package util

import (
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"net/http"
	netUrl "net/url"
	"strings"
	"time"

	"github.com/zeromicro/go-zero/core/logx"
)

const (
	TimeOut = time.Duration(30) * time.Second // http请求超时时间, 默认30s
)

type HttpUtil struct {
	log       logx.Logger
	ReqConfig *ReqConfig    // 请求参数
	TimeOut   time.Duration // 超时时间
	Request   *http.Request // 请求request
	Response  *Response     // 响应结果
	Error     error
}

// ReqConfig 请求参数
type ReqConfig struct {
	Headers   map[string]string
	QueryArgs map[string]any
	BodyArgs  map[string]any
}

type Response struct {
	Status     string // e.g. "200 OK"
	StatusCode int    // e.g. 200
	Header     http.Header
	Body       []byte // body实体，即io.ReadAll(resp.body)后的结果
}

func NewHttpUtil(log logx.Logger) *HttpUtil {
	return &HttpUtil{
		log: log,
	}
}

// Get GET请求
// @param url 请求的http地址
// @param reqConfig 中header、query、body等参数
func (h *HttpUtil) Get(url string, reqConfig *ReqConfig) *HttpUtil {
	return h.NewRequest(http.MethodGet, url, reqConfig)
}

// Post POST请求
func (h *HttpUtil) Post(url string, reqConfig *ReqConfig) *HttpUtil {
	return h.NewRequest(http.MethodPost, url, reqConfig)
}

// Put PUT请求
func (h *HttpUtil) Put(url string, reqConfig *ReqConfig) *HttpUtil {
	return h.NewRequest(http.MethodPut, url, reqConfig)
}

// Delete DELETE请求
func (h *HttpUtil) Delete(url string, reqConfig *ReqConfig) *HttpUtil {
	return h.NewRequest(http.MethodDelete, url, reqConfig)
}

// NewRequest 组装请求参数
func (h *HttpUtil) NewRequest(method, url string, reqConfig *ReqConfig) (hc *HttpUtil) {
	if h.Error != nil {
		return h
	}
	h.ReqConfig = reqConfig
	hc = h
	// 请求
	req, err := http.NewRequest(method, url, nil)
	if err != nil {
		h.log.WithFields([]logx.LogField{{Key: "method", Value: method}, {Key: "url", Value: url}, {Key: "reqConfig", Value: reqConfig}}...).
			Errorf("[HttpUtil][NewRequest] http new request error", err)
		hc.Error = err
		return
	}
	hc.Request = req
	// 请求参数
	err = hc.requestConfig()
	if err != nil {
		hc.Error = err
		return
	}
	return
}

// Do http请求及响应处理
func (h *HttpUtil) Do() (hc *HttpUtil) {
	if h.Error != nil {
		return h
	}
	hc = h
	// http请求
	timeOut := hc.TimeOut
	if hc.TimeOut == 0 {
		timeOut = TimeOut
	}
	client := &http.Client{}
	client.Timeout = timeOut
	// 开始请求
	resp, err := client.Do(hc.Request)
	if err != nil {
		h.log.WithFields(logx.LogField{Key: "req", Value: hc.Request}).
			Errorf("[HttpUtil][Do] http client do error", err)
		hc.Error = err
		return
	}
	defer resp.Body.Close()

	content, err := io.ReadAll(resp.Body)
	if err != nil {
		h.log.WithFields(logx.LogField{Key: "req", Value: hc.Request}).
			Errorf("[HttpUtil][Do] http response ReadAll error", err)
		hc.Error = err
		return
	}
	fmt.Printf("===== http response content: %s\n", content)
	hc.Response = &Response{
		Status:     resp.Status,
		StatusCode: resp.StatusCode,
		Header:     resp.Header,
		Body:       content,
	}

	return
}

// Result 获取http的响应结果
// @param result 为结构体（指针类型），解析http请求返回数据json.Unmarshal后的结构
func (h *HttpUtil) Result(result any) (hc *HttpUtil) {
	if h.Error != nil {
		return h
	}
	hc = h
	if result == nil {
		return
	}
	if hc.Response == nil || len(hc.Response.Body) == 0 {
		return
	}

	err := json.Unmarshal(hc.Response.Body, &result)
	if err != nil {
		h.log.WithFields(logx.LogField{Key: "HttpUtil", Value: hc}, logx.LogField{Key: "result", Value: result}).
			Errorf("[HttpUtil][Result] http response body json unmarshal error", err)
		hc.Error = err
		return
	}
	return
}

// 请求参数
func (h *HttpUtil) requestConfig() error {
	if h.Request == nil {
		return errors.New("http request is nil")
	}
	if h.ReqConfig == nil {
		return nil
	}
	// header参数
	if h.ReqConfig.Headers != nil {
		for key, value := range h.ReqConfig.Headers {
			h.Request.Header.Set(key, value)
		}
	}

	// 请求query参数
	queryParams := h.Request.URL.Query()
	if h.ReqConfig.QueryArgs != nil {
		for key, value := range h.ReqConfig.QueryArgs {
			queryParams.Add(key, fmt.Sprint(value))
		}
	}
	h.Request.URL.RawQuery = queryParams.Encode()
	// 请求body参数
	if h.ReqConfig.BodyArgs != nil {
		switch h.Request.Header.Get("Content-Type") {
		case "application/x-www-form-urlencoded":
			form := make(netUrl.Values)
			for k, v := range h.ReqConfig.BodyArgs {
				form.Add(k, fmt.Sprint(v))
			}
			h.Request.Body = io.NopCloser(strings.NewReader(form.Encode()))
		case "application/json":
			data, err := json.Marshal(h.ReqConfig.BodyArgs)
			if err != nil {
				h.Error = err
				return err
			}
			h.Request.Body = io.NopCloser(strings.NewReader(string(data)))
		}
	}
	return nil
}