From db10092d88022ee07d540a547a4ad890fc22e576 Mon Sep 17 00:00:00 2001
From: tildearrow <me@tildearrow.org>
Date: Sun, 23 Jun 2024 01:31:03 -0500
Subject: [PATCH] IT import: pattern data

---
 src/engine/fileOps/it.cpp | 214 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 214 insertions(+)

diff --git a/src/engine/fileOps/it.cpp b/src/engine/fileOps/it.cpp
index 78b29a571..e8d64f046 100644
--- a/src/engine/fileOps/it.cpp
+++ b/src/engine/fileOps/it.cpp
@@ -23,6 +23,16 @@ bool DivEngine::loadIT(unsigned char* file, size_t len) {
   struct InvalidHeaderException {};
   bool success=false;
   char magic[4];
+
+  unsigned char chanPan[64];
+  unsigned char chanVol[64];
+
+  unsigned char orders[256];
+
+  unsigned int insPtr[256];
+  unsigned int samplePtr[256];
+  unsigned int patPtr[256];
+  
   SafeReader reader=SafeReader(file,len);
   warnings="";
 
@@ -36,6 +46,16 @@ bool DivEngine::loadIT(unsigned char* file, size_t len) {
     ds.ignoreJumpAtEnd=false;
     ds.pitchSlideSpeed=12;
 
+    ds.system[0]=DIV_SYSTEM_DUMMY;
+    ds.system[1]=DIV_SYSTEM_DUMMY;
+    ds.system[2]=DIV_SYSTEM_DUMMY;
+    ds.system[3]=DIV_SYSTEM_DUMMY;
+    ds.system[4]=DIV_SYSTEM_DUMMY;
+    ds.system[5]=DIV_SYSTEM_DUMMY;
+    ds.system[6]=DIV_SYSTEM_DUMMY;
+    ds.system[7]=DIV_SYSTEM_DUMMY;
+    ds.systemLen=8;
+
     logV("Impulse Tracker module");
 
     // load here
@@ -54,6 +74,200 @@ bool DivEngine::loadIT(unsigned char* file, size_t len) {
 
     ds.name=reader.readString(26);
 
+    unsigned char hilight1=reader.readC();
+    unsigned char hilight2=reader.readC();
+    logV("highlights: %d %d",hilight1,hilight2);
+
+    unsigned short ordersLen=reader.readS();
+    ds.insLen=reader.readS();
+    ds.sampleLen=reader.readS();
+    unsigned short patCount=reader.readS();
+    unsigned short usedTracker=reader.readS();
+    unsigned short compatTracker=reader.readS();
+    unsigned short flags=reader.readS();
+    unsigned short special=reader.readS();
+
+    unsigned char globalVol=reader.readC();
+    unsigned char masterVol=reader.readC();
+    unsigned char initSpeed=reader.readC();
+    unsigned char initTempo=reader.readC();
+    unsigned char panSep=reader.readC();
+    reader.readC(); // PWD - unused
+
+    logV("orders len: %d",ordersLen);
+    logV("pattern count: %d",patCount);
+    logV("used tracker: %x",usedTracker);
+    logV("compatible with: %x",compatTracker);
+    logV("flags: %x",flags);
+    logV("special: %x",special);
+
+    logV("global vol: %d",globalVol);
+    logV("master vol: %d",masterVol);
+    logV("speed: %d",initSpeed);
+    logV("tempo: %d",initTempo);
+    logV("pan sep: %d",panSep);
+
+    unsigned short commentLen=reader.readS();
+    unsigned int commentPtr=reader.readI();
+
+    logV("comment len: %d",commentLen);
+    logV("comment ptr: %x",commentPtr);
+
+    reader.readI(); // reserved
+
+    reader.read(chanPan,64);
+    reader.read(chanVol,64);
+
+    reader.read(orders,ordersLen);
+
+    for (int i=0; i<ordersLen; i++) {
+      for (int j=0; j<DIV_MAX_CHANS; j++) {
+        ds.subsong[0]->orders.ord[j][i]=orders[i];
+      }
+    }
+    ds.subsong[0]->ordersLen=ordersLen;
+
+    for (int i=0; i<ds.insLen; i++) {
+      insPtr[i]=reader.readI();
+    }
+
+    for (int i=0; i<ds.sampleLen; i++) {
+      samplePtr[i]=reader.readI();
+    }
+
+    for (int i=0; i<patCount; i++) {
+      patPtr[i]=reader.readI();
+    }
+
+    // read instruments
+    for (int i=0; i<ds.insLen; i++) {
+      DivInstrument* ins=new DivInstrument;
+
+      ds.ins.push_back(ins);
+    }
+
+    // read samples
+    for (int i=0; i<ds.sampleLen; i++) {
+      DivSample* s=new DivSample;
+
+      ds.sample.push_back(s);
+    }
+
+    // read patterns
+    for (int i=0; i<patCount; i++) {
+      unsigned char mask[64];
+      unsigned char note[64];
+      unsigned char ins[64];
+      unsigned char vol[64];
+      unsigned char effect[64];
+      unsigned char effectVal[64];
+      int curRow=0;
+
+      memset(mask,0,64);
+      memset(note,0,64);
+      memset(ins,0,64);
+      memset(vol,0,64);
+      memset(effect,0,64);
+      memset(effectVal,0,64);
+
+      logV("reading pattern %d...",i);
+      if (!reader.seek(patPtr[i],SEEK_SET)) {
+        logE("premature end of file!");
+        lastError="incomplete file";
+        delete[] file;
+        return false;
+      }
+
+      unsigned int dataLen=(unsigned short)reader.readS();
+      unsigned short patRows=reader.readS();
+
+      reader.readI(); // x
+
+      dataLen+=reader.tell();
+
+      // read pattern data
+      while (reader.tell()<dataLen) {
+        unsigned char chan=reader.readC();
+        bool hasNote=false;
+        bool hasIns=false;
+        bool hasVol=false;
+        bool hasEffect=false;
+
+        if (chan==0) {
+          curRow++;
+          if (curRow>=patRows) break;
+          continue;
+        }
+
+        if (chan&128) {
+          mask[chan&63]=reader.readC();
+        }
+        chan&=63;
+
+        if (mask[chan]&1) {
+          note[chan]=reader.readC();
+          hasNote=true;
+        }
+        if (mask[chan]&2) {
+          ins[chan]=reader.readC();
+          hasIns=true;
+        }
+        if (mask[chan]&4) {
+          vol[chan]=reader.readC();
+          hasVol=true;
+        }
+        if (mask[chan]&8) {
+          effect[chan]=reader.readC();
+          effectVal[chan]=reader.readC();
+          hasEffect=true;
+        }
+        if (mask[chan]&16) {
+          hasNote=true;
+        }
+        if (mask[chan]&32) {
+          hasIns=true;
+        }
+        if (mask[chan]&64) {
+          hasVol=true;
+        }
+        if (mask[chan]&128) {
+          hasEffect=true;
+        }
+
+        DivPattern* p=ds.subsong[0]->pat[chan].getPattern(i,true);
+
+        if (hasNote) {
+          if (note[chan]==255) { // note off
+            p->data[curRow][0]=100;
+            p->data[curRow][1]=0;
+          } else if (note[chan]==254) { // note release
+            p->data[curRow][0]=101;
+            p->data[curRow][1]=0;
+          } else if (note[chan]<120) {
+            p->data[curRow][0]=note[chan]%12;
+            p->data[curRow][1]=note[chan]/12;
+            if (p->data[curRow][0]==0) {
+              p->data[curRow][0]=12;
+              p->data[curRow][1]--;
+            }
+          }
+        }
+        if (hasIns) {
+          p->data[curRow][2]=ins[chan]-1;
+        }
+        if (hasVol) {
+          p->data[curRow][3]=vol[chan];
+        }
+        if (hasEffect) {
+          //p->data[curRow][4]=effect[chan];
+          //p->data[curRow][5]=effectVal[chan];
+        }
+      }
+    }
+
+    logV("DAMN IT: %x",insPtr[0]);
+    logV("DAMN IT: %x",samplePtr[0]);
+
     if (active) quitDispatch();
     BUSY_BEGIN_SOFT;
     saveLock.lock();