1 files changed, 146 insertions, 0 deletions
diff --git a/pkg/schedule/service.go b/pkg/schedule/service.go
new file mode 100644
index 0000000..70587ef
--- /dev/null
+++ b/pkg/schedule/service.go
@@ -0,0 +1,146 @@
+package schedule
+
+import (
+	"bufio"
+	"encoding/xml"
+	"fmt"
+	"net/http"
+	"sync"
+	"time"
+)
+
+type Service interface {
+	GetSchedule() (*Schedule, *time.Time, error)
+}
+
+type Schedule struct {
+	XMLName    xml.Name   `json:"-" xml:"schedule"`
+	Conference Conference `json:"conference" xml:"conference"`
+	Tracks     []Track    `json:"tracks" xml:"tracks>track"`
+	Days       []Day      `json:"days" xml:"day"`
+}
+
+type Conference struct {
+	Title            string `json:"title" xml:"title"`
+	Venue            string `json:"venue" xml:"venue"`
+	City             string `json:"city" xml:"city"`
+	Start            string `json:"start" xml:"start"`
+	End              string `json:"end" xml:"end"`
+	Days             int    `json:"days" xml:"days"`
+	DayChange        string `json:"dayChange" xml:"day_change"`
+	TimeslotDuration string `json:"timeslotDuration" xml:"timeslot_duration"`
+	BaseURL          string `json:"baseUrl" xml:"base_url"`
+	TimeZoneName     string `json:"timeZoneName" xml:"time_zone_name"`
+}
+
+type Track struct {
+	Name string `json:"name" xml:",chardata"`
+}
+
+type Day struct {
+	Date  string `json:"date" xml:"date,attr"`
+	Start string `json:"start" xml:"start"`
+	End   string `json:"end" xml:"end"`
+	Rooms []Room `json:"rooms" xml:"room"`
+}
+
+type Room struct {
+	Name   string  `json:"name" xml:"name,attr"`
+	Events []Event `json:"events" xml:"event"`
+}
+
+type Event struct {
+	ID          int          `json:"id" xml:"id,attr"`
+	GUID        string       `json:"guid" xml:"guid,attr"`
+	Date        string       `json:"date" xml:"date"`
+	Start       string       `json:"start" xml:"start"`
+	Duration    string       `json:"duration" xml:"duration"`
+	Room        string       `json:"room" xml:"room"`
+	URL         string       `json:"url" xml:"url"`
+	Track       string       `json:"track" xml:"track"`
+	Type        string       `json:"type" xml:"type"`
+	Title       string       `json:"title" xml:"title"`
+	Abstract    string       `json:"abstract" xml:"abstract"`
+	Persons     []Person     `json:"persons" xml:"persons>person"`
+	Attachments []Attachment `json:"attachments" xml:"attachments>attachment"`
+	Links       []Link       `json:"links" xml:"links>link"`
+}
+
+type Person struct {
+	ID   int    `json:"id" xml:"id,attr"`
+	Name string `json:"name" xml:",chardata"`
+}
+
+type Attachment struct {
+	Type string `json:"string" xml:"id,attr"`
+	Href string `json:"href" xml:"href,attr"`
+	Name string `json:"name" xml:",chardata"`
+}
+
+type Link struct {
+	Href string `json:"href" xml:"href,attr"`
+	Name string `json:"name" xml:",chardata"`
+}
+
+type service struct {
+	schedule     *Schedule
+	pentabarfUrl string
+	lastUpdated  time.Time
+	lock         sync.Mutex
+}
+
+func NewService(pentabarfUrl string) (Service, error) {
+	service := &service{
+		pentabarfUrl: pentabarfUrl,
+		lastUpdated:  time.Unix(0, 0),
+	}
+
+	err := service.updateSchedule()
+	if err != nil {
+		return nil, fmt.Errorf("could not read schedule from '%s' (is it a valid pentabarf XML file?): %w", pentabarfUrl, err)
+	}
+	return service, nil
+}
+
+func (s *service) GetSchedule() (*Schedule, *time.Time, error) {
+	if s.hasScheduleExpired() {
+		err := s.updateSchedule()
+		if err != nil {
+			return nil, nil, err
+		}
+	}
+
+	return s.schedule, &s.lastUpdated, nil
+}
+
+func (s *service) hasScheduleExpired() bool {
+	expire := s.lastUpdated.Add(15 * time.Minute)
+	return time.Now().After(expire)
+}
+
+func (s *service) updateSchedule() error {
+	s.lock.Lock()
+	defer s.lock.Unlock()
+
+	if !s.hasScheduleExpired() {
+		return nil
+	}
+
+	res, err := http.Get(s.pentabarfUrl)
+	if err != nil {
+		return err
+	}
+
+	reader := bufio.NewReader(res.Body)
+
+	var schedule Schedule
+
+	decoder := xml.NewDecoder(reader)
+	if err := decoder.Decode(&schedule); err != nil {
+		return fmt.Errorf("failed to decode XML: %w", err)
+	}
+
+	s.schedule = &schedule
+	s.lastUpdated = time.Now()
+	return nil
+}