From d67c9862aee1e690febc2c946ff7a267d90c4bec Mon Sep 17 00:00:00 2001
From: GenericHeroGuy <genericheroguy@noreply.codeberg.org>
Date: Fri, 24 Jan 2025 17:17:47 +0100
Subject: [PATCH] Add compatmode flag

---
 src/d_netcmd.c |  2 ++
 src/w_wad.c    | 40 ++++++++++++++++++++++++++++++++++++++++
 src/w_wad.h    |  1 +
 3 files changed, 43 insertions(+)

diff --git a/src/d_netcmd.c b/src/d_netcmd.c
index fde1a4e27..2a488a17c 100644
--- a/src/d_netcmd.c
+++ b/src/d_netcmd.c
@@ -4634,6 +4634,8 @@ static void Command_ListWADS_f(void)
 			CONS_Printf("\x82 * %.2d\x80: %s\n", i, tempname);
 		else if (!wadfiles[i]->important)
 			CONS_Printf("\x86   %.2d: %s\n", i, tempname);
+		else if (wadfiles[i]->compatmode)
+			CONS_Printf("\x8a   %.2d: %s\n", i, tempname);
 		else
 			CONS_Printf("   %.2d: %s\n", i, tempname);
 	}
diff --git a/src/w_wad.c b/src/w_wad.c
index afc6c2caf..e9f346746 100644
--- a/src/w_wad.c
+++ b/src/w_wad.c
@@ -291,6 +291,33 @@ static inline void W_LoadDehackedLumps(UINT16 wadnum, boolean mainfile)
 #endif
 }
 
+static inline boolean CheckCompatFilename(char *filename)
+{
+	// check for a K prefix
+	char *basename = strrchr(filename, *PATHSEP);
+	return toupper(basename ? basename[1] : filename[0]) == 'K';
+}
+
+// try to figure out if a PK3 file needs compatmode enabled (palette remap)
+static inline boolean CheckCompatZip(UINT16 wadnum)
+{
+	if (CheckCompatFilename(wadfiles[wadnum]->filename))
+		return true;
+
+	// assume RR/2.2 for PK3s so basegame assets work
+	return false;
+}
+
+// ditto, but for WADs
+static inline boolean CheckCompatWad(UINT16 wadnum)
+{
+	if (CheckCompatFilename(wadfiles[wadnum]->filename))
+		return true;
+
+	// assume Kart/2.1 for WADs so basegame assets work
+	return true;
+}
+
 /** Compute MD5 message digest for bytes read from STREAM of this filname.
   *
   * The resulting message digest number will be written into the 16 bytes
@@ -872,6 +899,19 @@ UINT16 W_InitFile(const char *filename, boolean mainfile, boolean startup)
 		break;
 	}
 
+	// check if compatmode is needed
+	switch (wadfile->type)
+	{
+	case RET_WAD:
+		wadfile->compatmode = CheckCompatWad(numwadfiles - 1);
+		break;
+	case RET_PK3:
+		wadfile->compatmode = CheckCompatZip(numwadfiles - 1);
+		break;
+	default:
+		break;
+	}
+
 	if (refreshdirmenu & REFRESHDIR_GAMEDATA)
 		G_LoadGameData();
 	DEH_UpdateMaxFreeslots();
diff --git a/src/w_wad.h b/src/w_wad.h
index 43aa1b228..27b7174ac 100644
--- a/src/w_wad.h
+++ b/src/w_wad.h
@@ -128,6 +128,7 @@ struct wadfile_t
 	UINT8 md5sum[16];
 
 	boolean important; // also network - !W_VerifyNMUSlumps
+	boolean compatmode; // TODO: network this too!
 };
 
 #define WADFILENUM(lumpnum) (UINT16)((lumpnum)>>16) // wad flumpnum>>16) // wad file number in upper word