(ACTGS): archive variation.

ArcFormats/Actgs/ArcCG.cs

@@ -26,7 +26,10 @@
 using System;
 using System.Collections.Generic;
 using System.ComponentModel.Composition;
+using System.IO;
 using System.Linq;
+using GameRes.Compression;
+using GameRes.Utility;
 
 namespace GameRes.Formats.Actgs
 {
@@ -41,7 +44,8 @@ namespace GameRes.Formats.Actgs
 
         public override ArcFile TryOpen (ArcView file)
         {
-            var key = FindKey (file);
+            var pattern = file.View.ReadBytes (4, 8);
+            var key = FindKey (4, pattern);
             if (null == key)
                 return null;
             uint signature_key = key.ToUInt32 (0);
@@ -61,10 +65,9 @@ namespace GameRes.Formats.Actgs
             }
         }
 
-        byte[] FindKey (ArcView file)
+        internal byte[] FindKey (int offset, byte[] pattern)
         {
-            var pattern = file.View.ReadBytes (4, 8);
+            return Array.Find (KnownKeys, k => KeySequence (k).Skip (offset).Take (pattern.Length).SequenceEqual (pattern));
-            return Array.Find (KnownKeys, k => KeySequence (k).Skip (4).Take (8).SequenceEqual (pattern));
         }
 
         internal static IEnumerable<byte> KeySequence (byte[] key)
@@ -76,4 +79,64 @@ namespace GameRes.Formats.Actgs
             }
         }
     }
+
+    [Export(typeof(ArchiveFormat))]
+    public class ArcCgOpener : CgOpener
+    {
+        public override string         Tag { get { return "CG/ACTGS/2"; } }
+        public override string Description { get { return "ACTGS engine resource archive"; } }
+        public override uint     Signature { get { return 0; } }
+        public override bool  IsHierarchic { get { return false; } }
+        public override bool      CanWrite { get { return false; } }
+
+        public override ArcFile TryOpen (ArcView file)
+        {
+            if (file.MaxOffset <= 0x1020)
+                return null;
+            int count = file.View.ReadInt32 (0);
+            if (!IsSaneCount (count))
+                return null;
+            var pattern = file.View.ReadBytes (0x1018, 8);
+            var key = FindKey (0x18, pattern);
+            if (null == key)
+                return null;
+            var dir = new List<Entry> (count);
+            var buffer = new byte[0x20];
+            long offset = 0x1000;
+            while (file.View.Read (offset, buffer, 0, 0x20) == 0x20)
+            {
+                offset += 0x20;
+                Decrypt (buffer, 0, 0x20, key);
+                uint size = buffer.ToUInt32 (0);
+                var name = Binary.GetCString (buffer, 4);
+                var entry = FormatCatalog.Instance.Create<Entry> (name);
+                entry.Offset = offset;
+                entry.Size = size;
+                if (!entry.CheckPlacement (file.MaxOffset))
+                    return null;
+                offset += (size + 0xFu) & ~0xFu;
+                dir.Add (entry);
+            }
+            if (0 == dir.Count)
+                return null;
+            return new ActressArchive (file, this, dir, key);
+        }
+
+        public override Stream OpenEntry (ArcFile arc, Entry entry)
+        {
+            var actarc = arc as ActressArchive;
+            if (null == actarc || null == actarc.Key)
+                return base.OpenEntry (arc, entry);
+            var header = ReadEntryHeader (actarc, entry);
+            Stream input;
+            if (entry.Size <= 0x20)
+                input = new BinMemoryStream (header, entry.Name);
+            else
+                input = new PrefixStream (header, arc.File.CreateStream (entry.Offset+0x20, entry.Size-0x20));
+            if (header.AsciiEqual ("BM"))
+                return input;
+            input.Position = 4;
+            return new LzssStream (input);
+        }
+    }
 }

ArcFormats/Actgs/ArcDAT.cs

@@ -125,10 +125,7 @@ namespace GameRes.Formats.Actgs
                 var input = arc.File.CreateStream (entry.Offset+12, packed_size);
                 return new LzssStream (input);
             }
-            uint length = Math.Min (entry.Size, 0x20u);
+            var header = ReadEntryHeader (actarc, entry);
-            var header = new byte[length];
-            arc.File.View.Read (entry.Offset, header, 0, length);
-            Decrypt (header, 0, (int)length, actarc.Key);
             if (entry.Size <= 0x20)
                 return new BinMemoryStream (header, entry.Name);
             var rest = arc.File.CreateStream (entry.Offset+0x20, entry.Size-0x20);
@@ -150,6 +147,14 @@ namespace GameRes.Formats.Actgs
             }
         }
 
+        internal byte[] ReadEntryHeader (ActressArchive arc, Entry entry)
+        {
+            uint length = Math.Min (entry.Size, 0x20u);
+            var header = arc.File.View.ReadBytes (entry.Offset, length);
+            Decrypt (header, 0, header.Length, arc.Key);
+            return header;
+        }
+
         public override ResourceScheme Scheme
         {
             get { return new ActressScheme { KnownKeys = KnownKeys }; }