#include "ui.h"
#include "game.h"
#include <math.h>
#include <raylib.h>
#include <stdbool.h>
#include <stdio.h>

const Color tile_colors[] = {
    LIGHTGRAY, // 0 - Empty
    BEIGE,     // 2
    GOLD,      // 4
    ORANGE,    // 8
    ORANGE,    // 16
    RED,       // 32
    MAROON,    // 64
    YELLOW,    // 128
    GOLD,      // 256
    ORANGE,    // 512
    RED,       // 1024
    MAROON,    // 2048
    PINK,      // 4096
    MAGENTA,   // 8192
};

static bool is_dragging;
static Vector2 drag_start_pos;
static bool is_animating;

// Common logic shared between both input handlers
static void after_input(GameState_t *game_state) {
  if (!spawn_tile(game_state) && !can_move(game_state)) {
    game_state->status = LOST;
    return;
  }

  // We moved, merged or spawned a tile, so we will be animating
  is_animating = true;

  // TODO: Allow for infinite play
  for (int y = 0; y < BOARD_HEIGHT; y++) {
    for (int x = 0; x < BOARD_WIDTH; x++) {
      if (game_state->board[y][x] == 2048) {
        game_state->status = WON;
        return;
      }
    }
  }

  FILE *f = fopen("save.dat", "wb");
  if (f) {
    fwrite(game_state, sizeof(GameState_t), 1, f);
    fclose(f);
  }
}

void handle_mouse_input(GameState_t *game_state) {
  // Don't allow any input while animating so we stay in sync
  if (is_animating)
    return;

  if (IsMouseButtonPressed(MOUSE_LEFT_BUTTON)) {
    drag_start_pos = GetMousePosition();

    // Check for the normal reset button
    if (game_state->status == PLAYING) {
      if (drag_start_pos.x >= 500 && drag_start_pos.x <= 775 && drag_start_pos.y >= 455 && drag_start_pos.y <= 479) {
        reset_board(game_state);
        return;
      }
    } else {
      // Check for the "Play again" button
      if (drag_start_pos.x >= 300 && drag_start_pos.x <= 500 && drag_start_pos.y >= 450 && drag_start_pos.y <= 490) {
        reset_board(game_state);
        return;
      }
    }

    if (game_state->status == PLAYING)
      is_dragging = true;
  } else if (IsMouseButtonReleased(MOUSE_LEFT_BUTTON) && is_dragging) {
    Vector2 current_pos = GetMousePosition();

    float dx = current_pos.x - drag_start_pos.x;
    float dy = current_pos.y - drag_start_pos.y;

    float drag_distance = sqrt(dx * dx + dy * dy);

    // We don't want to register single clicks as a move
    if (drag_distance >= 30) {
      if (fabs(dx) > fabs(dy)) {
        if (dx > 0) {
          move(game_state, RIGHT);
        } else {
          move(game_state, LEFT);
        }
      } else {
        if (dy > 0) {
          move(game_state, DOWN);
        } else {
          move(game_state, UP);
        }
      }
      after_input(game_state);
    }
    is_dragging = false;
  }
}

void handle_keyboard_input(GameState_t *game_state) {
  if (IsKeyReleased(KEY_R) || (game_state->status != PLAYING && IsKeyReleased(KEY_ENTER))) {
    reset_board(game_state);
  }

  if (IsKeyReleased(KEY_UP)) {
    move(game_state, UP);
  } else if (IsKeyReleased(KEY_DOWN)) {
    move(game_state, DOWN);
  } else if (IsKeyReleased(KEY_LEFT)) {
    move(game_state, LEFT);
  } else if (IsKeyReleased(KEY_RIGHT)) {
    move(game_state, RIGHT);
  } else {
    return;
  }

  after_input(game_state);
}

// Main render loop, responsible ONLY for redering
void render(GameState_t *game_state) {
  for (int y = 0; y < BOARD_HEIGHT; y++) {
    for (int x = 0; x < BOARD_WIDTH; x++) {
      int tile_value = game_state->board[y][x];
      int pos_x = BOARD_MARGIN + x * (TILE_SIZE + TILE_SPACING);
      int pos_y = BOARD_MARGIN + y * (TILE_SIZE + TILE_SPACING);
      int color_index = (tile_value == 0) ? 0 : (int)log2(tile_value);

      if ((size_t)color_index >= sizeof(tile_colors) / sizeof(tile_colors[0])) {
        color_index = sizeof(tile_colors) / sizeof(tile_colors[0]) - 1; // Cap to the last color
      }

      DrawRectangle(pos_x, pos_y, TILE_SIZE, TILE_SIZE, tile_colors[color_index]);
      if (tile_value != 0) {
        const char *text = TextFormat("%d", tile_value);
        DrawText(text, pos_x + TILE_SIZE / 2 - MeasureText(text, 20) / 2, pos_y + TILE_SIZE / 2 - 10, 20, BLACK);
      }
    }
  }

  DrawText(TextFormat("Score: %d", game_state->score), WINDOW_HEIGHT, BOARD_MARGIN, 20, BLACK);
  DrawText(TextFormat("Moves used: %d", game_state->moves_made), WINDOW_HEIGHT, BOARD_MARGIN + 20, 20, BLACK);

  if (game_state->status == PLAYING) {
    DrawText("Drag with the mouse to move tiles", 400 - MeasureText("Drag with the mouse to move tiles", 20) / 2,
             WINDOW_HEIGHT - 40, 20, GRAY);

    // Reset button
    DrawRectangle(500, 455, 275, 24, RED);
    DrawText("Reset", 500 + 275 / 2 - MeasureText("Reset", 20) / 2, 455 + 4, 20, WHITE);
  } else {
    Color overlay = Fade(BLACK, 0.7f);
    DrawRectangle(0, 0, WINDOW_WIDTH, 700, overlay);

    if (game_state->status == WON) {
      DrawText("You win!", 400 - MeasureText("You win!", 40) / 2, 250, 40, GREEN);
    } else if (game_state->status == LOST) {
      DrawText("Game over!", 400 - MeasureText("Game over!", 40) / 2, 250, 40, RED);
    }

    // Draw the scores under the win/loss message
    DrawText(TextFormat("Score: %d", game_state->score),
             400 - MeasureText(TextFormat("Score: %d", game_state->score), 20) / 2, 290, 20, WHITE);
    DrawText(TextFormat("Moves used: %d", game_state->moves_made),
             400 - MeasureText(TextFormat("Moves used: %d", game_state->moves_made), 20) / 2, 310, 20, WHITE);

    DrawRectangle(400 - 100, 450, 200, 40, RED);
    DrawText("Try again", 400 - MeasureText("Try again", 20) / 2, 455 + 4, 20, WHITE);
  }
}