#include <stdint.h>
#include "system.h"
#include "display.h"
#include "systick.h"
#include "button.h"
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "ui.h"
#include "timer.h"
#include "led.h"
#include "drone.h"
#include "drums.h"
#include "pot.h"

static struct drone_slot drone_pattern[MAX_PATTERN_LEN] = { 
    { 28, 10 }, { 28, 20}, {36,20}, {40,20},
    { 40, 10 }, { 40, 10}, {36, 10}, {32,10}
};

void drone_beat(int pattern_pos)
{
    struct drone_slot *key = &drone_pattern[pattern_pos];
    static int test_lfo_step = 0;
    static int test_lfo = 0;
    int lfo_depth = 80;
    int lfo_rate = 7;
    int lfo_step = 2;
    int tgt_env;
    pot_set(0, 99);

    if ((pattern_pos % lfo_step) == 0) {
        if (test_lfo_step == 0) {
            test_lfo+=lfo_rate;
            if (test_lfo > lfo_depth)
                test_lfo_step = 1;
        } else {
            test_lfo-=lfo_rate;
            if (test_lfo < (0 - lfo_depth))
                test_lfo_step = 0;
        }
    }


    tgt_env = key->env + test_lfo;
    if (tgt_env < 0) {
        tgt_env = 0;
        test_lfo_step = 0;
    }
    if (tgt_env > 99) {
        tgt_env = 99;
        test_lfo_step = 1;
    }

    pot_set(0, key->pitch);
    pot_set(1, tgt_env);
}