package toolhttp

import (
	"bytes"
	"gitee.com/liujinsuo/tool"
	"github.com/pkg/errors"
	"io"
	"net"
	"net/http"
	"reflect"
	"strings"
)

type httpT struct {
}

// GetResponseStatus 获取响应状态与响应body
func (s *httpT) GetResponseStatus(w http.ResponseWriter) (status int, body []byte, err error) {
	defer func() {
		if r := recover(); r != nil {
			err = errors.Errorf("panic %+v", r)
		}
	}()
	v := reflect.ValueOf(w).Elem()
	status = int(v.FieldByName("status").Int()) //状态
	responseW := v.FieldByName("w")
	if responseW.IsNil() == true {
		return //没有响应body
	} else {
		n := responseW.Elem().FieldByName("n").Int()
		body = responseW.Elem().FieldByName("buf").Bytes()[:n] //body
	}
	return
}

// GetRequestParam 获取请求参数
func (s *httpT) GetRequestParam(r *http.Request) ([]byte, error) {
	ContentType := r.Header.Get("Content-Type")
	if strings.Contains(ContentType, "multipart/form-data") == true {
		return nil, nil
	}

	if r.Method == http.MethodGet ||
		r.Method == http.MethodOptions ||
		r.Method == http.MethodHead ||
		r.Method == http.MethodDelete {
		return nil, nil
	}

	//读取body
	p, err := io.ReadAll(r.Body)
	if err != nil {
		return nil, errors.Wrap(err, "读取body失败")
	}

	//写回去
	r.Body = io.NopCloser(bytes.NewReader(p))
	if ContentType == "application/json" {
		if len(p) <= 0 {
			return nil, nil
		}
		//压缩json
		if r, err := tool.JsonCompression(p); err != nil {
			return nil, errors.Wrap(err, "压缩json失败")
		} else {
			return r, nil
		}
	} else if ContentType == "application/x-www-form-urlencoded" {
		return p, nil
	} else {
		return p, nil
	}
}

// ClientIP 尽最大努力实现获取客户端 IP 的算法。
// 解析 X-Real-IP 和 X-Forwarded-For 以便于反向代理（nginx 或 haproxy）可以正常工作。
func (s *httpT) ClientIP(r *http.Request) string {
	xForwardedFor := r.Header.Get("X-Forwarded-For")
	ip := strings.TrimSpace(strings.Split(xForwardedFor, ",")[0])
	if ip != "" {
		return ip
	}

	ip = strings.TrimSpace(r.Header.Get("X-Real-Ip"))
	if ip != "" {
		return ip
	}

	if ip, _, err := net.SplitHostPort(strings.TrimSpace(r.RemoteAddr)); err == nil {
		return ip
	}

	return ""
}

// RemoteIP parses the IP from Request.RemoteAddr, normalizes and returns the IP (without the port).
func (s *httpT) RemoteIP(r *http.Request) string {
	ip, _, err := net.SplitHostPort(strings.TrimSpace(r.RemoteAddr))
	if err != nil {
		return ""
	}
	return ip
}

var HTTP = new(httpT)