package utils

import (
	"bytes"
	"context"
	"encoding/json"
	"fmt"
	"io/ioutil"
	"net/http"
	"time"
)

// HTTPClient HTTP客户端工具
type HTTPClient struct {
	client *http.Client
}

// NewHTTPClient 创建HTTP客户端实例
func NewHTTPClient(timeout int) *HTTPClient {
	return &HTTPClient{
		client: &http.Client{
			Timeout: time.Duration(timeout) * time.Second,
		},
	}
}

// Get 发送GET请求
func (h *HTTPClient) Get(url string, headers map[string]string) ([]byte, error) {
	req, err := http.NewRequest("GET", url, nil)
	if err != nil {
		return nil, err
	}

	// 添加请求头
	for key, value := range headers {
		req.Header.Set(key, value)
	}

	return h.doRequest(req)
}

// Post 发送POST请求
func (h *HTTPClient) Post(url string, data interface{}, headers map[string]string) ([]byte, error) {
	// 序列化数据
	jsonData, err := json.Marshal(data)
	if err != nil {
		return nil, err
	}

	// 创建请求
	req, err := http.NewRequest("POST", url, bytes.NewBuffer(jsonData))
	if err != nil {
		return nil, err
	}

	// 设置Content-Type
	req.Header.Set("Content-Type", "application/json")

	// 添加其他请求头
	for key, value := range headers {
		req.Header.Set(key, value)
	}

	return h.doRequest(req)
}

// Put 发送PUT请求
func (h *HTTPClient) Put(url string, data interface{}, headers map[string]string) ([]byte, error) {
	// 序列化数据
	jsonData, err := json.Marshal(data)
	if err != nil {
		return nil, err
	}

	// 创建请求
	req, err := http.NewRequest("PUT", url, bytes.NewBuffer(jsonData))
	if err != nil {
		return nil, err
	}

	// 设置Content-Type
	req.Header.Set("Content-Type", "application/json")

	// 添加其他请求头
	for key, value := range headers {
		req.Header.Set(key, value)
	}

	return h.doRequest(req)
}

// Delete 发送DELETE请求
func (h *HTTPClient) Delete(url string, headers map[string]string) ([]byte, error) {
	req, err := http.NewRequest("DELETE", url, nil)
	if err != nil {
		return nil, err
	}

	// 添加请求头
	for key, value := range headers {
		req.Header.Set(key, value)
	}

	return h.doRequest(req)
}

// doRequest 执行HTTP请求
func (h *HTTPClient) doRequest(req *http.Request) ([]byte, error) {
	// 创建带超时的上下文
	ctx, cancel := context.WithTimeout(context.Background(), h.client.Timeout)
	defer cancel()
	
	req = req.WithContext(ctx)

	// 发送请求
	resp, err := h.client.Do(req)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()

	// 读取响应
	body, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		return nil, err
	}

	// 检查响应状态码
	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
		return nil, fmt.Errorf("HTTP请求失败，状态码: %d，响应内容: %s", resp.StatusCode, string(body))
	}

	return body, nil
}