#include "Twos.h"
#include <lvgl/lvgl.h>
#include <string>
#include <charconv>
#include <array>
#include <vector>
#include <utility>

using namespace Pinetime::Applications::Screens;

Twos::Twos(Pinetime::Applications::DisplayApp* app) : Screen(app) {

  // create styles to apply to different valued tiles
  lv_style_init(&style_cell1);
  lv_style_init(&style_cell2);
  lv_style_init(&style_cell3);
  lv_style_init(&style_cell4);
  lv_style_init(&style_cell5);

  lv_style_set_border_color(&style_cell1, LV_STATE_DEFAULT, lv_color_hex(0xbbada0));
  lv_style_set_border_width(&style_cell1, LV_STATE_DEFAULT, 3);
  lv_style_set_bg_opa(&style_cell1, LV_STATE_DEFAULT, LV_OPA_COVER);
  lv_style_set_bg_color(&style_cell1, LV_STATE_DEFAULT, lv_color_hex(0xcdc0b4));
  lv_style_set_pad_top(&style_cell1, LV_STATE_DEFAULT, 25);
  lv_style_set_text_color(&style_cell1, LV_STATE_DEFAULT, LV_COLOR_BLACK);

  lv_style_set_border_color(&style_cell2, LV_STATE_DEFAULT, lv_color_hex(0xbbada0));
  lv_style_set_border_width(&style_cell2, LV_STATE_DEFAULT, 3);
  lv_style_set_bg_opa(&style_cell2, LV_STATE_DEFAULT, LV_OPA_COVER);
  lv_style_set_bg_color(&style_cell2, LV_STATE_DEFAULT, lv_color_hex(0xefdfc6));
  lv_style_set_pad_top(&style_cell2, LV_STATE_DEFAULT, 25);
  lv_style_set_text_color(&style_cell2, LV_STATE_DEFAULT, LV_COLOR_BLACK);

  lv_style_set_border_color(&style_cell3, LV_STATE_DEFAULT, lv_color_hex(0xbbada0));
  lv_style_set_border_width(&style_cell3, LV_STATE_DEFAULT, 3);
  lv_style_set_bg_opa(&style_cell3, LV_STATE_DEFAULT, LV_OPA_COVER);
  lv_style_set_bg_color(&style_cell3, LV_STATE_DEFAULT, lv_color_hex(0xef9263));
  lv_style_set_pad_top(&style_cell3, LV_STATE_DEFAULT, 25);

  lv_style_set_border_color(&style_cell4, LV_STATE_DEFAULT, lv_color_hex(0xbbada0));
  lv_style_set_border_width(&style_cell4, LV_STATE_DEFAULT, 3);
  lv_style_set_bg_opa(&style_cell4, LV_STATE_DEFAULT, LV_OPA_COVER);
  lv_style_set_bg_color(&style_cell4, LV_STATE_DEFAULT, lv_color_hex(0xf76142));
  lv_style_set_pad_top(&style_cell4, LV_STATE_DEFAULT, 25);

  lv_style_set_border_color(&style_cell5, LV_STATE_DEFAULT, lv_color_hex(0xbbada0));
  lv_style_set_border_width(&style_cell5, LV_STATE_DEFAULT, 3);
  lv_style_set_bg_opa(&style_cell5, LV_STATE_DEFAULT, LV_OPA_COVER);
  lv_style_set_bg_color(&style_cell5, LV_STATE_DEFAULT, lv_color_hex(0x007dc5));
  lv_style_set_pad_top(&style_cell5, LV_STATE_DEFAULT, 25);

  // format grid display

  gridDisplay = lv_table_create(lv_scr_act(), nullptr);
  lv_obj_add_style(gridDisplay, LV_TABLE_PART_CELL1, &style_cell1);
  lv_obj_add_style(gridDisplay, LV_TABLE_PART_CELL2, &style_cell2);
  lv_obj_add_style(gridDisplay, LV_TABLE_PART_CELL3, &style_cell3);
  lv_obj_add_style(gridDisplay, LV_TABLE_PART_CELL4, &style_cell4);
  lv_obj_add_style(gridDisplay, LV_TABLE_PART_CELL4 + 1, &style_cell5);
  lv_table_set_col_cnt(gridDisplay, 4);
  lv_table_set_row_cnt(gridDisplay, 4);
  lv_table_set_col_width(gridDisplay, 0, LV_HOR_RES / 4);
  lv_table_set_col_width(gridDisplay, 1, LV_HOR_RES / 4);
  lv_table_set_col_width(gridDisplay, 2, LV_HOR_RES / 4);
  lv_table_set_col_width(gridDisplay, 3, LV_HOR_RES / 4);
  lv_obj_align(gridDisplay, NULL, LV_ALIGN_IN_BOTTOM_MID, 0, 0);

  lv_obj_clean_style_list(gridDisplay, LV_TABLE_PART_BG);

  // initialize grid
  for (int row = 0; row < 4; row++) {
    for (int col = 0; col < 4; col++) {
      grid[row][col].value = 0;
      lv_table_set_cell_type(gridDisplay, row, col, 1);
      lv_table_set_cell_align(gridDisplay, row, col, LV_LABEL_ALIGN_CENTER);
    }
  }
  placeNewTile();
  placeNewTile();

  // format score text
  scoreText = lv_label_create(lv_scr_act(), nullptr);
  lv_obj_set_width(scoreText, LV_HOR_RES);
  lv_label_set_align(scoreText, LV_ALIGN_IN_LEFT_MID);
  lv_obj_align(scoreText, nullptr, LV_ALIGN_IN_TOP_LEFT, 0, 10);
  lv_label_set_recolor(scoreText, true);
  lv_label_set_text_fmt(scoreText, "Score #FFFF00 %i#", score);

  lv_obj_t* backgroundLabel = lv_label_create(lv_scr_act(), nullptr);
  lv_label_set_long_mode(backgroundLabel, LV_LABEL_LONG_CROP);
  lv_obj_set_size(backgroundLabel, 240, 240);
  lv_obj_set_pos(backgroundLabel, 0, 0);
  lv_label_set_text(backgroundLabel, "");
}

Twos::~Twos() {
  lv_style_reset(&style_cell1);
  lv_style_reset(&style_cell2);
  lv_style_reset(&style_cell3);
  lv_style_reset(&style_cell4);
  lv_style_reset(&style_cell5);
  lv_obj_clean(lv_scr_act());
}

bool Twos::placeNewTile() {
  std::vector<std::pair<int, int>> availableCells;
  for (int row = 0; row < 4; row++) {
    for (int col = 0; col < 4; col++) {
      if (!grid[row][col].value) {
        availableCells.push_back(std::make_pair(row, col));
      }
    }
  }

  if (availableCells.size() == 0) {
    return false; // game lost
  }

  auto it = availableCells.cbegin();
  int random = rand() % availableCells.size();
  std::advance(it, random);
  std::pair<int, int> newCell = *it;

  if ((rand() % 100) < 90)
    grid[newCell.first][newCell.second].value = 2;
  else
    grid[newCell.first][newCell.second].value = 4;
  updateGridDisplay(grid);
  return true;
}

bool Twos::tryMerge(Tile grid[][4], int& newRow, int& newCol, int oldRow, int oldCol) {
  if ((grid[newRow][newCol].value == grid[oldRow][oldCol].value)) {
    if ((newCol != oldCol) || (newRow != oldRow)) {
      if (!grid[newRow][newCol].merged) {
        unsigned int newVal = grid[oldRow][oldCol].value *= 2;
        grid[newRow][newCol].value = newVal;
        score += newVal;
        lv_label_set_text_fmt(scoreText, "Score #FFFF00 %i#", score);
        grid[oldRow][oldCol].value = 0;
        grid[newRow][newCol].merged = true;
        return true;
      }
    }
  }
  return false;
}

bool Twos::tryMove(Tile grid[][4], int newRow, int newCol, int oldRow, int oldCol) {
  if (((newCol >= 0) && (newCol != oldCol)) || ((newRow >= 0) && (newRow != oldRow))) {
    grid[newRow][newCol].value = grid[oldRow][oldCol].value;
    grid[oldRow][oldCol].value = 0;
    return true;
  }
  return false;
}

bool Twos::OnTouchEvent(Pinetime::Applications::TouchEvents event) {
  bool validMove = false;
  for (int row = 0; row < 4; row++) {
    for (int col = 0; col < 4; col++) {
      grid[row][col].merged = false; // reinitialize merge state
    }
  }
  switch (event) {
    case TouchEvents::SwipeLeft:
      for (int col = 1; col < 4; col++) { // ignore tiles already on far left
        for (int row = 0; row < 4; row++) {
          if (grid[row][col].value) {
            int newCol = -1;
            for (int potentialNewCol = col - 1; potentialNewCol >= 0; potentialNewCol--) {
              if (!grid[row][potentialNewCol].value) {
                newCol = potentialNewCol;
              } else { // blocked by another tile
                if (tryMerge(grid, row, potentialNewCol, row, col))
                  validMove = true;
                break;
              }
            }
            if (tryMove(grid, row, newCol, row, col))
              validMove = true;
          }
        }
      }
      if (validMove) {
        placeNewTile();
      }
      return true;
    case TouchEvents::SwipeRight:
      for (int col = 2; col >= 0; col--) { // ignore tiles already on far right
        for (int row = 0; row < 4; row++) {
          if (grid[row][col].value) {
            int newCol = -1;
            for (int potentialNewCol = col + 1; potentialNewCol < 4; potentialNewCol++) {
              if (!grid[row][potentialNewCol].value) {
                newCol = potentialNewCol;
              } else { // blocked by another tile
                if (tryMerge(grid, row, potentialNewCol, row, col))
                  validMove = true;
                break;
              }
            }
            if (tryMove(grid, row, newCol, row, col))
              validMove = true;
          }
        }
      }
      if (validMove) {
        placeNewTile();
      }
      return true;
    case TouchEvents::SwipeUp:
      for (int row = 1; row < 4; row++) { // ignore tiles already on top
        for (int col = 0; col < 4; col++) {
          if (grid[row][col].value) {
            int newRow = -1;
            for (int potentialNewRow = row - 1; potentialNewRow >= 0; potentialNewRow--) {
              if (!grid[potentialNewRow][col].value) {
                newRow = potentialNewRow;
              } else { // blocked by another tile
                if (tryMerge(grid, potentialNewRow, col, row, col))
                  validMove = true;
                break;
              }
            }
            if (tryMove(grid, newRow, col, row, col))
              validMove = true;
          }
        }
      }
      if (validMove) {
        placeNewTile();
      }
      return true;
    case TouchEvents::SwipeDown:
      for (int row = 2; row >= 0; row--) { // ignore tiles already on bottom
        for (int col = 0; col < 4; col++) {
          if (grid[row][col].value) {
            int newRow = -1;
            for (int potentialNewRow = row + 1; potentialNewRow < 4; potentialNewRow++) {
              if (!grid[potentialNewRow][col].value) {
                newRow = potentialNewRow;
              } else { // blocked by another tile
                if (tryMerge(grid, potentialNewRow, col, row, col))
                  validMove = true;
                break;
              }
            }
            if (tryMove(grid, newRow, col, row, col))
              validMove = true;
          }
        }
      }
      if (validMove) {
        placeNewTile();
      }
      return true;
    default:
      return false;
  }
  return false;
}

void Twos::updateGridDisplay(Tile grid[][4]) {
  for (int row = 0; row < 4; row++) {
    for (int col = 0; col < 4; col++) {
      if (grid[row][col].value) {
        lv_table_set_cell_value(gridDisplay, row, col, (std::to_string(grid[row][col].value)).c_str());
      } else {
        lv_table_set_cell_value(gridDisplay, row, col, "");
      }
      switch (grid[row][col].value) {
        case 0:
          lv_table_set_cell_type(gridDisplay, row, col, 1);
          break;
        case 2:
        case 4:
          lv_table_set_cell_type(gridDisplay, row, col, 2);
          break;
        case 8:
        case 16:
          lv_table_set_cell_type(gridDisplay, row, col, 3);
          break;
        case 32:
        case 64:
          lv_table_set_cell_type(gridDisplay, row, col, 4);
          break;
        default:
          lv_table_set_cell_type(gridDisplay, row, col, 5);
          break;
      }
    }
  }
}