#include "script_system.h"
#include <iostream>
#include "game.h"
#include "message_system.h"
#include "animation_system.h"
#include "character_system.h"
#include "transform_system.h"
#include "effect_system.h"
#include "camera_system.h"
#include "vector.h"

ScriptSystem::ScriptSystem(Game& game) : game_(game) {
  engine_.open_libraries(
    sol::lib::base,
    sol::lib::coroutine,
    sol::lib::math);

  engine_.new_usertype<vec2i>(
    "vec2i",
    "x", [] (const vec2i& v) { return v.x(); },
    "y", [] (const vec2i& v) { return v.y(); });

  engine_.new_usertype<Sprite>(
    "sprite",
    "loc", &Sprite::loc,
    "dir", &Sprite::dir,
    "followers", &Sprite::followers,
    "characterState", &Sprite::characterState,
    "controllable", &Sprite::controllable,
    "animFinished", &Sprite::animFinished);

  engine_.new_usertype<MessageSystem>(
    "message",
    "displayMessage", &MessageSystem::displayMessage,
    "showChoice", &MessageSystem::showChoice,
    "displayCutsceneBars", &MessageSystem::displayCutsceneBars,
    "hideCutsceneBars", &MessageSystem::hideCutsceneBars,
    "isMessageActive", sol::property(&MessageSystem::isMessageActive),
    "getChoiceSelection", &MessageSystem::getChoiceSelection);

  engine_.new_usertype<AnimationSystem>(
    "animation",
    "initSprite", &AnimationSystem::initSprite,
    "setSpriteAnimation", &AnimationSystem::setSpriteAnimation,
    "setSpriteDirection", &AnimationSystem::setSpriteDirection);

  engine_.new_usertype<CharacterSystem>(
    "character",
    "startRunning", &CharacterSystem::startRunning,
    "halt", &CharacterSystem::halt);

  engine_.new_usertype<TransformSystem>(
    "transform",
    "initSprite", [] (TransformSystem& transform, int spriteId, int x, int y, SpriteLayer layer) {
      transform.initSprite(spriteId, vec2i{x, y}, layer);
    });

  engine_.new_usertype<EffectSystem>(
    "effect",
    "fadeScreen", &EffectSystem::fadeScreen,
    "isScreenFadeComplete", &EffectSystem::isScreenFadeComplete,
    "fadeMap", &EffectSystem::fadeMap,
    "isMapFadeComplete", &EffectSystem::isMapFadeComplete,
    "shakeCamera", &EffectSystem::shakeCamera,
    "stopShakingCamera", &EffectSystem::stopShakingCamera);

  engine_.new_usertype<CameraSystem>(
    "camera",
    "panToSprite", &CameraSystem::panToSprite,
    "isPanning", &CameraSystem::isPanning,
    "unlockCamera", &CameraSystem::unlockCamera,
    "setFollowingSprite", &CameraSystem::setFollowingSprite);

  engine_.new_usertype<Mixer>(
    "mixer",
    "playSound", &Mixer::playSound,
    "loopSound", &Mixer::loopSound,
    "stopChannel", &Mixer::stopChannel);

  engine_.set_function(
    "message",
    [&] () -> MessageSystem& {
      return game_.getSystem<MessageSystem>();
    });

  engine_.set_function(
    "animation",
    [&] () -> AnimationSystem& {
      return game_.getSystem<AnimationSystem>();
    });

  engine_.set_function(
    "character",
    [&] () -> CharacterSystem& {
      return game_.getSystem<CharacterSystem>();
    });

  engine_.set_function(
    "transform",
    [&] () -> TransformSystem& {
      return game_.getSystem<TransformSystem>();
    });

  engine_.set_function(
    "effect",
    [&] () -> EffectSystem& {
      return game_.getSystem<EffectSystem>();
    });

  engine_.set_function(
    "camera",
    [&] () -> CameraSystem& {
      return game_.getSystem<CameraSystem>();
    });

  engine_.set_function(
    "mixer",
    [&] () -> Mixer& {
      return game_.getMixer();
    });

  engine_.set_function(
    "emplaceSprite",
    [&] (std::string alias) -> int {
      return game_.emplaceSprite(alias);
    });

  engine_.set_function(
    "destroySprite",
    [&] (int spriteId) {
      game_.destroySprite(spriteId);
    });

  engine_.set_function(
    "getSpriteByAlias",
    [&] (std::string alias) -> int {
      return game_.getSpriteByAlias(alias);
    });

  engine_.set_function(
    "getPlayerSprite",
    [&] () -> int {
      for (int id : game_.getSprites()) {
        Sprite& sprite = game_.getSprite(id);
        if (sprite.player) {
          return id;
        }
      }
      return -1;
    });

  engine_.set_function(
    "getSprite",
    [&] (int id) -> Sprite& {
      return game_.getSprite(id);
    });

  engine_.set_function(
    "loadMap",
    [&] (std::string filename, std::string warpPoint, Direction dir) {
      game_.loadMap(filename, warpPoint, dir);
    });

  engine_.script_file("../res/scripts/common.lua");
}

void ScriptSystem::tick(double dt) {
  if (callable_ && *callable_) {
    auto result = (*callable_)(dt);
    if (!result.valid()) {
      sol::error e = result;
      throw e;
    }

    if (!*callable_) {
      callable_.reset();
      runner_.reset();
    }
  }
}

void ScriptSystem::runScript(std::string mapName, std::string scriptName) {
  if (!loadedScripts_.count(mapName)) {
    engine_.script_file("../res/scripts/" + mapName + ".lua");
    loadedScripts_.insert(mapName);
  }

  runner_.reset(new sol::thread(sol::thread::create(engine_.lua_state())));
  callable_.reset(new sol::coroutine(runner_->state().traverse_get<sol::function>(mapName, scriptName)));

  if (!*callable_) {
    throw std::runtime_error("Error running script: " + mapName + "." + scriptName);
  }

  auto result = (*callable_)();
  if (!result.valid()) {
    sol::error e = result;
    throw e;
  }

  if (!*callable_) {
    callable_.reset();
    runner_.reset();
  }
}