feat: start working on part 1 solution

09/MirageMaintenance/Program.cs

@@ -1,2 +1,71 @@
-// See https://aka.ms/new-console-template for more information
-Console.WriteLine("Hello, World!");
+namespace MirageMaintenance;
+
+class Program
+{
+  public static async Task<int> Main(string[] args)
+  {
+    return await Task.FromResult(0);
+  }
+}
+
+public class OasisReport(
+  List<ValueHistory> valueHistories
+)
+{
+  public List<ValueHistory> ValueHistories { get; init; } = valueHistories;
+
+  public static OasisReport Parse(string[] oasisReportInput)
+  {
+    var valueHistories = new List<ValueHistory>();
+
+    foreach (var line in oasisReportInput)
+    {
+      var values = line
+        .Split(' ', StringSplitOptions.TrimEntries | StringSplitOptions.RemoveEmptyEntries)
+        .Select(long.Parse)
+        .ToList();
+
+      var valueHistory = new ValueHistory(values);
+      valueHistories.Add(valueHistory);
+    }
+
+    return new OasisReport(valueHistories);
+  }
+}
+
+public class ValueHistory(
+  List<long> values
+)
+{
+  List<long> Values { get; init; } = values;
+
+  public List<long> CalculateDifferences(List<long> values) => Enumerable
+    .Range(0, values.Count - 1)
+    .Select(i => values[i + 1] - values[i])
+    .ToList();
+
+  public List<List<long>> CalculateHistory()
+  {
+    var allHistoricalValues = new List<List<long>>();
+    var currentValues = Values;
+
+    while (
+      allHistoricalValues.Count is 0 ||
+      allHistoricalValues.Last().Sum() is not 0
+    )
+    {
+      var historicalValues = CalculateDifferences(currentValues);
+      allHistoricalValues.Add(historicalValues);
+      currentValues = historicalValues;
+    }
+
+    return allHistoricalValues;
+  }
+
+  public long CalculateNextValue()
+  {
+    var historicalValues = CalculateHistory();
+    var values = historicalValues.Prepend(Values).ToList();
+    return 0;
+  }
+}