2 files changed, 127 insertions, 0 deletions
diff --git a/Software/Visual_Studio/Tango.CSV/CsvDynamicWriter.cs b/Software/Visual_Studio/Tango.CSV/CsvDynamicWriter.cs
new file mode 100644
index 000000000..1c460d5e3
--- /dev/null
+++ b/Software/Visual_Studio/Tango.CSV/CsvDynamicWriter.cs
@@ -0,0 +1,126 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Tango.CSV
+{
+    public class CsvDynamicWriter
+    {
+        private sealed class ColumnInfo
+        {
+            public string Name;
+            public string Default;
+            public int Index;
+            public int CreationOrder;
+        }
+
+        private readonly Dictionary<string, ColumnInfo> _colMap = new Dictionary<string, ColumnInfo>();
+        private readonly List<ColumnInfo> _cols = new List<ColumnInfo>();
+        private int _creationCounter = 0;
+
+        private readonly List<Dictionary<string, string>> _rows = new List<Dictionary<string, string>>();
+        private Dictionary<string, string> _currentRow = new Dictionary<string, string>();
+
+        /// <summary>
+        /// Writes a value to the specified column in the current row.
+        /// If the column does not exist, it is created with the given default value and index.
+        /// Column order in the CSV header is by (Index asc, CreationOrder asc).
+        /// </summary>
+        public void Write(string value, string columnName, string defaultValue, int index)
+        {
+            ColumnInfo col;
+            if (!_colMap.TryGetValue(columnName, out col))
+            {
+                col = new ColumnInfo
+                {
+                    Name = columnName,
+                    Default = defaultValue,
+                    Index = index,
+                    CreationOrder = _creationCounter++
+                };
+                _colMap[columnName] = col;
+                _cols.Add(col);
+
+                // Backfill all prior rows with the column's default.
+                foreach (var row in _rows)
+                {
+                    if (!row.ContainsKey(columnName))
+                        row[columnName] = defaultValue;
+                }
+            }
+            // If the column already exists, we keep the original index/default.
+            // (If you need reindexing, add an explicit method to change col.Index.)
+
+            _currentRow[columnName] = value ?? "";
+        }
+
+        /// <summary>
+        /// Moves to the next row, finalizing the current one.
+        /// Missing cells get their column default value.
+        /// </summary>
+        public void Next()
+        {
+            if (_currentRow == null) _currentRow = new Dictionary<string, string>();
+
+            foreach (var col in _cols)
+            {
+                if (!_currentRow.ContainsKey(col.Name))
+                    _currentRow[col.Name] = col.Default ?? "";
+            }
+
+            _rows.Add(_currentRow);
+            _currentRow = new Dictionary<string, string>();
+        }
+
+        /// <summary>
+        /// Saves the CSV to disk using the column order defined by (Index, CreationOrder).
+        /// </summary>
+        public void Save(string filePath)
+        {
+            // Auto-finalize last row if it has any values.
+            if (_currentRow != null && _currentRow.Count > 0)
+                Next();
+
+            var orderedCols = _cols
+                .OrderBy(c => c.Index)
+                .ThenBy(c => c.CreationOrder)
+                .ToList();
+
+            var sb = new StringBuilder();
+
+            // Header
+            sb.AppendLine(string.Join(",", orderedCols.Select(c => EscapeCsv(c.Name))));
+
+            // Rows
+            foreach (var row in _rows)
+            {
+                var values = new List<string>(orderedCols.Count);
+                for (int i = 0; i < orderedCols.Count; i++)
+                {
+                    var name = orderedCols[i].Name;
+                    string v;
+                    if (!row.TryGetValue(name, out v))
+                    {
+                        // Shouldn't happen (Next() fills), but be defensive.
+                        v = orderedCols[i].Default ?? "";
+                    }
+                    values.Add(EscapeCsv(v));
+                }
+                sb.AppendLine(string.Join(",", values));
+            }
+
+            File.WriteAllText(filePath, sb.ToString(), Encoding.UTF8);
+        }
+
+        private static string EscapeCsv(string input)
+        {
+            if (input == null) return "";
+            if (input.IndexOfAny(new[] { ',', '"', '\n', '\r' }) >= 0)
+                return "\"" + input.Replace("\"", "\"\"") + "\"";
+            return input;
+        }
+    }
+}
diff --git a/Software/Visual_Studio/Tango.CSV/Tango.CSV.csproj b/Software/Visual_Studio/Tango.CSV/Tango.CSV.csproj
index b6743bede..0fc1948a4 100644
--- a/Software/Visual_Studio/Tango.CSV/Tango.CSV.csproj
+++ b/Software/Visual_Studio/Tango.CSV/Tango.CSV.csproj
@@ -81,6 +81,7 @@
     </Compile>
     <Compile Include="CsvDefinition.cs" />
     <Compile Include="CsvDestination.cs" />
+    <Compile Include="CsvDynamicWriter.cs" />
     <Compile Include="CsvFile.cs" />
     <Compile Include="CsvFileLinqExtensions.cs" />
     <Compile Include="CsvFileReader.cs" />