/*
  This file is part of ct.

  This program is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with ct. If not, see <https://www.gnu.org/licenses/>.
*/

#ifndef TAK_H
#define TAK_H

#include <stdint.h>

// ===================================================================
// Types
// ===================================================================

enum ACT_RESULT {
  ACT_OK,
  ACT_ILLEGAL,
  ACT_OVERFLOW,
  ACT_INVALID_PTN,
  GAME_END
};

enum PTN_RESULT { PTN_OK, PTN_INVALID };
enum TPS_RESULT { TPS_OK, TPS_INVALID };

enum COLOUR { C_WHITE, C_BLACK };
enum STONE_VARIANT { STONE_FLAT, STONE_STANDING, STONE_CAPSTONE };
enum MOVE_DIRECTION { M_UP, M_DOWN, M_LEFT, M_RIGHT };
enum WIN_TYPE {
  WIN_DRAW,
  WIN_FLAT_WHITE,
  WIN_FLAT_BLACK,
  WIN_ROAD_WHITE,
  WIN_ROAD_BLACK
};

typedef uint8_t data_t;
typedef uint16_t colour_stack_t;

typedef struct tak_state_s {
  data_t celldat[36];
  colour_stack_t colours[36];
  enum WIN_TYPE won;
  enum COLOUR current_colour;
  uint8_t white_count, black_count, ply, board_size;
} *tak_state_p;

#define NUM_SHIFT 4
#define NUM_MASK (0xF << NUM_SHIFT) // 0b11110000
#define NUM_INC (0x1 << NUM_SHIFT)  // 0b00010000
#define STONE_MASK 3                // 0b00000011
#define STONE_AT(state, l) (state->celldat[(l)] & STONE_MASK)
#define COUNT_AT(state, l) (state->celldat[(l)] >> NUM_SHIFT)
#define THE_COORDS(board_size, col, row) ((col) + (row)*board_size)

// ===================================================================
// Methods
// ===================================================================

tak_state_p new_tak_state(const uint8_t board_size);
void free_tak_state(tak_state_p state);

// -------------------------------------------------------------------
// Game state

void reset_state(tak_state_p state, const uint8_t new_board_size);
void next_ply(tak_state_p state);

enum ACT_RESULT try_place(tak_state_p state, const int8_t location,
                          const enum COLOUR colour,
                          const enum STONE_VARIANT stone);

enum ACT_RESULT try_move(tak_state_p state, const int8_t location,
                         const enum MOVE_DIRECTION direction,
                         const uint8_t steps, const uint8_t drops[5]);

enum WIN_TYPE check_win(tak_state_p state);

// -------------------------------------------------------------------
// PTN related

enum PTN_RESULT parse_place(const uint8_t board_size, char *in_ptn,
                            uint8_t *out_location,
                            enum STONE_VARIANT *out_stone);

enum PTN_RESULT parse_move(const uint8_t board_size, char *in_ptn,
                           uint8_t *out_location,
                           enum MOVE_DIRECTION *out_direction,
                           uint8_t *out_steps, uint8_t out_drops[5]);

void generate_place(const uint8_t board_size, const uint8_t in_location,
                    const enum STONE_VARIANT in_stone, char out_ptn[4]);

void generate_move(const uint8_t board_size, const uint8_t in_location,
                   const enum MOVE_DIRECTION in_direction,
                   const uint8_t in_steps, const uint8_t in_drops[5],
                   char out_ptn[10]);

// -------------------------------------------------------------------
// Game driver

enum ACT_RESULT do_ptn(tak_state_p state, char *ptn);
#endif