<?php
namespace W3TC;

/**
 * class Config
 * Provides configuration data using cache
 */
class ConfigDbStorage {
	/**
	 * Reads config from database
	 * Stored in this class to limit class loading
	 */
	static public function util_array_from_storage( $blog_id, $preview ) {
		$content = self::load_content( $blog_id, $preview );
		$config = @json_decode( $content, true );

		if ( is_array( $config ) )
			return $config;

		return null;
	}



	static public function is_item_exists( $blog_id, $preview ) {
		$content = self::load_content( $blog_id, $preview );
		return is_null( $content );
	}



	static public function remove_item( $blog_id, $preview ) {
		$table = self::get_table( $blog_id );
		$option_name = self::get_option_name( $blog_id, $preview );

		global $wpdb;
		$wpdb->query( $wpdb->prepare(
			"DELETE FROM $table WHERE option_name = %s",
			$option_name ) );
	}



	/**
	 * Deploys the config file from a preview config file
	 *
	 * @param integer $direction     +1: preview->production
	 *                           -1: production->preview
	 * @param boolean $remove_source remove source file
	 */
	static public function preview_production_copy( $blog_id, $direction ) {
		if ( $direction > 0 ) {
			$content = self::load_content( $blog_id, true );
			self::save_item( $blog_id, false, $content );
		} else {
			$content = self::load_content( $blog_id, false );
			self::save_item( $blog_id, true, $content );
		}
	}



	static public function save_item( $blog_id, $preview, $data ) {
		if ( is_string( $data ) ) {
			$config = $data;
		} else {
			$config = json_encode( $data );
		}

		$table = self::get_table( $blog_id );
		$option_name = self::get_option_name( $blog_id, $preview );

		global $wpdb;
		$is_exists = !is_null( self::load_content( $blog_id, $preview ) );

		if ( $is_exists ) {
			$wpdb->query( $wpdb->prepare(
				"UPDATE $table SET option_value = %s WHERE option_name = %s",
				$config, $option_name ) );
		} else {
			$wpdb->query( $wpdb->prepare(
				"INSERT INTO $table (option_name, option_value) VALUES (%s, %s)",
				$option_name, $config ) );
		}
	}



	static private function get_table( $blog_id ) {
		if ( defined('W3TC_CONFIG_DATABASE_TABLE' ) ) {
			$template = W3TC_CONFIG_DATABASE_TABLE;
		} else {
			if ( is_multisite() ) {
				error_log( 'Please use W3TC_CONFIG_DATABASE_TABLE constant, funcationality without it is not stable in multisite mode' );
			}

			global $table_prefix;
			$template = $table_prefix . 'options';
		}

		if ( $blog_id <= 0 )
			$blog_id_prefix = '';
		else
			$blog_id_prefix = $blog_id . '_';

		return str_replace('{blog_id_prefix}', $blog_id_prefix, $template);
	}



	static private function get_option_name( $blog_id, $preview ) {
		return 'w3tc_config_' . $blog_id . ( $preview ? '_preview' : '' );
	}



	static private function load_content( $blog_id, $preview ) {
		$table = self::get_table( $blog_id );
		$option_name = self::get_option_name( $blog_id, $preview );

		if ( isset( $GLOBALS['wpdb'] ) ) {
			global $wpdb;
			$row = $wpdb->get_row( $wpdb->prepare(
				"SELECT option_value FROM $table WHERE option_name = %s LIMIT 1",
				$option_name ) );
		} else {
			$db = new _WpdbEssentials( DB_USER, DB_PASSWORD, DB_NAME, DB_HOST );

			if ( $db->ready ) {
				$row = $db->get_row( $db->prepare(
					"SELECT option_value FROM $table WHERE option_name = %s LIMIT 1",
					$option_name ) );
			} else {
				error_log('Failed to load w3tc config');
				$row = null;
			}

			// close connection immediately so that real pooled connection may be
			// reused by later inialized wpdb object
			$db->close();
		}

		if ( is_object( $row ) ) {
			return $row->option_value;
		}

		return null;
	}
}



class _WpdbEssentials {
	public $last_error = '';
	public $num_rows = 0;
	var $rows_affected = 0;
	var $last_query;
	var $last_result;



	public function __construct( $dbuser, $dbpassword, $dbname, $dbhost ) {
		if ( function_exists( 'mysqli_connect' ) ) {
			if ( defined( 'WP_USE_EXT_MYSQL' ) ) {
				$this->use_mysqli = ! WP_USE_EXT_MYSQL;
			} elseif ( version_compare( phpversion(), '5.5', '>=' ) || ! function_exists( 'mysql_connect' ) ) {
				$this->use_mysqli = true;
			} elseif ( false !== strpos( $GLOBALS['wp_version'], '-' ) ) {
				$this->use_mysqli = true;
			}
		}

		$this->dbuser = $dbuser;
		$this->dbpassword = $dbpassword;
		$this->dbname = $dbname;
		$this->dbhost = $dbhost;

		$this->db_connect();
	}


	public function db_connect( $allow_bail = true ) {
		$this->is_mysql = true;

		/*
		 * Deprecated in 3.9+ when using MySQLi. No equivalent
		 * $new_link parameter exists for mysqli_* functions.
		 */
		$new_link = defined( 'MYSQL_NEW_LINK' ) ? MYSQL_NEW_LINK : true;
		$client_flags = defined( 'MYSQL_CLIENT_FLAGS' ) ? MYSQL_CLIENT_FLAGS : 0;

		if ( $this->use_mysqli ) {
			$this->dbh = mysqli_init();

			// mysqli_real_connect doesn't support the host param including a port or socket
			// like mysql_connect does. This duplicates how mysql_connect detects a port and/or socket file.
			$port = null;
			$socket = null;
			$host = $this->dbhost;
			$port_or_socket = strstr( $host, ':' );
			if ( ! empty( $port_or_socket ) ) {
				$host = substr( $host, 0, strpos( $host, ':' ) );
				$port_or_socket = substr( $port_or_socket, 1 );
				if ( 0 !== strpos( $port_or_socket, '/' ) ) {
					$port = intval( $port_or_socket );
					$maybe_socket = strstr( $port_or_socket, ':' );
					if ( ! empty( $maybe_socket ) ) {
						$socket = substr( $maybe_socket, 1 );
					}
				} else {
					$socket = $port_or_socket;
				}
			}

			if ( WP_DEBUG ) {
				mysqli_real_connect( $this->dbh, $host, $this->dbuser, $this->dbpassword, null, $port, $socket, $client_flags );
			} else {
				@mysqli_real_connect( $this->dbh, $host, $this->dbuser, $this->dbpassword, null, $port, $socket, $client_flags );
			}

			if ( $this->dbh->connect_errno ) {
				$this->dbh = null;
				$this->last_error =
					'Connection failed with ' . $this->dbh->connect_errno . ' error code';
				if ( WP_DEBUG ) {
					echo $this->last_error;
				}
			}
		} else {
			if ( WP_DEBUG ) {
				$this->dbh = mysql_connect( $this->dbhost, $this->dbuser, $this->dbpassword, $new_link, $client_flags );
			} else {
				$this->dbh = @mysql_connect( $this->dbhost, $this->dbuser, $this->dbpassword, $new_link, $client_flags );
			}
		}

		if ( $this->dbh ) {
			$this->has_connected = true;
			$this->ready = true;
			$this->select( $this->dbname, $this->dbh );
		} else {
			if ( WP_DEBUG ) {
				echo 'Failed to connect to mysql server';
			}
		}
	}



	public function select( $db, $dbh = null ) {
		if ( $this->use_mysqli ) {
			$success = mysqli_select_db( $dbh, $db );
		} else {
			$success = mysql_select_db( $db, $dbh );
		}
		if ( ! $success ) {
			$this->ready = false;
			if ( WP_DEBUG ) {
				echo 'Failed to select database';
			}
		}
	}



	public function prepare( $query, $args ) {
		$args = func_get_args();
		array_shift( $args );
		// If args were passed as an array (as in vsprintf), move them up
		if ( isset( $args[0] ) && is_array($args[0]) )
			$args = $args[0];
		$query = str_replace( "'%s'", '%s', $query ); // in case someone mistakenly already singlequoted it
		$query = str_replace( '"%s"', '%s', $query ); // doublequote unquoting
		$query = preg_replace( '|(?<!%)%f|' , '%F', $query ); // Force floats to be locale unaware
		$query = preg_replace( '|(?<!%)%s|', "'%s'", $query ); // quote the strings, avoiding escaped strings like %%s
		array_walk( $args, array( $this, 'escape_by_ref' ) );
		return @vsprintf( $query, $args );
	}



	public function escape_by_ref( &$string ) {
		if ( ! is_float( $string ) )
			$string = $this->_real_escape( $string );
	}



	function _real_escape( $string ) {
		if ( $this->use_mysqli ) {
			return mysqli_real_escape_string( $this->dbh, $string );
		} else {
			return mysql_real_escape_string( $string, $this->dbh );
		}
	}



	public function get_row( $query = null ) {
		$y = 0;

		if ( $query ) {
			$this->query( $query );
		} else {
			return null;
		}

		if ( !isset( $this->last_result[$y] ) )
			return null;

		return $this->last_result[$y] ? $this->last_result[$y] : null;
	}



	public function query( $query ) {
		if ( ! $this->ready ) {
			return false;
		}
		$this->_do_query( $query );
		// If there is an error then take note of it.
		if ( $this->use_mysqli ) {
			if ( $this->dbh instanceof \mysqli ) {
				$this->last_error = mysqli_error( $this->dbh );
			} else {
				$this->last_error = 'query: Unable to retrieve the error message from MySQL';
			}
		} else {
			if ( is_resource( $this->dbh ) ) {
				$this->last_error = mysql_error( $this->dbh );
			} else {
				$this->last_error = 'query: Unable to retrieve the error message from MySQL';
			}
		}

		if ( $this->last_error ) {
			if ( WP_DEBUG ) {
				echo $this->last_error;
			}
			return false;
		}

		$num_rows = 0;
		$this->last_result = array();
		if ( $this->use_mysqli && $this->result instanceof \mysqli_result ) {
			while ( $row = mysqli_fetch_object( $this->result ) ) {
				$this->last_result[$num_rows] = $row;
				$num_rows++;
			}
		} elseif ( is_resource( $this->result ) ) {
			while ( $row = mysql_fetch_object( $this->result ) ) {
				$this->last_result[$num_rows] = $row;
				$num_rows++;
			}
		}

		// Log number of rows the query returned
		// and return number of rows selected
		$this->num_rows = $num_rows;
		$return_val     = $num_rows;

		return $return_val;
	}

	private function _do_query( $query ) {
		if ( ! empty( $this->dbh ) && $this->use_mysqli ) {
			$this->result = mysqli_query( $this->dbh, $query );
		} elseif ( ! empty( $this->dbh ) ) {
			$this->result = mysql_query( $query, $this->dbh );
		}
	}



	public function close() {
		if ( ! $this->dbh ) {
			return false;
		}

		if ( $this->use_mysqli ) {
			$closed = mysqli_close( $this->dbh );
		} else {
			$closed = mysql_close( $this->dbh );
		}

		if ( $closed ) {
			$this->dbh = null;
			$this->ready = false;
			$this->has_connected = false;
		}

		return $closed;
	}
}
