vindn.de/backend/utils/ApiClient.go

package utils

import (
	"encoding/json"
	"fmt"
	"log"
	"net/http"
	"os"
	"regexp"
	"strconv"
	"strings"
	"time"
	"whimsoc/vindn-backend/models"
)

// odhText mirrors one entry of an ODH item's "texts" array (rel/type/value
// triples holding description, teaser, price info, etc. in several
// languages/formats).
type odhText struct {
	Rel   string `json:"rel"`
	Type  string `json:"type"`
	Value string `json:"value"`
}

// odhExtras captures the ODH fields that don't map onto flat Event columns
// by name (description/teaser live inside "texts", dates inside
// "timeIntervals") and need extraction after the plain json.Unmarshal.
type odhExtras struct {
	Texts         []odhText `json:"texts"`
	TimeIntervals []struct {
		Start string `json:"start"`
		End   string `json:"end"`
	} `json:"timeIntervals"`
}

var htmlTagPattern = regexp.MustCompile(`<[^>]*>`)

// extractText returns the plain-text value of the first "texts" entry whose
// rel matches one of the given candidates (checked in order), preferring a
// text/plain variant over text/html and stripping tags if only html exists.
func extractText(texts []odhText, rels ...string) string {
	var htmlFallback string
	for _, rel := range rels {
		for _, t := range texts {
			if t.Rel != rel || t.Value == "" {
				continue
			}
			if t.Type == "text/plain" {
				return t.Value
			}
			if htmlFallback == "" && t.Type == "text/html" {
				htmlFallback = t.Value
			}
		}
	}
	return strings.TrimSpace(htmlTagPattern.ReplaceAllString(htmlFallback, ""))
}

func FetchDataFromAPI2(url string) ([]models.Event, error) {
	resp, err := http.Get(url)
	if err != nil {
		log.Printf("Failed to fetch data: %v", err)
		return nil, err
	}
	defer resp.Body.Close()

	var events []models.Event
	if err := json.NewDecoder(resp.Body).Decode(&events); err != nil {
		log.Printf("Failed to decode JSON: %v", err)
		return nil, err
	}

	return events, nil
}

func FetchDataFromAPI() ([]models.Event, error) {
	fmt.Println("Starting to get odh files")

	//dataHubTypes := [5]string{"Tour", "POI", "Gastro", "Hotel", "Event"}
	dataHubTypes := [1]string{"Event"}
	licenseKey := os.Getenv("ODH_LICENCE_KEY")

	var events []models.Event

	for _, dataHubType := range dataHubTypes {
		queryOffset := 0
		limit := 20

		for {
			rawItems, err := getItemsRaw(dataHubType, licenseKey, queryOffset, limit)
			if err != nil {
				log.Fatalf("Failed to fetch items: %v", err)
			}

			if len(rawItems) == 0 {
				break
			}

			for _, rawItem := range rawItems {
				var event models.Event

				if err := json.Unmarshal(rawItem, &event); err != nil {
					log.Printf("Failed to decode JSON: %v", err)
					return nil, err
				}

				var extras odhExtras
				if err := json.Unmarshal(rawItem, &extras); err != nil {
					log.Printf("Failed to decode text/date extras for %s: %v", event.ExternalID, err)
				} else {
					event.Description = extractText(extras.Texts, "details", "open-data-nrw-detail")
					event.Teaser = extractText(extras.Texts, "teaser", "open-data-nrw-teaser")
					if len(extras.TimeIntervals) > 0 {
						event.StartDate = extras.TimeIntervals[0].Start
						event.EndDate = extras.TimeIntervals[0].End
					}
				}

				fmt.Printf("Successfully got event %s \"%s\"\n", event.ExternalID, event.Title)

				events = append(events, event)
			}

			queryOffset += limit

		}

	}

	return events, nil

}

// get all items of a single type
func getItemsRaw(dataHubType string, licenseKey string, queryOffset int, limit int) ([]json.RawMessage, error) {
	req, err := http.NewRequest("GET", "https://meta.et4.de/rest.ashx/search/", nil)
	if err != nil {
		log.Print(err)
		os.Exit(1)
	}

	q := req.URL.Query()
	q.Add("experience", "open-data-nrw-tourismus")
	q.Add("type", dataHubType)
	q.Add("licenseKey", licenseKey)
	q.Add("q", "area:\"Nordrhein-Westfalen\"")
	q.Add("template", "ET2014A.json")
	q.Add("limit", strconv.Itoa(limit))
	q.Add("offset", strconv.Itoa(queryOffset))
	q.Add("sort", "id asc")
	req.URL.RawQuery = q.Encode()

	fmt.Println("Query: " + req.URL.String())

	client := http.Client{
		Timeout: 30 * time.Second,
	}

	resp, err := client.Do(req)
	if err != nil {
		fmt.Printf("client: error making http request: %s\n", err)
		os.Exit(1)
	}

	defer resp.Body.Close()

	var apiResp models.ApiResponseRaw
	if err := json.NewDecoder(resp.Body).Decode(&apiResp); err != nil {
		return nil, err
	}

	return apiResp.Items, nil
}