#include <stdint.h>
#include <stdio.h>

#include "ch573/gpio.h"
#include "ch573/pwr.h"
#include "ch573/uart.h"
#include "clock.h"
#include "spi.h"
#include "string.h"
#include "system.h"
#include "ws2812b.h"

#define GPIO_PORT_A ch573_gpio__gpio_port_a
#define GPIO_PORT_B ch573_gpio__gpio_port_b
#define GPIO_PORT CH573_GPIO__GPIO_PORT_T_INTF

#define UART1 ch573_uart__uart1
#define UART CH573_UART__UART_T_INTF

#define PWR1 ch573_pwr__pwr_mgmt
#define PWR CH573_PWR__PWR_MGMT_T_INTF

uint32_t collatz(uint32_t n)
{
  uint32_t c = 0;

  while (n > 1) {
    if (n % 2 == 0) {
      n /= 2;
    } else {
      n = n * 3 + 1;
    }
    c++;
  }

  return c;
}

static void print_reg(uint32_t reg)
{
  // 0x40001008
  printf("register @0x%08x = 0x%08x\n", reg, *(uint32_t*)reg);
}

static void set_system_clock_6Mhz(void)
{
  print_reg(0x40001008);
  printf("Setting system clock to 6Mhz...\n");
  clock_cfg_t clk_cfg = {0};
  clk_cfg.sel = CLOCK_SELECTION_HSE;
  clk_cfg.pll_clock_divisor = 5;
  if (set_system_clock(&clk_cfg)) {
    printf("Failed to set system clock.\n");
  }
  print_reg(0x40001008);
  printf("Done\n");
}

static void set_system_clock_3Mhz(void)
{
  print_reg(0x40001008);
  printf("Setting system clock to 3Mhz...\n");
  clock_cfg_t clk_cfg = {0};
  clk_cfg.sel = CLOCK_SELECTION_HSE;
  clk_cfg.pll_clock_divisor = 10;
  if (set_system_clock(&clk_cfg)) {
    printf("Failed to set system clock.\n");
  }
  print_reg(0x40001008);
  printf("Done\n");
}

static void set_system_clock_60Mhz(void)
{
  print_reg(0x40001008);
  printf("Setting system clock to 60Mhz...\n");
  clock_cfg_t clk_cfg = {0};
  clk_cfg.sel = CLOCK_SELECTION_PLL;
  clk_cfg.pll_clock_divisor = 8;
  if (set_system_clock(&clk_cfg)) {
    printf("Failed to set system clock.\n");
  }
  print_reg(0x40001008);
  printf("Done\n");
}

static void set_system_clock_30Mhz(void)
{
  print_reg(0x40001008);
  printf("Setting system clock to 30Mhz...\n");
  clock_cfg_t clk_cfg = {0};
  clk_cfg.sel = CLOCK_SELECTION_PLL;
  clk_cfg.pll_clock_divisor = 16;
  if (set_system_clock(&clk_cfg)) {
    printf("Failed to set system clock.\n");
  }
  print_reg(0x40001008);
  printf("Done\n");
}

static void set_system_clock_32kHz()
{
  print_reg(0x40001008);
  printf("Setting system clock to 32kHz...\n");
  clock_cfg_t clk_cfg = {0};
  clk_cfg.sel = CLOCK_SELECTION_LSE;
  if (set_system_clock(&clk_cfg)) {
    printf("Failed to set system clock.\n");
  }
}

static void basic_delay()
{
  for (int i = 0; i < 100000; ++i) {
    asm volatile("");
  }
}

static void fast_delay()
{
  for (int i = 0; i < 1000; ++i) {
    asm volatile("");
  }
}

#define N_LEDS 100

extern int uart1_FILE_get(FILE* f);

/*
 * Main routine. This is called on_reset once everything else has been set up.
 */
int main(void)
{
  printf("Running SPI.\n");

  set_system_clock_60Mhz();

  printf("What is your name? ");
  char buf[1024];
  enable_spi();

  // char buf[1024];
  // memset(buf, 0xf0, sizeof(buf));
  // for (int i = 0; i < 50; ++ i) {
  //   buf[i] = 0xaa;
  //   buf[sizeof(buf) - i] = 0xaa;
  // }

  size_t n = sizeof(buf);
  struct ws2812b_buf ws_buf;
  make_wsb2812b(&ws_buf, buf, n);
  rgb_t color;
  color.color = 0;
  color.r = 0xff;
  color.g = 0x00;
  color.b = 0x00;
  uint8_t time = 0xff;

  // for (size_t i = 0; i < N_LEDS; ++i) {
  //   char* loc = buf + i * TOTAL_BYTES_PER_LED;
  //   printf(
  //       "Bytes: %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
  //       loc[0],
  //       loc[1],
  //       loc[2],
  //       loc[3],
  //       loc[4],
  //       loc[5],
  //       loc[6],
  //       loc[7],
  //       loc[8],
  //       loc[9],
  //       loc[10]);
  // }

  GPIO_PORT.dir.set(GPIO_PORT_B, DIR_OUT, 7);
  while (1) {
    ws_buf.cur = 0;
    for (int i = 0; i < N_LEDS; ++i) {
      color.r = time;
      color.g = 0;
      color.b = 0xff - time;
      write_rgb(&ws_buf, color);
    }
    time --;
    GPIO_PORT.out.set(GPIO_PORT_B, ON, 7);
    // printf("WS_BUF: %p, %zu\n", ws_buf.buf, ws_buf.cur);
    start_dma(&ws_buf);
    wait_for_dma();
    basic_delay();
  }

  return 0;
}