/* vi: set ts=2:
+-------------------+
|                   |  Enno Rehling <enno@eressea.de>
| Eressea PBEM host |  Christian Schlittchen <corwin@amber.kn-bremen.de>
| (c) 1998 - 2010   |  Katja Zedel <katze@felidae.kn-bremen.de>
|                   |  Henning Peters <faroul@beyond.kn-bremen.de>
+-------------------+

This program may not be used, modified or distributed
without prior permission by the authors of Eressea.
*/

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

#include <kernel/unit.h>
#include <kernel/faction.h>
#include <kernel/ship.h>
#include <kernel/building.h>
#include <kernel/region.h>
#include <kernel/objtypes.h>
#include <util/attrib.h>
#include <util/log.h>
#include <util/resolve.h>

#include <storage.h>

/* external libraries */
#include <bson.h>

#include <lua.h>
#include <tolua.h>
#include <errno.h>

static void init_ext(attrib * a)
{
  lua_State *L = (lua_State *) global.vm_state;

  lua_pushstring(L, "callbacks");
  lua_rawget(L, LUA_GLOBALSINDEX);
  if (lua_istable(L, -1)) {
    lua_pushstring(L, "attrib_init");
    lua_rawget(L, LUA_GLOBALSINDEX);
    if (lua_isfunction(L, -1)) {
      lua_rawgeti(L, LUA_REGISTRYINDEX, a->data.i);
      if (lua_pcall(L, 1, 0, 0) != 0) {
        const char *error = lua_tostring(L, -1);
        log_error("attrib_init '%d': %s.\n", a->data.i, error);
      }
    }
  }
}

static void free_ext(attrib * a)
{
  lua_State *L = (lua_State *) global.vm_state;
  if (a->data.i > 0) {
    luaL_unref(L, LUA_REGISTRYINDEX, a->data.i);
  }
}

static int age_ext(attrib * a)
{
  return AT_AGE_KEEP;
}

static void write_ext_i(lua_State * L, const char *name, bson_buffer * bb)
{
  int type = lua_type(L, -1);
  switch (type) {
    case LUA_TNUMBER:
    {
      double value = tolua_tonumber(L, -1, 0);
      bson_append_double(bb, name, value);
    }
      break;
    case LUA_TSTRING:
    {
      const char *value = tolua_tostring(L, -1, 0);
      bson_append_string(bb, name, value);
    }
      break;
    case LUA_TTABLE:
    {
      int n = luaL_getn(L, -1);
      if (n) {
        bson_buffer *arr = bson_append_start_array(bb, name);
        int i;
        for (i = 0; i != n; ++i) {
          char num[12];
          bson_numstr(num, i);
          lua_rawgeti(L, -1, i + 1);
          write_ext_i(L, num, arr);
          lua_pop(L, 1);
        }
        bson_append_finish_object(arr);
      } else {
        bson_buffer *sub = bson_append_start_object(bb, name);
        lua_pushnil(L);         /* first key */
        while (lua_next(L, -2) != 0) {
          const char *key;
          /* uses 'key' (at index -2) and 'value' (at index -1) */
          lua_pushvalue(L, -2);
          key = lua_tolstring(L, -1, 0);
          lua_pushvalue(L, -2);
          if (key) {
            write_ext_i(L, key, sub);
          }
          /* removes 'value'; keeps 'key' for next iteration */
          lua_pop(L, 3);
        }
        bson_append_finish_object(sub);
      }
    }
      break;
    case LUA_TUSERDATA:
    {
      tolua_Error tolua_err;
      if (tolua_isusertype(L, -1, "unit", 0, &tolua_err)) {
        unit *u = (unit *) tolua_tousertype(L, -1, 0);
        bson_oid_t oid;
        oid.ints[0] = TYP_UNIT;
        oid.ints[1] = u->no;
        bson_append_oid(bb, name, &oid);
      } else if (tolua_isusertype(L, -1, "region", 0, &tolua_err)) {
        region *r = (region *) tolua_tousertype(L, -1, 0);
        bson_oid_t oid;
        oid.ints[0] = TYP_REGION;
        oid.ints[1] = r->uid;
        bson_append_oid(bb, name, &oid);
      } else if (tolua_isusertype(L, -1, "ship", 0, &tolua_err)) {
        ship *sh = (ship *) tolua_tousertype(L, -1, 0);
        bson_oid_t oid;
        oid.ints[0] = TYP_SHIP;
        oid.ints[1] = sh->no;
        bson_append_oid(bb, name, &oid);
      } else if (tolua_isusertype(L, -1, "building", 0, &tolua_err)) {
        building *b = (building *) tolua_tousertype(L, -1, 0);
        bson_oid_t oid;
        oid.ints[0] = TYP_BUILDING;
        oid.ints[1] = b->no;
        bson_append_oid(bb, name, &oid);
      } else {
        log_error("unsuported type.\n");
        bson_append_null(bb, name);
      }
    }
      break;
    default:
      bson_append_null(bb, name);
      break;
  }
}

static void
write_ext(const attrib * a, const void *owner, struct storage *store)
{
  lua_State *L = (lua_State *) global.vm_state;
  if (a->data.i > 0) {
    int handle = a->data.i;
    bson_buffer bb;
    bson b;

    bson_buffer_init(&bb);
    lua_rawgeti(L, LUA_REGISTRYINDEX, handle);
    write_ext_i(L, "_data", &bb);
    bson_from_buffer(&b, &bb);
    store->w_int(store, bson_size(&b));
    store->w_bin(store, b.data, bson_size(&b));
    bson_destroy(&b);
  }
}

static int read_ext_i(lua_State * L, bson_iterator * it, bson_type type)
{
  switch (type) {
    case bson_double:
    {
      lua_pushnumber(L, bson_iterator_double(it));
    }
      break;
    case bson_string:
    {
      lua_pushstring(L, bson_iterator_string(it));
    }
      break;
    case bson_array:
    {
      bson_iterator sub;
      int err;
      bson_iterator_subiterator(it, &sub);
      lua_newtable(L);
      if (bson_iterator_more(&sub)) {
        bson_type ctype;
        for (ctype = bson_iterator_next(&sub); bson_iterator_more(&sub);
          ctype = bson_iterator_next(&sub)) {
          int i = atoi(bson_iterator_key(&sub));
          err = read_ext_i(L, &sub, ctype);
          if (err) {
            lua_pop(L, 1);
            return err;
          }
          lua_rawseti(L, -2, i + 1);
        }
      }
    }
      break;
    case bson_object:
    {
      bson_iterator sub;
      int err;
      bson_iterator_subiterator(it, &sub);
      lua_newtable(L);
      if (bson_iterator_more(&sub)) {
        bson_type ctype;
        for (ctype = bson_iterator_next(&sub); bson_iterator_more(&sub);
          ctype = bson_iterator_next(&sub)) {
          lua_pushstring(L, bson_iterator_key(&sub));
          err = read_ext_i(L, &sub, ctype);
          if (err) {
            lua_pop(L, 1);
            return err;
          }
          lua_rawset(L, -3);
        }
      }
    }
      break;
    case bson_oid:
    {
      bson_oid_t *oid = bson_iterator_oid(it);
      if (oid->ints[0] == TYP_UNIT) {
        unit *u = findunit(oid->ints[1]);
        if (u)
          tolua_pushusertype(L, u, "unit");
        else
          lua_pushnil(L);
      } else if (oid->ints[0] == TYP_REGION) {
        region *r = findregionbyid(oid->ints[1]);
        if (r)
          tolua_pushusertype(L, r, "region");
        else
          lua_pushnil(L);
      } else if (oid->ints[0] == TYP_SHIP) {
        ship *sh = findship(oid->ints[1]);
        if (sh)
          tolua_pushusertype(L, sh, "ship");
        else
          lua_pushnil(L);
      } else if (oid->ints[0] == TYP_BUILDING) {
        building *b = findbuilding(oid->ints[1]);
        if (b)
          tolua_pushusertype(L, b, "building");
        else
          lua_pushnil(L);
      } else {
        log_error("unknown oid %d %d %d\n", oid->ints[0], oid->ints[1], oid->ints[2]);
        lua_pushnil(L);
      }
    }
      break;
    case bson_null:
      lua_pushnil(L);
      break;
    case bson_eoo:
      return EFAULT;
    default:
      return EINVAL;
  }
  return 0;
}

static int resolve_bson(variant data, void *address)
{
  lua_State *L = (lua_State *) global.vm_state;
  bson b;
  int err;
  bson_iterator it;
  attrib *a = (attrib *) address;
  char *buffer = data.v;

  bson_init(&b, buffer, 1);
  bson_iterator_init(&it, b.data);
  err = read_ext_i(L, &it, bson_iterator_next(&it));
  a->data.i = luaL_ref(L, LUA_REGISTRYINDEX);
  bson_destroy(&b);
  return err ? AT_READ_FAIL : AT_READ_OK;
}

static int read_ext(attrib * a, void *owner, struct storage *store)
{
  variant data;
  int len = store->r_int(store);
  data.v = bson_malloc(len);
  store->r_bin(store, data.v, (size_t) len);
  a->data.v = 0;
  ur_add(data, a, resolve_bson);
  return AT_READ_OK;
}

attrib_type at_lua_ext = {
  "lua", init_ext, free_ext, age_ext, write_ext, read_ext
};

static attrib **get_attribs(lua_State * L, int idx)
{
  attrib **ap = NULL;
  tolua_Error tolua_err;

  if (tolua_isusertype(L, idx, TOLUA_CAST "unit", 0, &tolua_err)) {
    unit *u = (unit *) tolua_tousertype(L, idx, 0);
    if (u)
      ap = &u->attribs;
  } else if (tolua_isusertype(L, idx, TOLUA_CAST "region", 0, &tolua_err)) {
    region *r = (region *) tolua_tousertype(L, idx, 0);
    if (r)
      ap = &r->attribs;
  } else if (tolua_isusertype(L, idx, TOLUA_CAST "faction", 0, &tolua_err)) {
    faction *f = (faction *) tolua_tousertype(L, idx, 0);
    if (f)
      ap = &f->attribs;
  } else if (lua_isstring(L, idx)) {
    const char *str = tolua_tostring(L, idx, NULL);
    if (str && strcmp(str, "global") == 0) {
      ap = &global.attribs;
    }
  }
  return ap;
}

static int tolua_attrib_create(lua_State * L)
{
  attrib **ap = get_attribs(L, 1);
  if (ap) {
    attrib *a = a_new(&at_lua_ext);
    int handle;

    lua_pushvalue(L, 2);
    handle = luaL_ref(L, LUA_REGISTRYINDEX);
    a->data.i = handle;

    a_add(ap, a);
    tolua_pushusertype(L, (void *)a, TOLUA_CAST "attrib");
    return 1;
  }
  return 0;
}

int tolua_attrib_data(lua_State * L)
{
  attrib *a = (attrib *) tolua_tousertype(L, 1, 0);
  if (a && a->data.i) {
    lua_rawgeti(L, LUA_REGISTRYINDEX, a->data.i);
    return 1;
  }
  return 0;
}

attrib *tolua_get_lua_ext(struct attrib * alist)
{
  while (alist && alist->type != &at_lua_ext)
    alist = alist->next;
  return alist;
}

int tolua_attriblist_next(lua_State * L)
{
  attrib **attrib_ptr = (attrib **) lua_touserdata(L, lua_upvalueindex(1));
  attrib *a = *attrib_ptr;
  if (a != NULL) {
    tolua_pushusertype(L, (void *)a, TOLUA_CAST "attrib");
    *attrib_ptr = tolua_get_lua_ext(a->next);
    return 1;
  } else
    return 0;                   /* no more values to return */
}

int tolua_attrib_get(lua_State * L)
{
  attrib **ap = get_attribs(L, 1);
  if (ap) {
    attrib *a = tolua_get_lua_ext(*ap);
    attrib **attrib_ptr = (attrib **) lua_newuserdata(L, sizeof(attrib *));
    luaL_getmetatable(L, "attrib");
    lua_setmetatable(L, -2);
    *attrib_ptr = a;
    lua_pushcclosure(L, tolua_attriblist_next, 1);
    return 1;
  } else
    return 0;
}

void tolua_attrib_open(lua_State * L)
{
  at_register(&at_lua_ext);

  tolua_usertype(L, TOLUA_CAST "attrib");

  tolua_module(L, NULL, 0);
  tolua_beginmodule(L, NULL);
  {
    tolua_cclass(L, TOLUA_CAST "attrib", TOLUA_CAST "attrib", TOLUA_CAST "",
      NULL);
    tolua_beginmodule(L, TOLUA_CAST "attrib");
    {
      tolua_function(L, TOLUA_CAST "create", &tolua_attrib_create);
      tolua_function(L, TOLUA_CAST "get", &tolua_attrib_get);
      tolua_variable(L, TOLUA_CAST "data", &tolua_attrib_data, NULL);
    }
    tolua_endmodule(L);
  }
  tolua_endmodule(L);
}