//
// Created by mfritzsc on 7/11/17.
//

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

#include <cstdio>
#include <memory>

#include <cassert>

#include <json-c/json.h>

#include <bits/signum.h>
#include <csignal>
#include <fstream>
#include <json.hpp>

namespace wm {

namespace {
App *g_app;

using json = nlohmann::json;

struct wm::area area_from_json(json const &j) {
   DB(j);
   return wm::area{
      j["name"].get<std::string>(),
      {
         get<int32_t>(j["width"]), get<int32_t>(j["height"]),
         get<int32_t>(j["x"]), get<int32_t>(j["y"]),
      },
      get<uint32_t>(j["zorder"]),
   };
}

result<struct layout> layout_from_json(json const &j) {
   DB(j);
   auto &ja = j["areas"];

   auto l = layout{j["name"].get<std::string>(), uint32_t(ja.size()), {}};

   if (ja.size() > layout::MAX_N_AREAS) {
      return Err<struct layout>("Invalid number of areas in layout");
   }

   logdebug("Loading layout '%s' with %u areas", l.name.c_str(),
            unsigned(ja.size()));

   std::transform(std::cbegin(ja), std::cend(ja), std::begin(l.areas),
                  area_from_json);

   return Ok(l);
}

result<json> file_to_json(char const *filename) {
   std::ifstream i(filename);
   if (i.fail()) {
      return Err<json>("Could not open config file");
   }
   json j;
   i >> j;
   return Ok(j);
}

struct result<layouts_type> load_layout(char const *filename) {
   DB("loading layout from " << filename);

   auto j = file_to_json(filename);
   if (j.is_err()) {
      return Err<layouts_type>(j.unwrap_err());
   }
   json jlayouts = j.unwrap();

   auto layouts = layouts_type();
   layouts.reserve(jlayouts.size());
   std::transform(std::cbegin(jlayouts), std::cend(jlayouts),
                  std::back_inserter(layouts), layout_from_json);

   return Ok(layouts);
}

struct result<surface_id_to_layer_map>
   load_layer_ids(char const *filename) {
   DB("loading IDs from " << filename);

   auto j = file_to_json(filename);
   if (j.is_err()) {
      return Err<surface_id_to_layer_map>(j.unwrap_err());
   }
   json jids = j.unwrap();

   return to_surface_id_to_layer_map(jids);
}

}  // namespace

//       _                    _                  _                 _
//   ___| | __ _ ___ ___     / \   _ __  _ __   (_)_ __ ___  _ __ | |
//  / __| |/ _` / __/ __|   / _ \ | '_ \| '_ \  | | '_ ` _ \| '_ \| |
// | (__| | (_| \__ \__ \  / ___ \| |_) | |_) | | | | | | | | |_) | |
//  \___|_|\__,_|___/___/ /_/   \_\ .__/| .__/  |_|_| |_| |_| .__/|_|
//                                |_|   |_|                 |_|
App::App(wl::display *d)
   : api{this},
     chooks{this},
     display{d},
     controller{},
     outputs(),
     layouts(),  // load_layout("../layout.json").unwrap()),
     surface2layer(load_layer_ids("../ids.json").unwrap()) {
   // layouts(load_layout("../layout.json").unwrap()) {
   assert(g_app == nullptr);
   g_app = this;

   try {
      auto l = load_layout("../layout.json");
      if (l.is_err()) {
         logerror("Coult not load layout configuration: %s", l.err().value());
      }
   } catch (std::exception &e) {
      logerror("Coult not load layout configuration: %s", e.what());
   }
}

App::~App() { g_app = nullptr; }

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

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

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

         // Init controller hooks
         this->controller->chooks = &this->chooks;

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

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

   return init_layout();
}

int App::dispatch_events() {
   int ret = this->display->dispatch();
   if (ret == -1) {
      logerror("wl_display_dipatch() returned error %d",
               this->display->get_error());
      return -1;
   }
   this->display->flush();

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

   return 0;
}

//  _       _ _       _                         _    ____
// (_)_ __ (_) |_    | | __ _ _   _  ___  _   _| |_ / /\ \
// | | '_ \| | __|   | |/ _` | | | |/ _ \| | | | __| |  | |
// | | | | | | |_    | | (_| | |_| | (_) | |_| | |_| |  | |
// |_|_| |_|_|\__|___|_|\__,_|\__, |\___/ \__,_|\__| |  | |
//              |_____|       |___/                 \_\/_/
int App::init_layout() {
   if (!this->controller) {
      logerror("ivi_controller global not available");
      return -1;
   }

   if (this->outputs.empty()) {
      logerror("no output was set up!");
      return -1;
   }

   auto &c = this->controller;

   auto &o = this->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();

   // Quick and dirty setup of layers
   // XXX: This likely needs to be sorted by order (note, we don't (yet?)
   // do any zorder arrangement).
   for (auto const &i : this->surface2layer.mapping) {
      c->layer_create(i.layer_id, o->width, o->height);
      auto &l = layers[i.layer_id];
      l->set_destination_rectangle(0, 0, o->width, o->height);
      l->set_visibility(1);
      logdebug("Setting up layer %s (%d) for surfaces %d-%d", i.name.c_str(),
               i.layer_id, i.id_min, i.id_max);
   }

   // Add layers to screen (XXX: are they sorted correctly?)
   s->set_render_order(this->surface2layer.layers);

   c->commit_changes();

   this->display->flush();

   return 0;
}

//                      _          _   _____                 _
//  _ __  _ __ _____  _(_) ___  __| | | ____|_   _____ _ __ | |_ ___
// | '_ \| '__/ _ \ \/ / |/ _ \/ _` | |  _| \ \ / / _ \ '_ \| __/ __|
// | |_) | | | (_) >  <| |  __/ (_| | | |___ \ V /  __/ | | | |_\__ \
// | .__/|_|  \___/_/\_\_|\___|\__,_| |_____| \_/ \___|_| |_|\__|___/
// |_|
void App::surface_created(uint32_t surface_id) {
   DB("surface_id is " << surface_id);
   int layer_id =
      this->surface2layer.get_layer_for_surface(surface_id).value_or(-1);
   if (layer_id == -1) {
      logerror("Surface %d (0x%x) is not part of any layer!", surface_id,
               surface_id);
   } else {
      auto rect = this->surface2layer.get_rect_for_surface(surface_id).value();
      this->controller->add_task(
         "fullscreen surface",
         [layer_id, surface_id, rect](struct genivi::controller *c) {
            auto &s = c->surfaces[surface_id];

            int x = rect.x;
            int y = rect.y;
            int w = rect.w;
            int h = rect.h;

            if (w < 0) {
               w = c->output_size.w + 1 + w;
            }
            if (h < 0) {
               h = c->output_size.h + 1 + h;
            }
            logdebug("Computed rect={ %d, %d, %d, %d }", x, y, w, h);

            s->set_configuration(w, h);
            s->set_source_rectangle(0, 0, w, h);
            s->set_destination_rectangle(x, y, w, h);

            s->set_visibility(1);
            c->layers[layer_id]->add_surface(s.get());
            logdebug("Surface %u now on layer %u", surface_id, layer_id);
         });
   }
}

void App::surface_removed(uint32_t surface_id) {
   DB("surface_id is " << surface_id);
}

//  _     _           _ _                            _   _                 _
// | |__ (_)_ __   __| (_)_ __   __ _     __ _ _ __ (_) (_)_ __ ___  _ __ | |
// | '_ \| | '_ \ / _` | | '_ \ / _` |   / _` | '_ \| | | | '_ ` _ \| '_ \| |
// | |_) | | | | | (_| | | | | | (_| |  | (_| | |_) | | | | | | | | | |_) | |
// |_.__/|_|_| |_|\__,_|_|_| |_|\__, |___\__,_| .__/|_| |_|_| |_| |_| .__/|_|
//                              |___/_____|   |_|                   |_|
binding_api::result_type binding_api::register_surface(uint32_t appid,
                                                       uint32_t surfid) {
   logdebug("%s appid %u surfid %u", __func__, appid, surfid);
   if (appid > 0xff) {
      return Err<json_object *>("invalid appid");
   }

   if (surfid > 0xffff) {
      return Err<json_object *>("invalid surfaceid");
   }

   return Ok(json_object_new_int((appid << 16) + surfid));
}

binding_api::result_type binding_api::debug_layers() {
   logdebug("%s", __func__);
   return Ok(to_json(this->app->controller->lprops));
}

binding_api::result_type binding_api::debug_surfaces() {
   logdebug("%s", __func__);
   return Ok(to_json(this->app->controller->sprops));
}

binding_api::result_type binding_api::debug_status() {
   logdebug("%s", __func__);
   json_object *jr = json_object_new_object();
   json_object_object_add(jr, "surfaces",
                          to_json(this->app->controller->sprops));
   json_object_object_add(jr, "layers", to_json(this->app->controller->lprops));
   return Ok(jr);
}

binding_api::result_type binding_api::debug_terminate() {
   logdebug("%s", __func__);
   raise(SIGKILL);  // XXX afb-daemon kills it's pgroup using TERM, which
                    // doesn't play well with perf
   return Ok(json_object_new_object());
}

//                  _             _ _            _                 _
//   ___ ___  _ __ | |_ _ __ ___ | | | ___ _ __ | |__   ___   ___ | | _____
//  / __/ _ \| '_ \| __| '__/ _ \| | |/ _ \ '__|| '_ \ / _ \ / _ \| |/ / __|
// | (_| (_) | | | | |_| | | (_) | | |  __/ |   | | | | (_) | (_) |   <\__ \
//  \___\___/|_| |_|\__|_|  \___/|_|_|\___|_|___|_| |_|\___/ \___/|_|\_\___/
//                                         |_____|
void controller_hooks::surface_created(uint32_t surface_id) {
   this->app->surface_created(surface_id);
}

void controller_hooks::surface_removed(uint32_t surface_id) {
   this->app->surface_removed(surface_id);
}

}  // namespace wm