#include "dbc.hpp"
#include "ai.hpp"

namespace ai {
  using namespace nlohmann;
  using namespace dbc;

  static AIManager AIMGR;
  static bool initialized = false;

  inline void validate_profile(nlohmann::json& profile) {
    for(auto& [name_key, value] : profile.items()) {
      check(value < STATE_MAX,
        fmt::format("profile field {} has value {} greater than STATE_MAX {}", (std::string)name_key, (int)value, STATE_MAX));
    }
  }

  Action config_action(nlohmann::json& profile, nlohmann::json& config) {
    check(config.contains("name"), "config_action: action config missing name");
    check(config.contains("cost"), "config_action: action config missing cost");

    validate_profile(profile);

    Action result(config["name"], config["cost"]);

    check(config.contains("needs"),
        fmt::format("config_action: no 'needs' field", result.$name));
    check(config.contains("effects"),
        fmt::format("config_action: no 'effects' field", result.$name));

    for(auto& [name_key, value] : config["needs"].items()) {
      check(profile.contains(name_key), fmt::format("config_action: profile does not have name {}", result.$name, name_key));
      int name = profile[name_key].template get<int>();

      result.needs(name, bool(value));
    }

    for(auto& [name_key, value] : config["effects"].items()) {
      check(profile.contains(name_key), fmt::format("config_action: profile does not have name {}", result.$name, name_key));

      int name = profile[name_key].template get<int>();

      result.effect(name, bool(value));
    }

    return result;
  }

  State config_state(nlohmann::json& profile, nlohmann::json& config) {
    State result;
    validate_profile(profile);

    for(auto& [name_key, value] : config.items()) {
      check(profile.contains(name_key), fmt::format("config_state: profile does not have name {}", name_key));

      int name = profile[name_key].template get<int>();
      result[name] = bool(value);
    }

    return result;
  }

  void init(std::string config_path) {
    initialized = true;
    Config config(config_path);

    // profile specifies what keys (bitset indexes) are allowed
    // and how they map to the bitset of State
    AIMGR.profile = config["profile"];
    validate_profile(AIMGR.profile);

    // load all actions
    auto& actions = config["actions"];
    for(auto& action_vars : actions) {
      auto the_action = config_action(AIMGR.profile, action_vars);
      AIMGR.actions.insert_or_assign(the_action.$name, the_action);
    }

    // load all states
    auto& states = config["states"];
    for(auto& [name, state_vars] : states.items()) {
      auto the_state = config_state(AIMGR.profile, state_vars);
      AIMGR.states.insert_or_assign(name, the_state);
    }

    auto& scripts = config["scripts"];
    for(auto& [script_name, action_names] : scripts.items()) {
      std::vector<Action> the_script;
      for(auto name : action_names) {

        check(AIMGR.actions.contains(name),
            fmt::format("ai::init(): script {} uses action {} that doesn't exist",
              (std::string)script_name, (std::string)name));

        the_script.push_back(AIMGR.actions.at(name));
      }

      AIMGR.scripts.insert_or_assign(script_name, the_script);
    }
  }

  State load_state(std::string state_name) {
    check(initialized, "you forgot to initialize the AI first.");
    check(AIMGR.states.contains(state_name), fmt::format(
          "ai::load_state({}): state does not exist in config",
          state_name));

    return AIMGR.states.at(state_name);
  }

  Action load_action(std::string action_name) {
    check(initialized, "you forgot to initialize the AI first.");
    check(AIMGR.states.contains(action_name), fmt::format(
          "ai::load_action({}): action does not exist in config",
          action_name));
    return AIMGR.actions.at(action_name);
  }

  std::vector<Action> load_script(std::string script_name) {
    check(AIMGR.scripts.contains(script_name), fmt::format(
          "ai::load_script(): no script named {} configured", script_name));
    return AIMGR.scripts.at(script_name);
  }

  std::optional<Script> plan(std::string script_name, State start, State goal) {
    check(initialized, "you forgot to initialize the AI first.");
    auto script = load_script(script_name);
    return plan_actions(script, start, goal);
  }

  int state_id(std::string name) {
    check(AIMGR.profile.contains(name), fmt::format(
          "ai::state_id({}): id is not configured in profile",
          name));
    return AIMGR.profile.at(name);
  }
}