getNext

calendar.js

@@ -1,6 +1,11 @@
 const ICAL = require('ical.js')
 const shows = require('./shows.js')
 
+function max(a, b) {
+  if (a<b) return b
+  return a
+}
+
 /**
  * Represent a schedule (ie: a .ics file)
  */
@@ -21,26 +26,9 @@ class RadioSchedule {
   }
 
   /**
-   * @returns {external:ICAL~Component} if nothing is going on right now, `null` is returned
+   * @returns {RadioShow} tries to get a matching show, or create a new one
    */
-  getNowEvent(now) {
-    var ev_now = this.getEvents().filter(function(vevent) {
-      const ev = new ICAL.Event(vevent)
-      return isNow(ev, now)
-    })
-    if(ev_now.length === 0)
-      return null
-    if(ev_now.length > 1)
-      console.log("More than one event right now?!")
-    return ev_now[0]
-  }
-
-  /**
-   * @returns {RadioShow} if nothing is going on right now, `null` is returned
-   */
-  getNowShow(now) {
-    var ev = this.getNowEvent(now)
-
+  getShowByEvent(ev) {
     if (ev === null) return null
     if (this.radio !== undefined) {
       const showid = RadioSchedule.veventGetShowID(ev)
@@ -54,19 +42,59 @@ class RadioSchedule {
   }
 
   /**
-   * @todo To be implemented
+   * @returns {external:ICAL~Component} if nothing is going on right now, `null` is returned
+   */
+  getNowEvent(now) {
+    var ev_now = this.getEvents().filter(function(vevent) {
+      const ev = new ICAL.Event(vevent)
+      return isNow(ev, now)
+    })
+    ev_now.sort((e1, e2) => { return this.veventGetPriority(e1) - this.veventGetPriority(e2) })
+    if(ev_now.length === 0)
+      return null
+    return ev_now[0]
+  }
+
+  /**
+   * @returns {RadioShow} if nothing is going on right now, `null` is returned
+   */
+  getNowShow(now) {
+    const ev = this.getNowEvent(now)
+    return this.getShowByEvent(ev)
+  }
+
+  /**
+   * @returns {NextEvent} if there is none, `null` is returned
    */
   getNextEvent(now) {
-    // XXX
+    var nowEvent = this.getNowEvent(now)
+    let future_events = this.getEvents().filter((e) => { return e != nowEvent })
+      .map((e) => {
+        const vEvent = new ICAL.Event(e)
+        return {event: e, time: getNext(vEvent, now)}
+      })
+      .filter((x) => { return x.time !== null && x.time !== undefined })
+    // since ".sort()" is guaranteed to be stable, we can sort by priority, then by date, so that two events
+    // starting at the same time will be sorted observing priority
+    future_events.sort((x1, x2) => this.veventGetPriority(x1.event) - this.veventGetPriority(x2.event))
+    future_events.sort((x, y) => x.time.toUnixTime() - y.time.toUnixTime())
+
+    if (future_events.length === 0) {
+      return null
+    }
+    return future_events[0]
   }
 
 
   /**
-   * @todo To be implemented
-   * @returns {NextShow} if there is no next show, nothing will be returned
+   * @returns {NextShow} if there is no next show, null will be returned
    */
   getNextShow(now) {
-    // XXX
+    const next = this.getNextEvent(now)
+    if (next === null) return null
+    const ev = next.event
+    const show = this.getShowByEvent(ev)
+    return {show: show, time: next.time}
   }
   static veventGetSummary(vevent) {
       return vevent.getFirstProperty('summary').getFirstValue()
@@ -75,6 +103,24 @@ class RadioSchedule {
       return RadioSchedule.veventGetSummary(vevent)  // XXX: X-Show-ID
   }
 
+  /**
+   * @return {integer} a normalized version of priority, easier to compare
+   */
+  veventGetPriority(ev) {
+    const prop = ev.getFirstProperty('priority')
+    let prio;
+    if (prop === null) {
+      prio = null
+    } else {
+      prio = prop.getFirstValue()
+    }
+    if (prio === null || prio === 0) {
+      prio = 100
+    }
+    return prio
+  }
+
+
 }
 
 
@@ -85,7 +131,7 @@ function isNow(vEvent, now) {
     if (vEvent.isRecurring()) {
           return isNowRecurring(vEvent, now)
         }
-    return (now < vEvent.endDate) && (now > event.startDate);
+    return (now < vEvent.endDate) && (now > vEvent.startDate);
 }
 
 
@@ -105,6 +151,49 @@ function isNowRecurring(vEvent, now) {
 }
 
 
+/*
+ * @private
+ * @param {external:ICAL~Component} vEvent a _recurring_ vEvent
+ * @param {external:ICAL~Time} [now]
+ * @return {external:ICAL~Time} first future occurrence of this event
+ */
+function getNext(vEvent, now) {
+  if (now === undefined) {
+    now = ICAL.Time.now()
+  }
+  if (vEvent.isRecurring()) {
+    return getNextRecurring(vEvent, now)
+  }
+  if (vEvent.endDate > now) {
+    const val = max(now, vEvent.startDate)
+    return val
+  }
+  return null
+}
+
+/*
+ * @private
+ * @param {external:ICAL~Component} vEvent a _recurring_ vEvent
+ * @param {external:ICAL~Time} now
+ * @return {external:ICAL~Time} first future occurrence of this event
+ */
+function getNextRecurring(vEvent, now) {
+  var expand = vEvent.iterator(vEvent.startDate)
+  var next, next_end;
+
+  while ((next = expand.next())) {
+    const start = next.clone()
+    next_end = start.clone()
+    next_end.addDuration(vEvent.duration)
+    if (next_end <= now) {
+      continue
+    }
+    return max(start, now)
+  }
+  return null
+}
+
+
 async function get(manifest) {
   if (manifest.scheduleURL) {
     let resp = null
@@ -151,6 +240,12 @@ module.exports = {
  * @property {external:ICAL~Time} time When it will start
  */
 
+/**
+ * @typedef {Object} NextEvent
+ * @property {RadioShow} event The next show scheduled
+ * @property {external:ICAL~Time} time When it will start
+ */
+
 /**
  * @external ICAL
  * @see https://mozilla-comm.github.io/ical.js/api/index.html

test/example-full-ondarossa.test.js

@@ -72,6 +72,35 @@ describe('examples/' + exampleName, () => {
       assert.equal(show.getFeed(), testFeed)
     })
 
+    it('monday at 7PM, "Entropia Massima" is next', async () => {
+      const rm = await radiomanifest.get(url)
+      const rs = rm.getSchedule()
+      const now = new ICAL.Time({
+            year: 2022,
+            month: 1,
+            day: 31,
+            hour: 19,
+            minute: 10,
+            second: 0,
+            isDate: false
+        },
+      );
+      const vevent = rs.getNowEvent(now)
+      assert.notEqual(vevent, null)
+      const show = rs.getNowShow(now)
+      assert.notEqual(show, null)
+      assert.equal(show.getName(), 'Baraonda')
+
+      const next_event = rs.getNextEvent(now)
+      assert.notEqual(next_event, null)
+      assert.notEqual(next_event.event, null)
+      const next_show = rs.getNextShow(now)
+      assert.notEqual(next_show, null)
+      assert.notEqual(next_show.show, null)
+      assert.equal(next_show.show.getName(), testShowName)
+      assert.equal(next_show.show.getFeed(), testFeed)
+    })
+
   })
 
 })