<?php
  require_once('../config.php');

  /* val
   * 
   * select => ['var1', 'var2'...]
   * insert|update|where => ['key1' => 'value1', 'key2' => 'value2'...]
   * order => ['var', 'asc'|'desc']
   * limit => int
   * */
  function lolidb (string $table, array $val, string $mode='select'): array|bool {
    // モードは違う場合、やめる。If the mode is wrong, stop.
    if ($mode != 'select' && $mode != 'one' && $mode != 'insert' && $mode != 'update' && $mode != 'delete') {
      dd("モードは「select」、「one」、「insert」、「update」、「delete」です。\nMode should be \"select\", \"one\", \"insert\", \"update\", or \"delete\".");
      return false;
    }

    // 順のチェック。Check order.
    if (isset($val['order'])) {
      // selectかoneじゃない場合。If not select or one.
      if ($mode !== 'select' || $mode !== 'one') {
        dd("「order」は「select」又は「one」のみで使えます。\n\"order\" can only be used with \"select\" or \"one\".");
        return false;
      }

      // 複数の場合。If multiple.
      if (count($val['order'] > 1)) {
        dd("複数「order」は未対応です。\nMultiple \"order\" is not yet supported.");
        return false;
      }

      // ascかdescかどうか。Whether it's asc or desc.
      foreach ($val['order'] as $k => $v) {
        if ($v !== 'asc' && $v !== 'desc') {
          dd("「order」は「asc」又は「desc」です。\n\"order\" should be \"asc\" or \"desc\".");
          return false;
        }
      }
    }

    // 限界のチェック。Check limit.
    if (($mode === 'select' || $mode === 'one') && isset($val['limit'])) {
      // oneの場合。If one.
      if ($mode === 'one') {
        dd("「one」の場合、「limit」はいつでも「1」です。「limit」は1以上は必要の場合、「select」を使って下さい。\nIn case of \"one\", \"limit\" is always \"1\". If \"limit\" needs to be more than \"1\", please use \"select\".");
        return false;
      }

      // selectじゃない場合。If not select.
      else if ($mode !== 'select') {
        dd("「insert」、「update」及び「delete」で、「limit」を使えません。\n\"limit\" cannot be used with \"insert\", \"update\", and \"delete\".");
        return false;
      }
    }

    // insertの場合。In case of insert.
    if ($mode === 'insert' && !isset($val['insert'])) {
      dd("「insert」モードの場合、「insert」値は必須です。\nIn case of \"insert\" mode, \"insert\" value is necessary.");
      return false;
    }

    // updateの場合。In case of update.
    if ($mode === 'update' && !isset($val['update'])) {
      dd("「update」モードの場合、「update」値は必須です。\nIn case of \"update\" mode, \"update\" value is necessary.");
      return false;
    }

    // MySQLiの創作。Creation of MySQLi.
    $mysqli = mysqli_connect(DB_HOST, DB_USER, DB_PASS, DB_TABLE);
    $result = null;

    if ($mode == 'select' || $mode == 'one') {
      // select値がなければ、全部を選択する。If there is no select value, select everything.
      if (!isset($val['select'])) {
        $val['select'] = ['*'];
      }

      $query = 'SELECT '.$val['select'].' FROM '.$table;

      if (isset($val['where'])) {
        $query .= ' WHERE ';
        foreach ($val['where'] as $k => $v) {
          $query .= $k.' = '.$v;
          if ($k !== array_key_last($val['where'])) $query .= ' AND ';
        }
      }

      if (isset($val['order'])) {
        $query .= ' ORDER BY ';
        foreach ($val['order'] as $k => $v) {
          $query .= $k;
          $query .= ' '.strtoupper($v);
        }
      }

      if ($mode == 'one') {
        $query .= ' LIMIT 1';
      }
      else {
        if (isset($val['limit'])) {
          $query .= ' LIMIT '.(int)$val['limit'];
        }
      }

      $result = mysqli_query($mysqli, $query.';');
      $row = mysqli_fetch_assoc($result);
    }
    else {
      if ($mode == 'insert') {
        $query .= 'INSERT INTO '.$table.' (';
        foreach ($val['insert'] as $k => $v) {
          $query .= $k;
          if ($k !== array_key_last($val['insert'])) {
            $query .= ', ';
          }
        }
        $query .= ') VALUES (';
        foreach ($val['insert'] as $k => $v) {
          $query .= $v;
          if ($k !== array_key_last($val['insert'])) {
            $query .= ', ';
          }
        }
        $query .= ')';
      }
      else if ($mode == 'update') {
        $query .= 'UPDATE '.$table.' SET ';
        foreach ($val['update'] as $k => $v) {
          $query .= $k.' = '.$v;
          if ($k !== array_key_last($val['update'])) {
            $query .= ', ';
          }
        }

        if (isset($val['where'])) {
          $query .= ' WHERE ';
          foreach ($val['where'] as $k => $v) {
            $query .= $k.' = '.$v;
            if ($k !== array_key_last($val['where'])) {
              $query .= ' AND ';
            }
          }
        }
      }
      else if ($mode == 'delete') {
        $query .= 'DELETE FROM '.$table;

        if (isset($val['where'])) {
          $query .= ' WHERE ';
          foreach ($val['where'] as $k => $v) {
            $query .= $k.' = '.$v;
            if ($k !== array_key_last($val['where'])) {
              $query .= ' AND ';
            }
          }
        }
      }

      $stmt = mysqli_prepare($mysqli, $query.';');
    }

    return $row;
  }
?>