From 7a4c3af4e532fb5ce9eb6c049659d1f1edc23c1e Mon Sep 17 00:00:00 2001
From: Jon Heard <jon.heard.tutor@gmail.com>
Date: Thu, 31 Aug 2023 04:11:59 -0400
Subject: [PATCH 1/2] - Events added to react to rowChange, patternChange,
 songEnd and effect

---
 js/ft2.js    | 11 ++++++++++-
 js/player.js | 10 +++++++---
 js/pt.js     | 19 +++++++++++++++----
 js/st3.js    | 11 ++++++++++-
 4 files changed, 42 insertions(+), 9 deletions(-)

diff --git a/js/ft2.js b/js/ft2.js
index cd4d57a..e127c53 100644
--- a/js/ft2.js
+++ b/js/ft2.js
@@ -15,8 +15,10 @@
   Greets to Guru, Alfred and CCR for their work figuring out the .xm format. :)
 */
 
-function Fasttracker()
+function Fasttracker(songEventListener)
 {
+  this.songEventListener = songEventListener;
+
   var i, t;
 
   this.clearsong();
@@ -587,6 +589,7 @@ Fasttracker.prototype.advance = function(mod) {
         mod.row++; mod.tick=0; mod.flags|=2;
       }
     }
+    this.songEventListener.onSongRowChange?.();
   }
   
   // step to new pattern?
@@ -594,14 +597,17 @@ Fasttracker.prototype.advance = function(mod) {
     mod.position++;
     mod.row=0;
     mod.flags|=4;
+    this.songEventListener.onSongPatternChange?.();
   }
   
   // end of song?
   if (mod.position>=mod.songlen) {
     if (mod.repeat) {
       mod.position=0;
+      this.songEventListener.onSongEnd?.(true);
     } else {
       this.endofsong=true;
+      this.songEventListener.onSongEnd?.(false);
     }
     return;
   }
@@ -742,6 +748,9 @@ Fasttracker.prototype.process_tick = function(mod) {
       if (!mod.tick) {
         // process only on tick 0
         mod.effects_t0[mod.channel[ch].command](mod, ch);
+        if (this.songEventListener.onSongEffect && (mod.channel[ch].command > 0 || mod.channel[ch].data > 0)) {
+          this.songEventListener.onSongEffect(ch, mod.channel[ch].command, mod.channel[ch].data);
+        }
       } else {
         mod.effects_t1[mod.channel[ch].command](mod, ch);
       }
diff --git a/js/player.js b/js/player.js
index 4c9968d..4b9720d 100644
--- a/js/player.js
+++ b/js/player.js
@@ -38,6 +38,10 @@ function Modplayer()
   this.onReady=function(){};
   this.onPlay=function(){};
   this.onStop=function(){};
+  this.onSongPatternChange = null;
+  this.onSongEnd = null; // params = isRepeating
+  this.onSongRowChange = null;
+  this.onSongEffect = null; // params = channel, command, command-data
 
   this.buffer=0;
   this.mixerNode=0;
@@ -80,13 +84,13 @@ Modplayer.prototype.load = function(url)
 
   switch (ext) {
     case 'mod':
-      this.player=new Protracker();
+      this.player=new Protracker(this);
       break;
     case 's3m':
-      this.player=new Screamtracker();
+      this.player=new Screamtracker(this);
       break;
     case 'xm':
-      this.player=new Fasttracker();
+      this.player=new Fasttracker(this);
       break;
   }
 
diff --git a/js/pt.js b/js/pt.js
index feaf580..12125ce 100644
--- a/js/pt.js
+++ b/js/pt.js
@@ -12,8 +12,10 @@
 */
 
 // constructor for protracker player object
-function Protracker()
+function Protracker(songEventListener)
 {
+  this.songEventListener = songEventListener;
+
   var i, t;
 
   this.clearsong();
@@ -320,7 +322,6 @@ Protracker.prototype.advance = function(mod) {
   // advance player
   if (mod.offset>spd) { mod.tick++; mod.offset=0; mod.flags|=1; }
   if (mod.tick>=mod.speed) {
-
     if (mod.patterndelay) { // delay pattern
       if (mod.tick < ((mod.patternwait+1)*mod.speed)) {
         mod.patternwait++;
@@ -350,14 +351,22 @@ Protracker.prototype.advance = function(mod) {
         mod.row++; mod.tick=0; mod.flags|=2;
       }
     }
+    this.songEventListener.onSongRowChange?.();
+  }
+  if (mod.row>=64) {
+    mod.position++;
+    mod.row=0;
+    mod.flags|=4;
+    this.songEventListener.onSongPatternChange?.();
   }
-  if (mod.row>=64) { mod.position++; mod.row=0; mod.flags|=4; }
   if (mod.position>=mod.songlen) {
     if (mod.repeat) {
       mod.position=0;
+      this.songEventListener.onSongEnd?.(true);
     } else {
       this.endofsong=true;
       //mod.stop();
+      this.songEventListener.onSongEnd?.(false);
     }
     return;
   }
@@ -417,12 +426,14 @@ Protracker.prototype.mix = function(mod, bufs, buflen) {
 
         // kill empty samples
         if (!mod.sample[mod.channel[ch].sample].length) mod.channel[ch].noteon=0;
-
         // effects
         if (mod.flags&1) {
           if (!mod.tick) {
             // process only on tick 0
             mod.effects_t0[mod.channel[ch].command](mod, ch);
+            if (this.songEventListener.onSongEffect && (mod.channel[ch].command > 0 || mod.channel[ch].data > 0)) {
+              this.songEventListener.onSongEffect(ch, mod.channel[ch].command, mod.channel[ch].data);
+            }
           } else {
             mod.effects_t1[mod.channel[ch].command](mod, ch);
           }
diff --git a/js/st3.js b/js/st3.js
index ed636f8..2ecfc31 100644
--- a/js/st3.js
+++ b/js/st3.js
@@ -11,8 +11,10 @@
     command data memory?
 */
 
-function Screamtracker()
+function Screamtracker(songEventListener)
 {
+  this.songEventListener = songEventListener;
+
   var i, t;
 
   this.clearsong();
@@ -440,6 +442,7 @@ Screamtracker.prototype.advance = function(mod) {
         mod.row++; mod.tick=0; mod.flags|=2;
       }
     }
+    this.songEventListener.onSongRowChange?.();
   }
 
   // step to new pattern?
@@ -448,14 +451,17 @@ Screamtracker.prototype.advance = function(mod) {
     mod.row=0;
     mod.flags|=4;
     while (mod.patterntable[mod.position]==254) mod.position++; // skip markers
+    this.songEventListener.onSongPatternChange?.();
   }
 
   // end of song?
   if (mod.position>=mod.songlen || mod.patterntable[mod.position]==255) {
     if (mod.repeat) {
       mod.position=0;
+      this.songEventListener.onSongEnd?.(true);
     } else {
       this.endofsong=true;
+      this.songEventListener.onSongEnd?.(false);
     }
     return;
   }
@@ -547,6 +553,9 @@ Screamtracker.prototype.process_tick = function(mod) {
       if (!mod.tick) {
         // process only on tick 0 effects
         mod.effects_t0[mod.channel[ch].command](mod, ch);
+        if (this.songEventListener.onSongEffect && (mod.channel[ch].command > 0 || mod.channel[ch].data > 0)) {
+          this.songEventListener.onSongEffect(ch, mod.channel[ch].command, mod.channel[ch].data);
+        }
       } else {
         mod.effects_t1[mod.channel[ch].command](mod, ch);
       }

From 5348135b6b655d633c4b1bfcb2518542a689bf4c Mon Sep 17 00:00:00 2001
From: Jon Heard <jon.heard.tutor@gmail.com>
Date: Thu, 31 Aug 2023 04:36:38 -0400
Subject: [PATCH 2/2] Undid some unnecessary newline removal from prior commit.

---
 js/pt.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/js/pt.js b/js/pt.js
index 12125ce..ada0e18 100644
--- a/js/pt.js
+++ b/js/pt.js
@@ -322,6 +322,7 @@ Protracker.prototype.advance = function(mod) {
   // advance player
   if (mod.offset>spd) { mod.tick++; mod.offset=0; mod.flags|=1; }
   if (mod.tick>=mod.speed) {
+
     if (mod.patterndelay) { // delay pattern
       if (mod.tick < ((mod.patternwait+1)*mod.speed)) {
         mod.patternwait++;
@@ -426,6 +427,7 @@ Protracker.prototype.mix = function(mod, bufs, buflen) {
 
         // kill empty samples
         if (!mod.sample[mod.channel[ch].sample].length) mod.channel[ch].noteon=0;
+
         // effects
         if (mod.flags&1) {
           if (!mod.tick) {