From 85962ae01fbf24a0bf67ad25e325450d3f49a4cc Mon Sep 17 00:00:00 2001
From: ManicSteiner <manicsteiner@outlook.com>
Date: Wed, 6 Dec 2023 23:58:24 +0800
Subject: [PATCH] feat: add support of Shin Hayarigami PS3 archive

---
 ArcFormats/ArcFormats.csproj     |  1 +
 ArcFormats/NipponIchi/ArcCASN.cs | 49 ++++++++++++++++++++++++++++++++
 2 files changed, 50 insertions(+)
 create mode 100644 ArcFormats/NipponIchi/ArcCASN.cs

diff --git a/ArcFormats/ArcFormats.csproj b/ArcFormats/ArcFormats.csproj
index 77a19a93..512fe8ce 100644
--- a/ArcFormats/ArcFormats.csproj
+++ b/ArcFormats/ArcFormats.csproj
@@ -172,6 +172,7 @@
     <Compile Include="MAGES\ArcARC20.cs" />
     <Compile Include="MAGES\ArcLoveOnce.cs" />
     <Compile Include="Mugi\ArcBIN.cs" />
+    <Compile Include="NipponIchi\ArcCASN.cs" />
     <Compile Include="NScripter\Script.cs" />
     <Compile Include="Psp\ArcQPK.cs" />
     <Compile Include="ScrPlayer\ImageIMG.cs" />
diff --git a/ArcFormats/NipponIchi/ArcCASN.cs b/ArcFormats/NipponIchi/ArcCASN.cs
new file mode 100644
index 00000000..fe2eb2c7
--- /dev/null
+++ b/ArcFormats/NipponIchi/ArcCASN.cs
@@ -0,0 +1,49 @@
+using GameRes.Utility;
+using System.Collections.Generic;
+using System.ComponentModel.Composition;
+
+namespace GameRes.Formats.NipponIchi
+{
+    [Export(typeof(ArchiveFormat))]
+    public class CASNOpener : ArchiveFormat
+    {
+        public override string Tag { get { return "DAT/CASN ShinHayarigami"; } }
+        public override string Description { get { return "Nippon Ichi Shin Hayarigami PS3 resource archive"; } }
+        public override uint Signature { get { return 0x4E534143; } } // 'CASN'
+        public override bool IsHierarchic { get { return false; } }
+        public override bool CanWrite { get { return false; } }
+
+        public override ArcFile TryOpen(ArcView file)
+        {
+            int count = Binary.BigEndian(file.View.ReadUInt16(6));
+            long index_offset = count * 10 + 30; //actually count*10 + 28, ignored two bytes of 000C or 000B
+            var dir = new List<Entry>(count);
+            for (int i = 0; i < count; ++i)
+            {
+
+                uint fstart = Binary.BigEndian(file.View.ReadUInt32(index_offset));
+                uint flength = Binary.BigEndian(file.View.ReadUInt32(index_offset + 4));
+                index_offset += 8;
+                byte c;
+                List<byte> namebyte = new List<byte>();
+                while (true)
+                {
+                    c = file.View.ReadByte(index_offset);
+                    if (c == 0) break;
+                    namebyte.Add(c);
+                    index_offset++;
+                }
+                index_offset += 3;
+                //var sjis = System.Text.Encoding.GetEncoding("Shift-JIS");
+                var name = System.Text.Encoding.ASCII.GetString(namebyte.ToArray());
+                var entry = Create<Entry>(name);
+                entry.Offset = fstart;
+                entry.Size = flength;
+                if (!entry.CheckPlacement(file.MaxOffset))
+                    return null;
+                dir.Add(entry);
+            }
+            return new ArcFile(file, this, dir);
+        }
+    }
+}