polybar/include/modules/battery.hpp

#pragma once

#include "config.hpp"
#include "drawtypes/animation.hpp"
#include "drawtypes/label.hpp"
#include "drawtypes/progressbar.hpp"
#include "drawtypes/ramp.hpp"
#include "modules/meta.hpp"
#include "utils/file.hpp"
#include "utils/inotify.hpp"
#include "utils/string.hpp"

LEMONBUDDY_NS

namespace modules {
  enum class battery_state { NONE = 0, UNKNOWN, CHARGING, DISCHARGING, FULL };
  class battery_module : public inotify_module<battery_module> {
   public:
    using inotify_module::inotify_module;

    void setup() {
      // Load configuration values {{{

      m_battery = m_conf.get<string>(name(), "battery", "BAT0");
      m_adapter = m_conf.get<string>(name(), "adapter", "ADP1");
      m_fullat = m_conf.get<int>(name(), "full-at", 100);

      m_path_capacity = string_util::replace(PATH_BATTERY_CAPACITY, "%battery%", m_battery);
      m_path_adapter = string_util::replace(PATH_ADAPTER_STATUS, "%adapter%", m_adapter);

      // }}}
      // Validate paths {{{

      if (!file_util::exists(m_path_capacity))
        throw module_error("The file '" + m_path_capacity + "' does not exist");
      if (!file_util::exists(m_path_adapter))
        throw module_error("The file '" + m_path_adapter + "' does not exist");

      // }}}
      // Load state and capacity level {{{

      m_percentage = current_percentage();
      m_state = current_state();

      // }}}
      // Add formats and elements {{{

      m_formatter->add(FORMAT_CHARGING, TAG_LABEL_CHARGING,
          {TAG_BAR_CAPACITY, TAG_RAMP_CAPACITY, TAG_ANIMATION_CHARGING, TAG_LABEL_CHARGING});
      m_formatter->add(FORMAT_DISCHARGING, TAG_LABEL_DISCHARGING,
          {TAG_BAR_CAPACITY, TAG_RAMP_CAPACITY, TAG_LABEL_DISCHARGING});
      m_formatter->add(
          FORMAT_FULL, TAG_LABEL_FULL, {TAG_BAR_CAPACITY, TAG_RAMP_CAPACITY, TAG_LABEL_FULL});

      if (m_formatter->has(TAG_ANIMATION_CHARGING, FORMAT_CHARGING))
        m_animation_charging = load_animation(m_conf, name(), TAG_ANIMATION_CHARGING);
      if (m_formatter->has(TAG_BAR_CAPACITY))
        m_bar_capacity = load_progressbar(m_bar, m_conf, name(), TAG_BAR_CAPACITY);
      if (m_formatter->has(TAG_RAMP_CAPACITY))
        m_ramp_capacity = load_ramp(m_conf, name(), TAG_RAMP_CAPACITY);
      if (m_formatter->has(TAG_LABEL_CHARGING, FORMAT_CHARGING)) {
        m_label_charging = load_optional_label(m_conf, name(), TAG_LABEL_CHARGING, "%percentage%");
      }
      if (m_formatter->has(TAG_LABEL_DISCHARGING, FORMAT_DISCHARGING)) {
        m_label_discharging =
            load_optional_label(m_conf, name(), TAG_LABEL_DISCHARGING, "%percentage%");
      }
      if (m_formatter->has(TAG_LABEL_FULL, FORMAT_FULL)) {
        m_label_full = load_optional_label(m_conf, name(), TAG_LABEL_FULL, "%percentage%");
      }

      // }}}
      // Create inotify watches {{{

      watch(m_path_capacity, IN_ACCESS);
      watch(m_path_adapter, IN_ACCESS);

      // }}}
    }

    void start() {
      inotify_module::start();
      m_threads.emplace_back(thread(&battery_module::subthread, this));
    }

    void teardown() {
      wakeup();
    }

    bool on_event(inotify_event* event) {
      if (event != nullptr) {
        m_log.trace("%s: %s", name(), event->filename);
        m_notified.store(true, std::memory_order_relaxed);
      }

      auto state = current_state();
      int percentage = m_percentage;

      if (state != battery_state::FULL) {
        percentage = current_percentage();
      }

      // Ignore unchanged state
      if (event != nullptr && m_state == state && m_percentage == percentage) {
        return false;
      }

      m_percentage = percentage;
      m_state = state;

      if (m_label_charging) {
        m_label_charging->reset_tokens();
        m_label_charging->replace_token("%percentage%", to_string(m_percentage) + "%");
      }
      if (m_label_discharging) {
        m_label_discharging->reset_tokens();
        m_label_discharging->replace_token("%percentage%", to_string(m_percentage) + "%");
      }
      if (m_label_full) {
        m_label_full->reset_tokens();
        m_label_full->replace_token("%percentage%", to_string(m_percentage) + "%");
      }

      return true;
    }

    string get_format() const {
      if (m_state == battery_state::FULL)
        return FORMAT_FULL;
      else if (m_state == battery_state::CHARGING)
        return FORMAT_CHARGING;
      else
        return FORMAT_DISCHARGING;
    }

    bool build(builder* builder, string tag) const {
      if (tag == TAG_ANIMATION_CHARGING)
        builder->node(m_animation_charging->get());
      else if (tag == TAG_BAR_CAPACITY) {
        builder->node(m_bar_capacity->output(m_percentage));
      } else if (tag == TAG_RAMP_CAPACITY)
        builder->node(m_ramp_capacity->get_by_percentage(m_percentage));
      else if (tag == TAG_LABEL_CHARGING)
        builder->node(m_label_charging);
      else if (tag == TAG_LABEL_DISCHARGING)
        builder->node(m_label_discharging);
      else if (tag == TAG_LABEL_FULL)
        builder->node(m_label_full);
      else
        return false;
      return true;
    }

   protected:
    /**
     * Read the current adapter state from
     */
    battery_state current_state() {
      auto adapter_status = file_util::get_contents(m_path_adapter);

      if (adapter_status.empty()) {
        return battery_state::UNKNOWN;
      } else if (adapter_status[0] == '0') {
        return battery_state::DISCHARGING;
      } else if (adapter_status[0] != '1') {
        return battery_state::UNKNOWN;
      } else if (m_percentage < m_fullat) {
        return battery_state::CHARGING;
      } else {
        return battery_state::FULL;
      }
    }

    /**
     * Get the current capacity level
     */
    int current_percentage() {
      auto capacity = file_util::get_contents(m_path_capacity);
      auto value = math_util::cap<int>(std::atof(capacity.c_str()), 0, 100);

      if (value >= m_fullat) {
        return 100;
      } else {
        return value;
      }
    }

    /**
     * Subthread runner that emit update events
     * to refresh <animation-charging> in case it is used.
     *
     * Will also poll for events as fallback for systems that
     * doesn't report inotify events for files on sysfs
     */
    void subthread() {
      chrono::duration<double> dur = 1s;

      if (m_animation_charging) {
        dur = chrono::duration<double>(float(m_animation_charging->framerate()) / 1000.0f);
      }

      const int interval = m_conf.get<float>(name(), "poll-interval", 3.0f) / dur.count();

      while (running()) {
        for (int i = 0; running() && i < interval; ++i) {
          if (m_state == battery_state::CHARGING) {
            broadcast();
          }
          sleep(dur);
        }

        if (!running() || m_state == battery_state::CHARGING) {
          continue;
        }

        if (!m_notified.load(std::memory_order_relaxed)) {
          file_util::get_contents(m_path_capacity);
        }
      }

      m_log.trace("%s: End of subthread", name());
    }

   private:
    static constexpr auto FORMAT_CHARGING = "format-charging";
    static constexpr auto FORMAT_DISCHARGING = "format-discharging";
    static constexpr auto FORMAT_FULL = "format-full";

    static constexpr auto TAG_ANIMATION_CHARGING = "<animation-charging>";
    static constexpr auto TAG_BAR_CAPACITY = "<bar-capacity>";
    static constexpr auto TAG_RAMP_CAPACITY = "<ramp-capacity>";
    static constexpr auto TAG_LABEL_CHARGING = "<label-charging>";
    static constexpr auto TAG_LABEL_DISCHARGING = "<label-discharging>";
    static constexpr auto TAG_LABEL_FULL = "<label-full>";

    animation_t m_animation_charging;
    ramp_t m_ramp_capacity;
    progressbar_t m_bar_capacity;
    label_t m_label_charging;
    label_t m_label_discharging;
    label_t m_label_full;

    string m_battery;
    string m_adapter;
    string m_path_capacity;
    string m_path_adapter;

    battery_state m_state = battery_state::UNKNOWN;
    std::atomic_int m_percentage{0};

    stateflag m_notified{false};

    int m_fullat = 100;
  };
}

LEMONBUDDY_NS_END