From 7e7630579cdd3173698fca75d4eb9f74da41df47 Mon Sep 17 00:00:00 2001
From: John Andrews <john@reven.nz>
Date: Thu, 21 Jul 2022 09:10:48 +1200
Subject: [PATCH] adding error handling around videoinfo and making it readonly
 for ffmpeg builder model

---
 .../FfmpegBuilderNodes/FfmpegBuilderNode.cs       | 15 ++++-----------
 .../FfmpegBuilderNodes/FfmpegBuilderStart.cs      | 15 ++++++++++++++-
 .../FfmpegBuilderNodes/Models/FfmpegModel.cs      | 11 ++++++++---
 3 files changed, 26 insertions(+), 15 deletions(-)

diff --git a/VideoNodes/FfmpegBuilderNodes/FfmpegBuilderNode.cs b/VideoNodes/FfmpegBuilderNodes/FfmpegBuilderNode.cs
index 053444c0..fd82024d 100644
--- a/VideoNodes/FfmpegBuilderNodes/FfmpegBuilderNode.cs
+++ b/VideoNodes/FfmpegBuilderNodes/FfmpegBuilderNode.cs
@@ -5,7 +5,7 @@ namespace FileFlows.VideoNodes.FfmpegBuilderNodes
 {
     public abstract class FfmpegBuilderNode: EncodingNode
     {
-        private const string MODEL_KEY = "FfmpegBuilderModel";
+        protected const string MODEL_KEY = "FfmpegBuilderModel";
 
         public override int Inputs => 1;
         public override int Outputs => 1;
@@ -13,16 +13,6 @@ namespace FileFlows.VideoNodes.FfmpegBuilderNodes
         public override FlowElementType Type => FlowElementType.BuildPart;
         public override string HelpUrl => "https://docs.fileflows.com/plugins/video-nodes/ffmpeg-builder";
 
-        private Dictionary<string, object> _Variables;
-        public override Dictionary<string, object> Variables => _Variables;
-        public FfmpegBuilderNode()
-        {
-            _Variables = new Dictionary<string, object>()
-            {
-                { MODEL_KEY, new FfmpegModel() }
-            };
-        }
-
 
         public override bool PreExecute(NodeParameters args)
         {
@@ -32,6 +22,9 @@ namespace FileFlows.VideoNodes.FfmpegBuilderNodes
             if(this is FfmpegBuilderStart == false && Model == null)
                 throw new Exception("FFMPEG Builder Model not set, you must add and use the \"FFMPEG Builder Start\" node first");
 
+            if (this is FfmpegBuilderStart == false && Model.VideoInfo == null)
+                throw new Exception("FFMPEG Builder VideoInfo is null");
+
             return true;
         }
 
diff --git a/VideoNodes/FfmpegBuilderNodes/FfmpegBuilderStart.cs b/VideoNodes/FfmpegBuilderNodes/FfmpegBuilderStart.cs
index 694eba8d..4737610d 100644
--- a/VideoNodes/FfmpegBuilderNodes/FfmpegBuilderStart.cs
+++ b/VideoNodes/FfmpegBuilderNodes/FfmpegBuilderStart.cs
@@ -1,4 +1,6 @@
-namespace FileFlows.VideoNodes.FfmpegBuilderNodes;
+using FileFlows.VideoNodes.FfmpegBuilderNodes.Models;
+
+namespace FileFlows.VideoNodes.FfmpegBuilderNodes;
 
 /// <summary>
 /// Node that starts the FFMPEG Builder
@@ -30,6 +32,17 @@ public class FfmpegBuilderStart: FfmpegBuilderNode
     public override FlowElementType Type => FlowElementType.BuildStart;
 
 
+
+    private Dictionary<string, object> _Variables;
+    public override Dictionary<string, object> Variables => _Variables;
+    public FfmpegBuilderStart()
+    {
+        _Variables = new Dictionary<string, object>()
+        {
+            { MODEL_KEY, new FfmpegModel(new VideoInfo()) }
+        };
+    }
+
     /// <summary>
     /// Executes the node
     /// </summary>
diff --git a/VideoNodes/FfmpegBuilderNodes/Models/FfmpegModel.cs b/VideoNodes/FfmpegBuilderNodes/Models/FfmpegModel.cs
index bce17906..de460c6c 100644
--- a/VideoNodes/FfmpegBuilderNodes/Models/FfmpegModel.cs
+++ b/VideoNodes/FfmpegBuilderNodes/Models/FfmpegModel.cs
@@ -56,12 +56,17 @@
         /// <summary>
         /// Gets or sets the video information for this video file
         /// </summary>
-        public VideoInfo VideoInfo { get; set; }
+        public VideoInfo VideoInfo => _VideoInfo;
+        readonly VideoInfo _VideoInfo;
+
+        public FfmpegModel(VideoInfo info)
+        {
+            this._VideoInfo = info;
+        }
 
         internal static FfmpegModel CreateModel(VideoInfo info)
         {
-            var model = new FfmpegModel();
-            model.VideoInfo = info;
+            var model = new FfmpegModel(info);
             model.InputFiles.Add(info.FileName);
             foreach (var item in info.VideoStreams.Select((stream, index) => (stream, index)))
             {