If date in file name, use that date

Helpers/Utilities.cs

@@ -1,6 +1,9 @@
 
+using System;
+using System.Globalization;
 using System.Text.Json;
 using System.Text.Json.Serialization;
+using System.Text.RegularExpressions;
 
 namespace ReceiptPDFBuilders.Helpers;
 
@@ -15,4 +18,21 @@ class Utilities
         };
         return opts;
     }
+
+    public static DateOnly? CheckValidDateInString(string str)
+    {
+        // https://stackoverflow.com/a/14918404/3938401
+        var rgx = new Regex(@"\d{4}-\d{2}-\d{2}");
+        var mat = rgx.Match(str);
+        if (mat.Success)
+        {
+            var dtStr = mat.ToString();
+            string[] formats = ["yyyy-MM-dd"];
+            DateTime parsedDateTime;
+            var didWork = DateTime.TryParseExact(dtStr, formats, CultureInfo.InvariantCulture,
+                                        DateTimeStyles.None, out parsedDateTime);
+            return didWork ? DateOnly.FromDateTime(parsedDateTime) : null;
+        }
+        return null;
+    }
 }

ViewModels/MainViewModel.cs

@@ -219,11 +219,11 @@ class MainViewModel : BaseViewModel, IFontResolver
     {
         if (!string.IsNullOrWhiteSpace(filePath) && File.Exists(filePath) && !filePath.EndsWith(".DS_Store"))
         {
-            // TODO: if date in file name, pull out that date instead
+            var date = Utilities.CheckValidDateInString(filePath);
             ReportFiles.Add(new ReportFile()
             {
                 Title = Path.GetFileName(filePath),
-                ReceiptDateTime = File.GetCreationTime(filePath),
+                ReceiptDateTime = date.HasValue ? date.Value.ToDateTime(TimeOnly.MinValue) : File.GetCreationTime(filePath),
                 Notes = "",
                 FilePath = filePath,
             });