Add comparison function for timecodesArrays

This makes the function reuseable by other methods besides updates.

src/jsx/KBRG/ThumbnailMetadata.js

@@ -271,18 +271,10 @@ ThumbnailMetadata.prototype.updateFromTimecodes = function (updates, enableMedia
  return false;
  }
 
- for (var i = 0; i < updates.length; i++) {
- if (!updates[i].fileTC || !(updates[i].fileTC instanceof Timecode)) {
- continue;
- }
+ var update = this.compareTimecode(updates, enableMediaStartComparison);
 
- if (updates[i].name.toUpperCase() === this.filename.toUpperCase() &&
- (enableMediaStartComparison ?
- updates[i].fileTC === this.timecodeMetadata.startTime :
- true) &&
- updates[i].audioTC instanceof Timecode) {
- return this.updateFromTimecode(updates[i].audioTC, overrideFramerate);
- }
+ if (update) {
+ return this.updateFromTimecode(update.audioTC, overrideFramerate);
  }
 
  return false;
@@ -319,7 +311,7 @@ ThumbnailMetadata.prototype.updateTimecodeMetadata = function (newStartTime) {
 
  if (this.audioMetadata) {
  this.audioMetadata.samples = this.timecodeMetadata.startTime.toSamples(this.audioMetadata.sampleFrequency);
- 
+
  this.xmp.setProperty(XMPConst.NS_BWF, "timeReference",
  this.audioMetadata.samples.toString(), XMPConst.STRING);
  }
@@ -329,6 +321,28 @@ ThumbnailMetadata.prototype.updateTimecodeMetadata = function (newStartTime) {
  return false;
 }
 
+/**
+ * Loops through every update entitiy until a matching filename and or mediastart is found and returns matching timecode structure (not object)
+ * @param {array} timecodes 
+ * @param {boolean} enableMediaStartComparison 
+ * @returns {object|undefined} on successfull match returns the matching object in the timecodes array
+ */
+ThumbnailMetadata.prototype.compareTimecode = function (timecodes, enableMediaStartComparison) {
+ for (var i = 0; i < timecodes.length; i++) {
+ if (timecodes[i].fileTC
+ && timecodes[i].fileTC instanceof Timecode
+ && timecodes[i].name
+ && timecodes[i].name.toUpperCase() === this.filename.toUpperCase()
+ && (enableMediaStartComparison ?
+ timecodes[i].fileTC === this.timecodeMetadata.startTime :
+ true) &&
+ timecodes[i].audioTC instanceof Timecode) {
+ return timecodes[i];
+ }
+ }
+ return undefined;
+}
+
 /**
  * If an XMPMeta object is attached to a ThumbnailMetadata object it attempts to write the new metadata to the thumbnail.
  * Basically a wrapper.