<?php

class Database {
  private $handle = null;

  public static $db;

  public function __construct() {
    $this->handle = new mysqli(Config::$dbHost, Config::$dbUser, Config::$dbPass, Config::$dbName);
    $this->handle->set_charset("utf8");

    if($this->handle->connect_error) {
      ErrorHandler::$eh->addError("Database Error: Connection failed (" . $this->handle->connect_error . ")");
    }
  }

  public function executeQuery($query) {
    return $this->handle->query($query);
  }

  public function getString($what, $from, $where, $like) {
    if(gettype($where) == "array" && gettype($like) == "array") {
      $whereString = "";
      foreach($where as $key => $value) {
        if($key > 0) {
          $whereString .= " AND";
        }
        $whereString .= " `" . $value . "` LIKE '" . $like[$key] . "'";
      }
      $query = "SELECT `" . $what . "` FROM `" . $from . "` WHERE " . $whereString . ";";
    } else {
      $query = "SELECT `" . $what . "` FROM `" . $from . "` WHERE `" . $where . "` LIKE '" . $like . "';";
    }

    $res = $this->handle->query($query);
    if($res === false) {
      ErrorHandler::$eh->addError("Database Error: " . $this->handle->error);
      return false;
    } else if($res->num_rows != 1) {
      ErrorHandler::$eh->addError("Database Error: Found more than one or less than one result in getString (" . $what . ")");
      return false;
    }

    return $res->fetch_row()[0];
  }

  public function getAllAssoc($from, $where = null, $like = null) {
    if(gettype($where) == "array" && gettype($like) == "array") {
      $whereString = "";
      foreach($where as $key => $value) {
        if($key > 0) {
          $whereString .= " AND";
        }
        $whereString .= " `" . $value . "` LIKE '" . $like[$key] . "'";
      }
      $query = "SELECT * FROM `" . $from . "` WHERE " . $whereString . ";";
    } else if($where && $like) {
      $query = "SELECT * FROM `" . $from . "` WHERE `" . $where . "` LIKE '" . $like . "';";
    } else {
      $query = "SELECT * FROM `" . $from . "`;";
    }

    $res = $this->handle->query($query);
    if($res === false) {
      echo "DB failed.";
      error_log("Failed query: " . $query . PHP_EOL);
      trigger_error('Database failed: '  . $this->handle->connect_error, E_USER_ERROR);
      exit(1);
    } else if($res->num_rows < 1) {
      ErrorHandler::$eh->addError("Database error: no result (getAllAssoc)");
      //exit(1);
    }

    return $res->fetch_all(MYSQLI_ASSOC);
  }

  public function getAllAssocCustom($from, $custom, $where = null, $like = null) {
    if(gettype($where) == "array" && gettype($like) == "array") {
      $whereString = "";
      foreach($where as $key => $value) {
        if($key > 0) {
          $whereString .= " AND";
        }
        $whereString .= " `" . $value . "` LIKE '" . $like[$key] . "'";
      }
      $query = "SELECT * FROM `" . $from . "` WHERE " . $whereString . " " . $custom . ";";
    } else if($where && $like) {
      $query = "SELECT * FROM `" . $from . "` WHERE `" . $where . "` LIKE '" . $like . "' " . $custom . ";";
    } else {
      $query = "SELECT * FROM `" . $from . "` " . $custom . ";";
    }

    $res = $this->handle->query($query);
    if($res === false) {
      echo "DB failed.";
      trigger_error('Database failed: '  . $this->handle->connect_error, E_USER_ERROR);
      exit(1);
    } else if($res->num_rows < 1) {
      error_log("This shouldn't happen..3");
      //exit(1);
    }

    return $res->fetch_all(MYSQLI_ASSOC);
  }

  public function getAllRow($from, $where = null, $like = null) {
    if(gettype($where) == "array" && gettype($like) == "array") {
      $whereString = "";
      foreach($where as $key => $value) {
        if($key > 0) {
          $whereString .= " AND";
        }
        $whereString .= " `" . $value . "` LIKE '" . $like[$key] . "'";
      }
      $query = "SELECT * FROM `" . $from . "` WHERE " . $whereString . ";";
    } else if($where && $like) {
      $query = "SELECT * FROM `" . $from . "` WHERE `" . $where . "` LIKE '" . $like . "';";
    } else {
      $query = "SELECT * FROM `" . $from . "`;";
    }

    $res = $this->handle->query($query);
    if($res === false) {
      echo "DB failed.";
      trigger_error('Database failed: '  . $this->handle->connect_error, E_USER_ERROR);
      exit(1);
    } else if($res->num_rows < 1) {
      error_log("This shouldn't happen..4");
      exit(1);
    }

    return $res->fetch_all(MYSQLI_NUM);
  }

  public function getAllRowCustom($from, $custom) {
    if(gettype($where) == "array" && gettype($like) == "array") {
      $whereString = "";
      foreach($where as $key => $value) {
        if($key > 0) {
          $whereString .= " AND";
        }
        $whereString .= " `" . $value . "` LIKE '" . $like[$key] . "'";
      }
      $query = "SELECT * FROM `" . $from . "` WHERE " . $whereString . " " . $custom . ";";
    } else if($where && $like) {
      $query = "SELECT * FROM `" . $from . "` WHERE `" . $where . "` LIKE '" . $like . "' " . $custom . ";";
    } else {
      $query = "SELECT * FROM `" . $from . "` " . $custom . ";";
    }

    $res = $this->handle->query($query);
    if($res === false) {
      echo "DB failed.";
      trigger_error('Database failed: '  . $this->handle->connect_error, E_USER_ERROR);
      exit(1);
    } else if($res->num_rows < 1) {
      error_log("This shouldn't happen..5");
      //exit(1);
    }

    return $res->fetch_all(MYSQLI_NUM);
  }

  public function countRows($from, $where = null, $like = null) {
    if(gettype($where) == "array" && gettype($like) == "array") {
      $whereString = "";
      foreach($where as $key => $value) {
        if($key > 0) {
          $whereString .= " AND";
        }
        $whereString .= " `" . $value . "` LIKE '" . $like[$key] . "'";
      }
      $query = "SELECT * FROM `" . $from . "` WHERE " . $whereString . ";";
    } else if($where && $like) {
      $query = "SELECT * FROM `" . $from . "` WHERE `" . $where . "` LIKE '" . $like . "';";
    } else {
      $query = "SELECT * FROM `" . $from . "`;";
    }

    $res = $this->handle->query($query);
    if($res === false) {
      echo "DB failed.";
      trigger_error('Database failed: '  . $this->handle->connect_error, E_USER_ERROR);
      exit(1);
    } else {
      return $res->num_rows;
    }
  }

  public function insertRow($into, $cols, $vals) {
    foreach($vals as $key => $val) {
      $vals[$key] = $this->handle->real_escape_string($val);
    }
    $colString = "(`" . implode('`, `', $cols) . "`)";
    $valString = "('" . implode("', '", $vals) . "')";

    $query = "INSERT INTO `" . $into . "` " . $colString . " VALUES " . $valString . ";";

    $res = $this->handle->query($query);
    if($res === false) {
      echo "DB failed.";
      trigger_error('Database failed: '  . $this->handle->error, E_USER_ERROR);
      exit(1);
    } else {
      return $this->handle->insert_id;
    }
  }

  public function deleteRows($from, $where, $like) {
    if(gettype($where) == "array" && gettype($like) == "array") {
      $whereString = "";
      foreach($where as $key => $value) {
        if($key > 0) {
          $whereString .= " AND";
        }
        $whereString .= " `" . $value . "` LIKE '" . $like[$key] . "'";
      }
      $query = "DELETE FROM `" . $from . "` WHERE " . $whereString . ";";
    } else if($where && $like) {
      $query = "DELETE FROM `" . $from . "` WHERE `" . $where . "` LIKE '" . $like . "';";
    }

    $res = $this->handle->query($query);
    if($res === false) {
      echo "DB failed.";
      trigger_error('Database failed: '  . $this->handle->connect_error, E_USER_ERROR);
      exit(1);
    } else {
      return true;
    }
  }

  public function updateRow($update, $col, $val, $where, $like) {
    if(gettype($col) == "array" && gettype($val) == "array") {
      $setString = "SET";
      foreach($col as $key => $value) {
        if($key > 0) {
          $setString .= " ,";
        }
        $setString .= " `" . $value . "` = '" . $val[$key] . "'";
      }
    } else {
      $setString = " `" . $col . "` = '" . $val . "'";
    }

    if(gettype($where) == "array" && gettype($like) == "array") {
      $whereString = "";
      foreach($where as $key => $value) {
        if($key > 0) {
          $whereString .= " AND";
        }
        $whereString .= " `" . $value . "` LIKE '" . $like[$key] . "'";
      }
    } else if($where && $like) {
      $whereString = "`" . $where . "` LIKE '" . $like . "'";
    }

    $query = "UPDATE `" . $update . "` " . $setString . " WHERE " . $whereString . ";";

    $res = $this->handle->query($query);
    if($res === false) {
      echo "DB failed.";
      trigger_error('Database failed: '  . $this->handle->connect_error, E_USER_ERROR);
      exit(1);
    } else {
      return true;
    }
  }
}