#include <platform.h>
#include <kernel/config.h>
#include "items.h"

#include "study.h"

#include <kernel/curse.h>
#include <kernel/building.h>
#include <kernel/faction.h>
#include <kernel/item.h>
#include <kernel/magic.h>
#include <kernel/messages.h>
#include <kernel/move.h>
#include <kernel/order.h>
#include <kernel/plane.h>
#include <kernel/pool.h>
#include <kernel/region.h>
#include <kernel/ship.h>
#include <kernel/spell.h>
#include <kernel/unit.h>

#include <items/demonseye.h>

#include <util/attrib.h>
#include <util/parser.h>
#include <util/rand.h>

#include <assert.h>
#include <limits.h>

/* BEGIN studypotion */
#define MAXGAIN 15
static int
use_studypotion(struct unit *u, const struct item_type *itype, int amount,
  struct order *ord)
{
  if (getkeyword(u->thisorder) == K_STUDY) {
    skill_t sk;
    skill *sv;

    init_tokens(u->thisorder);
    skip_token();
    sk = get_skill(getstrtoken(), u->faction->locale);
    sv = unit_skill(u, sk);

    if (sv && sv->level > 2) {
      /* TODO: message */
    } else if (study_cost(u, sk) > 0) {
      /* TODO: message */
    } else {
      attrib *a = a_find(u->attribs, &at_learning);
      teaching_info *teach;
      if (a == NULL) {
        a = a_add(&u->attribs, a_new(&at_learning));
      }
      teach = (teaching_info *) a->data.v;
      if (amount > MAXGAIN)
        amount = MAXGAIN;
      teach->value += amount * 30;
      if (teach->value > MAXGAIN * 30) {
        teach->value = MAXGAIN * 30;
      }
      i_change(&u->items, itype, -amount);
      return 0;
    }
  }
  return EUNUSABLE;
}

/* END studypotion */

/* BEGIN speedsail */
#define SPEEDSAIL_EFFECT 1
static int
use_speedsail(struct unit *u, const struct item_type *itype, int amount,
  struct order *ord)
{
  curse *c;
  float effect;
  ship *sh = u->ship;
  if (!sh) {
    cmistake(u, ord, 20, MSG_MOVE);
    return -1;
  }

  effect = SPEEDSAIL_EFFECT;
  c =
    create_curse(u, &sh->attribs, ct_find("shipspeedup"), 20, INT_MAX, effect,
    0);
  c_setflag(c, CURSE_NOAGE);

  ADDMSG(&u->faction->msgs, msg_message("use_speedsail", "unit speed", u,
      SPEEDSAIL_EFFECT));
  use_pooled(u, itype->rtype, GET_DEFAULT, 1);

  return 0;
}

/* END speedsail */

/* ------------------------------------------------------------- */
/* Kann auch von Nichtmagiern benutzt werden, erzeugt eine
* Antimagiezone, die zwei Runden bestehen bleibt */
static int
use_antimagiccrystal(unit * u, const struct item_type *itype, int amount,
  struct order *ord)
{
  region *r = u->region;
  const resource_type *rt_crystal = NULL;
  int i;

  if (rt_crystal == NULL) {
    rt_crystal = rt_find("antimagic");
    assert(rt_crystal != NULL);
  }
  for (i = 0; i != amount; ++i) {
    int effect, duration = 2;
    float force;
    spell *sp = find_spell("antimagiczone");
    attrib **ap = &r->attribs;
    unused_arg(ord);
    assert(sp);

    /* Reduziert die Stärke jedes Spruchs um effect */
    effect = 5;

    /* Hält Sprüche bis zu einem summierten Gesamtlevel von power aus.
     * Jeder Zauber reduziert die 'Lebenskraft' (vigour) der Antimagiezone
     * um seine Stufe */
    force = (float)effect * 20;     /* Stufe 5 =~ 100 */

    /* Regionszauber auflösen */
    while (*ap && force > 0) {
      curse *c;
      attrib *a = *ap;
      if (!fval(a->type, ATF_CURSE)) {
        do {
          ap = &(*ap)->next;
        } while (*ap && a->type == (*ap)->type);
        continue;
      }
      c = (curse *) a->data.v;

      /* Immunität prüfen */
      if (c_flags(c) & CURSE_IMMUNE) {
        do {
          ap = &(*ap)->next;
        } while (*ap && a->type == (*ap)->type);
        continue;
      }

      force = destr_curse(c, effect, force);
      if (c->vigour <= 0) {
        a_remove(&r->attribs, a);
      }
      if (*ap)
        ap = &(*ap)->next;
    }

    if (force > 0) {
      create_curse(u, &r->attribs, ct_find("antimagiczone"), (float)force, duration,
        (float)effect, 0);
    }
  }
  use_pooled(u, rt_crystal, GET_DEFAULT, amount);
  ADDMSG(&u->faction->msgs, msg_message("use_antimagiccrystal",
      "unit region", u, r));
  return 0;
}

static int
use_instantartsculpture(struct unit *u, const struct item_type *itype,
  int amount, struct order *ord)
{
  building *b;

  if (u->region->land == NULL) {
    ADDMSG(&u->faction->msgs, msg_feedback(u, ord, "error_onlandonly", ""));
    return -1;
  }

  b = new_building(bt_find("artsculpture"), u->region, u->faction->locale);
  b->size = 100;

  ADDMSG(&u->region->msgs, msg_message("artsculpture_create", "unit region",
      u, u->region));

  use_pooled(u, itype->rtype, GET_DEFAULT, 1);

  return 0;
}

static int
use_instantartacademy(struct unit *u, const struct item_type *itype,
  int amount, struct order *ord)
{
  building *b;

  if (u->region->land == NULL) {
    ADDMSG(&u->faction->msgs, msg_feedback(u, ord, "error_onlandonly", ""));
    return -1;
  }

  b = new_building(bt_find("artacademy"), u->region, u->faction->locale);
  b->size = 100;

  ADDMSG(&u->region->msgs, msg_message("artacademy_create", "unit region", u,
      u->region));

  use_pooled(u, itype->rtype, GET_DEFAULT, 1);

  return 0;
}

#define BAGPIPEFRACTION dice_rand("2d4+2")
#define BAGPIPEDURATION dice_rand("2d10+4")

static int
use_bagpipeoffear(struct unit *u, const struct item_type *itype,
  int amount, struct order *ord)
{
  int money;

  if (get_curse(u->region->attribs, ct_find("depression"))) {
    cmistake(u, ord, 58, MSG_MAGIC);
    return -1;
  }

  money = entertainmoney(u->region) / BAGPIPEFRACTION;
  change_money(u, money);
  rsetmoney(u->region, rmoney(u->region) - money);

  create_curse(u, &u->region->attribs, ct_find("depression"),
    20, BAGPIPEDURATION, 0.0, 0);

  ADDMSG(&u->faction->msgs, msg_message("bagpipeoffear_faction",
      "unit region command money", u, u->region, ord, money));

  ADDMSG(&u->region->msgs, msg_message("bagpipeoffear_region",
      "unit money", u, money));

  return 0;
}

static int
use_aurapotion50(struct unit *u, const struct item_type *itype,
  int amount, struct order *ord)
{
  if (!is_mage(u)) {
    cmistake(u, ord, 214, MSG_MAGIC);
    return -1;
  }

  change_spellpoints(u, 50);

  ADDMSG(&u->faction->msgs, msg_message("aurapotion50",
      "unit region command", u, u->region, ord));

  use_pooled(u, itype->rtype, GET_DEFAULT, 1);

  return 0;
}

void register_itemfunctions(void)
{
  register_demonseye();
  register_item_use(use_antimagiccrystal, "use_antimagiccrystal");
  register_item_use(use_instantartsculpture, "use_instantartsculpture");
  register_item_use(use_studypotion, "use_studypotion");
  register_item_use(use_speedsail, "use_speedsail");
  register_item_use(use_instantartacademy, "use_instantartacademy");
  register_item_use(use_bagpipeoffear, "use_bagpipeoffear");
  register_item_use(use_aurapotion50, "use_aurapotion50");
}