Parser for one track working

1 files changed, 67 insertions, 0 deletions

diff --git a/project/Core/Src/Project/player.c b/project/Core/Src/Project/player.c
new file mode 100644
index 0000000..71531a8
--- /dev/null
+++ b/project/Core/Src/Project/player.c
@@ -0,0 +1,67 @@
+/*
+ * player.c
+ *
+ *  Created on: Nov 25, 2025
+ *      Author: sowgro
+ */
+
+#include "endian_converters.h"
+#include <stdint.h>
+#include "endian_converters.h"
+#include "hw8.h"
+
+#define NOTE_OFF_EVENT (0)
+#define NOTE_ON_EVENT (1)
+#define KEY_PRESSURE (2)
+
+typedef struct {
+	uint8_t ev_type;
+	uint32_t abs_time;
+	uint8_t key_number;
+	uint8_t value;
+} note_event_t;
+
+void parse_song(uint8_t *p_song) {
+	p_song += 4; // skip MTrk
+	uint32_t MTrk_len = convert_to_uint32(p_song);
+	p_song += 4;
+
+	note_event_t events[1/*track*/][1024/*event*/];
+	int curEvent = 0;
+	uint32_t prev_abs_time = 0;
+
+	for (uint8_t *p_end = p_song + MTrk_len; p_song != p_end; p_song++) {
+		note_event_t note;
+
+		parseDelay_result_t delay_result = parseDelay(p_song);
+		uint32_t abs_time = prev_abs_time + delay_result.value;
+		note.abs_time = abs_time;
+		prev_abs_time = abs_time;
+		p_song += delay_result.bytes_used;
+
+
+		if (*p_song >> 4 == 0b1000) {
+			note.ev_type = NOTE_OFF_EVENT;
+		} else if (*p_song >> 4 == 0b1001) {
+			note.ev_type = NOTE_ON_EVENT;
+		} else if (*p_song >> 4 == 0b1010) {
+			note.ev_type = KEY_PRESSURE;
+		} else {
+			continue;
+		}
+
+//		size_t channelNumber = *p_song && 0b00001111;
+		p_song++;
+
+		note.key_number = *p_song;
+		p_song++;
+
+		note.value = *p_song;
+		p_song++;
+
+		events[0][curEvent++] = note;
+	}
+	events[0][curEvent] = 0;
+
+	printf("done %p", events);
+}