package auth

import (
	"bytes"
	"errors"
	"fmt"
	"golib.gaore.com/GaoreGo/gaore-common-sdk-go/sdk/requests"
	"golib.gaore.com/GaoreGo/gaore-common-sdk-go/sdk/utils"
	"net/http"
	"net/url"
	"strconv"
	"strings"
	"time"
)

func signRpcRequest(request requests.AcsRequest, signer Signer) (err error) {
	err = completeRpcSignParams(request, signer)
	if err != nil {
		return
	}
	if _, isContainsSign := request.GetQueryParams()["sign"]; isContainsSign {
		delete(request.GetQueryParams(), "sign")
	}

	stringToSign := buildRpcStringToSign(request)
	request.SetStringToSign(stringToSign)
	signature := signer.Sign(stringToSign, "&")
	request.GetQueryParams()["sign"] = signature
	debug("grsdk sign %s", signature)
	return
}

func completeRpcSignParams(request requests.AcsRequest, signer Signer) (err error) {

	var accessKeyFrom string
	if accessKeyFrom, err = signer.GetAccessKeyFrom(); err != nil {
		return
	}

	queryParams := request.GetQueryParams()
	queryParams["access_time"] = fmt.Sprintf("%d", time.Now().Unix())
	queryParams["access_key"], err = signer.GetAccessKeyId()
	queryParams["access_from"] = accessKeyFrom

	if err != nil {
		return
	}

	request.GetHeaders()["Content-type"] = requests.Form
	request.GetHeaders()["Gr-Sdk-From"] = accessKeyFrom
	formString := utils.GetUrlFormedMap(request.GetFormParams())
	request.SetContent(bytes.NewBufferString(formString).Bytes())
	return
}

func buildRpcStringToSign(request requests.AcsRequest) (stringToSign string) {
	signParams := make(map[string]string)
	for key, value := range request.GetQueryParams() {
		signParams[key] = value
	}

	if strings.ToUpper(request.GetMethod()) == requests.POST {
		for key, value := range request.GetFormParams() {
			signParams[key] = value
		}
	}

	stringToSign = utils.GetUrlFormedMap(signParams)
	stringToSign = strings.Replace(stringToSign, "+", "%20", -1)
	stringToSign = strings.Replace(stringToSign, "*", "%2A", -1)
	stringToSign = strings.Replace(stringToSign, "%7E", "~", -1)
	stringToSign = url.QueryEscape(stringToSign)
	stringToSign = request.GetMethod() + "&%2F&" + stringToSign
	return
}

func unsignRpcRequest(request *http.Request, signer Signer) (err error) {
	signParams := make(map[string]string)
	for key, value := range request.URL.Query() {
		signParams[key] = value[0]
	}

	if strings.ToUpper(request.Method) == requests.POST {
		for key, value := range request.Form {
			signParams[key] = value[0]
		}
	}

	if accessKey, err := signer.GetAccessKeyId(); err != nil {
		return err
	} else if accessKey == "" {
		return errors.New("access key is not allow empty")
	} else if accessKey != signParams["access_key"] {
		return errors.New("illegal access key")
	}

	signValue, ok := signParams["sign"]
	if !ok {
		return errors.New("sign value is not exists")
	} else {
		delete(signParams, "sign")
	}

	stringToSign := utils.GetUrlFormedMap(signParams)
	stringToSign = strings.Replace(stringToSign, "+", "%20", -1)
	stringToSign = strings.Replace(stringToSign, "*", "%2A", -1)
	stringToSign = strings.Replace(stringToSign, "%7E", "~", -1)
	stringToSign = url.QueryEscape(stringToSign)
	stringToSign = request.Method + "&%2F&" + stringToSign
	debug("grsdk signstring %s", stringToSign)

	if timestamp, err := strconv.ParseInt(signParams["access_time"], 10, 64); err != nil {
		return err
	} else {
		if time.Unix(timestamp, 0).Before(time.Now().Add(-5 * time.Minute)) {
			err = errors.New("sign timeout 5 minute")
		}
	}

	if signer.Sign(stringToSign, "&") != signValue {
		return errors.New("sign string is  not correct")
	}
	return
}