#include "dac7678_output.h"
#include "esphome/core/hal.h"
#include "esphome/core/helpers.h"
#include "esphome/core/log.h"

namespace esphome::dac7678 {

static const char *const TAG = "dac7678";

static const uint8_t DAC7678_REG_INPUT_N = 0x00;
static const uint8_t DAC7678_REG_SELECT_UPDATE_N = 0x10;
static const uint8_t DAC7678_REG_WRITE_N_UPDATE_ALL = 0x20;
static const uint8_t DAC7678_REG_WRITE_N_UPDATE_N = 0x30;
static const uint8_t DAC7678_REG_POWER = 0x40;
static const uint8_t DAC7678_REG_CLEAR_CODE = 0x50;
static const uint8_t DAC7678_REG_LDAC = 0x60;
static const uint8_t DAC7678_REG_SOFTWARE_RESET = 0x70;
static const uint8_t DAC7678_REG_INTERNAL_REF_0 = 0x80;
static const uint8_t DAC7678_REG_INTERNAL_REF_1 = 0x90;

void DAC7678Output::setup() {
  ESP_LOGV(TAG, "Resetting device");

  // Reset device
  if (!this->write_byte_16(DAC7678_REG_SOFTWARE_RESET, 0x0000)) {
    ESP_LOGE(TAG, "Reset failed");
    this->mark_failed();
    return;
  } else {
    ESP_LOGV(TAG, "Reset succeeded");
  }

  delayMicroseconds(1000);

  // Set internal reference
  if (this->internal_reference_) {
    if (!this->write_byte_16(DAC7678_REG_INTERNAL_REF_0, 1 << 4)) {
      ESP_LOGE(TAG, "Set internal reference failed");
      this->mark_failed();
      return;
    } else {
      ESP_LOGV(TAG, "Internal reference enabled");
    }
  }
}

void DAC7678Output::dump_config() {
  if (this->is_failed()) {
    ESP_LOGE(TAG, "Setting up DAC7678 failed!");
  } else {
    ESP_LOGCONFIG(TAG, "DAC7678 initialised");
  }
}

void DAC7678Output::register_channel(DAC7678Channel *channel) {
  auto c = channel->channel_;
  this->min_channel_ = std::min(this->min_channel_, c);
  this->max_channel_ = std::max(this->max_channel_, c);
  channel->set_parent(this);
  ESP_LOGV(TAG, "Registered channel: %01u", channel->channel_);
}

void DAC7678Output::set_channel_value_(uint8_t channel, uint16_t value) {
  if (channel >= std::size(this->dac_input_reg_))
    return;
  if (this->dac_input_reg_[channel] != value) {
    ESP_LOGV(TAG, "Channel %01u: input_reg=%04u ", channel, value);

    if (!this->write_byte_16(DAC7678_REG_WRITE_N_UPDATE_N | channel, value << 4)) {
      this->status_set_warning();
      return;
    }
  }
  this->dac_input_reg_[channel] = value;
  this->status_clear_warning();
}

void DAC7678Channel::write_state(float state) {
  const float input_rounded = roundf(state * this->full_scale_);
  auto input = static_cast<uint16_t>(input_rounded);
  this->parent_->set_channel_value_(this->channel_, input);
}

}  // namespace esphome::dac7678
