NdoleStudio / httpsms

import (

	"bytes"

	"context"

	"fmt"

	"io"

	"mime/multipart"

	"net/url"

	"strings"

	"time"

	"github.com/xuri/excelize/v2"

	"github.com/NdoleStudio/httpsms/pkg/entities"

	"github.com/NdoleStudio/httpsms/pkg/repositories"

	"github.com/NdoleStudio/httpsms/pkg/requests"

	"github.com/NdoleStudio/httpsms/pkg/services"

	"github.com/NdoleStudio/httpsms/pkg/telemetry"

	"github.com/dustin/go-humanize"

	"github.com/jszwec/csvutil"

	"github.com/nyaruka/phonenumbers"

	"github.com/palantir/stacktrace"

)

// BulkMessageHandlerValidator validates models used in handlers.BillingHandler

type BulkMessageHandlerValidator struct {

	validator

	phoneService *services.PhoneService

	userService  *services.UserService

	logger       telemetry.Logger

	tracer       telemetry.Tracer

}

// NewBulkMessageHandlerValidator creates a new handlers.BulkMessageHandlerValidator validator

func NewBulkMessageHandlerValidator(

	logger telemetry.Logger,

	tracer telemetry.Tracer,

	phoneService *services.PhoneService,

	userService *services.UserService,

) (v *BulkMessageHandlerValidator) {

	return &BulkMessageHandlerValidator{

		logger:       logger.WithService(fmt.Sprintf("%T", v)),

		tracer:       tracer,

		userService:  userService,

		phoneService: phoneService,

	}

}

// ValidateStore validates the requests.BillingUsageHistory request

func (v *BulkMessageHandlerValidator) ValidateStore(ctx context.Context, userID entities.UserID, header *multipart.FileHeader) ([]*requests.BulkMessage, url.Values) {

	ctx, span, ctxLogger := v.tracer.StartWithLogger(ctx, v.logger)

	defer span.End()

	user, err := v.userService.GetByID(ctx, userID)

	if err != nil {

		result := url.Values{}

		result.Add("document", "Cannot load your account. Please try again later or contact support.")

		ctxLogger.Error(v.tracer.WrapErrorSpan(span, stacktrace.Propagate(err, fmt.Sprintf("cannot load user [%s]", userID))))

		return nil, result

	}

	messages, result := v.parseFile(ctxLogger, user, header)

	if len(result) != 0 {

		return messages, result

	}

	if len(messages) == 0 {

		result.Add("document", "The uploaded file doesn't contain any valid records. Make sure you are using the official httpSMS template.")

		return messages, result

	}

	if len(messages) > 1000 {

		result.Add("document", "The uploaded file must contain less than 1000 records.")

		return messages, result

	}

	for index, message := range messages {

		messages[index] = message.Sanitize()

	}

	result = v.validateMessages(messages)

	if len(result) != 0 {

		return messages, result

	}

	result = v.validateOwners(ctx, userID, messages)

	if len(result) != 0 {

		return messages, result

	}

	return messages, result

}

func (v *BulkMessageHandlerValidator) parseFile(ctxLogger telemetry.Logger, user *entities.User, header *multipart.FileHeader) ([]*requests.BulkMessage, url.Values) {

	if header.Header.Get("Content-Type") == "text/csv" || strings.HasSuffix(header.Filename, ".csv") {

		return v.parseCSV(ctxLogger, user, header)

	}

	if header.Header.Get("Content-Type") == "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" || strings.HasSuffix(header.Filename, ".xlsx") {

		return v.parseXlsx(ctxLogger, user, header)

	}

	ctxLogger.Error(stacktrace.NewError(fmt.Sprintf("cannot parse file [%s] for user [%s] with content type [%s]", header.Filename, user.ID, header.Header.Get("Content-Type"))))

	result := url.Values{}

	result.Add("document", fmt.Sprintf("The file [%s] is not a valid CSV or Excel file.", header.Filename))

	return nil, result

}

func (v *BulkMessageHandlerValidator) convertExcelTime(user *entities.User, value string) (*time.Time, error) {

	t, err := time.ParseInLocation("2006-01-02T15:04:05", value, user.Location())

	if err != nil {

		return nil, stacktrace.Propagate(err, fmt.Sprintf("cannot parse excel time [%s] as [%T]", value, t))

	}

	return &t, nil

}

func (v *BulkMessageHandlerValidator) parseBytes(ctxLogger telemetry.Logger, userID entities.UserID, header *multipart.FileHeader) ([]byte, url.Values) {

	result := url.Values{}

	if header.Size >= 5000000 {

		result.Add("document", fmt.Sprintf("The CSV file must be less than 500 KB the file you uploaded is [%s].", humanize.Bytes(uint64(header.Size))))

		return nil, result

	}

	file, err := header.Open()

	if err != nil {

		ctxLogger.Error(stacktrace.Propagate(err, fmt.Sprintf("cannot open file [%s] for reading for user [%s]", header.Filename, userID)))

		result.Add("document", fmt.Sprintf("Cannot open the uploaded file with name [%s].", header.Filename))

		return nil, result

	}

	defer func() {

		if e := file.Close(); e != nil {

			ctxLogger.Error(stacktrace.Propagate(e, fmt.Sprintf("cannot close file [%s] for user [%s]", header.Filename, userID)))

		}

	}()

	b := new(bytes.Buffer)

	if _, err = io.Copy(b, file); err != nil {

		ctxLogger.Error(stacktrace.Propagate(err, fmt.Sprintf("cannot copy file [%s] to buffer for user [%s]", header.Filename, userID)))

		result.Add("document", fmt.Sprintf("Cannot read the conents of the uploaded file [%s].", header.Filename))

		return nil, result

	}

	return b.Bytes(), result

}

func (v *BulkMessageHandlerValidator) parseCSV(ctxLogger telemetry.Logger, user *entities.User, header *multipart.FileHeader) ([]*requests.BulkMessage, url.Values) {

	content, result := v.parseBytes(ctxLogger, user.ID, header)

	if len(result) != 0 {

		return nil, result

	}

	var messages []*requests.BulkMessage

	if err := csvutil.Unmarshal(content, &messages); err != nil {

		ctxLogger.Error(stacktrace.Propagate(err, fmt.Sprintf("cannot unmarshall contents [%s] into type [%T] for file [%s] and user [%s]", content, messages, header.Filename, user.ID)))

		result.Add("document", fmt.Sprintf("Cannot read the conents of the uploaded file [%s].", header.Filename))

		return nil, result

	}

	return messages, url.Values{}

}

func (v *BulkMessageHandlerValidator) validateMessages(messages []*requests.BulkMessage) url.Values {

	result := url.Values{}

	for index, message := range messages {

		if _, err := phonenumbers.Parse(message.FromPhoneNumber, phonenumbers.UNKNOWN_REGION); err != nil {

			result.Add("document", fmt.Sprintf("Row [%d]: The FromPhoneNumber [%s] is not a valid E.164 phone number", index+2, message.FromPhoneNumber))

		}

		if _, err := phonenumbers.Parse(message.ToPhoneNumber, phonenumbers.UNKNOWN_REGION); err != nil {

			result.Add("document", fmt.Sprintf("Row [%d]: The ToPhoneNumber [%s] is not a valid E.164 phone number", index+2, message.ToPhoneNumber))

		}

		if len(message.Content) > 1024 {

			result.Add("document", fmt.Sprintf("Row [%d]: The message content must be less than 1024 characters.", index+2))

		}

		if message.SendTime != nil && message.SendTime.After(time.Now().Add(420*time.Hour)) {

			result.Add("document", fmt.Sprintf("Row [%d]: The SendTime [%s] cannot be more than 20 days (420 hours) in the future.", index+2, message.SendTime.Format(time.RFC3339)))

		}

	}

	return result

}

func (v *BulkMessageHandlerValidator) validateOwners(ctx context.Context, userID entities.UserID, messages []*requests.BulkMessage) url.Values {

	numbers := map[string][]int{}

	for index, message := range messages {

		numbers[message.FromPhoneNumber] = append(numbers[message.FromPhoneNumber], index+2)

	}

	result := url.Values{}

	for number, rows := range numbers {

		_, err := v.phoneService.Load(ctx, userID, strings.TrimSpace(number))

		if stacktrace.GetCode(err) == repositories.ErrCodeNotFound {

			result.Add("document", fmt.Sprintf("Rows [%s]: The FromPhoneNumber [%s] is not registered on your account", v.toString(rows), number))

		}

	}

	return result

}

func (v *BulkMessageHandlerValidator) toString(value []int) string {

	result := strings.Builder{}

	for index, row := range value {

		if index != 0 {

			result.WriteString(", ")

		}

		result.WriteString(fmt.Sprintf("%d", row))

	}

	return result.String()

}