#include "Pwm.h"
#include "Config.h"
#include "Core.h"

void PwmGenerator::begin() {
  // Match LEDC_SOURCE_CLOCK_HZ and make the timer calculation deterministic.
  ledcSetClockSource(LEDC_USE_XTAL_CLK);
  pinMode(GPIO_PWM, OUTPUT);
  stop();
}

bool PwmGenerator::start(uint32_t hz, uint8_t dutyPct, ActualPwm &a) {
  stop();
  const uint8_t bits = choosePwmResolution(hz, LEDC_SOURCE_CLOCK_HZ, LEDC_MAX_BITS);
  if (!bits) return false;
  if (!ledcAttachChannel(GPIO_PWM, hz, bits, LEDC_CHANNEL)) return false;
  const uint32_t levels = 1UL << bits;
  const uint32_t duty = (static_cast<uint64_t>(levels) * dutyPct + 50U) / 100U;
  if (!ledcWriteChannel(LEDC_CHANNEL, duty)) { ledcDetach(GPIO_PWM); return false; }
  const uint32_t actualHz = ledcReadFreq(GPIO_PWM);
  if (!actualHz) { ledcDetach(GPIO_PWM); return false; }
  a = {hz, actualHz, 100.0f * duty / levels, bits};
  running_ = true;
  return true;
}

void PwmGenerator::stop() {
  if (running_) ledcDetach(GPIO_PWM);
  pinMode(GPIO_PWM, OUTPUT); digitalWrite(GPIO_PWM, PWM_SAFE_LEVEL);
  running_ = false;
}