polybar/include/components/controller.hpp

#pragma once

#include <thread>

#include "common.hpp"
#include "components/bar.hpp"
#include "components/config.hpp"
#include "components/eventloop.hpp"
#include "components/logger.hpp"
#include "components/signals.hpp"
#include "components/x11/connection.hpp"
#include "components/x11/randr.hpp"
#include "components/x11/tray.hpp"
#include "components/x11/types.hpp"
#include "config.hpp"
#include "utils/inotify.hpp"
#include "utils/process.hpp"
#include "utils/socket.hpp"
#include "utils/string.hpp"

#include "modules/backlight.hpp"
#include "modules/battery.hpp"
#include "modules/bspwm.hpp"
#include "modules/counter.hpp"
#include "modules/cpu.hpp"
#include "modules/date.hpp"
#include "modules/memory.hpp"
#include "modules/menu.hpp"
#include "modules/script.hpp"
#include "modules/text.hpp"
#include "modules/unsupported.hpp"
#include "modules/xbacklight.hpp"
#if ENABLE_I3
#include "modules/i3.hpp"
#endif
#if ENABLE_MPD
#include "modules/mpd.hpp"
#endif
#if ENABLE_NETWORK
#include "modules/network.hpp"
#endif
#if ENABLE_ALSA
#include "modules/volume.hpp"
#endif

LEMONBUDDY_NS

using namespace modules;

class controller {
 public:
  /**
   * Construct controller
   */
  explicit controller(connection& conn, const logger& logger, const config& config,
      unique_ptr<eventloop> eventloop, unique_ptr<bar> bar, unique_ptr<traymanager> tray,
      inotify_watch_t& confwatch)
      : m_connection(conn)
      , m_log(logger)
      , m_conf(config)
      , m_eventloop(forward<decltype(eventloop)>(eventloop))
      , m_bar(forward<decltype(bar)>(bar))
      , m_traymanager(forward<decltype(tray)>(tray))
      , m_confwatch(confwatch) {}

  /**
   * Stop modules and cleanup X components,
   * threads and spawned processes
   */
  ~controller() noexcept {
    g_signals::bar::action_click = nullptr;

    if (m_command) {
      m_log.info("Terminating running shell command");
      m_command->terminate();
    }

    if (m_eventloop) {
      m_log.info("Deconstructing eventloop");
      m_eventloop->set_update_cb(nullptr);
      m_eventloop->set_input_db(nullptr);
      m_eventloop.reset();
    }

    if (m_bar) {
      m_log.info("Deconstructing bar");
      m_bar.reset();
    }

    if (m_traymanager) {
      m_traymanager.reset();
    }

    m_log.info("Interrupting X event loop");
    m_connection.send_dummy_event(m_connection.root());

    if (!m_threads.empty()) {
      m_log.info("Joining active threads");
      for (auto&& thread : m_threads) {
        if (thread.joinable())
          thread.join();
      }
    }

    m_log.info("Waiting for spawned processes");
    while (process_util::notify_childprocess())
      ;

    m_connection.flush();
  }

  /**
   * Setup X environment
   */
  auto bootstrap(bool writeback = false, bool dump_wmname = false) {
    m_writeback = writeback;

    m_log.trace("controller: Initialize X atom cache");
    m_connection.preload_atoms();

    m_log.trace("controller: Query X extension data");
    m_connection.query_extensions();

    // Disabled X extensions {{{
    // const auto& damage_ext = m_connection.extension<xpp::damage::extension>();
    // m_log.trace("controller: Found 'Damage' (first_event: %i, first_error: %i)",
    //     damage_ext->first_event, damage_ext->first_error);
    // const auto& render_ext = m_connection.extension<xpp::render::extension>();
    // m_log.trace("controller: Found 'Render' (first_event: %i, first_error: %i)",
    //     render_ext->first_event, render_ext->first_error);
    // }}}

    const auto& randr_ext = m_connection.extension<xpp::randr::extension>();
    m_log.trace("controller: Found 'RandR' (first_event: %i, first_error: %i)",
        randr_ext->first_event, randr_ext->first_error);

    // Listen for events on the root window to be able to
    // break the blocking wait call when cleaning up
    m_log.trace("controller: Listen for events on the root window");
    try {
      const uint32_t value_list[1]{XCB_EVENT_MASK_STRUCTURE_NOTIFY};
      m_connection.change_window_attributes_checked(
          m_connection.root(), XCB_CW_EVENT_MASK, value_list);
    } catch (const std::exception& err) {
      throw application_error("Failed to change root window event mask: " + string{err.what()});
    }

    g_signals::bar::action_click = bind(&controller::on_mouse_event, this, placeholders::_1);

    m_log.trace("controller: Attach eventloop callbacks");
    m_eventloop->set_update_cb(bind(&controller::on_update, this));
    m_eventloop->set_input_db(bind(&controller::on_unrecognized_action, this, placeholders::_1));

    try {
      m_log.trace("controller: Setup bar");
      m_bar->bootstrap(m_writeback || dump_wmname);
    } catch (const std::exception& err) {
      throw application_error("Failed to setup bar renderer: " + string{err.what()});
    }

    if (dump_wmname) {
      std::cout << m_bar->settings().wmname << std::endl;
      return;
    }

    try {
      if (m_writeback) {
        m_log.trace("controller: Disabling tray (reason: stdout mode)");
        m_traymanager.reset();
      } else if (m_bar->tray().align == alignment::NONE) {
        m_log.trace("controller: Disabling tray (reason: tray-position)");
        m_traymanager.reset();
      } else {
        m_log.trace("controller: Setup tray manager");
        m_traymanager->bootstrap(m_bar->tray());
      }
    } catch (const std::exception& err) {
      m_log.err(err.what());
      m_log.warn("Failed to setup tray, disabling...");
      m_traymanager.reset();
    }

    m_log.trace("controller: Setup user-defined modules");
    bootstrap_modules();
  }

  /**
   * Launch the controller
   */
  auto run() {
    assert(!m_connection.connection_has_error());

    m_log.info("Starting application");
    m_running = true;

    install_sigmask();
    install_confwatch();

    // Wait for term signal in separate thread
    m_threads.emplace_back(thread(&controller::wait_for_signal, this));

    // Activate traymanager in separate thread
    if (!m_writeback && m_traymanager) {
      m_threads.emplace_back(thread(&controller::activate_tray, this));
    }

    // Listen for X events in separate thread
    if (!m_writeback) {
      m_threads.emplace_back(thread(&controller::wait_for_xevent, this));
    }

    // Start event loop
    if (m_eventloop) {
      auto throttle_ms = m_conf.get<double>("settings", "throttle-ms", 10);
      auto throttle_limit = m_conf.get<int>("settings", "throttle-limit", 5);
      m_eventloop->run(chrono::duration<double, std::milli>(throttle_ms), throttle_limit);
    }

    // Wake up signal thread
    if (m_waiting) {
      kill(getpid(), SIGTERM);
    }

    uninstall_sigmask();
    uninstall_confwatch();

    m_running = false;

    return !m_reload;
  }

 protected:
  /**
   * Install sigmask to prevent term signals from being raising
   */
  void install_sigmask() {
    m_log.trace("controller: Set pthread_sigmask to block term signals");

    sigemptyset(&m_waitmask);
    sigaddset(&m_waitmask, SIGINT);
    sigaddset(&m_waitmask, SIGQUIT);
    sigaddset(&m_waitmask, SIGTERM);
    sigaddset(&m_waitmask, SIGUSR1);

    if (pthread_sigmask(SIG_BLOCK, &m_waitmask, nullptr) == -1)
      throw system_error();

    sigemptyset(&m_ignmask);
    sigaddset(&m_ignmask, SIGPIPE);

    if (pthread_sigmask(SIG_BLOCK, &m_ignmask, nullptr) == -1)
      throw system_error();
  }

  /**
   * Uninstall sigmask to allow term signals
   */
  void uninstall_sigmask() {
    m_log.trace("controller: Set pthread_sigmask to unblock term signals");

    if (pthread_sigmask(SIG_UNBLOCK, &m_waitmask, nullptr) == -1)
      throw system_error();
  }

  /**
   * Listen for changes to the config file
   */
  void install_confwatch() {
    if (!m_running)
      return;

    if (!m_confwatch) {
      m_log.trace("controller: Config watch not set, skip...");
      return;
    }

    m_threads.emplace_back([this] {
      this_thread::sleep_for(1s);

      try {
        if (!m_running)
          return;

        m_log.trace("controller: Attach config watch");
        m_confwatch->attach(IN_MODIFY);

        m_log.trace("controller: Wait for config file inotify event");
        m_confwatch->get_event();

        if (!m_running)
          return;

        m_log.info("Configuration file changed");
        kill(getpid(), SIGUSR1);
      } catch (const system_error& err) {
        m_log.err(err.what());
        m_log.trace("controller: Reset config watch");
        m_confwatch.reset();
      }
    });
  }

  void uninstall_confwatch() {
    if (!m_confwatch) {
      return;
    }

    try {
      m_log.info("Removing config watch");
      m_confwatch->remove();
    } catch (const system_error& err) {
    }
  }

  void wait_for_signal() {
    m_log.trace("controller: Wait for signal");
    m_waiting = true;

    int caught_signal = 0;
    sigwait(&m_waitmask, &caught_signal);

    m_log.warn("Termination signal received, shutting down...");
    m_log.trace("controller: Caught signal %d", caught_signal);

    m_reload = (caught_signal == SIGUSR1);
    m_waiting = false;

    if (m_eventloop) {
      m_eventloop->stop();
    }
  }

  void wait_for_xevent() {
    m_log.trace("controller: Listen for X events");

    m_connection.flush();

    while (m_running) {
      shared_ptr<xcb_generic_event_t> evt;

      if (m_connection.connection_has_error()) {
        break;
      }

      if ((evt = m_connection.wait_for_event())) {
        m_connection.dispatch_event(evt);
      }
    }
  }

  void activate_tray() {
    m_log.trace("controller: Activate tray manager");

    try {
      m_traymanager->activate();
    } catch (const std::exception& err) {
      m_log.err(err.what());
      m_log.err("Failed to activate tray manager, disabling...");
      m_traymanager.reset();
    }
  }

  /**
   * Create and initialize bar modules
   */
  void bootstrap_modules() {
    const bar_settings bar{m_bar->settings()};
    string bs{m_conf.bar_section()};
    size_t module_count = 0;

    for (int i = 0; i < 3; i++) {
      alignment align = static_cast<alignment>(i + 1);
      string confkey;

      switch (align) {
        case alignment::LEFT:
          confkey = "modules-left";
          break;
        case alignment::CENTER:
          confkey = "modules-center";
          break;
        case alignment::RIGHT:
          confkey = "modules-right";
          break;
        default:
          break;
      }

      for (auto& module_name : string_util::split(m_conf.get<string>(bs, confkey, ""), ' ')) {
        try {
          auto type = m_conf.get<string>("module/" + module_name, "type");
          module_t module;

          if (type == "internal/counter")
            module.reset(new counter_module(bar, m_log, m_conf, module_name));
          else if (type == "internal/backlight")
            module.reset(new backlight_module(bar, m_log, m_conf, module_name));
          else if (type == "internal/xbacklight")
            module.reset(new xbacklight_module(bar, m_log, m_conf, module_name));
          else if (type == "internal/battery")
            module.reset(new battery_module(bar, m_log, m_conf, module_name));
          else if (type == "internal/bspwm")
            module.reset(new bspwm_module(bar, m_log, m_conf, module_name));
          else if (type == "internal/cpu")
            module.reset(new cpu_module(bar, m_log, m_conf, module_name));
          else if (type == "internal/date")
            module.reset(new date_module(bar, m_log, m_conf, module_name));
          else if (type == "internal/memory")
            module.reset(new memory_module(bar, m_log, m_conf, module_name));
          else if (type == "internal/i3")
            module.reset(new i3_module(bar, m_log, m_conf, module_name));
          else if (type == "internal/mpd")
            module.reset(new mpd_module(bar, m_log, m_conf, module_name));
          else if (type == "internal/volume")
            module.reset(new volume_module(bar, m_log, m_conf, module_name));
          else if (type == "internal/network")
            module.reset(new network_module(bar, m_log, m_conf, module_name));
          else if (type == "custom/text")
            module.reset(new text_module(bar, m_log, m_conf, module_name));
          else if (type == "custom/script")
            module.reset(new script_module(bar, m_log, m_conf, module_name));
          else if (type == "custom/menu")
            module.reset(new menu_module(bar, m_log, m_conf, module_name));
          else
            throw application_error("Unknown module: " + module_name);

          module->set_update_cb(bind(&eventloop::enqueue, m_eventloop.get(),
              eventloop::entry_t{static_cast<int>(event_type::UPDATE)}));
          module->set_stop_cb(bind(&eventloop::enqueue, m_eventloop.get(),
              eventloop::entry_t{static_cast<int>(event_type::CHECK)}));

          module->setup();

          m_eventloop->add_module(align, move(module));

          module_count++;
        } catch (const module_error& err) {
          continue;
        }
      }
    }

    if (module_count == 0)
      throw application_error("No modules created");
  }

  /**
   * Callback for clicked bar actions
   */
  void on_mouse_event(string input) {
    eventloop::entry_t evt{static_cast<int>(event_type::INPUT)};

    if (input.length() > sizeof(evt.data)) {
      m_log.warn("Ignoring input event (size)");
    } else {
      snprintf(evt.data, sizeof(evt.data), "%s", input.c_str());
      m_eventloop->enqueue(evt);
    }
  }

  void on_unrecognized_action(string input) {
    try {
      if (m_command) {
        m_log.warn("Terminating previous shell command");
        m_command->terminate();
      }

      m_log.info("Executing shell command: %s", input);

      m_command = command_util::make_command(input);
      m_command->exec();
      m_command.reset();
    } catch (const application_error& err) {
      m_log.err("controller: Error while forwarding input to shell -> %s", err.what());
    }
  }

  void on_update() {
    string contents{""};
    string separator{m_bar->settings().separator};

    string padding_left(m_bar->settings().padding_left, ' ');
    string padding_right(m_bar->settings().padding_right, ' ');

    auto margin_left = m_bar->settings().module_margin_left;
    auto margin_right = m_bar->settings().module_margin_right;

    for (const auto& block : m_eventloop->modules()) {
      string block_contents;
      bool is_left = false;
      bool is_center = false;
      bool is_right = false;

      if (block.first == alignment::LEFT)
        is_left = true;
      else if (block.first == alignment::CENTER)
        is_center = true;
      else if (block.first == alignment::RIGHT)
        is_right = true;

      for (const auto& module : block.second) {
        auto module_contents = module->contents();

        if (module_contents.empty())
          continue;

        if (!block_contents.empty() && !separator.empty())
          block_contents += separator;

        if (!(is_left && module == block.second.front()))
          block_contents += string(margin_left, ' ');

        block_contents += module->contents();

        if (!(is_right && module == block.second.back()))
          block_contents += string(margin_right, ' ');
      }

      if (block_contents.empty())
        continue;

      if (is_left) {
        contents += "%{l}";
        contents += padding_left;
      } else if (is_center) {
        contents += "%{c}";
      } else if (is_right) {
        contents += "%{r}";
        block_contents += padding_right;
      }

      block_contents = string_util::replace_all(block_contents, "B-}%{B#", "B#");
      block_contents = string_util::replace_all(block_contents, "F-}%{F#", "F#");
      block_contents = string_util::replace_all(block_contents, "T-}%{T", "T");
      contents += string_util::replace_all(block_contents, "}%{", " ");
    }

    if (m_writeback) {
      std::cout << contents << std::endl;
    } else {
      m_bar->parse(contents);
    }
  }

 private:
  connection& m_connection;
  registry m_registry{m_connection};
  const logger& m_log;
  const config& m_conf;
  unique_ptr<eventloop> m_eventloop;
  unique_ptr<bar> m_bar;
  unique_ptr<traymanager> m_traymanager;

  stateflag m_running{false};
  stateflag m_reload{false};
  stateflag m_waiting{false};

  sigset_t m_waitmask;
  sigset_t m_ignmask;

  inotify_watch_t& m_confwatch;

  vector<thread> m_threads;

  command_util::command_t m_command;

  bool m_writeback = false;
};

namespace {
  /**
   * Configure injection module
   */
  template <typename T = unique_ptr<controller>>
  di::injector<T> configure_controller(inotify_watch_t& confwatch) {
    // clang-format off
    return di::make_injector(
        di::bind<>().to(confwatch),
        configure_connection(),
        configure_logger(),
        configure_config(),
        configure_eventloop(),
        configure_bar(),
        configure_traymanager());
    // clang-format on
  }
}

LEMONBUDDY_NS_END