#include <platform.h>
#include <curses.h>

#include "bind_gmtool.h"
#include "gmtool.h"
#include "gmtool_structs.h"

#include <kernel/region.h>
#include <kernel/terrain.h>
#include <modules/autoseed.h>
#include <util/log.h>

#include <tolua.h>

#include <string.h>

static int tolua_run_mapper(lua_State * L)
{
  run_mapper();
  return 0;
}

static int tolua_highlight_region(lua_State * L)
{
  region *r = (region *)tolua_tousertype(L, 1, 0);
  int select = tolua_toboolean(L, 2, 0);
  highlight_region(r, select);
  return 0;
}

static int tolua_current_region(lua_State * L)
{
  map_region *mr =
    cursor_region(&current_state->display, &current_state->cursor);
  tolua_pushusertype(L, mr ? mr->r : NULL, TOLUA_CAST "region");
  return 1;
}

static int tolua_select_coordinate(lua_State * L)
{
  int nx = (int)tolua_tonumber(L, 1, 0);
  int ny = (int)tolua_tonumber(L, 2, 0);
  int select = tolua_toboolean(L, 3, 0);
  if (current_state) {
    select_coordinate(current_state->selected, nx, ny, select);
  }
  return 0;
}

static int tolua_select_region(lua_State * L)
{
  region *r = tolua_tousertype(L, 1, 0);
  int select = tolua_toboolean(L, 2, 0);
  if (current_state && r) {
    select_coordinate(current_state->selected, r->x, r->y, select);
  }
  return 0;
}

typedef struct tag_iterator {
  selection *list;
  tag *node;
  region *r;
  int hash;
} tag_iterator;

void tag_advance(tag_iterator * iter)
{
  while (iter->hash != MAXTHASH) {
    if (iter->node) {
      iter->node = iter->node->nexthash;
    }
    while (!iter->node && iter->hash != MAXTHASH) {
      if (++iter->hash != MAXTHASH) {
        iter->node = iter->list->tags[iter->hash];
      }
    }
    if (iter->node) {
      iter->r = findregion(iter->node->coord.x, iter->node->coord.y);
      if (iter->r) {
        break;
      }
    }
  }
}

void tag_rewind(tag_iterator * iter)
{
  if (iter->list) {
    iter->r = NULL;
    iter->node = iter->list->tags[0];
    iter->hash = 0;
    if (iter->node) {
      iter->r = findregion(iter->node->coord.x, iter->node->coord.y);
    }
    if (!iter->r) {
      tag_advance(iter);
    }
  } else {
    iter->node = 0;
    iter->hash = MAXTHASH;
  }
}

static int tolua_tags_next(lua_State * L)
{
  tag_iterator *iter = (tag_iterator *) lua_touserdata(L, lua_upvalueindex(1));
  if (iter->node) {
    tolua_pushusertype(L, (void *)iter->r, TOLUA_CAST "region");
    tag_advance(iter);
    return 1;
  } else {
    return 0;                   /* no more values to return */
  }
}

static int tolua_selected_regions(lua_State * L)
{
  tag_iterator *iter =
    (tag_iterator *) lua_newuserdata(L, sizeof(tag_iterator));

  luaL_getmetatable(L, "tag_iterator");
  lua_setmetatable(L, -2);

  iter->list = current_state->selected;
  tag_rewind(iter);

  lua_pushcclosure(L, tolua_tags_next, 1);
  return 1;
}

static int tolua_state_open(lua_State * L)
{
  unused_arg(L);
  state_open();
  return 0;
}

static int tolua_state_close(lua_State * L)
{
  unused_arg(L);
  state_close(current_state);
  return 0;
}

static int tolua_make_island(lua_State * L)
{
  int x = (int)tolua_tonumber(L, 1, 0);
  int y = (int)tolua_tonumber(L, 2, 0);
  int s = (int)tolua_tonumber(L, 3, 0);
  int n = (int)tolua_tonumber(L, 4, s / 3);

  n = build_island_e3(x, y, n, s);
  tolua_pushnumber(L, n);
  return 1;
}

static int paint_handle;
static struct lua_State *paint_state;

static void lua_paint_info(struct window *wnd, const struct state *st)
{
  struct lua_State *L = paint_state;
  int nx = st->cursor.x, ny = st->cursor.y;
  pnormalize(&nx, &ny, st->cursor.pl);
  lua_rawgeti(L, LUA_REGISTRYINDEX, paint_handle);
  tolua_pushnumber(L, nx);
  tolua_pushnumber(L, ny);
  if (lua_pcall(L, 2, 1, 0) != 0) {
    const char *error = lua_tostring(L, -1);
    log_error("paint function failed: %s\n", error);
    lua_pop(L, 1);
    tolua_error(L, TOLUA_CAST "event handler call failed", NULL);
  } else {
    const char *result = lua_tostring(L, -1);
    WINDOW *win = wnd->handle;
    int size = getmaxx(win) - 2;
    int line = 0, maxline = getmaxy(win) - 2;
    const char *str = result;
    wxborder(win);

    while (*str && line < maxline) {
      const char *end = strchr(str, '\n');
      if (!end)
        break;
      else {
        size_t len = end - str;
        int bytes = _min((int)len, size);
        mvwaddnstr(win, line++, 1, str, bytes);
        wclrtoeol(win);
        str = end + 1;
      }
    }
  }
}

static int tolua_set_display(lua_State * L)
{
  int type = lua_type(L, 1);
  if (type == LUA_TFUNCTION) {
    lua_pushvalue(L, 1);
    paint_handle = luaL_ref(L, LUA_REGISTRYINDEX);
    paint_state = L;

    set_info_function(&lua_paint_info);
  } else {
    set_info_function(NULL);
  }
  return 0;
}

static int tolua_make_block(lua_State * L)
{
  int x = (int)tolua_tonumber(L, 1, 0);
  int y = (int)tolua_tonumber(L, 2, 0);
  int r = (int)tolua_tonumber(L, 3, 6);
  const char *str = tolua_tostring(L, 4, TOLUA_CAST "ocean");
  const struct terrain_type *ter = get_terrain(str);

  make_block(x, y, r, ter);
  return 0;
}

void tolua_gmtool_open(lua_State * L)
{
  /* register user types */
  tolua_usertype(L, TOLUA_CAST "tag_iterator");

  tolua_module(L, NULL, 0);
  tolua_beginmodule(L, NULL);
  {
    tolua_module(L, TOLUA_CAST "gmtool", 0);
    tolua_beginmodule(L, TOLUA_CAST "gmtool");
    {
      tolua_function(L, TOLUA_CAST "open", &tolua_state_open);
      tolua_function(L, TOLUA_CAST "close", &tolua_state_close);

      tolua_function(L, TOLUA_CAST "editor", &tolua_run_mapper);
      tolua_function(L, TOLUA_CAST "get_selection", &tolua_selected_regions);
      tolua_function(L, TOLUA_CAST "get_cursor", &tolua_current_region);
      tolua_function(L, TOLUA_CAST "highlight", &tolua_highlight_region);
      tolua_function(L, TOLUA_CAST "select", &tolua_select_region);
      tolua_function(L, TOLUA_CAST "select_at", &tolua_select_coordinate);
      tolua_function(L, TOLUA_CAST "set_display", &tolua_set_display);

      tolua_function(L, TOLUA_CAST "make_block", &tolua_make_block);
      tolua_function(L, TOLUA_CAST "make_island", &tolua_make_island);
    }
    tolua_endmodule(L);
  }
  tolua_endmodule(L);
}