/*
server_test.go - Web服务器测试文件
测试HTTP服务器和API的各种功能
*/

package main

import (
	"bytes"
	"encoding/json"
	"fmt"
	"net/http"
	"net/http/httptest"
	"testing"

	"webserver/models"
	"webserver/server"
)

// TestHealthHandler 测试健康检查处理器
func TestHealthHandler(t *testing.T) {
	req, err := http.NewRequest("GET", "/health", nil)
	if err != nil {
		t.Fatal(err)
	}

	rr := httptest.NewRecorder()
	handler := http.HandlerFunc(server.HealthHandler)

	handler.ServeHTTP(rr, req)

	// 检查状态码
	if status := rr.Code; status != http.StatusOK {
		t.Errorf("处理器返回错误状态码: got %v want %v", status, http.StatusOK)
	}

	// 检查响应内容类型
	expected := "application/json"
	if ct := rr.Header().Get("Content-Type"); ct != expected {
		t.Errorf("处理器返回错误内容类型: got %v want %v", ct, expected)
	}

	// 检查响应体
	var response server.HealthResponse
	if err := json.Unmarshal(rr.Body.Bytes(), &response); err != nil {
		t.Errorf("无法解析响应JSON: %v", err)
	}

	if response.Status != "healthy" {
		t.Errorf("期望状态为 'healthy', 实际为 '%s'", response.Status)
	}
}

// TestGetUsersHandler 测试获取用户列表处理器
func TestGetUsersHandler(t *testing.T) {
	req, err := http.NewRequest("GET", "/api/users", nil)
	if err != nil {
		t.Fatal(err)
	}

	rr := httptest.NewRecorder()
	handler := http.HandlerFunc(server.GetUsersHandler)

	handler.ServeHTTP(rr, req)

	// 检查状态码
	if status := rr.Code; status != http.StatusOK {
		t.Errorf("处理器返回错误状态码: got %v want %v", status, http.StatusOK)
	}

	// 检查响应内容类型
	expected := "application/json"
	if ct := rr.Header().Get("Content-Type"); ct != expected {
		t.Errorf("处理器返回错误内容类型: got %v want %v", ct, expected)
	}

	// 检查响应体
	var response server.Response
	if err := json.Unmarshal(rr.Body.Bytes(), &response); err != nil {
		t.Errorf("无法解析响应JSON: %v", err)
	}

	if response.Status != "success" {
		t.Errorf("期望状态为 'success', 实际为 '%s'", response.Status)
	}
}

// TestCreateUserHandler 测试创建用户处理器
func TestCreateUserHandler(t *testing.T) {
	user := models.User{
		Name:  "测试用户",
		Email: "test@example.com",
		Age:   25,
	}

	jsonData, err := json.Marshal(user)
	if err != nil {
		t.Fatal(err)
	}

	req, err := http.NewRequest("POST", "/api/users", bytes.NewBuffer(jsonData))
	if err != nil {
		t.Fatal(err)
	}
	req.Header.Set("Content-Type", "application/json")

	rr := httptest.NewRecorder()
	handler := http.HandlerFunc(server.CreateUserHandler)

	handler.ServeHTTP(rr, req)

	// 检查状态码
	if status := rr.Code; status != http.StatusCreated {
		t.Errorf("处理器返回错误状态码: got %v want %v", status, http.StatusCreated)
	}

	// 检查响应体
	var response server.Response
	if err := json.Unmarshal(rr.Body.Bytes(), &response); err != nil {
		t.Errorf("无法解析响应JSON: %v", err)
	}

	if response.Status != "success" {
		t.Errorf("期望状态为 'success', 实际为 '%s'", response.Status)
	}
}

// TestCreateUserHandlerInvalidData 测试创建用户处理器（无效数据）
func TestCreateUserHandlerInvalidData(t *testing.T) {
	// 测试空用户名
	user := models.User{
		Name:  "",
		Email: "test@example.com",
		Age:   25,
	}

	jsonData, err := json.Marshal(user)
	if err != nil {
		t.Fatal(err)
	}

	req, err := http.NewRequest("POST", "/api/users", bytes.NewBuffer(jsonData))
	if err != nil {
		t.Fatal(err)
	}
	req.Header.Set("Content-Type", "application/json")

	rr := httptest.NewRecorder()
	handler := http.HandlerFunc(server.CreateUserHandler)

	handler.ServeHTTP(rr, req)

	// 检查状态码
	if status := rr.Code; status != http.StatusBadRequest {
		t.Errorf("处理器返回错误状态码: got %v want %v", status, http.StatusBadRequest)
	}

	// 检查响应体
	var response server.Response
	if err := json.Unmarshal(rr.Body.Bytes(), &response); err != nil {
		t.Errorf("无法解析响应JSON: %v", err)
	}

	if response.Status != "error" {
		t.Errorf("期望状态为 'error', 实际为 '%s'", response.Status)
	}
}

// TestCreateUserHandlerInvalidJSON 测试创建用户处理器（无效JSON）
func TestCreateUserHandlerInvalidJSON(t *testing.T) {
	invalidJSON := []byte(`{"name": "测试用户", "email": "test@example.com", "age":}`)

	req, err := http.NewRequest("POST", "/api/users", bytes.NewBuffer(invalidJSON))
	if err != nil {
		t.Fatal(err)
	}
	req.Header.Set("Content-Type", "application/json")

	rr := httptest.NewRecorder()
	handler := http.HandlerFunc(server.CreateUserHandler)

	handler.ServeHTTP(rr, req)

	// 检查状态码
	if status := rr.Code; status != http.StatusBadRequest {
		t.Errorf("处理器返回错误状态码: got %v want %v", status, http.StatusBadRequest)
	}
}

// TestStatsHandler 测试统计信息处理器
func TestStatsHandler(t *testing.T) {
	req, err := http.NewRequest("GET", "/api/stats", nil)
	if err != nil {
		t.Fatal(err)
	}

	rr := httptest.NewRecorder()
	handler := http.HandlerFunc(server.StatsHandler)

	handler.ServeHTTP(rr, req)

	// 检查状态码
	if status := rr.Code; status != http.StatusOK {
		t.Errorf("处理器返回错误状态码: got %v want %v", status, http.StatusOK)
	}

	// 检查响应体
	var response server.StatsResponse
	if err := json.Unmarshal(rr.Body.Bytes(), &response); err != nil {
		t.Errorf("无法解析响应JSON: %v", err)
	}

	if response.Status != "success" {
		t.Errorf("期望状态为 'success', 实际为 '%s'", response.Status)
	}

	if response.NumCPU <= 0 {
		t.Error("CPU数量应该大于0")
	}

	if response.NumGoroutine <= 0 {
		t.Error("Goroutine数量应该大于0")
	}
}

// TestAPIDocHandler 测试API文档处理器
func TestAPIDocHandler(t *testing.T) {
	req, err := http.NewRequest("GET", "/api", nil)
	if err != nil {
		t.Fatal(err)
	}

	rr := httptest.NewRecorder()
	handler := http.HandlerFunc(server.APIDocHandler)

	handler.ServeHTTP(rr, req)

	// 检查状态码
	if status := rr.Code; status != http.StatusOK {
		t.Errorf("处理器返回错误状态码: got %v want %v", status, http.StatusOK)
	}

	// 检查响应内容类型
	expected := "application/json"
	if ct := rr.Header().Get("Content-Type"); ct != expected {
		t.Errorf("处理器返回错误内容类型: got %v want %v", ct, expected)
	}

	// 检查响应体包含API文档信息
	var doc map[string]interface{}
	if err := json.Unmarshal(rr.Body.Bytes(), &doc); err != nil {
		t.Errorf("无法解析响应JSON: %v", err)
	}

	if _, exists := doc["title"]; !exists {
		t.Error("API文档应该包含title字段")
	}

	if _, exists := doc["endpoints"]; !exists {
		t.Error("API文档应该包含endpoints字段")
	}
}

// TestServer 测试完整的服务器
func TestServer(t *testing.T) {
	// 创建服务器
	srv := server.NewServer(":0") // 使用随机端口
	srv.SetupRoutes()

	// 创建测试服务器
	testServer := httptest.NewServer(srv.GetRouter())
	defer testServer.Close()

	// 测试健康检查
	resp, err := http.Get(testServer.URL + "/health")
	if err != nil {
		t.Fatalf("健康检查请求失败: %v", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		t.Errorf("健康检查返回错误状态码: got %v want %v", resp.StatusCode, http.StatusOK)
	}

	// 测试获取用户列表
	resp, err = http.Get(testServer.URL + "/api/users")
	if err != nil {
		t.Fatalf("获取用户列表请求失败: %v", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		t.Errorf("获取用户列表返回错误状态码: got %v want %v", resp.StatusCode, http.StatusOK)
	}
}

// TestMiddleware 测试中间件
func TestMiddleware(t *testing.T) {
	// 测试CORS中间件
	req, err := http.NewRequest("OPTIONS", "/api/users", nil)
	if err != nil {
		t.Fatal(err)
	}

	rr := httptest.NewRecorder()

	// 创建带中间件的处理器
	handler := server.CORSMiddleware(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	}))

	handler.ServeHTTP(rr, req)

	// 检查CORS头
	if origin := rr.Header().Get("Access-Control-Allow-Origin"); origin != "*" {
		t.Errorf("期望CORS Origin为 '*', 实际为 '%s'", origin)
	}

	if methods := rr.Header().Get("Access-Control-Allow-Methods"); methods == "" {
		t.Error("应该设置Access-Control-Allow-Methods头")
	}
}

// BenchmarkHealthHandler 健康检查处理器基准测试
func BenchmarkHealthHandler(b *testing.B) {
	req, _ := http.NewRequest("GET", "/health", nil)

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		rr := httptest.NewRecorder()
		handler := http.HandlerFunc(server.HealthHandler)
		handler.ServeHTTP(rr, req)
	}
}

// BenchmarkGetUsersHandler 获取用户列表处理器基准测试
func BenchmarkGetUsersHandler(b *testing.B) {
	req, _ := http.NewRequest("GET", "/api/users", nil)

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		rr := httptest.NewRecorder()
		handler := http.HandlerFunc(server.GetUsersHandler)
		handler.ServeHTTP(rr, req)
	}
}

// ExampleHealthHandler 健康检查处理器示例
func ExampleHealthHandler() {
	req, _ := http.NewRequest("GET", "/health", nil)
	rr := httptest.NewRecorder()
	handler := http.HandlerFunc(server.HealthHandler)

	handler.ServeHTTP(rr, req)

	fmt.Printf("Status: %d", rr.Code)
	// Output: Status: 200
}