#include "arch.h"
#include "arch/arm/cortex-m4/mpu.h"
#include "arch/stm32l4xxx/peripherals/clock.h"
#include "arch/stm32l4xxx/peripherals/dma.h"
#include "arch/stm32l4xxx/peripherals/rcc.h"
#include "arch/stm32l4xxx/peripherals/irq.h"
#include "arch/stm32l4xxx/peripherals/spi.h"
#include "arch/stm32l4xxx/peripherals/system.h"
#include "kern/gpio/gpio_manager.h"
#include "kern/dma/dma_manager.h"
#include "kern/init.h"
#include "kern/log.h"
#include "kern/mem.h"
#include "kern/mpu/mpu_manager.h"
#include "kern/panic.h"
#include "kern/delay.h"
#include "kern/priv.h"
#include "kern/gpio/sysled.h"
#include "arch/stm32l4xxx/peripherals/clock.h"
#include "user/syscall.h"
#include "drv/ws2812B/ws2812b.h"


gpio_reserved_pin_t sysl;
int syslon;
int n;
uint16_t my_short;
extern uint16_t dma_inuse;

void on_spi1()
{
  SPI1.d_r = ~my_short;
  if (n++ == 10000) {
    if (syslon) {
      set_gpio_pin_low(sysl);
    } else {
      set_gpio_pin_high(sysl);
    }

    syslon = !syslon;
    n = 0;
  }
}

inline void spi_write_byte(uint8_t byte)
{
  // volatile uint32_t read;

  //delay(5);
  //while (regget(SPI1.s_r, spi_rxne)) {
  //  read = SPI1.d_r;
  //}
  //delay(5);

  //delay(5);
  while (regget(SPI1.s_r, spi_ftlvl) > SPI_FIFO_STATUS_HALF);
  SPI1.d_r = (byte << 8) | byte;
}

void on_hard_fault()
{
  panic("Hard fault encountered!\n");
}

void on_systick() /* Overrides weak-symbol on_systick. */
{
  // klogf("systick\n");
  if (my_short == 0) my_short = 0xffff;
  my_short >>=1;
}

void configure_mpu()
{
  configure_flash_region((void*)0x08000000, REGION_SIZE_256Kb, NOT_PRIVILEGED);
  configure_ram_region((void*)SRAM1_BASE, REGION_SIZE_64Kb, NOT_PRIVILEGED);
  configure_ram_region((void*)SRAM2_BASE, REGION_SIZE_16Kb, NOT_PRIVILEGED);
  configure_peripheral_region((void*)0x40000000, REGION_SIZE_512Mb, PRIVILEGED);
  mpu_set_enabled(1);
}

static void dma_callback(void* arg)
{
  klogf("Dma callback\n");
  dma_channel_t* chan = arg;

  release_dma_channel(*chan);
  dma_channel_interrupt_enable(*chan, 0);

  regset(SPI1.c_r1, spi_spe, 0);

  DMA2.ifc_r |= 0xffffffff;
  DMA1.ifc_r |= 0xffffffff;
  regset(DMA2.channel_config[3].cc_r, dma_cc_en, 0);
}

#ifdef ARCH_STM32L4

/* Main function. This gets executed from the interrupt vector defined above. */
int main()
{
  int ec = 0;

  size_t size = 20;
  rgb_t arr[] = {
    {0x00, 0x00, 0xff},
    {0x00, 0xff, 0x00},
    {0xff, 0x00, 0x00},

    {0xff, 0x80, 0x80},
    {0x80, 0xff, 0x80},
    {0x80, 0x80, 0xff},

    {0xff, 0xff, 0xff},
    {0xff, 0xff, 0xff},
    {0xff, 0xff, 0xff},

    {0xff, 0xff, 0xff},
    {0xff, 0xff, 0xff},
    {0xff, 0xff, 0xff},

    {0xff, 0xff, 0xff},
    {0xff, 0xff, 0xff},
    {0xff, 0xff, 0xff},

    {0xff, 0xff, 0xff},
    {0xff, 0xff, 0xff},
    {0xff, 0xff, 0xff},

    {0xff, 0xff, 0xff},
    {0xff, 0xff, 0xff},
    {0xff, 0xff, 0xff},

    {0xff, 0xff, 0xff},
    {0xff, 0xff, 0xff},
    {0xff, 0xff, 0xff},

    {0xff, 0xff, 0xff},
    {0xff, 0xff, 0xff},
    {0xff, 0xff, 0xff},

    {0xff, 0xff, 0xff},
    {0xff, 0xff, 0xff},
    {0xff, 0xff, 0xff},
  };
  uint8_t* dataptr = ws2812b_compile_rgb(arr, size);

  klogf("Heap start: %p\n", &HEAP_START);
  klogf("Heap end: %p\n", &HEAP_STOP);
  klogf("Dataptr start: %p\n", dataptr);
  klogf("Dataptr end: %p\n", (dataptr + size));

  dma_opts_t opts = DEFAULT_DMA_OPTS;
  opts.transfer_complete_interrupt_enable = 1;
  opts.circular_mode = 0;
  dma_mem2p_channel_t dma_chan =
    select_dma_channel_mem2p(DMA2_PERIPH_SPI1_TX, &opts, &ec);
  dma_chan_set_callback(dma_chan.c_, dma_callback, &dma_chan);

  if (ec) {
    panic("Unable to allocate dma channel: %d\n", ec);
  }

  my_short = 0xff;
  klogf("This is weird.\n");
  // configure_mpu();
  sysl = get_sysled();

  // gpio_enable_alternate_function(
  //     GPIO_ALTERNATE_FUNCTION_SPI1_MISO, GPIO_PIN_PA6, &ec);
  // if (ec) {
  //   klogf("Unable to set pin PA6 (ec=%d)\n", ec);
  // }
  gpio_enable_alternate_function(
      GPIO_ALTERNATE_FUNCTION_SPI1_MOSI, GPIO_PIN_PA7, &ec);
  if (ec) {
    klogf("Unable to set pin PA7 (ec=%d)\n", ec);
  }
  gpio_enable_alternate_function(
      GPIO_ALTERNATE_FUNCTION_SPI1_NSS, GPIO_PIN_PA4, &ec);
  if (ec) {
    klogf("Unable to set pin PA4 (ec=%d)\n", ec);
  }
  gpio_enable_alternate_function(
      GPIO_ALTERNATE_FUNCTION_SPI1_SCK, GPIO_PIN_PA5, &ec);
  if (ec) {
    klogf("Unable to set pin PA5 (ec=%d)\n", ec);
  }

  /* Set the countdown to start from 10,000,0000. */
  SCB.strv_r = 1000000;

  /* Enable interrupts. */
  regset(SCB.stcs_r, scb_tickint, 1);

  /* Start the systick. */
  regset(SCB.stcs_r, scb_enable, 1);

  regset(RCC.apb2en_r, rcc_spi1en, 1);

  enable_interrupt(IRQ_SPI1);

  uint32_t reg = 0;
  regset(reg, spi_ldma_tx, 0);
  regset(reg, spi_ldma_rx, 0);
  regset(reg, spi_frxth, 0);
  regset(reg, spi_ds, SPI_DATA_SIZE_8_BITS);
  regset(reg, spi_txeie, 0);
  regset(reg, spi_rxneie, 0);
  regset(reg, spi_errie, 0);
  regset(reg, spi_frf, 0);
  regset(reg, spi_nssp, 0);
  regset(reg, spi_ssoe, 0);
  regset(reg, spi_txdmaen, 1);
  regset(reg, spi_rxdmaen, 0);
  SPI1.c_r2 = reg;

  reg = 0;
  regset(reg, spi_bidimode, 0);
  regset(reg, spi_crcen, 0);
  regset(reg, spi_crcnext, 0);
  regset(reg, spi_crcl, 0);
  regset(reg, spi_rxonly, 0);
  regset(reg, spi_ssm, 1);
  regset(reg, spi_ssi, 1);
  regset(reg, spi_lsbfirst, 0);
  regset(reg, spi_spe, 1);
  regset(reg, spi_br, SPI_BAUD_FPCLK_DIV_32);
  regset(reg, spi_mstr, 1);
  regset(reg, spi_cpol, 0);
  regset(reg, spi_cpha, 0);
  SPI1.c_r1 = reg;

  klogf("Initiate xfer\n");
  dma_mem2p_initiate_transfer(dma_chan, dataptr, size * 9);
  klogf("Post\n");

  // for (;;);
}


#endif