#include "raylib.h"
#include <stdlib.h>
#include <stdio.h>
#include <time.h>

#define SCREEN_WIDTH  800
#define SCREEN_HEIGHT 600

#define MATRIX_WIDTH  10
#define MATRIX_HEIGHT 40

#define BLOCK_SIZE 25

#define FALL_TICK 0.3
#define SOFT_DROP_MULT 4.0
#define LOCK_TICK 0.5

enum Phases {
    GENERATION,
    FALL,
    LOCK,
    PATTERN,
    //MARK,
    //ITERATE,
    //ANIMATE,
    //ELIMINATE,
    //COMPLETE
} game_phase;

enum InputResult {
    NONE = 0,
    MOVED,
    HARD_DROPPED
};

#include "tetromino.h"

struct {
    int pos_x;
    int pos_y;
    int rotation;
    int type;
} current_piece;

struct Color matrix[MATRIX_WIDTH][MATRIX_HEIGHT];
int piece_queue[TETROMINO_COUNT*2];
int current_bag = 0;
int current_piece_index = 0;
int hold = 7;
int held = 0;
double phase_time;
double fall_tick;

void draw_block(int x, int y, int width, int height, struct Color color)
{
    DrawRectangle(x, -y + SCREEN_HEIGHT - height, width, height, color);
}

int is_overlap(int x, int y)
{
    for (int i = 0; i < tetrominos[current_piece.type].size; i++) {
        for (int j = 0; j < tetrominos[current_piece.type].size; j++) {
            if (tetrominos[current_piece.type].directions[current_piece.rotation][j][i] == 1) {
                if (current_piece.pos_x + i - 1 + x >= MATRIX_WIDTH
                        || current_piece.pos_x + i - 1 + x < 0
                        || current_piece.pos_y + j - 1 + y < 0
                        || (!ColorIsEqual(BLACK, matrix[current_piece.pos_x + i - 1 + x][current_piece.pos_y + j - 1 + y])
                         && !ColorIsEqual(WHITE, matrix[current_piece.pos_x + i - 1 + x][current_piece.pos_y + j - 1 + y]))) {
                    return 1;
                }
            }
        }
    }
    return 0;
}

void render_matrix(void)
{
    int matrix_origin_x = (SCREEN_WIDTH/2 - (MATRIX_WIDTH * BLOCK_SIZE))/2;
    int matrix_origin_y = (SCREEN_HEIGHT - MATRIX_HEIGHT/2 * BLOCK_SIZE)/2;

    /* draw matrix background */
    draw_block(
        matrix_origin_x - 1
        ,matrix_origin_y - 1
        ,MATRIX_WIDTH * BLOCK_SIZE + 2
        ,MATRIX_HEIGHT/2 * BLOCK_SIZE + 2
        ,GRAY
    );

    /* draw matrix */
    for (int i = 0; i < MATRIX_WIDTH; i++) {
        for (int j = 0; j < MATRIX_HEIGHT; j++) {
            draw_block(
                matrix_origin_x + i * BLOCK_SIZE + 1
                ,matrix_origin_y + j * BLOCK_SIZE + 1
                ,BLOCK_SIZE - 2
                ,BLOCK_SIZE - 2
                ,matrix[i][j]
            );
        }
    }

    int ghost_y = 0;
    if (game_phase == FALL || game_phase == LOCK) {
        /* draw ghost piece */
        while(!is_overlap(0, ghost_y)) {
            ghost_y--;
        }

        for (int i = 0; i < tetrominos[current_piece.type].size; i++) {
            for (int j = 0; j < tetrominos[current_piece.type].size; j++) {
                if (tetrominos[current_piece.type].directions[current_piece.rotation][j][i] == 1) {
                    draw_block(
                        (matrix_origin_x + ((current_piece.pos_x + i - 1) * BLOCK_SIZE)) + 3
                        ,(matrix_origin_y + ((current_piece.pos_y + j + ghost_y) * BLOCK_SIZE)) + 3
                        ,BLOCK_SIZE - 6
                        ,BLOCK_SIZE - 6
                        ,tetrominos[current_piece.type].color
                    );
                    draw_block(
                        (matrix_origin_x + ((current_piece.pos_x + i - 1) * BLOCK_SIZE)) + 4
                        ,(matrix_origin_y + ((current_piece.pos_y + j + ghost_y) * BLOCK_SIZE)) + 4
                        ,BLOCK_SIZE - 8
                        ,BLOCK_SIZE - 8
                        ,BLACK
                    );
                }
            }
        }
        /* draw current piece */
        for (int i = 0; i < tetrominos[current_piece.type].size; i++) {
            for (int j = 0; j < tetrominos[current_piece.type].size; j++) {
                if (tetrominos[current_piece.type].directions[current_piece.rotation][j][i] == 1) {
                    draw_block(
                        (matrix_origin_x + ((current_piece.pos_x + i - 1) * BLOCK_SIZE)) + 1
                        ,(matrix_origin_y + ((current_piece.pos_y + j - 1) * BLOCK_SIZE)) + 1
                        ,BLOCK_SIZE - 2
                        ,BLOCK_SIZE - 2
                        ,tetrominos[current_piece.type].color
                    );
                }
            }
        }
    }


    /* draw piece hold */
    draw_block(
        SCREEN_WIDTH/2 + 1 - (BLOCK_SIZE),
        matrix_origin_y + MATRIX_HEIGHT/2 * BLOCK_SIZE - 3 * BLOCK_SIZE,
        4*BLOCK_SIZE,
        4*BLOCK_SIZE,
        BLACK
    );
    if (hold != 7) {
        for (int i = 0; i < tetrominos[hold].size; i++) {
            for (int j = 0; j < tetrominos[hold].size; j++) {
                if (tetrominos[hold].directions[NORTH][j][i] == 1) {
                    draw_block(
                        ((SCREEN_WIDTH/2 + 1 - (BLOCK_SIZE)) + (i * BLOCK_SIZE)) + 1
                               + ((hold != I && hold != O)?(BLOCK_SIZE/2):0)
                        ,matrix_origin_y + (MATRIX_HEIGHT/2 * BLOCK_SIZE) + ((j-3) * BLOCK_SIZE)
                        ,BLOCK_SIZE - 2
                        ,BLOCK_SIZE - 2
                        ,tetrominos[hold].color
                    );
                }
            }
        }
    }

    /* draw piece queue */
    draw_block(
        SCREEN_WIDTH/2 + 1 - (BLOCK_SIZE),
        matrix_origin_y + MATRIX_HEIGHT/2 * BLOCK_SIZE - 20 * BLOCK_SIZE,
        4*BLOCK_SIZE,
        (4*BLOCK_SIZE) * 4,
        BLACK
    );
    for (int y = 0; y < 4; y++) {
        for (int i = 0; i < tetrominos[piece_queue[(y+current_piece_index)%14]].size; i++) {
            for (int j = 0; j < tetrominos[piece_queue[(y+current_piece_index)%14]].size; j++) {
                if (tetrominos[piece_queue[(y+current_piece_index)%14]].directions[NORTH][j][i] == 1) {
                    draw_block(
                        ((SCREEN_WIDTH/2 + 1 - (BLOCK_SIZE)) + (i * BLOCK_SIZE)) + 1
                           + ((piece_queue[(y+current_piece_index)%14] != I && piece_queue[(y+current_piece_index)%14] != O)?(BLOCK_SIZE/2):0)
                        ,((matrix_origin_y + MATRIX_HEIGHT/2 * BLOCK_SIZE - 20 * BLOCK_SIZE) + ((j - 1) * BLOCK_SIZE)) + 1 + ((3 - y) * BLOCK_SIZE * 4) + BLOCK_SIZE/2
                        ,BLOCK_SIZE - 2
                        ,BLOCK_SIZE - 2
                        ,tetrominos[piece_queue[(y+current_piece_index)%14]].color
                    );
                }
            }
        }
    }
}

void shuffle_bag(int *bag)
{
    for (int i = 0; i < TETROMINO_COUNT; i++) {
        bag[i] = i;
    }
    for (int i = 0; i < TETROMINO_COUNT; i++) {
        int r = i + rand() / (RAND_MAX / (TETROMINO_COUNT - i) + 1);
        int t = bag[r];
        bag[r] = bag[i];
        bag[i] = t;
    }
}

void generation_phase(void)
{
    if (phase_time < 0.2) {
        return;
    }
    // bag generation
    if (current_piece_index == 14) {
        shuffle_bag(&(piece_queue[7]));
        current_piece_index = 0;
    }
    if (current_piece_index == 7) {
        shuffle_bag(piece_queue);
    }

    // set current piece
    current_piece.type = piece_queue[current_piece_index++];
    current_piece.rotation = NORTH;
    current_piece.pos_x = 4;
    current_piece.pos_y = 20;
    held = 0;
    phase_time = 0.0;
    game_phase = FALL;
}

int rotate_piece(int dir)
{
    int *kick_table;
    int i;
    int can_rotate = 0;

    if (dir == 1) {
        kick_table = tetrominos[current_piece.type].cw_kick_table[current_piece.rotation];
    } else if (dir == -1) {
        kick_table = tetrominos[current_piece.type].ccw_kick_table[current_piece.rotation];
    }

    current_piece.rotation += dir;
    if (current_piece.rotation < 0) {
        current_piece.rotation = 3;
    } else {
        current_piece.rotation = current_piece.rotation % 4;
    }

    for (i = 0; i < 10 && !can_rotate; i += 2) {
        if (!is_overlap(kick_table[i], kick_table[i+1])) {
            current_piece.pos_x += kick_table[i];
            current_piece.pos_y += kick_table[i+1];
            can_rotate = 1;
        }
    }

    if (!can_rotate) {
        current_piece.rotation -= dir;
        if (current_piece.rotation < 0) {
            current_piece.rotation = 3;
        } else {
            current_piece.rotation = current_piece.rotation % 4;
        }
    }

    return can_rotate;
}

int move_piece(int dir)
{
    if (is_overlap(dir, 0)) {
        return 0;
    }
    current_piece.pos_x += dir;
    return 1;
}

void move_piece_to_matrix(void)
{
    for (int i = 0; i < tetrominos[current_piece.type].size; i++) {
        for (int j = 0; j < tetrominos[current_piece.type].size; j++) {
            if (tetrominos[current_piece.type].directions[current_piece.rotation][j][i] == 1) {
                matrix[current_piece.pos_x + i - 1][current_piece.pos_y + j - 1] = tetrominos[current_piece.type].color;
            }
        }
    }
}

void hold_piece(void)
{
    if (!held) {
        if (hold == 7) {
            hold = current_piece.type;
            current_piece.type = piece_queue[current_piece_index];
            current_piece_index++;
            current_piece_index = current_piece_index % 14;
        } else {
            int temp = current_piece.type;
            current_piece.type = hold;
            hold = temp;
        }
        phase_time = 0.0;
        game_phase = FALL;
        current_piece.rotation = NORTH;
        current_piece.pos_x = 4;
        current_piece.pos_y = 20;
        if (is_overlap(0,0)) {
            CloseWindow();
        }
        held = 1;
    }
}

int handle_input(void) {
    static int moved_l = 0;
    static int moved_r = 0;
    static int moved_cw = 0;
    static int moved_ccw = 0;
    static int hard_dropped = 0;

    if (IsKeyDown(KEY_A)) {
        if (!moved_l) {
            moved_l = move_piece(-1);
            return MOVED;
        }
    } else {
        moved_l = 0;
    }

    if (IsKeyDown(KEY_D)) {
        if (!moved_r) {
            moved_r = move_piece(+1);
            return MOVED;
        }
    } else {
        moved_r = 0;
    }

    if (IsKeyDown(KEY_L)) {
        if (!moved_cw) {
            moved_cw = rotate_piece(+1);
            return MOVED;
        }
    } else {
        moved_cw = 0;
    }

    if (IsKeyDown(KEY_J)) {
        if (!moved_ccw) {
            moved_ccw = rotate_piece(-1);
            return MOVED;
        }
    } else {
        moved_ccw = 0;
    }

    if (IsKeyDown(KEY_W)) {
        if (!hard_dropped) {
            hard_dropped = 1;
            while (!is_overlap(0, -1)) {
                current_piece.pos_y--;
            }
            return HARD_DROPPED;
        }
    } else {
        hard_dropped = 0;
    }

    if (IsKeyDown(KEY_S)) {
        fall_tick = FALL_TICK / SOFT_DROP_MULT;
    } else {
        fall_tick = FALL_TICK;
    }

    if (IsKeyDown(KEY_SPACE)) {
        hold_piece();
    }

    return NONE;
}

void lock_phase(void) {
    enum InputResult action = handle_input();
    if (action == MOVED) {
        phase_time = 0.0;
    }
    if (!is_overlap(0, -1)) {
        phase_time = 0.0;
        game_phase = FALL;
    } else if (phase_time >= LOCK_TICK || action == HARD_DROPPED) {
        move_piece_to_matrix();
        phase_time = 0.0;
        game_phase = PATTERN;
    }
}

void fall_phase(void)
{
    enum InputResult action = handle_input();
    if (action == HARD_DROPPED) {
        phase_time = 0.0;
        game_phase = PATTERN;
    } else {
        if (is_overlap(0, -1)) {
            phase_time = 0.0;
            game_phase = LOCK;
        } else if (phase_time >= fall_tick || action == HARD_DROPPED) {
            phase_time = 0.0;
            current_piece.pos_y--;
        }
    }
}

void clear_line(int line)
{
    for (int y = line; y < MATRIX_HEIGHT - 1; y++) {
        for (int x = 0; x < MATRIX_WIDTH; x++) {
            matrix[x][y] = matrix[x][y+1];
            if (ColorIsEqual(matrix[x][y], WHITE) && y < 20) {
                matrix[x][y] = BLACK;
            }
        }
    }
}

void pattern_phase(void)
{
    move_piece_to_matrix();
    for (int y = 0; y < MATRIX_HEIGHT; y++) {
        int line_full = 1;
        for (int x = 0; x < MATRIX_WIDTH; x++) {
            if (ColorIsEqual(matrix[x][y], BLACK) || ColorIsEqual(matrix[x][y], WHITE)) {
                line_full = 0;
            }
        }
        if (line_full) {
            clear_line(y--);
        }
    }
    phase_time = 0.0;
    game_phase = GENERATION;
}

void game_logic(void)
{
    phase_time += GetFrameTime();
    switch (game_phase) {
        case GENERATION:
            generation_phase();
            break;
        case FALL:
            fall_phase();
            break;
        case LOCK:
            lock_phase();
            break;
        case PATTERN:
            pattern_phase();
            break;
    }
}

int main(void)
{
    srand(time(NULL));
    InitWindow(SCREEN_WIDTH, SCREEN_HEIGHT, "~turnipGod's Tetris");


    // set default block colors
    for (int y = 0; y < 40; y++) {
        for (int x = 0; x < 10; x++) {
            if (y < 20) {
                matrix[x][y] = BLACK;
            } else {
                matrix[x][y] = WHITE;
            }
        }
    }

    shuffle_bag(piece_queue);
    shuffle_bag(&(piece_queue[7]));
    phase_time = 0.0;
    game_phase = GENERATION;
    while (!WindowShouldClose()) {
        game_logic();
        BeginDrawing();
        ClearBackground(WHITE);
        render_matrix();
        EndDrawing();
    }

    CloseWindow();

    return 0;
}