From 6cfbe0ff880506003a135236f7143a67085ab2fb Mon Sep 17 00:00:00 2001
From: Evan Harris <eharris@puremagic.com>
Date: Sat, 29 Jun 2019 14:28:39 -0500
Subject: [PATCH] Moved expected content length calculation to
 TranscodingService

---
 .../player/controller/StreamController.java   | 23 ----------
 .../player/service/TranscodingService.java    | 43 ++++++++++++++++++-
 2 files changed, 42 insertions(+), 24 deletions(-)

diff --git a/airsonic-main/src/main/java/org/airsonic/player/controller/StreamController.java b/airsonic-main/src/main/java/org/airsonic/player/controller/StreamController.java
index 050791bb..29dbb31c 100644
--- a/airsonic-main/src/main/java/org/airsonic/player/controller/StreamController.java
+++ b/airsonic-main/src/main/java/org/airsonic/player/controller/StreamController.java
@@ -329,29 +329,6 @@ public class StreamController {
         return null;
     }
 
-    private long getFileLength(TranscodingService.Parameters parameters) {
-        MediaFile file = parameters.getMediaFile();
-
-        if (!parameters.isDownsample() && !parameters.isTranscode()) {
-            return file.getFileSize();
-        }
-        Integer duration = file.getDurationSeconds();
-        Integer maxBitRate = parameters.getMaxBitRate();
-
-        if (duration == null) {
-            LOG.warn("Unknown duration for " + file + ". Unable to estimate transcoded size.");
-            return file.getFileSize();
-        }
-
-        if (maxBitRate == null) {
-            LOG.error("Unknown bit rate for " + file + ". Unable to estimate transcoded size.");
-            return file.getFileSize();
-        }
-
-        // Over-estimate size a bit (2 seconds) so don't cut off early in case of small calculation differences
-        return (duration + 2) * (long)maxBitRate * 1000L / 8L;
-    }
-
     @Nullable
     private HttpRange getRange(HttpServletRequest request, Integer fileDuration, Long fileSize) {
 
diff --git a/airsonic-main/src/main/java/org/airsonic/player/service/TranscodingService.java b/airsonic-main/src/main/java/org/airsonic/player/service/TranscodingService.java
index a98ca944..9c2a143a 100644
--- a/airsonic-main/src/main/java/org/airsonic/player/service/TranscodingService.java
+++ b/airsonic-main/src/main/java/org/airsonic/player/service/TranscodingService.java
@@ -216,6 +216,7 @@ public class TranscodingService {
         }
 
         parameters.setMaxBitRate(maxBitRate);
+        parameters.setExpectedLength(getExpectedLength(parameters));
         parameters.setRangeAllowed(isRangeAllowed(parameters));
         return parameters;
     }
@@ -488,6 +489,32 @@ public class TranscodingService {
         return matches != null && matches.length > 0;
     }
 
+    /**
+     * Returns the length (or predicted/expected length) of a (possibly padded) media stream
+     */
+    private Long getExpectedLength(Parameters parameters) {
+        MediaFile file = parameters.getMediaFile();
+
+        if (!parameters.isDownsample() && !parameters.isTranscode()) {
+            return file.getFileSize();
+        }
+        Integer duration = file.getDurationSeconds();
+        Integer maxBitRate = parameters.getMaxBitRate();
+
+        if (duration == null) {
+            LOG.warn("Unknown duration for " + file + ". Unable to estimate transcoded size.");
+            return null;
+        }
+
+        if (maxBitRate == null) {
+            LOG.error("Unknown bit rate for " + file + ". Unable to estimate transcoded size.");
+            return null;
+        }
+
+        // Over-estimate size a bit (2 seconds) so don't cut off early in case of small calculation differences
+        return (duration + 2) * (long)maxBitRate * 1000L / 8L;
+    }
+
     private boolean isRangeAllowed(Parameters parameters) {
         Transcoding transcoding = parameters.getTranscoding();
         List<String> steps = Arrays.asList();
@@ -498,7 +525,12 @@ public class TranscodingService {
             steps = Arrays.asList(settingsService.getDownsamplingCommand());
         }
         else {
-            return true;  // neither transcoding or downsampling
+            return true;  // neither transcoding nor downsampling
+        }
+
+        // Verify that were able to predict the length
+        if (parameters.getExpectedLength() == null) {
+            return false;
         }
 
         // Check if last configured step uses the bitrate, if so, range should be pretty safe
@@ -540,6 +572,7 @@ public class TranscodingService {
 
     public static class Parameters {
         private boolean downsample;
+        private Long expectedLength;
         private boolean rangeAllowed;
         private final MediaFile mediaFile;
         private final VideoTranscodingSettings videoTranscodingSettings;
@@ -575,6 +608,14 @@ public class TranscodingService {
             this.rangeAllowed = rangeAllowed;
         }
 
+        public Long getExpectedLength() {
+            return this.expectedLength;
+        }
+
+        public void setExpectedLength(Long expectedLength) {
+            this.expectedLength = expectedLength;
+        }
+
         public void setTranscoding(Transcoding transcoding) {
             this.transcoding = transcoding;
         }