From e103468b8695a61b84ec0079cbbad1c4127652ba Mon Sep 17 00:00:00 2001
From: Gwilym Inzani <email@gwilym.dev>
Date: Wed, 1 Nov 2023 13:28:01 +0000
Subject: [PATCH] Vaguely get the correct beat and the patterns correct

---
 tracker/agb-midi-core/src/lib.rs       | 23 +++++++++++++++++++----
 tracker/agb-tracker-interop/src/lib.rs |  4 ++--
 2 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/tracker/agb-midi-core/src/lib.rs b/tracker/agb-midi-core/src/lib.rs
index 4fe8a2f5..6aefa9e8 100644
--- a/tracker/agb-midi-core/src/lib.rs
+++ b/tracker/agb-midi-core/src/lib.rs
@@ -190,6 +190,13 @@ pub fn parse_midi(midi_info: &MidiInfo) -> TokenStream {
         }
     }
 
+    patterns.retain(|pattern| {
+        !pattern.iter().all(|pattern_slot| {
+            matches!(pattern_slot.effect1, PatternEffect::None)
+                && matches!(pattern_slot.effect2, PatternEffect::None)
+        })
+    });
+
     for pattern in &mut patterns {
         pattern.resize_with(current_ticks as usize, || PatternSlot {
             speed: 0.into(),
@@ -211,20 +218,28 @@ pub fn parse_midi(midi_info: &MidiInfo) -> TokenStream {
         })
         .collect();
 
-    let pattern = patterns.into_iter().flatten().collect::<Vec<_>>();
+    let resulting_num_channels = patterns.len();
+    let mut pattern = Vec::with_capacity(current_ticks as usize * resulting_num_channels);
+    for i in 0..current_ticks {
+        for pattern_slots in &patterns {
+            pattern.push(pattern_slots[i as usize].clone());
+        }
+    }
 
     let track = Track {
         samples: &samples,
         envelopes: &[],
         pattern_data: &pattern,
         patterns: &[Pattern {
-            length: pattern.len() / channel_data.len(),
+            length: pattern.len() / resulting_num_channels,
             start_position: 0,
         }],
         patterns_to_play: &[0],
-        num_channels: channel_data.len(),
+        num_channels: resulting_num_channels,
         frames_per_tick: Num::from_f64(
-            initial_microseconds_per_beat.expect("No tempo was ever sent") as f64 / 16742.706298828, // microseconds per frame
+            initial_microseconds_per_beat.expect("No tempo was ever sent") as f64
+                / 16742.706298828 // microseconds per frame
+                / ticks_per_beat as f64,
         ),
         ticks_per_step: 1,
         repeat: 0,
diff --git a/tracker/agb-tracker-interop/src/lib.rs b/tracker/agb-tracker-interop/src/lib.rs
index 7261d683..1a2c05f3 100644
--- a/tracker/agb-tracker-interop/src/lib.rs
+++ b/tracker/agb-tracker-interop/src/lib.rs
@@ -32,7 +32,7 @@ pub struct Pattern {
     pub start_position: usize,
 }
 
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub struct PatternSlot {
     pub speed: Num<u16, 8>,
     pub sample: u16,
@@ -48,7 +48,7 @@ pub struct Envelope<'a> {
     pub loop_end: Option<usize>,
 }
 
-#[derive(Debug, Default)]
+#[derive(Debug, Default, Clone)]
 pub enum PatternEffect {
     /// Don't play an effect
     #[default]