#ifndef PLATFORM_NATIVE

#include "drivers/Esp32DriverRGBW.h"

#include <driver/rmt_encoder.h>
#include <esp_check.h>

// Timing constants, in ns
static constexpr uint32_t RESOLUTION_HZ = 20 * 1000 * 1000; // one RMT tick = 50 ns
static constexpr uint32_t TICK_NS = 1000 * 1000 * 1000 / RESOLUTION_HZ;
static constexpr uint32_t T0H = 300;
static constexpr uint32_t T0L = 900;
static constexpr uint32_t T1H = 600;
static constexpr uint32_t T1L = 600;

static rmt_symbol_word_t symbol(uint32_t highNs, uint32_t lowNs)
{
  rmt_symbol_word_t s = {};
  s.duration0 = highNs / TICK_NS;
  s.level0 = 1;
  s.duration1 = lowNs / TICK_NS;
  s.level1 = 0;
  return s;
}

void Esp32DriverRGBW::begin(int gpio)
{
  transmitting_ = false;

  rmt_tx_channel_config_t channelConfig = {};
  channelConfig.gpio_num = static_cast<gpio_num_t>(gpio);
  channelConfig.clk_src = RMT_CLK_SRC_DEFAULT;
  channelConfig.resolution_hz = RESOLUTION_HZ;
  channelConfig.mem_block_symbols = 64; // one block, refilled from the interrupt
  channelConfig.trans_queue_depth = 4;
  ESP_ERROR_CHECK(rmt_new_tx_channel(&channelConfig, &channel_));

  // Every byte goes out MSB first, one RMT symbol per bit - the strip's own byte order
  // (g, r, b, w) is already how LedStripRGBW lays the data out in memory.
  rmt_bytes_encoder_config_t encoderConfig = {};
  encoderConfig.bit0 = symbol(T0H, T0L);
  encoderConfig.bit1 = symbol(T1H, T1L);
  encoderConfig.flags.msb_first = 1;
  ESP_ERROR_CHECK(rmt_new_bytes_encoder(&encoderConfig, &encoder_));

  ESP_ERROR_CHECK(rmt_enable(channel_));
}

void Esp32DriverRGBW::end()
{
  waitForTransmissionToFinish();
  ESP_ERROR_CHECK(rmt_disable(channel_));
  ESP_ERROR_CHECK(rmt_del_encoder(encoder_));
  ESP_ERROR_CHECK(rmt_del_channel(channel_));
  encoder_ = nullptr;
  channel_ = nullptr;
}

void Esp32DriverRGBW::writeSync(const uint32_t *rgbwData, int numLeds)
{
  writeAsync(rgbwData, numLeds);
  waitForTransmissionToFinish();
}

void Esp32DriverRGBW::writeAsync(const uint32_t *rgbwData, int numLeds)
{
  waitForTransmissionToFinish();
  rmt_transmit_config_t transmitConfig = {};
  transmitConfig.loop_count = 0;
  ESP_ERROR_CHECK(rmt_transmit(channel_, encoder_, rgbwData, numLeds * 4, &transmitConfig));
  transmitting_ = true;
}

bool Esp32DriverRGBW::waitForTransmissionToFinish(int waitMs)
{
  if (!transmitting_)
    return true;
  if (rmt_tx_wait_all_done(channel_, waitMs) == ESP_OK)
  {
    transmitting_ = false;
    return true;
  }
  else
    return false;
}

#endif