#include "common.hh"

#include <algorithm>
#include <math.h>

#include "animation.hh"
#include "args.hh"
#include "blissful_monitor.hh"
#include "cairo.hh"
#include "fake_monitor.hh"
#include "icecc.hh"
#include "monitor.hh"
#include "pango.hh"

namespace {

class IceccMonMonImpl : public IceccMonMon, virtual Monitor::Observer {
public:
  IceccMonMonImpl(std::shared_ptr<PollLooper> const& looper, unsigned columns)
    : IceccMonMon(looper), connected_(false), max_jobs_(0), jobs_(0),
      requests_(0), force_columns_(columns) {
  }

  void connect(Args const* args) override {
    std::unique_ptr<Monitor> monitor;
#if FAKE_MONITOR
    monitor = FakeMonitor::create(looper_);
#else
    monitor = Monitor::create(looper_);
#endif
    monitor_ = BlissfulMonitor::create(looper_, std::move(monitor));
    monitor_->add_observer(this);
    monitor_->connect(args->arg("network", ""),
                      args->arg("scheduler", ""));
  }

protected:
  void width_changed() override {
    job_pattern_.reset();
  }

#if FAKE_MONITOR
  void do_toggle_fakes() override {
    monitor_->toggle_fakes();
  }
#endif

private:
  class MachineAnimation;

  struct Machine : virtual Animator::AnimationObserver {
    uint32_t id;
    Monitor::Machine data;
    unsigned jobs;
    unsigned requests;
    double x;
    std::shared_ptr<MachineAnimation> animation;

    explicit Machine(uint32_t id)
      : id(id), jobs(0), requests(0), x(0.0) {
    }

    Machine(Machine const&) = delete;
    Machine& operator=(Machine const&) = delete;

    ~Machine() override {
      assert(!animation);
    }

    bool operator<(Machine const& machine) const {
      if (data.name < machine.data.name) return true;
      if (data.name > machine.data.name) return false;
      return id < machine.id;
    }

    void ticked(Animator*, Animation*, double value) override {
      x = value;
    }

    void stopped(Animator*, Animation*) override {
      x = static_cast<double>(jobs) / data.max_jobs;
      animation.reset();
    }
  };

  class MachineAnimation : public Animation {
  public:
    explicit MachineAnimation(Machine* machine)
      : machine_(machine), last_(0.0) {
    }

    bool tick(double duration, double* value) override {
      auto target = static_cast<double>(machine_->jobs)
        / machine_->data.max_jobs;
      if (duration == 0.0) {
        last_ = duration;
        *value = machine_->x;
        return machine_->x != target;
      } else {
        double diff = target - machine_->x;
        double max = (duration - last_) * .5;
        last_ = duration;
        if (fabs(diff) > max) {
          diff = diff < 0.0 ? -max : max;
          *value = machine_->x + diff;
          return true;
        } else {
          *value = target;
          return false;
        }
      }
    }

  private:
    Machine* machine_;
    double last_;
  };


  void state(Monitor*, Monitor::State state) override {
    switch (state) {
    case Monitor::SEARCHING:
      connected_ = false;
      stop_all_animations();
      machines_.clear();
      max_jobs_ = 0;
      jobs_ = 0;
      requests_ = 0;
      if (!wnd_) return;
      draw();
      break;
    case Monitor::CONNECTED:
      connected_ = true;
      draw();
      break;
    }
  }

  void stop_all_animations() override {
    if (!animator_) return;
    for (auto& machine : machines_) {
      if (machine->animation) animator_->stop(machine->animation.get());
    }
  }

  void internal_quit() override {
    monitor_->disconnect();
  }

  void update(Machine* machine) {
    auto old = machine->data.max_jobs;
    machine->data = monitor_->machine(machine->id);
    if (old < machine->data.max_jobs) {
      max_jobs_ += machine->data.max_jobs - old;
      if (machine->jobs) animate(machine);
    } else if (old > machine->data.max_jobs) {
      max_jobs_ -= old - machine->data.max_jobs;
      if (machine->jobs) animate(machine);
    }
  }

  void draw_content(cairo_t* cairo, PangoLayout* layout, uint16_t w, uint16_t h)
      override {
    auto const pad_x = std::min(9.0, w / 20.0), pad_y = pad_x;
    auto const margin_x = std::min(7.5, w / 20.0), margin_y = margin_x;
    auto y = pad_y;
    auto const columns = force_columns_ ? force_columns_ : std::max(1, w / h);
    auto const box_width = (w - pad_x) / columns - pad_x;
    auto const box_height = box_height_ + margin_y * 2;
    if (!job_pattern_) {
      job_pattern_.reset(cairo_pattern_create_linear(0.0, 0.0, box_width, 0.0));
      cairo_pattern_add_color_stop_rgb(job_pattern_.get(), 0.000000,
                                       0.000000, 0.000000, 0.000000);
      cairo_pattern_add_color_stop_rgb(job_pattern_.get(), 0.594324,
                                       0.729412, 0.000000, 0.000000);
      cairo_pattern_add_color_stop_rgb(job_pattern_.get(), 0.809683,
                                       1.000000, 0.545098, 0.196078);
      cairo_pattern_add_color_stop_rgb(job_pattern_.get(), 0.899833,
                                       0.972549, 0.937255, 0.074510);
      cairo_pattern_add_color_stop_rgb(job_pattern_.get(), 1.000000,
                                       0.976471, 0.968627, 0.831373);
    }
    pango_layout_set_width(layout,
                           (box_width - margin_x * 2) * PANGO_SCALE);
    unsigned col = 0;
    for (auto const& machine : machines_) {
      pango_layout_set_text(layout, machine->data.name.data(),
                            machine->data.name.size());
      auto x = pad_x + col * (box_width + pad_x);
      rounded_path(cairo, x, y, box_width, box_height);
      cairo_set_source_rgba(cairo, 0.1, 0.1, 0.1, 0.7);

      if (machine->x > 0.0) {
        cairo_fill_preserve(cairo);
        auto old = cairo::unique_path(cairo_copy_path(cairo));
        cairo_new_path(cairo);
        cairo_rectangle(cairo, x, y, machine->x * box_width, box_height);
        cairo_clip(cairo);
        cairo_append_path(cairo, old.get());
        cairo_matrix_t matrix;
        cairo_matrix_init_translate(&matrix, -x, 0);
        cairo_pattern_set_matrix(job_pattern_.get(), &matrix);
        cairo_set_source(cairo, job_pattern_.get());
        cairo_fill(cairo);
        cairo_reset_clip(cairo);
      } else {
        cairo_fill(cairo);
      }
      if (machine->requests > 0) {
        auto radius = box_height / 10.0;
        cairo_set_line_width(cairo, 1.5);
        cairo_new_path(cairo);
        cairo_move_to(cairo, x + box_width - radius, y);
        cairo_rel_line_to(cairo,
                          -(machine->requests * (box_width - radius * 2))
                          / requests_, 0);
        cairo_set_source_rgb(cairo, 0, 0.6, 0);
        cairo_stroke(cairo);
      }

      cairo_move_to(cairo, x + margin_x, y + margin_y);
      pango_cairo_layout_path(cairo, layout);
      cairo_set_source_rgb(cairo, 0.0, 0.0, 0.0);
      cairo_set_line_cap(cairo, CAIRO_LINE_CAP_ROUND);
      cairo_set_line_width(cairo, 2.0);
      cairo_stroke(cairo);
      cairo_set_source_rgb(cairo, 1.0, 1.0, 1.0);
      cairo_move_to(cairo, x + margin_x, y + margin_y);
      pango_cairo_show_layout(cairo, layout);
      if (++col == columns) {
        col = 0;
        y += box_height + pad_y * 2;
        if (y >= h) break;
      }
    }
  }

  void added_machine(Monitor*, uint32_t id) override {
    auto machine = std::make_unique<Machine>(id);
    update(machine.get());
    machines_.emplace(
        std::lower_bound(machines_.begin(), machines_.end(), machine,
                         compare_machine),
        std::move(machine));
    draw();
  }

  static bool compare_machine(std::unique_ptr<Machine> const& m1,
                              std::unique_ptr<Machine> const& m2) {
    return *m1 < *m2;
  }

  void updated_machine(Monitor*, uint32_t id) override {
    for (auto& machine : machines_) {
      if (machine->id == id) {
        auto old = machine->data.name;
        update(machine.get());
        if (machine->data.name != old) {
          // TODO: Perhaps remove and insert instead?
          std::sort(machines_.begin(), machines_.end(), compare_machine);
        }
        draw();
        return;
      }
    }
    assert(false);
  }

  void removed_machine(Monitor*, uint32_t id) override {
    for (auto it = machines_.begin(); it != machines_.end(); ++it) {
      if ((*it)->id == id) {
        max_jobs_ -= (*it)->data.max_jobs;
        requests_ -= (*it)->requests;
        jobs_ -= (*it)->jobs;
        if (animator_) animator_->stop((*it)->animation.get());
        machines_.erase(it);
        draw();
        return;
      }
    }
    assert(false);
  }

  void added_job(Monitor*, uint32_t source, uint32_t target) override {
    if (source == target) {
      for (auto& machine : machines_) {
        if (machine->id == source) {
          ++machine->jobs;
          animate(machine.get());
        }
      }
    } else {
      for (auto& machine : machines_) {
        if (machine->id == source) {
          ++machine->requests;
        }
        if (machine->id == target) {
          ++machine->jobs;
          animate(machine.get());
        }
      }
      ++requests_;
    }
    ++jobs_;
    draw();
  }

  void removed_job(Monitor*, uint32_t source, uint32_t target) override {
    if (source == target) {
      for (auto& machine : machines_) {
        if (machine->id == source) {
          --machine->jobs;
          animate(machine.get());
        }
      }
    } else {
      for (auto& machine : machines_) {
        if (machine->id == source) {
          --machine->requests;
        }
        if (machine->id == target) {
          --machine->jobs;
          animate(machine.get());
        }
      }
      --requests_;
    }
    --jobs_;
    draw();
  }

  void animate(Machine* machine) {
    if (!animator_) return;
    if (machine->animation) return;
    machine->animation = std::make_unique<MachineAnimation>(machine);
    animator_->start(machine->animation, machine);
  }

  std::unique_ptr<Monitor> monitor_;
  bool connected_;
  std::vector<std::unique_ptr<Machine>> machines_;
  unsigned max_jobs_;
  unsigned jobs_;
  unsigned requests_;
  cairo::unique_pattern job_pattern_;
  unsigned force_columns_;
};

}  // namespace

IceccMonMon::IceccMonMon(std::shared_ptr<PollLooper> const& looper)
  : MonMon(looper) {}

std::unique_ptr<IceccMonMon> create_icecc_monmon(
    std::shared_ptr<PollLooper> const& looper, unsigned columns) {
  return std::make_unique<IceccMonMonImpl>(looper, columns);
}