package api

import (
	"io/ioutil"
	"net/http"
	"os"
	"path"
	"reflect"
	"regexp"
	"strings"
	"time"

	"github.com/juju/errors"
	"github.com/rs/zerolog"

	"git.pyer.club/kingecg/goonvif/onvif"
	"git.pyer.club/kingecg/goonvif/onvif/gosoap"
	"git.pyer.club/kingecg/goonvif/onvif/networking"
	wsdiscovery "git.pyer.club/kingecg/goonvif/onvif/ws-discovery"
	"github.com/beevik/etree"
	"github.com/gin-gonic/gin"
)

var (
	// LoggerContext is the builder of a zerolog.Logger that is exposed to the application so that
	// options at the CLI might alter the formatting and the output of the logs.
	LoggerContext = zerolog.
			New(zerolog.ConsoleWriter{Out: os.Stderr, TimeFormat: time.RFC3339}).
			With().Timestamp()

	// Logger is a zerolog logger, that can be safely used from any part of the application.
	// It gathers the format and the output.
	Logger = LoggerContext.Logger()
)

func RunApi() {
	router := gin.Default()

	router.POST("/:service/:method", func(c *gin.Context) {
		c.Header("Access-Control-Allow-Origin", "*")
		//c.Header("Access-Control-Allow-Headers", "access-control-allow-origin, access-control-allow-headers")

		serviceName := c.Param("service")
		methodName := c.Param("method")
		username := c.GetHeader("username")
		pass := c.GetHeader("password")
		xaddr := c.GetHeader("xaddr")
		acceptedData, err := c.GetRawData()
		if err != nil {
			Logger.Debug().Err(err).Msg("Failed to get rawx data")
		}

		message, err := callNecessaryMethod(serviceName, methodName, string(acceptedData), username, pass, xaddr)
		if err != nil {
			c.XML(http.StatusBadRequest, err.Error())
		} else {
			c.String(http.StatusOK, message)
		}
	})

	router.GET("/discovery", func(context *gin.Context) {
		context.Header("Access-Control-Allow-Origin", "*")
		context.Header("Access-Control-Allow-Headers", "access-control-allow-origin, access-control-allow-headers")

		interfaceName := context.GetHeader("interface")

		devices, err := wsdiscovery.SendProbe(interfaceName, nil, []string{"dn:NetworkVideoTransmitter"}, map[string]string{"dn": "http://www.onvif.org/ver10/network/wsdl"})
		if err != nil {
			context.String(http.StatusInternalServerError, "error")
		} else {
			response := "["

			for _, j := range devices {
				doc := etree.NewDocument()
				if err := doc.ReadFromString(j); err != nil {
					context.XML(http.StatusBadRequest, err.Error())
				} else {

					endpoints := doc.Root().FindElements("./Body/ProbeMatches/ProbeMatch/XAddrs")
					scopes := doc.Root().FindElements("./Body/ProbeMatches/ProbeMatch/Scopes")

					flag := false

					for _, xaddr := range endpoints {
						xaddr := strings.Split(strings.Split(xaddr.Text(), " ")[0], "/")[2]
						if strings.Contains(response, xaddr) {
							flag = true
							break
						}
						response += "{"
						response += `"url":"` + xaddr + `",`
					}
					if flag {
						break
					}
					for _, scope := range scopes {
						re := regexp.MustCompile(`onvif:\/\/www\.onvif\.org\/name\/[A-Za-z0-9-]+`)
						match := re.FindStringSubmatch(scope.Text())
						response += `"name":"` + path.Base(match[0]) + `"`
					}
					response += "},"
				}
			}
			response = strings.TrimRight(response, ",")
			response += "]"
			context.String(http.StatusOK, response)
		}
	})

	router.Run()
}

func callNecessaryMethod(serviceName, methodName, acceptedData, username, password, xaddr string) (string, error) {
	var methodStruct interface{}
	var err error

	switch strings.ToLower(serviceName) {
	case "device":
		methodStruct, err = getDeviceStructByName(methodName)
	case "ptz":
		methodStruct, err = getPTZStructByName(methodName)
	case "media":
		methodStruct, err = getMediaStructByName(methodName)
	default:
		return "", errors.New("there is no such service")
	}
	if err != nil { //done
		return "", errors.Annotate(err, "getStructByName")
	}

	resp, err := xmlAnalize(methodStruct, &acceptedData)
	if err != nil {
		return "", errors.Annotate(err, "xmlAnalize")
	}

	endpoint, err := getEndpoint(serviceName, xaddr)
	if err != nil {
		return "", errors.Annotate(err, "getEndpoint")
	}

	soap := gosoap.NewEmptySOAP()
	soap.AddStringBodyContent(*resp)
	soap.AddRootNamespaces(onvif.Xlmns)
	soap.AddWSSecurity(username, password)

	servResp, err := networking.SendSoap(new(http.Client), endpoint, soap.String())
	if err != nil {
		return "", errors.Annotate(err, "SendSoap")
	}

	rsp, err := ioutil.ReadAll(servResp.Body)
	if err != nil {
		return "", errors.Annotate(err, "ReadAll")
	}

	servResp.Body.Close()

	return string(rsp), nil
}

func getEndpoint(service, xaddr string) (string, error) {
	dev, err := onvif.NewDevice(onvif.DeviceParams{Xaddr: xaddr})
	if err != nil {
		return "", errors.Annotate(err, "NewDevice")
	}
	pkg := strings.ToLower(service)

	var endpoint string
	switch pkg {
	case "device":
		endpoint = dev.GetEndpoint("Device")
	case "event":
		endpoint = dev.GetEndpoint("Event")
	case "imaging":
		endpoint = dev.GetEndpoint("Imaging")
	case "media":
		endpoint = dev.GetEndpoint("Media")
	case "ptz":
		endpoint = dev.GetEndpoint("PTZ")
	}
	return endpoint, nil
}

func xmlAnalize(methodStruct interface{}, acceptedData *string) (*string, error) {
	test := make([]map[string]string, 0)      //tags
	testunMarshal := make([][]interface{}, 0) //data
	var mas []string                          //idnt

	soapHandling(methodStruct, &test)
	test = mapProcessing(test)

	doc := etree.NewDocument()
	if err := doc.ReadFromString(*acceptedData); err != nil {
		return nil, errors.Annotate(err, "readFromString")
	}
	etr := doc.FindElements("./*")
	xmlUnmarshal(etr, &testunMarshal, &mas)
	ident(&mas)

	document := etree.NewDocument()
	var el *etree.Element
	var idntIndex = 0

	for lstIndex := 0; lstIndex < len(testunMarshal); {
		lst := (testunMarshal)[lstIndex]
		elemName, attr, value, err := xmlMaker(&lst, &test, lstIndex)
		if err != nil {
			return nil, errors.Annotate(err, "xmlMarker")
		}

		if mas[lstIndex] == "Push" && lstIndex == 0 { //done
			el = document.CreateElement(elemName)
			el.SetText(value)
			if len(attr) != 0 {
				for key, value := range attr {
					el.CreateAttr(key, value)
				}
			}
		} else if mas[idntIndex] == "Push" {
			pushTmp := etree.NewElement(elemName)
			pushTmp.SetText(value)
			if len(attr) != 0 {
				for key, value := range attr {
					pushTmp.CreateAttr(key, value)
				}
			}
			el.AddChild(pushTmp)
			el = pushTmp
		} else if mas[idntIndex] == "PushPop" {
			popTmp := etree.NewElement(elemName)
			popTmp.SetText(value)
			if len(attr) != 0 {
				for key, value := range attr {
					popTmp.CreateAttr(key, value)
				}
			}
			if el == nil {
				document.AddChild(popTmp)
			} else {
				el.AddChild(popTmp)
			}
		} else if mas[idntIndex] == "Pop" {
			el = el.Parent()
			lstIndex -= 1
		}
		idntIndex += 1
		lstIndex += 1
	}

	resp, err := document.WriteToString()
	if err != nil {
		return nil, errors.Annotate(err, "writeToString")
	}

	return &resp, nil
}

func xmlMaker(lst *[]interface{}, tags *[]map[string]string, lstIndex int) (string, map[string]string, string, error) {
	var elemName, value string
	attr := make(map[string]string)
	for tgIndx, tg := range *tags {
		if tgIndx == lstIndex {
			for index, elem := range *lst {
				if reflect.TypeOf(elem).String() == "[]etree.Attr" {
					conversion := elem.([]etree.Attr)
					for _, i := range conversion {
						attr[i.Key] = i.Value
					}
				} else {
					conversion := elem.(string)
					if index == 0 && lstIndex == 0 {
						res, err := xmlProcessing(tg["XMLName"])
						if err != nil {
							return "", nil, "", errors.Annotate(err, "xmlProcessing")
						}
						elemName = res
					} else if index == 0 {
						res, err := xmlProcessing(tg[conversion])
						if err != nil {
							return "", nil, "", errors.Annotate(err, "xmlProcessing")
						}
						elemName = res
					} else {
						value = conversion
					}
				}
			}
		}
	}
	return elemName, attr, value, nil
}

func xmlProcessing(tg string) (string, error) {
	r, _ := regexp.Compile(`"(.*?)"`)
	str := r.FindStringSubmatch(tg)
	if len(str) == 0 {
		return "", errors.New("out of range")
	}
	attr := strings.Index(str[1], ",attr")
	omit := strings.Index(str[1], ",omitempty")
	attrOmit := strings.Index(str[1], ",attr,omitempty")
	omitAttr := strings.Index(str[1], ",omitempty,attr")

	if attr > -1 && attrOmit == -1 && omitAttr == -1 {
		return str[1][0:attr], nil
	} else if omit > -1 && attrOmit == -1 && omitAttr == -1 {
		return str[1][0:omit], nil
	} else if attr == -1 && omit == -1 {
		return str[1], nil
	} else if attrOmit > -1 {
		return str[1][0:attrOmit], nil
	} else {
		return str[1][0:omitAttr], nil
	}
}

func mapProcessing(mapVar []map[string]string) []map[string]string {
	for indx := 0; indx < len(mapVar); indx++ {
		element := mapVar[indx]
		for _, value := range element {
			if value == "" {
				mapVar = append(mapVar[:indx], mapVar[indx+1:]...)
				indx--
			}
			if strings.Index(value, ",attr") != -1 {
				mapVar = append(mapVar[:indx], mapVar[indx+1:]...)
				indx--
			}
		}
	}
	return mapVar
}

func soapHandling(tp interface{}, tags *[]map[string]string) {
	s := reflect.ValueOf(tp).Elem()
	typeOfT := s.Type()
	if s.Kind() != reflect.Struct {
		return
	}
	for i := 0; i < s.NumField(); i++ {
		f := s.Field(i)
		tmp, ok := typeOfT.FieldByName(typeOfT.Field(i).Name)
		if !ok {
			Logger.Debug().Str("field", typeOfT.Field(i).Name).Msg("reflection failed")
		}
		*tags = append(*tags, map[string]string{typeOfT.Field(i).Name: string(tmp.Tag)})
		subStruct := reflect.New(reflect.TypeOf(f.Interface()))
		soapHandling(subStruct.Interface(), tags)
	}
}

func xmlUnmarshal(elems []*etree.Element, data *[][]interface{}, mas *[]string) {
	for _, elem := range elems {
		*data = append(*data, []interface{}{elem.Tag, elem.Attr, elem.Text()})
		*mas = append(*mas, "Push")
		xmlUnmarshal(elem.FindElements("./*"), data, mas)
		*mas = append(*mas, "Pop")
	}
}

func ident(mas *[]string) {
	var buffer string
	for _, j := range *mas {
		buffer += j + " "
	}
	buffer = strings.Replace(buffer, "Push Pop ", "PushPop ", -1)
	buffer = strings.TrimSpace(buffer)
	*mas = strings.Split(buffer, " ")
}