NIT aggregation support

Author: phpbg

examples/print-with-context.php

@@ -67,6 +67,9 @@
 $dvbPsiParser->on('eit', function ($eit) use ($globalContext) {
     $globalContext->addEit($eit);
 });
+$dvbPsiParser->on('nit', function ($nit) use ($globalContext) {
+    $globalContext->addNit($nit);
+});
 $dvbPsiParser->on('pmt', function ($pmt) use ($streamContext) {
     $streamContext->addPmt($pmt);
 });

src/Context/GlobalContext.php

@@ -26,16 +26,42 @@
 
 namespace PhpBg\DvbPsi\Context;
 
-
 use Evenement\EventEmitter;
 use PhpBg\DvbPsi\Tables\Eit;
+use PhpBg\DvbPsi\Tables\Nit;
 
 class GlobalContext extends EventEmitter
 {
     protected $eitByNetworks = [];
 
+    /**
+     * @var NitAggregator[]
+     */
+    protected $nitByNetworks = [];
+
+    /**
+     * @param Nit $nit
+     * @throws \PhpBg\DvbPsi\Exception
+     */
+    public function addNit(Nit $nit)
+    {
+        if ($nit->currentNextIndicator !== 1) {
+            return;
+        }
+        if (!isset($this->nitByNetworks[$nit->networkId])) {
+            $this->nitByNetworks[$nit->networkId] = new NitAggregator();
+        }
+        $nitComplete = $this->nitByNetworks[$nit->networkId]->add($nit);
+        if ($nitComplete) {
+            $this->emit('nit', [$this->nitByNetworks[$nit->networkId]]);
+        }
+    }
+
     public function addEit(Eit $eit)
     {
+        if ($eit->currentNextIndicator !== 1) {
+            return;
+        }
         if (!isset($this->eitByNetworks[$eit->originalNetworkId])) {
             $this->eitByNetworks[$eit->originalNetworkId] = [];
         }
@@ -75,18 +101,19 @@ public function getAllEvents()
     public function __toString()
     {
         $str = '';
-        if (!empty($this->eitByNetworks)) {
-            foreach ($this->eitByNetworks as $networkId => $transportStreams) {
-                $str .= sprintf("Network: %d (0x%x)\n", $networkId, $networkId);
-                foreach ($transportStreams as $transportStream => $services) {
-                    $str .= sprintf("\tTransport Stream: %d (0x%x)\n", $transportStream, $transportStream);
-                    foreach ($services as $service => $eitAggregator) {
-                        $str .= sprintf("\t\tService: %d (0x%x)\n", $service, $service);
-                        $str .= (string)$eitAggregator;
-                    }
+        foreach ($this->eitByNetworks as $networkId => $transportStreams) {
+            $str .= sprintf("Network: %d (0x%x)\n", $networkId, $networkId);
+            foreach ($transportStreams as $transportStream => $services) {
+                $str .= sprintf("\tTransport Stream: %d (0x%x)\n", $transportStream, $transportStream);
+                foreach ($services as $service => $eitAggregator) {
+                    $str .= sprintf("\t\tService: %d (0x%x)\n", $service, $service);
+                    $str .= (string)$eitAggregator;
                 }
             }
         }
+        foreach ($this->nitByNetworks as $networkId => $nitAggregator) {
+            echo "$nitAggregator\n";
+        }
         return $str;
     }
 }

src/Context/NitAggregator.php

@@ -0,0 +1,87 @@
+<?php
+
+/**
+ * MIT License
+ *
+ * Copyright (c) 2018 Samuel CHEMLA
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+namespace PhpBg\DvbPsi\Context;
+
+use PhpBg\DvbPsi\Exception;
+use PhpBg\DvbPsi\Tables\Nit;
+
+/**
+ * Class NitAggregator
+ * Aggregates all NIT segments
+ */
+class NitAggregator
+{
+    public $networkId;
+
+    /**
+     * @var Nit[]
+     */
+    public $segments = [];
+
+    protected $version;
+
+    /**
+     * Aggregate a new EIT
+     *
+     * @param Nit $nit
+     * @throws Exception
+     * @return bool Return true if the EIT was unknown and has been aggregated, false otherwise
+     */
+    public function add(Nit $nit): bool
+    {
+        if (!isset($this->networkId)) {
+            $this->networkId = $nit->networkId;
+        } else {
+            if ($this->networkId !== $nit->networkId) {
+                throw new Exception("NIT and aggregator mismatch");
+            }
+        }
+        if (!isset($this->version) || $nit->versionNumber > $this->version || ($nit->versionNumber === 0 && $this->version === 31)) {
+            // Version update (or initial collection of nit)
+            $this->version = $nit->versionNumber;
+            $this->segments = [];
+        }
+        if (!isset($this->segments[$nit->sectionNumber])) {
+            $this->segments[$nit->sectionNumber] = $nit;
+        }
+        if (count($this->segments) >= $nit->lastSectionNumber + 1) {
+            // NIT aggregation is complete
+            return true;
+        }
+        return false;
+    }
+
+
+    public function __toString()
+    {
+        $str = '';
+        foreach ($this->segments as $segment) {
+            echo "{$segment}\n";
+        }
+        return $str;
+    }
+}