#include "dclient/widgets/inventory.h"
#include "dclient/render_glyph.h"

#include "deliantra/data/constants.h"
#include "deliantra/data/glyph.h"
#include "deliantra/data/item.h"

#include "adt/slice.h"

#include <ndk++/pen.hh>

#include <algorithm>
#include <cassert>
#include <cstring>

static char const indices[] = " 123456789abcdefghijklmnopqrstuvwxyz";
static __attribute__ ((__const__)) int maxidx () { return sizeof indices - 2; }

inventory_widget::inventory_widget (ndk::panel *parent)
  : frame ("inventory", parent)
  , inv (nullptr)
  , at (0)
{
  events ()->on_keyboard (slot (&inventory_widget::at_keyboard, this));
}

int __attribute__ ((__pure__))
inventory_widget::maxinv () const
{
  return std::min (height () - 2, maxidx ());
}

void
inventory_widget::update (std::vector<data::item> const &items, std::string const &title)
{
  inv = &items;
  set_title (title);

  int const inv_size = inv->size ();
  if (at > inv_size - 2)
    at = std::max (inv_size - 2, 0);
}

void
inventory_widget::draw ()
{
  frame::draw ();

  if (!inv || inv->empty ())
    return;

  ndk::pen pen (*this);

  int i = 0;
  for (data::item const &item : slice (*inv, at))
    {
      ++i;
      pen.move (1, i);

      // previous page
      if (at > 0 && i == 1)
        {
          pen.write ("%c: more…", indices[i]);
          continue;
        }

      // next page
      if (i >= maxinv ())
        {
          pen.write ("%c: more…", indices[i]);
          break;
        }

      pen.write ("%c: [", indices[i]);
      write (pen, data::glyphs[item.face]);
      pen.write ("] ");

      if (item.nrof < 2)
        pen.write (item.singular);
      else
        pen.write ("%d %s", item.nrof, item.plural.c_str ());

      if (item.flags & F_OPEN)    pen.write (" (open)");
      if (item.flags & F_APPLIED) pen.write (" (applied)");
      if (item.flags & F_UNPAID)  pen.write (" (unpaid)");
      if (item.flags & F_MAGIC)   pen.write (" (magic)");
      if (item.flags & F_CURSED)  pen.write (" (cursed)");
      if (item.flags & F_DAMNED)  pen.write (" (damned)");
      if (item.flags & F_LOCKED)  pen.write (" *");
    }
}

ndk::event::result
inventory_widget::at_keyboard (ndk::keyboard const &ev)
{
  if (!inv)
    return ndk::event::ignored;

  int const inv_size = inv->size ();

  switch (ev.code ())
    {
    case ndk::key::up:
      if (at > 0)
        --at;
      break;

    case ndk::key::down:
      if (at < inv_size - 2)
        ++at;
      break;

    case ndk::key::pg_up:
up:   at -= std::min (maxinv () - 2, int (at));
      break;

    case ndk::key::pg_dn:
down: at += std::min (maxinv () - 2, inv_size - at - 2);
      break;

    default:
      if (char const *const iptr = std::strchr (indices, int (ev.code ())))
        {
          int const index = iptr - indices;
          if (index > maxinv () || at + index > inv_size)
            return ndk::event::ignored;

          if (index == 1)
            goto up;

          if (index == maxinv ())
            goto down;
        }
      return ndk::event::ignored;
    }

  draw ();

  return ndk::event::accepted;
}