#include "json_helper.hpp"
#include "util.hpp"
#include "wayland.hpp"
#include "app.hpp"

#include <algorithm>
#include <json.h>

extern "C" {
#include <afb/afb-binding.h>
#include <systemd/sd-event.h>
}

namespace {
struct afb_instance {
   std::unique_ptr<wl::display> display;
   std::unique_ptr<genivi::controller> controller;
   std::vector<std::unique_ptr<wl::output>> outputs;
   wm::App app;

   afb_instance() : display{new wl::display}, controller{nullptr}, outputs{}, app{} {}

   int init();
};

struct afb_instance *g_afb_instance;

int afb_instance::init() {
   if (!this->display->ok()) {
      return -1;
   }

   this->display->r.add_global_handler("wl_output", [](wl_registry *r,
                                                       uint32_t name,
                                                       uint32_t v) {
      g_afb_instance->outputs.emplace_back(std::make_unique<wl::output>(r, name, v));
   });

   this->display->r.add_global_handler(
      "ivi_controller", [](wl_registry *r, uint32_t name, uint32_t v) {
         g_afb_instance->controller =
            std::make_unique<genivi::controller>(r, name, v);

         // XXX: This protocol needs the output, so lets just add our mapping
         // here...
         g_afb_instance->controller->add_proxy_to_id_mapping(
            g_afb_instance->outputs.back()->proxy.get(),
            wl_proxy_get_id(reinterpret_cast<struct wl_proxy *>(
               g_afb_instance->outputs.back()->proxy.get())));
      });

   // First level objects
   this->display->roundtrip();
   // Second level objects
   this->display->roundtrip();
   // Third level objects
   this->display->roundtrip();

   // Init the app's members
   this->app.display = this->display.get();
   this->app.controller = this->controller.get();

   return 0;
}

//  _       _ _       _                         _    ____
// (_)_ __ (_) |_    | | __ _ _   _  ___  _   _| |_ / /\ \
// | | '_ \| | __|   | |/ _` | | | |/ _ \| | | | __| |  | |
// | | | | | | |_    | | (_| | |_| | (_) | |_| | |_| |  | |
// |_|_| |_|_|\__|___|_|\__,_|\__, |\___/ \__,_|\__| |  | |
//              |_____|       |___/                 \_\/_/
char const *init_layout() {
   if (!g_afb_instance->controller) {
      return "ivi_controller global not available";
   }

   if (g_afb_instance->outputs.empty()) {
      return "no output was set up!";
   }

   auto &c = g_afb_instance->controller;

   auto &o = g_afb_instance->outputs.front();
   auto &s = c->screens.begin()->second;
   auto &layers = c->layers;

   // XXX: Write output dimensions to ivi controller...
   c->output_size = genivi::size{uint32_t(o->width), uint32_t(o->height)};

   // Clear scene
   layers.clear();

   // Clear screen
   s->clear();

   // Setup our dummy scene...
   c->layer_create(100, 0, 0);   // bottom layer, anything else
   c->layer_create(1000, 0, 0);  // top layer, mandelbrot

   auto &l100 = c->layers[100];
   auto &l1k = c->layers[1000];

   // Set layers fullscreen
   l100->set_destination_rectangle(0, 0, o->width, o->height);
   l1k->set_destination_rectangle(0, 0, o->width, o->height);
   l100->set_visibility(1);
   l1k->set_visibility(1);

   // Add layers to screen
   s->set_render_order({100, 1000});

   c->commit_changes();

   g_afb_instance->display->flush();

   return nullptr;
}

int display_event_callback(sd_event_source *evs, int fd, uint32_t events,
                           void *data) {
   if ((events & EPOLLHUP) != 0) {
      logerror("The compositor hung up, dying now.");
      delete g_afb_instance;
      g_afb_instance = nullptr;
      goto error;
   }

   if (events & EPOLLIN) {
      int ret = g_afb_instance->display->dispatch();
      if (ret == -1) {
         logerror("wl_display_dipatch() returned error %d",
                   g_afb_instance->display->get_error());
         goto error;
      }
      g_afb_instance->display->flush();

      // execute pending tasks, that is layout changes etc.
      g_afb_instance->controller->execute_pending();
      g_afb_instance->display->roundtrip();
   }

   return 0;

error:
   sd_event_source_unref(evs);
   return -1;
}

//  _     _           _ _                 _       _ _    ____
// | |__ (_)_ __   __| (_)_ __   __ _    (_)_ __ (_) |_ / /\ \
// | '_ \| | '_ \ / _` | | '_ \ / _` |   | | '_ \| | __| |  | |
// | |_) | | | | | (_| | | | | | (_| |   | | | | | | |_| |  | |
// |_.__/|_|_| |_|\__,_|_|_| |_|\__, |___|_|_| |_|_|\__| |  | |
//                              |___/_____|             \_\/_/
int binding_init_() {
   lognotice("WinMan ver. %s", WINMAN_VERSION_STRING);

   if (g_afb_instance != nullptr) {
      logerror("Wayland context already initialized?");
      return 0;
   }

   if (getenv("XDG_RUNTIME_DIR") == nullptr) {
      logerror("Environment variable XDG_RUNTIME_DIR not set");
      goto error;
   }

   g_afb_instance = new afb_instance;
   if (g_afb_instance->init() == -1) {
      logerror("Could not connect to compositor");
      goto error;
   }

   if (char const *e = init_layout()) {
      logerror("Could not init layout: %s", e);
      goto error;
   }

   {
      int ret = sd_event_add_io(afb_daemon_get_event_loop(), nullptr,
                                g_afb_instance->display->get_fd(), EPOLLIN,
                                display_event_callback, g_afb_instance);
      if (ret < 0) {
         logerror("Could not initialize afb_instance event handler: %d", -ret);
         goto error;
      }
   }

   atexit([] { delete g_afb_instance; });

   return 0;

error:
   delete g_afb_instance;
   g_afb_instance = nullptr;
   return -1;
}

int binding_init() noexcept {
   try {
      return binding_init_();
   } catch (std::exception &e) {
      logerror("Uncaught exception in binding_init(): %s", e.what());
   }
   return -1;
}

} // namespace

#include "afb_binding.inl"

extern "C" const struct afb_binding_v2 afbBindingV2 = {
   "winman", NULL, NULL, winman_verbs, NULL, binding_init, NULL, 1};