timetable-mgr/src/vstp/parser.go

package vstp

import (
	"encoding/json"
	"fmt"
	"strconv"
	"time"

	"git.fjla.uk/owlboard/go-types/pkg/database"
	"git.fjla.uk/owlboard/go-types/pkg/upstreamApi"
	"git.fjla.uk/owlboard/mq-client/helpers"
	"git.fjla.uk/owlboard/mq-client/log"
)

// Unmarshals the JSON data and runs it through the formatData() function and returns the data in a DB ready Struct
func unmarshalData(jsonData string) database.Service {
	log.Msg.Debug("Unmarshalling message body")
	fmt.Println(jsonData)
	log.Msg.Debug("Converting to byte array")
	jsonDataBytes := []byte(jsonData)
	var schedule upstreamApi.VstpMsg
	err := json.Unmarshal(jsonDataBytes, &schedule)
	if err != nil {
		log.Msg.Error("Unable to unmarshal message body: " + err.Error())
		//return err
	}
	log.Msg.Debug("Unmarshalling Complete")
	fmt.Println(schedule)
	saveToFile(schedule, "unmarshalled")
	return formatData(schedule.CIFMsg)
}

// Transforms the upstreamApi.Schedule type into a database.Service type
func formatData(dataInput *upstreamApi.Schedule) database.Service {
	log.Msg.Debug("ScheduleSegment length: " + fmt.Sprint(len(dataInput.ScheduleSegment)))
	service := database.Service{
		TransactionType:   dataInput.TransactionType,
		StpIndicator:      dataInput.CIFSTPIndicator,
		Operator:          dataInput.ScheduleSegment[0].ATOCCode,
		TrainUid:          dataInput.CIFTrainUID,
		Headcode:          dataInput.ScheduleSegment[0].SignallingID,
		PowerType:         dataInput.ScheduleSegment[0].CIFPowerType,
		PlanSpeed:         parseSpeed(dataInput.ScheduleSegment[0].CIFSpeed),
		ScheduleStartDate: parseDate(dataInput.ScheduleStartDate, false),
		ScheduleEndDate:   parseDate(dataInput.ScheduleEndDate, true),
		DaysRun:           parseDaysRun(dataInput.ScheduleDaysRun),
		Stops:             parseStops(dataInput.ScheduleSegment[0].ScheduleLocation),
	}
	return service
}

// Uses the map provided in 'helpers' to translate incorrect CIF speeds to their correct equivalent
func parseSpeed(CIFSpeed string) int32 {
	log.Msg.Debug("CIFSpeed Input: " + CIFSpeed)
	actualSpeed, exists := helpers.SpeedMap[CIFSpeed]
	if !exists {
		actualSpeed = CIFSpeed
	}
	log.Msg.Debug("Corrected Speed: " + actualSpeed)

	speed, err := strconv.ParseInt(actualSpeed, 10, 32)
	if err != nil {
		log.Msg.Warn("Unable to parse speed: " + CIFSpeed + " " + actualSpeed)
		return 0
	}
	return int32(speed)
}

// Converts the date string provided from the upstream API into a proper Date type and adds a time
func parseDate(dateString string, end bool) time.Time {
	log.Msg.Debug("Date Input: " + dateString)
	date, err := time.Parse("2006-01-02", dateString)
	if err != nil {
		log.Msg.Error("Unable to parse date: " + dateString)
		return time.Time{}
	}
	log.Msg.Debug("Parsed date: " + date.String())

	var hour, minute, second, nanosecond int
	location := time.UTC
	if end {
		hour, minute, second, nanosecond = 23, 59, 59, 999999999
	} else {
		hour, minute, second, nanosecond = 0, 0, 0, 0
	}

	dateWithTime := time.Date(date.Year(), date.Month(), date.Day(), hour, minute, second, nanosecond, location)
	return dateWithTime
}

// Converts the binary stype 'daysRun' field into an array of short days
func parseDaysRun(daysBinary string) []string {
	log.Msg.Debug("daysRun Input: " + daysBinary)
	shortDays := []string{"m", "t", "w", "th", "f", "s", "su"}
	var result []string
	for i, digit := range daysBinary {
		if digit == '1' {
			result = append(result, shortDays[i])
		}
	}
	return result
}

// Converts an array if upstreamApi.ScheduleLocation types to an array of database.Stop types
func parseStops(inputStops []upstreamApi.ScheduleLocation) []database.Stop {
	var stops []database.Stop

	for _, loc := range inputStops {
		stop := database.Stop{
			PublicDeparture: getStringPointer(loc.PublicDepartureTime),
			WttDeparture:    getStringPointer(loc.ScheduledDepartureTime),
			PublicArrival:   getStringPointer(loc.PublicArrivalTime),
			WttArrival:      getStringPointer(loc.ScheduledArrivalTime),
			IsPublic:        loc.PublicDepartureTime != "" || loc.PublicArrivalTime != "",
			Tiploc:          loc.Location.Tiploc.TiplocID,
		}

		stops = append(stops, stop)
	}

	return stops
}

func getStringPointer(s string) *string {
	if s == "" {
		return nil
	}
	return &s
}