#include <cstdint>

#include "graphic.hpp"
#include "coordinates.hpp"
#include "font.hpp"
#include "start_size.hpp"
#include "control.hpp"
#include "number.hpp"

#include "pokemon_instance.hpp"

struct dialog_border {
  static constexpr uint8_t corner_top_left  = 105;
  static constexpr uint8_t corner_top_right = 106;
  static constexpr uint8_t corner_bottom_left  = 107;
  static constexpr uint8_t corner_bottom_right = 108;
  static constexpr uint8_t vertical_end_cap = 109;
  static constexpr uint8_t vertical         = 110;
  static constexpr uint8_t horizontal       = 111;
};

struct battle_border {
  static constexpr uint8_t horizontal       = 96;
  static constexpr uint8_t corner_bottom_right = 97;
  static constexpr uint8_t arrow_right      = 98;
  static constexpr uint8_t vertical         = 99;
  static constexpr uint8_t corner_bottom_left  = 100;
  static constexpr uint8_t three_dots       = 101;
  static constexpr uint8_t vertical_end_cap = 102;
  static constexpr uint8_t level            = 103;
  static constexpr uint8_t arrow_left       = 104;
};

struct hp_bar {
  static constexpr uint8_t hp   = 0x50;
  static constexpr uint8_t start_cap = 0x51;
  static constexpr uint8_t seg0 = 0x52;
  static constexpr uint8_t seg1 = 0x53;
  static constexpr uint8_t seg2 = 0x54;
  static constexpr uint8_t seg3 = 0x55;
  static constexpr uint8_t seg4 = 0x56;
  static constexpr uint8_t seg5 = 0x57;
  static constexpr uint8_t seg6 = 0x58;
  static constexpr uint8_t seg7 = 0x59;
  static constexpr uint8_t seg8 = 0x5a;
  static constexpr uint8_t end_cap_nobar = 0x5b;
  static constexpr uint8_t end_cap_bar   = 0x66;
};

struct stats {
  static constexpr uint8_t id            = 0x70; // ID
  static constexpr uint8_t no            = 0x71; // No
  static constexpr uint8_t no_dot        = 0x4e; // .
};

#define S reinterpret_cast<const uint8_t *>

void draw_text(const uint32_t base_pattern,
	       const uint8_t * text,
	       const int32_t x, const int32_t y)
{
  uint8_t i = 0, x_o = 0;
  uint8_t c;

  auto draw_ligature = [&](const uint8_t * l_text)
  {
    uint8_t j = 0;
    uint8_t d;
    while ((d = l_text[j++]) != 0)
      put_char(base_pattern, x + x_o++, y, ascii_to_font(d));
  };
  while ((c = text[i++]) != 0) {
    switch (c) {
    case ligatures_t::pkmn:
      {
	static const uint8_t * pkmn = S("\xb2\xb3");
	draw_ligature(pkmn);
      }
      break;
    case ligatures_t::poke:
      {
	static const uint8_t * poke = S("POK\xe9");
	draw_ligature(poke);
      }
      break;
    case ligatures_t::trainer:
      {
	static const uint8_t * trainer = S("TRAINER");
	draw_ligature(trainer);
      }
      break;
    default:
      put_char(base_pattern, x + x_o++, y, ascii_to_font(c));
      break;
    }
  }
}

#undef S

void draw_box_border(const uint32_t base_pattern,
		     const screen_cell_t& top_left, const screen_cell_t& bottom_right)
{
  // place corners
  put_char(base_pattern, top_left.x,  top_left.y,  dialog_border::corner_top_left);
  put_char(base_pattern, bottom_right.x, top_left.y,  dialog_border::corner_top_right);
  put_char(base_pattern, bottom_right.x, bottom_right.y, dialog_border::corner_bottom_right);
  put_char(base_pattern, top_left.x,  bottom_right.y, dialog_border::corner_bottom_left);

  for (int32_t y = top_left.y + 1; y < bottom_right.y; y++) {
    // left vertical bar
    put_char(base_pattern, top_left.x, y, dialog_border::vertical);
    // right vertical bar
    put_char(base_pattern, bottom_right.x, y, dialog_border::vertical);
  }


  for (int32_t x = top_left.x + 1; x < bottom_right.x; x++) {
    // top horizontal bar
    put_char(base_pattern, x, top_left.y, dialog_border::horizontal);

    // bottom horizontal bar
    put_char(base_pattern, x, bottom_right.y, dialog_border::horizontal);
  }
}

void draw_box_background(const uint32_t base_pattern,
			 const screen_cell_t& top_left, const screen_cell_t& bottom_right)
{
  for (int32_t x = top_left.x + 1; x < bottom_right.x; x++) {
    for (int32_t y = top_left.y + 1; y < bottom_right.y; y++) {
      put_char(base_pattern, x, y, ascii_to_font(' '));
    }
  }
}

void draw_battle_border(const uint32_t base_pattern,
			const screen_cell_t& top_corner, const screen_cell_t& bottom_corner)
{
  // draw the vertical line
  for (int32_t y = top_corner.y; y < bottom_corner.y; y++)
    put_char(base_pattern, top_corner.x, y, battle_border::vertical);

  // decide which direction we are drawing
  const int32_t increment = bottom_corner.x <= top_corner.x ? 1 : -1;

  // draw the horizontal line
  for (int32_t x = bottom_corner.x + increment; x != top_corner.x; x += increment)
    put_char(base_pattern, x, bottom_corner.y, battle_border::horizontal);

  // draw the end cap and corner piece
  const uint8_t end_cap = increment == 1 ? battle_border::arrow_left
                                         : battle_border::arrow_right;
  const uint8_t corner  = increment == 1 ? battle_border::corner_bottom_right
                                         : battle_border::corner_bottom_left;
  put_char(base_pattern, bottom_corner.x, bottom_corner.y, end_cap);
  put_char(base_pattern, top_corner.x   , bottom_corner.y, corner );
}

constexpr inline uint8_t hp_seg(const int32_t hp_48, const int32_t ix)
{
  const int32_t hp_ix = hp_48 - (ix * 8);

  if (hp_ix < 0) return hp_bar::seg0;

  switch (hp_ix) {
  default: [[fallthrough]];
  case 8: return hp_bar::seg8;
  case 7: return hp_bar::seg7;
  case 6: return hp_bar::seg6;
  case 5: return hp_bar::seg5;
  case 4: return hp_bar::seg4;
  case 3: return hp_bar::seg3;
  case 2: return hp_bar::seg2;
  case 1: return hp_bar::seg1;
  case 0: return hp_bar::seg0;
  }
}

void draw_hp_bar(const uint32_t base_pattern,
		 const screen_cell_t& top_left,
		 const uint8_t end_cap,
		 const int32_t hp_48)
{
  put_char(base_pattern, top_left.x + 0, top_left.y, hp_bar::hp);
  put_char(base_pattern, top_left.x + 1, top_left.y, hp_bar::start_cap);

  for (int32_t ix = 0; ix < 6; ix++) {
    const uint8_t seg = hp_seg(hp_48, ix);
    put_char(base_pattern, top_left.x + 2 + ix, top_left.y, seg);
  }

  put_char(base_pattern, top_left.x + 8, top_left.y, end_cap);
}

void draw_stats1(const uint32_t base_pattern,
		 const pokemon_instance_t& pokemon_instance)
{
  // white out the entire screen
  draw_box_background(base_pattern, {-1, -1}, {20, 18});

  // top status battle box
  {
    draw_battle_border(base_pattern, {19, 1}, {8, 7});

    // hp
    {
      const int32_t hp_48 = (pokemon_instance.current_hit_points * 48) / pokemon_instance.stat_values.hit_points;
      draw_hp_bar(base_pattern, {11, 3}, hp_bar::end_cap_bar, hp_48);

      draw_number_right_align(base_pattern, {12, 4},
			      pokemon_instance.current_hit_points,
			      3, ascii_to_font(' ')); // width, fill

      put_char(base_pattern, 15, 4, ascii_to_font('/'));

      draw_number_right_align(base_pattern, {16, 4},
			      pokemon_instance.stat_values.hit_points,
			      3, ascii_to_font(' ')); // width, fill
    }

    // name
    draw_text(base_pattern, pokemon[pokemon_instance.species].name, 9, 1);

    // level
    put_char(base_pattern, 14, 2, battle_border::level);
    draw_number_left_align(base_pattern, {15, 2},
			   pokemon_instance.level,
			   3); // width

#define S reinterpret_cast<const uint8_t *>
    draw_text(base_pattern, S("STATUS/___"),  9, 6);
  }

  // bottom right border
  {
    draw_battle_border(base_pattern, {19, 9}, {12, 17});

    for (int32_t ix = 0; ix < 2; ix++) {
      draw_text(base_pattern, S("TYPE"), 10, 9 + (2 * ix));
      put_char(base_pattern, 15, 9 + (2 * ix), ascii_to_font('1' + ix));
      put_char(base_pattern, 15, 9 + (2 * ix), ascii_to_font('/'));
    }
  }

  { // bottom left dialog box
    draw_box_border(base_pattern, {0, 8}, {9, 17});

    draw_text(base_pattern, S("ATTACK"),  1, 9 + 0);
    draw_text(base_pattern, S("DEFENSE"), 1, 9 + 2);
    draw_text(base_pattern, S("SPEED"),   1, 9 + 4);
    draw_text(base_pattern, S("SPECIAL"), 1, 9 + 6);
#undef S

    draw_number_right_align(base_pattern, {6, 10 + 0},
			    pokemon_instance.stat_values.attack,
			    3, ascii_to_font(' ')); // width, fill

    draw_number_right_align(base_pattern, {6, 10 + 2},
			    pokemon_instance.stat_values.defense,
			    3, ascii_to_font(' ')); // width, fill

    draw_number_right_align(base_pattern, {6, 10 + 4},
			    pokemon_instance.stat_values.speed,
			    3, ascii_to_font(' ')); // width, fill

    draw_number_right_align(base_pattern, {6, 10 + 6},
			    pokemon_instance.stat_values.special,
			    3, ascii_to_font(' ')); // width, fill
  } // end bottom left dialog box

  // pokedex number
  {
    put_char(base_pattern, 1, 7, stats::no);
    put_char(base_pattern, 2, 7, stats::no_dot);

    const int32_t pokedex_number = static_cast<int32_t>(pokemon_instance.species) + 1;
    draw_number_right_align(base_pattern,
			    {3, 7},
			    pokedex_number,
			    3,  // width
			    ascii_to_font('0') // fill
			    );
  }
}

void dialog_t::draw(const uint32_t base_pattern,
		    const start_size_t& text)
{
  draw_box_border(base_pattern, top_left, bottom_right);
  draw_box_background(base_pattern, top_left, bottom_right);

  uint32_t ix = 0;
  int32_t x = top_left.x + 1;
  int32_t y = top_left.y + 2;
  // ignore C-string null terminator
  while (ix < (text.size - 1)) {
    const uint8_t c = text.start[ix];
    switch (c) {
    case control_t::text: break;
    case control_t::done: break;
    case control_t::prompt: break;
    case control_t::page: break;

    case control_t::next: [[fallthrough]];
    case control_t::line:
      while (x < bottom_right.x) {
	put_char(base_pattern, x, y, ascii_to_font(' '));
	x++;
      }
      x = top_left.x + 1;
      y += 2;
      break;
    case control_t::para: [[fallthrough]];
    case control_t::cont:
      // fixme:
      ix = text.size;
      break;
    default:
      put_char(base_pattern, x, y, ascii_to_font(c));
      x += 1;
      break;
    }
    ix++;
  }
}