#include "project.h"


int
ssd1306_cmds (uint32_t i2c, uint8_t *buf, size_t len, int delay)
{

  int ret = -1;

  while (i2c_lock());

  do {

    if (i2cp_start_transaction (i2c, SSD1306_I2C_ADDRESS, I2C_WRITE))
      break;

    if (i2cp_send (i2c, SSD1306_COMMAND))
      break;

    while (len--)
      if (i2cp_send (i2c, * (buf++)))
        break;

    i2cp_stop (i2c);

    if (delay)
      delay_us (delay);

    ret = 0;
  } while (0);

  i2c_unlock();


  return ret;
}

int
ssd1306_cmd (uint32_t i2c, uint8_t cmd, int delay)
{
  return ssd1306_cmds (i2c, &cmd, 1, delay);
}



void
oled_generate_stream (uint8_t *vram)
{
  memset (vram, 0, DMA_BUF_SZ);
  vram[0] = SSD1306_DATA_CONTINUE;
}




void
oled_cls (uint8_t *vram)
{
  memset (vram + 1, 0, SSD1306_VRAM_SIZE);
}


void
oled_on (uint32_t i2c)
{
  ssd1306_cmd (i2c, SSD1306_DISPLAY_ON, 0);

}


void
oled_off (uint32_t i2c)
{
  ssd1306_cmd (i2c, SSD1306_DISPLAY_OFF, 0);
}



#if 0
void
oled_squirt (void)
{
  unsigned i;
  uint8_t cmds[] = {
    SSD1306_SET_PAGE_ADDR, 0, 0xff,
    SSD1306_SET_COLUMN_ADDR, 0, SSD1306_WIDTH - 1
  };

  ssd1306_cmds (cmds, sizeof (cmds), 0);


  while (i2c_lock());

  i2cp_start_transaction (SSD1306_I2C_ADDRESS, I2C_WRITE);

  for (i = 0; i < DMA_BUF_SZ; ++i)
    i2cp_send (update_buf[i]);

  i2cp_stop();

  i2c_unlock();
}
#endif

void
oled_reset (uint32_t i2c)
{
  uint8_t init[] = {
    SSD1306_DISPLAY_OFF,
    SSD1306_SET_DISPLAY_CLOCK_DIV_RATIO, 0x80,
    SSD1306_SET_MULTIPLEX_RATIO, SSD1306_HEIGHT - 1,
    SSD1306_SET_DISPLAY_OFFSET, 0x0,
    SSD1306_SET_START_LINE | 0x0,
    SSD1306_CHARGE_PUMP, 0x14,
    SSD1306_MEMORY_ADDR_MODE, 0x00,
    SSD1306_SET_SEGMENT_REMAP | 0x1,
    SSD1306_COM_SCAN_DIR_DEC,
    //SSD1306_SET_COM_PINS, 0x12,
    SSD1306_SET_COM_PINS, 0x02,
    //SSD1306_SET_CONTRAST_CONTROL, 0xCF,
    SSD1306_SET_CONTRAST_CONTROL, 0x8F,
    SSD1306_SET_PRECHARGE_PERIOD, 0xF1,
    SSD1306_SET_VCOM_DESELECT, 0x40,
    SSD1306_DISPLAY_ALL_ON_RESUME,
    SSD1306_NORMAL_DISPLAY,
    SSD1306_DISPLAY_ON,
  };

  ssd1306_cmds (i2c, init, sizeof (init), 0);
}


void
oled_const_strip (uint8_t *vram, int x, int xe, uint8_t and, uint8_t or)
{
  uint8_t r;

  for (x++; x <= xe; ++x) {
    r = vram[x] & and;
    vram[x] = r | or;
  }
}


void
oled_blit_strip (uint8_t *vram, int x, int xe, uint8_t mask, int shift,
                 const uint8_t *src)
{
  uint8_t r, s;

  while (x < 0) {
    x++;
    src++;
  };

  if (xe < 0) xe = 0;

  if (x > SSD1306_VRAM_SIZE) xe = SSD1306_VRAM_SIZE;

  if (xe > SSD1306_VRAM_SIZE) xe = SSD1306_VRAM_SIZE;


  if (shift > 0) {
    for (x++; x <= xe; ++x) {
      s = * (src++);
      s <<= shift;
      s &= mask;
      r = vram[x] & ~mask;
      vram[x] = r | s;

    }
  } else if (shift < 0) {
    shift = -shift;

    for (x++; x <= xe; ++x) {
      s = * (src++);
      s >>= shift;
      s &= mask;
      r = vram[x] & ~mask;
      vram[x] = r | s;
    }
  } else {
    for (x++; x <= xe; ++x) {
      s = * (src++);
      s &= mask;
      r = vram[x] & ~mask;
      vram[x] = r | s;
    }
  }
}