map[string]string{"X-Real-IP": ip})
}

func servePasswordWithHeaders(handler http.Handler, path string, body []byte, headers map[string]string) *httptest.ResponseRecorder {
	request := httptest.NewRequest(http.MethodPost, path, strings.NewReader(string(body)))
	request.Header.Set("Content-Type", "application/json")
	for key, value := range headers {
		request.Header.Set(key, value)
	}
	response := httptest.NewRecorder()
	handler.ServeHTTP(response, request)
	return response
}

func fixtureLoginSession() identity.Session {
	version := 7
	return identity.Session{Version: 1, AuthMode: identity.AuthModeUser, IssuedAt: 1_700_000_000, ExpiresAt: 1_700_086_400, SessionVersion: &version, User: identity.User{
		ID: "account-1", Subject: "account-1", Username: "13800138000", Phone: "13800138000", DisplayName: "张三", ClientID: "platform", OrganizationID: "org-1", OrganizationName: "组织一", Role: "user", Status: "active", Authorities: []string{"ROLE_USER"}, Scope: []string{},
	}}
}

func loadPasswordContract(t *testing.T) passwordContract {
	t.Helper()
	var fixture passwordContract
	loadHTTPFixture(t, "password-login-v1.json", &fixture)
	return fixture
}

type passwordSessionFixture struct {
	Secret string `json:"secret"`
	Cookie struct {
		MaxChunks  int      `json:"maxChunks"`
		ChunkNames []string `json:"chunkNames"`
		Attributes struct {
			HTTPOnly bool   `json:"httpOnly"`
			SameSite string `json:"sameSite"`
			Path     string `json:"path"`
		} `json:"attributes"`
		Clear struct {
			Value string `json:"value"`
		} `json:"clear"`
	} `json:"cookie"`
}

func loadPasswordSessionCookieContract(t *testing.T) passwordSessionFixture {
	t.Helper()
	var fixture passwordSessionFixture
	loadHTTPFixture(t, "session-cookie-v1.json", &fixture)
	return fixture
}

func loadHTTPFixture(t *testing.T, name string, target any) {
	t.Helper()
	data, err := os.ReadFile(filepath.Join("..", "..", "..", "contracts", "auth", name))
	if err != nil {
		t.Fatalf("read %s: %v", name, err)
	}
	if err := json.Unmarshal(data, target); err != nil {
		t.Fatalf("decode %s: %v", name, err)
	}
}

func assertKeySet(t *testing.T, got map[string]any, want []string) {
	t.Helper()
	keys := make([]string, 0, len(got))
	for key := range got {
		keys = append(keys, key)
	}
	if len(keys) != len(want) {
		t.Fatalf("keys = %v, want %v", keys, want)
	}
	for _, key := range want {
		if _, ok := got[key]; !ok {
			t.Fatalf("missing key %q in %v", key, keys)
		}
	}
}

func assertErrorFixture(t *testing.T, response *httptest.ResponseRecorder, fixture fixtureError) {
	t.Helper()
	want, _ := json.Marshal(fixture.Body)
	if response.Code != fixture.Status || strings.TrimSpace(response.Body.String()) != string(want) {
		t.Fatalf("response = %d %q, want %d %s", response.Code, response.Body.String(), fixture.Status, want)
	}
}