package api_test

import (
	"bytes"
	"context"
	"encoding/json"
	"io"
	"log/slog"
	"net/http"
	"net/http/httptest"
	"strconv"
	"testing"

	"github.com/gin-gonic/gin"
	"gorm.io/gorm"

	"ws_usernode/internal/api"
	"ws_usernode/internal/auth"
	"ws_usernode/internal/config"
	"ws_usernode/internal/model"
	"ws_usernode/internal/router"
	"ws_usernode/internal/service"
	"ws_usernode/internal/system"
)

// recordingMailer 捕获邮件，用于从重置邮件提取 token 等。
type recordingMailer struct {
	lastTo      string
	lastSubject string
	lastBody    string
}

func (m *recordingMailer) Send(_ context.Context, to, subject, body string) error {
	m.lastTo = to
	m.lastSubject = subject
	m.lastBody = body
	return nil
}

// testApp 完整组装的应用（SQLite 内存库 + dry-run 系统层）。
type testApp struct {
	r        http.Handler
	db       *gorm.DB
	captchas auth.CaptchaStore
	otps     auth.OTPStore
	mailer   *recordingMailer
}

func setupTestApp(t *testing.T) *testApp {
	t.Helper()
	gin.SetMode(gin.TestMode)
	db, err := model.Open("sqlite", ":memory:", false)
	if err != nil {
		t.Fatalf("open db: %v", err)
	}
	if err := model.Migrate(db); err != nil {
		t.Fatalf("migrate: %v", err)
	}
	cfg := config.Default()
	cfg.System.DryRun = true // 集成测试走 dry-run，不触碰真实系统账号

	sys := system.New(cfg.System)
	adminSvc := service.NewAdminService(db)
	userSvc := service.NewUserService(db, sys, cfg)
	auditSvc := service.NewAuditService(db)

	captchas := auth.NewMemoryCaptchaStore(cfg.Auth.CaptchaTTL)
	otps := auth.NewDBOTPStore(db, auth.DefaultMaxFailures, auth.DefaultFailureWin)
	sessions := auth.NewDBSessionStore(db)
	resets := auth.NewDBResetTokenStore(db)
	limiter := auth.NewRateLimiter(cfg.Auth.MaxLoginFailures, cfg.Auth.LockDuration)
	mailer := &recordingMailer{}
	log := slog.New(slog.NewTextHandler(io.Discard, nil))
	authSvc := service.NewAuthService(db, cfg, otps, captchas, sessions, resets, limiter, mailer, userSvc, adminSvc, auditSvc, log)

	h := api.New(cfg, authSvc, userSvc, auditSvc)
	r := router.New(cfg, h, sessions, log)

	if _, err := adminSvc.Create(context.Background(), "root", "Passw0rd", "root@example.com"); err != nil {
		t.Fatalf("seed admin: %v", err)
	}
	return &testApp{r: r, db: db, captchas: captchas, otps: otps, mailer: mailer}
}

// doJSON 发起 JSON 请求，返回 recorder。
func (a *testApp) doJSON(method, path string, body any, cookies ...*http.Cookie) *httptest.ResponseRecorder {
	var rdr io.Reader
	if body != nil {
		b, _ := json.Marshal(body)
		rdr = bytes.NewReader(b)
	}
	req := httptest.NewRequest(method, path, rdr)
	if body != nil {
		req.Header.Set("Content-Type", "application/json")
	}
	for _, c := range cookies {
		req.AddCookie(c)
	}
	w := httptest.NewRecorder()
	a.r.ServeHTTP(w, req)
	return w
}

func decodeBody(t *testing.T, w *httptest.ResponseRecorder) map[string]any {
	t.Helper()
	var m map[string]any
	if err := json.Unmarshal(w.Body.Bytes(), &m); err != nil {
		t.Fatalf("decode response %q: %v", w.Body.String(), err)
	}
	return m
}

func sessionCookie(t *testing.T, w *httptest.ResponseRecorder) *http.Cookie {
	t.Helper()
	for _, c := range w.Result().Cookies() {
		if c.Name == api.SessionCookieName {
			return c
		}
	}
	t.Fatalf("no session cookie in response")
	return nil
}

func TestAPICaptcha(t *testing.T) {
	app := setupTestApp(t)
	w := app.doJSON(http.MethodGet, "/api/v1/auth/captcha", nil)
	if w.Code != http.StatusOK {
		t.Fatalf("captcha status = %d, body=%s", w.Code, w.Body.String())
	}
	m := decodeBody(t, w)
	data := m["data"].(map[string]any)
	if data["captcha_id"] == "" || data["image"] == "" {
		t.Fatalf("captcha response missing fields: %v", data)
	}
}

func TestAPIAdminLoginRequiresSession(t *testing.T) {
	app := setupTestApp(t)
	// 未登录访问 /users 应 401
	w := app.doJSON(http.MethodGet, "/api/v1/users", nil)
	if w.Code != http.StatusUnauthorized {
		t.Fatalf("unauth users status = %d, want 401", w.Code)
	}
	// 错误密码 401
	w = app.doJSON(http.MethodPost, "/api/v1/auth/admin/login", map[string]string{"username": "root", "password": "bad"})
	if w.Code != http.StatusUnauthorized {
		t.Fatalf("bad login status = %d, want 401", w.Code)
	}
}

func TestAPIAdminUserLifecycle(t *testing.T) {
	app := setupTestApp(t)

	// 管理员登录
	w := app.doJSON(http.MethodPost, "/api/v1/auth/admin/login", map[string]string{"username": "root", "password": "Passw0rd"})
	if w.Code != http.StatusOK {
		t.Fatalf("admin login status = %d, body=%s", w.Code, w.Body.String())
	}
	ck := sessionCookie(t, w)

	// me
	w = app.doJSON(http.MethodGet, "/api/v1/auth/me", nil, ck)
	if w.Code != http.StatusOK {
		t.Fatalf("me status = %d", w.Code)
	}
	if m := decodeBody(t, w); m["data"].(map[string]any)["username"] != "root" {
		t.Fatalf("me body = %s", w.Body.String())
	}

	// 创建用户（dry-run 系统层）
	w = app.doJSON(http.MethodPost, "/api/v1/users", map[string]any{
		"username": "zhangsan", "email": "zs@example.com", "supervisor": "prof.li", "purpose": "科研", "ttl_days": 90,
	}, ck)
	if w.Code != http.StatusOK {
		t.Fatalf("create user status = %d, body=%s", w.Code, w.Body.String())
	}
	created := decodeBody(t, w)["data"].(map[string]any)
	id := uint(created["id"].(float64))
	if created["username"] != "ext_zhangsan" {
		t.Fatalf("created username = %v", created["username"])
	}

	// 列表
	w = app.doJSON(http.MethodGet, "/api/v1/users?status=active&page=1&page_size=10", nil, ck)
	if w.Code != http.StatusOK {
		t.Fatalf("list status = %d", w.Code)
	}
	list := decodeBody(t, w)["data"].(map[string]any)
	if list["total"].(float64) != 1 {
		t.Fatalf("list total = %v, want 1", list["total"])
	}

	// 详情
	w = app.doJSON(http.MethodGet, "/api/v1/users/"+itoa(id), nil, ck)
	if w.Code != http.StatusOK {
		t.Fatalf("get status = %d, body=%s", w.Code, w.Body.String())
	}

	// 更新（改邮箱）
	email := "zs-new@example.com"
	w = app.doJSON(http.MethodPatch, "/api/v1/users/"+itoa(id), map[string]any{"email": email}, ck)
	if w.Code != http.StatusOK {
		t.Fatalf("update status = %d, body=%s", w.Code, w.Body.String())
	}

	// 禁用 → 启用 → 延期
	for _, action := range []string{"disable", "enable", "extend"} {
		body := any(nil)
		if action == "extend" {
			body = map[string]any{"days": 30}
		}
		w = app.doJSON(http.MethodPost, "/api/v1/users/"+itoa(id)+"/"+action, body, ck)
		if w.Code != http.StatusOK {
			t.Fatalf("%s status = %d, body=%s", action, w.Code, w.Body.String())
		}
	}

	// 删除
	w = app.doJSON(http.MethodDelete, "/api/v1/users/"+itoa(id), nil, ck)
	if w.Code != http.StatusOK {
		t.Fatalf("delete status = %d, body=%s", w.Code, w.Body.String())
	}

	// 审计应已写入
	var n int64
	if err := app.db.Model(&model.AuditLog{}).Count(&n).Error; err != nil {
		t.Fatalf("audit count: %v", err)
	}
	if n < 7 {
		t.Fatalf("audit entries = %d, want >= 7", n)
	}
}

func TestAPIUserOTPLogin(t *testing.T) {
	app := setupTestApp(t)

	// 管理员登录并创建外部用户
	w := app.doJSON(http.MethodPost, "/api/v1/auth/admin/login", map[string]string{"username": "root", "password": "Passw0rd"})
	ck := sessionCookie(t, w)
	w = app.doJSON(http.MethodPost, "/api/v1/users", map[string]any{"username": "lisi", "email": "ls@example.com"}, ck)
	if w.Code != http.StatusOK {
		t.Fatalf("create user status = %d, body=%s", w.Code, w.Body.String())
	}

	// 生成图形验证码（直接经 store，模拟用户看到验证码）
	cap, err := app.captchas.New()
	if err != nil {
		t.Fatalf("captcha new: %v", err)
	}

	// 发送 OTP
	w = app.doJSON(http.MethodPost, "/api/v1/auth/otp/send", map[string]any{
		"username": "ext_lisi", "captcha_id": cap.ID, "captcha_code": cap.Text,
	})
	if w.Code != http.StatusOK {
		t.Fatalf("otp send status = %d, body=%s", w.Code, w.Body.String())
	}

	// CLI 通道取同一验证码
	code, err := app.otps.Current(context.Background(), "ext_lisi")
	if err != nil {
		t.Fatalf("otp current: %v", err)
	}

	// OTP 登录
	w = app.doJSON(http.MethodPost, "/api/v1/auth/otp/login", map[string]string{"username": "ext_lisi", "code": code})
	if w.Code != http.StatusOK {
		t.Fatalf("otp login status = %d, body=%s", w.Code, w.Body.String())
	}
	userCk := sessionCookie(t, w)

	// 外部用户 me
	w = app.doJSON(http.MethodGet, "/api/v1/auth/me", nil, userCk)
	if w.Code != http.StatusOK {
		t.Fatalf("user me status = %d", w.Code)
	}
	if m := decodeBody(t, w); m["data"].(map[string]any)["user_type"] != "user" {
		t.Fatalf("user me body = %s", w.Body.String())
	}

	// 外部用户访问 admin 路由应 403
	w = app.doJSON(http.MethodGet, "/api/v1/users", nil, userCk)
	if w.Code != http.StatusForbidden {
		t.Fatalf("user access admin status = %d, want 403", w.Code)
	}

	// 登出
	w = app.doJSON(http.MethodPost, "/api/v1/auth/logout", nil, userCk)
	if w.Code != http.StatusOK {
		t.Fatalf("logout status = %d", w.Code)
	}
	w = app.doJSON(http.MethodGet, "/api/v1/auth/me", nil, userCk)
	if w.Code != http.StatusUnauthorized {
		t.Fatalf("me after logout status = %d, want 401", w.Code)
	}
}

func TestAPIAdminForgotReset(t *testing.T) {
	app := setupTestApp(t)
	w := app.doJSON(http.MethodPost, "/api/v1/auth/admin/forgot", map[string]string{"username": "root"})
	if w.Code != http.StatusOK {
		t.Fatalf("forgot status = %d", w.Code)
	}
	if app.mailer.lastTo != "root@example.com" {
		t.Fatalf("reset mail to = %q", app.mailer.lastTo)
	}
	idx := bytes.Index([]byte(app.mailer.lastBody), []byte("token="))
	if idx < 0 {
		t.Fatalf("reset link missing token: %s", app.mailer.lastBody)
	}
	token := app.mailer.lastBody[idx+6:]
	token = token[:bytes.IndexByte([]byte(token), '\n')]
	w = app.doJSON(http.MethodPost, "/api/v1/auth/admin/reset", map[string]string{"token": token, "new_password": "NewPassw0rd"})
	if w.Code != http.StatusOK {
		t.Fatalf("reset status = %d, body=%s", w.Code, w.Body.String())
	}
	// 新密码可登录
	w = app.doJSON(http.MethodPost, "/api/v1/auth/admin/login", map[string]string{"username": "root", "password": "NewPassw0rd"})
	if w.Code != http.StatusOK {
		t.Fatalf("login with new password status = %d", w.Code)
	}
}

func itoa(u uint) string {
	return strconv.FormatUint(uint64(u), 10)
}