Locked the curves PSD spectrum selection while import has maximal curves count

Author: demvlad

src/graph_imported_curves.js

@@ -105,4 +105,12 @@ export function ImportedCurves(curvesChanged) {
     this.maxY = -Number.MAX_VALUE;
     curvesChanged();
   };
+
+  this.isFull = function() {
+    return this.curvesCount() === maxImportCount;
+  };
+
+  this.isEmpty = function() {
+    return this.curvesCount() === 0;
+  };
 }

src/graph_spectrum.js

@@ -172,7 +172,11 @@ export function FlightLogAnalyser(flightLog, canvas, analyserCanvas) {
            analyser on screen*/
     this.plotSpectrum = function (fieldIndex, curve, fieldName) {
       // Detect change of selected field.... reload and redraw required.
-      if (fftData == null || fieldIndex != fftData.fieldIndex || dataReload) {
+      const isMaxCountOfImportedPSD = GraphSpectrumPlot.isImportedCurvesMaxCount() && userSettings.spectrumType === SPECTRUM_TYPE.POWER_SPECTRAL_DENSITY;
+      const shouldReload = fftData == null ||
+                           fieldIndex != fftData.fieldIndex && !isMaxCountOfImportedPSD || // Lock spectrum data reload while PSD curves import is full
+                           dataReload;
+      if (shouldReload) {
         if (this.shouldAddCurrentSpectrumBeforeReload()) {
           this.addCurrentSpectrumIntoImport();  // The main curve is added into imported list when the second curve is selected for comparison
         }

src/graph_spectrum_plot.js

@@ -1839,6 +1839,9 @@ GraphSpectrumPlot.addCurrentSpectrumIntoImport = function() {
 };
 
 GraphSpectrumPlot.isMultiSpectrum = function() {
-  return this._importedPSD.curvesCount() > 0;
+  return !this._importedPSD.isEmpty();
 };
 
+GraphSpectrumPlot.isImportedCurvesMaxCount = function() {
+  return this._importedPSD.isFull();
+};