Initial commit

NHSE.Core/Save/Meta/EncryptedFilePair.cs

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+using System;
+using System.IO;
+using System.Text;
+
+namespace NHSE.Core
+{
+    public abstract class EncryptedFilePair
+    {
+        public readonly byte[] Data;
+        public readonly byte[] Header;
+
+        public readonly FileHeaderInfo Info;
+
+        public readonly string DataPath;
+        public readonly string HeaderPath;
+        public readonly string NameData;
+        public readonly string NameHeader;
+
+        protected EncryptedFilePair(string folder, string name)
+        {
+            NameData = $"{name}.dat";
+            NameHeader = $"{name}Header.dat";
+            var hdr = Path.Combine(folder, NameHeader);
+            var dat = Path.Combine(folder, NameData);
+
+            var hd = File.ReadAllBytes(hdr);
+            var md = File.ReadAllBytes(dat);
+
+            var decrypted = Encryption.Decrypt(hd, md);
+
+            Header = hd;
+            Data = decrypted;
+            DataPath = dat;
+            HeaderPath = hdr;
+
+            Info = Header.Slice(0, FileHeaderInfo.SIZE).ToClass<FileHeaderInfo>();
+        }
+
+        public void Save(uint seed)
+        {
+            var encrypt = Encryption.Encrypt(Data, seed, Header);
+            File.WriteAllBytes(DataPath, encrypt.Data);
+            File.WriteAllBytes(HeaderPath, encrypt.Header);
+        }
+
+        public void Hash()
+        {
+            var ver = Info.GetKnownRevisionIndex();
+            var hash = RevisionChecker.HashInfo[ver];
+            var details = hash.GetFile(NameData);
+            if (details == null)
+                throw new ArgumentNullException(nameof(NameData));
+            foreach (var h in details.HashRegions)
+                Murmur3.UpdateMurmur32(Data, h.HashOffset, h.BeginOffset, (uint)h.Size);
+        }
+
+        public string GetString(int offset, int maxLength)
+        {
+            var str = Encoding.Unicode.GetString(Data, offset, maxLength * 2);
+            return StringUtil.TrimFromZero(str);
+        }
+
+        public static byte[] GetBytes(string value, int maxLength)
+        {
+            if (value.Length > maxLength)
+                value = value.Substring(0, maxLength);
+            else if (value.Length < maxLength)
+                value = value.PadRight(maxLength, '\0');
+            return Encoding.Unicode.GetBytes(value);
+        }
+    }
+}