<?php declare(strict_types = 1);

namespace CMS\Data;
include_once(__DIR__ . '/../helpers/array.php');

/**
*    Database class that handles all database
*    connections and related actions.
*
*   @param $user        The connecting user
*   @param $pass        Password for the $user
*   @param $database    The database to connect to
*   @param $server      The server the database is on
*   @param $port        [Optional] Port number of the $server
*/
class Database
{
    public $connection;
    private $userName;
    private $password;
    private $databaseName;
    private $server;
    private $port;
    private $isConnected;
    private $connectionAttempts;

    public function __construct($user, $pass, $database, $server, $port = "")
    {
        $this->userName = $user;
        $this->password = $pass;
        $this->databaseName = $database;
        $this->server = $server;
        $this->port = $port;
        $this->isConnected = false;
        $this->connectionAttempts = 0;
    }

    /*
        Connects to the database via MySQLi and sets the
        local $isConnected variable.
    */
    public function connect()
    {
        if (!$this->isConnected)
        {
            $this->connection = new \mysqli($this->server, $this->userName, $this->password, $this->databaseName);

            if ($this->connection->connect_errno)
            {
                echo "Sorry, something went wrong with your connection.\n";
                echo "Error: Failed to make a MySQL connection to the database: <strong>" . $this->databaseName . "</strong>\n";
                echo "Errno: " . $this->connection->connect_errno . "\n";
                echo "Error: " . $this->connection->connect_error;
                exit;
            }

            $this->isConnected = true;
        }
    }

    /**
    *   Runs a select query and returns the associative array or false.
    *
    *   @param $table       A string of the table name
    *   @param $columns     An array of column names or a string value ('*', 'name', etc.)
    *   @param $options     An associative array of options (where, order by, like, etc.)
    *                       Ex: ['where' => 'this', '=' => 'that'],
    *                           ['where' => 'this', 'like' => 'that'],
    *                           ['order by' => 'this']
    *   @param $andOrArray      [Optional] An array with a collection of 'and' or 'or' used after each pair of $options
    */
    public function select($table, $columns, $options, $andOrArray = [])
    {
        if ($this->isConnected)
        {
            $index = 0;
            $query = "SELECT ";
            $query .= $this->buildSelectColumns($query, $table, $columns, $numColumns, $index);

            foreach ($options as $key => $value)
            {
                $query = $this->buildSelectOptions($query, $key, $value);
            }

            echo $query. "<br />";

            if ($result = $this->query($query))
            {
                $sqlResults = $result->fetch_assoc();
                $result->free();
                return $sqlResults;
            }
            else
            {
                return false;
            }

            $this->connection->close();
        }
        else
        {
            $this->connect();
        }
    }

    /**
    *   Runs an insert query and returns the insert id
    *
    *   @param $table       A string of the table name
    *   @param $columns     An array of the columns names
    *   @param $values      An array of the inserted values
    */
    public function insert($table, $columns, $values)
    {
        if ($this->isConnected)
        {
            $numColumns = \count($columns);
            $numValues = \count($values);
            $index = 0;

            $query = "INSERT INTO `" . $table . "` ";
            $query .= "(";

            foreach ($columns as $c)
            {
                $query .= $c;

                if (++$index !== $numColumns)
                {
                    $query .= ", ";
                }
            }

            $index = 0;
            $query .= ") VALUES (";

            foreach ($values as $v)
            {
                if (\is_string($v))
                {
                    $query .= "'" . $v . "'";
                }
                else
                {
                    $query .= $v;
                }

                if (++$index !== $numValues)
                {
                    $query .= ", ";
                }
            }

            $query .= ")";

            $this->query($query);
            return $this->connection->insert_id;
        }
        else
        {
            $this->connect();
        }
    }

    /*
        Returns if there is a connection to the database
    */
    public function getConnection()
    {
        return $this->isConnected;
    }

    /**
    *   Runs a SQL query and returns the result.
    *   Only attempts to connect 3 times before failing.
    *
    *   @param $sql  The SQL statement to run a query on
    */
    private function query($sql)
    {
        if ($this->isConnected)
        {
            return $this->connection->query($sql);
        }
        else
        {
            if ($this->connectionAttempts < 3)
            {
                $this->connect();
                $this->query($sql);
                $this->connectionAttempts++;
            }
            else
            {
                die("Cannot connect to database: <strong>" . $this->databaseName . "</strong>. Please check your connection information.");
            }
        }
    }

    /*
        Helper function to build the columns query for
        the select function.
    */
    private function buildSelectColumns(&$query, $table, $columns, $index)
    {
        $numColumns = \count($columns);
        $isString = \is_string($columns);

        if ($isString && $columns == "*")
        {
            $query .= "* FROM `" . $table . "` ";

        }
        elseif ($isString)
        {
            $query .= $columns;

            if (++$index !== $numColumns)
            {
                $query .= ", ";
            }
            else
            {
                " FROM `" . $table . "` ";
            }
        }
        else
        {
            foreach ($columns as $c)
            {
                if (\is_string($c))
                {
                    $query .= "'" . $c . "'";
                }
                else
                {
                    $query .= $c;
                }

                if (++$index !== $numColumns)
                {
                    $query .= ", ";
                }
            }
        }
    }

    /*
        Helper function to build the options query for
        the select function.
    */
    private function buildSelectOptions(&$query, $key, $value)
    {
        $index = 0;
        $valCount = \count($value);
        $query .= \strtoupper($key) . " ";

        foreach ($value as $v)
        {
            if (++$index !== $valCount)
            {
                $query .= $v . " ";
            }
            else
            {
                if (\strcasecmp($v, "like") == 0)
                {
                    $query .= "'%" . $v . "%'";
                }
                else
                {
                    $query .= "'" . $v . "'";
                }
            }
        }

        return $query;
    }
}