Add working pattern chaining prototype

3 files changed, 85 insertions, 15 deletions

diff --git a/src/drawing.c b/src/drawing.c
index dff5db2..4e793ea 100644
--- a/src/drawing.c
+++ b/src/drawing.c
@@ -1305,11 +1305,16 @@ draw_notif_bar() {
             *ptr++ = 'n';
             *ptr++ = ':';
             *ptr++ = ' ';
-            for (size_t i = 0; i < chain.len; i++) {
-                if (i != 0) {
+            bool first = true;
+            for (size_t i = 0; i < MAX_CHAIN; i++) {
+                if (chain.active[i] != 1) {
+                    continue;
+                }
+                if (!first) {
                     *ptr++ = '-';
                 }
                 *ptr++ = 'A' + chain.chain[i];
+                first = false;
             }
             *ptr++ = '\0';
             txt_drawf_small(msg, x0 + 2, y0 + 1, color);
@@ -1338,13 +1343,8 @@ draw_pattern_chain() {
         if (chain.active[i]) {
             txt_drawc('A' + chain.chain[i], x0 + 4, y0 + 3, color);
         }
+        if (chain.current == i && chain.len != 0) {
+            draw_line(x0 + 5, y1 - 2, x1 - 5, y1 - 2, COL_ACC_0);
+        }
     }
-    // draw_rect(
-    //         PARAMS_START_X,
-    //         PARAMS_START_Y + 6,
-    //         PARAMS_START_X + PARAMS_W,
-    //         PARAMS_START_Y + PARAMS_H - 6, COL_FG);
-    // txt_drawf_small("Current pattern: %s", PARAMS_START_X + 3, PARAMS_START_Y + 8, COL_FG, "A");
-    // txt_drawf_small("Next pattern: %s", PARAMS_START_X + 3, PARAMS_START_Y + 8 * 2, COL_FG, "A");
-    // txt_drawf_small("Chain: %s", PARAMS_START_X + 3, PARAMS_START_Y + 8 * 3, COL_FG, "A - B - B - A - B");
 }
diff --git a/src/globals.c b/src/globals.c
index 3a70005..1efa90c 100644
--- a/src/globals.c
+++ b/src/globals.c
@@ -144,8 +144,10 @@ typedef struct Chain {
     u8 chain[MAX_CHAIN];
     u8 active[MAX_CHAIN];
     u8 len;
-    u8 loop;
     u8 current;
+    u8 playing;
 } Chain;
 
+// DEBUG:...
+// static Chain chain = {.chain = {0, 1, 2, 3, 4, 5, 6}, .active = { 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1,1, 1,1,1,1}, .len = 14};
 static Chain chain = {0};
diff --git a/src/sequencer.c b/src/sequencer.c
index 44ff90e..8d79c65 100644
--- a/src/sequencer.c
+++ b/src/sequencer.c
@@ -47,6 +47,30 @@ gate_on(void) {
     TIMER_CTRL_3 = TIMER_CTRL_IRQ | TIMER_CTRL_ENABLE | TIMER_CTRL_FREQ_3;
 }
 
+u8
+find_next_pattern(void) {
+    u8 idx = (chain.current + 1) % 16;
+    for (size_t i = 0; i < MAX_CHAIN; i++) {
+        if (chain.active[idx] == 1) {
+            break;
+        }
+        idx = (idx + 1) % 16;
+    }
+    return idx;
+}
+
+u8
+find_prev_pattern(void) {
+    u8 idx = chain.current == 0 ? 15 : (chain.current - 1);
+    for (size_t i = 0; i < MAX_CHAIN; i++) {
+        if (chain.active[idx] == 1) {
+            break;
+        }
+        idx = chain.current == 0 ? 15 : (chain.current - 1);
+    }
+    return idx;
+}
+
 void
 play_step(void) {
     Pattern *pat = &patterns[current_pattern];
@@ -54,6 +78,18 @@ play_step(void) {
         current_pattern = next_pattern;
         redraw_pattern_buttons = true;
         update_bpm = true;
+    } else if (chain.len != 0 && step_counter == 15) {
+        redraw_pattern_buttons = true;
+        update_bpm = true;
+        if (!chain.playing) {
+            next_pattern = chain.chain[chain.current];
+            current_pattern = next_pattern;
+        } else {
+            chain.current = find_next_pattern();
+            next_pattern = chain.chain[chain.current];
+            current_pattern = next_pattern;
+        }
+        chain.playing = true;
     }
     if (pat->ch1.active) {
         TriggerNote *trig = &pat->ch1.notes[step_counter];
@@ -316,6 +352,9 @@ stop_sound(void) {
 void
 stop_playing(void) {
     step_counter = 0;
+    chain.current = 15;
+    chain.current = find_next_pattern();
+    chain.playing = false;
     stop_sound();
 }
 
@@ -323,6 +362,15 @@ void
 toggle_playing(void) {
     play_status ^= 1;
     step_counter = 0;
+    chain.current = 15;
+    chain.current = find_next_pattern();
+    chain.playing = false;
+    if (current_pattern == next_pattern && chain.len > 0) {
+        chain.playing = true;
+        next_pattern = chain.chain[chain.current];
+        current_pattern = next_pattern;
+    }
+    redraw_pattern_buttons = true;
     SOUND_SQUARE1_CTRL = 0;
     SOUND_SQUARE2_CTRL = 0;
     SOUND_WAVE_CTRL = 0;
@@ -351,6 +399,12 @@ pause_playing(void) {
     SOUND_SQUARE2_CTRL = 0;
     SOUND_WAVE_CTRL = 0;
     SOUND_NOISE_CTRL = 0;
+    chain.playing = false;
+    if (current_pattern == next_pattern && chain.len > 0) {
+        chain.playing = true;
+        next_pattern = chain.chain[chain.current];
+        current_pattern = next_pattern;
+    }
     redraw_play_pause = true;
     if (settings.sync == SYNC_IN_LINK) {
         return;
@@ -530,23 +584,37 @@ handle_pattern_selection(void) {
             }
         }
         if (slot > -1) {
+            if (chain.len == 0) {
+                chain.current = slot;
+            }
             chain.chain[slot] = pattern_selection_loc;
             chain.active[slot] = 1;
-            chain.len++; // TODO: remove
+            chain.len++;
         }
     }
     if (key_tap(KEY_L)) {
         // Find last active slot.
         s16 slot = -1;
+        bool update_current = false;
         for (size_t i = 0; i < 16; i++) {
-            if (chain.active[15 - i] == 1) {
-                slot = 15 - i;
+            size_t idx = 15 - i;
+            if (chain.active[idx] == 1) {
+                // If the pattern is currently playing it can't be removed.
+                if (play_status && idx == chain.current) {
+                    continue;
+                } else if (idx == chain.current) {
+                    update_current = true;
+                }
+                slot = idx;
                 break;
             }
         }
         if (slot > -1) {
             chain.active[slot] = 0;
-            chain.len--; // TODO: remove
+            chain.len--;
+            if (update_current) {
+                chain.current = find_prev_pattern();
+            }
         }
     }
 }