<?php

namespace PragmaRX\Sqli\Support;


class Completer {

	/**
	 * @var Options
	 */
	private $options;

	/**
	 * List of all SQL commands.
	 *
	 * @var array
	 */
	private $sqlWords = array
	(
		'SELECT', 'FROM', 'WHERE', 'SET', 'ORDER BY', 'GROUP BY', 'LIMIT', 'DROP',
		'VALUES', 'UPDATE', 'HAVING', 'ADD', 'AFTER', 'ALTER TABLE', 'DELETE FROM', 'UNION ALL', 'UNION', 'EXCEPT', 'INTERSECT',

		'LEFT OUTER JOIN', 'RIGHT OUTER JOIN', 'LEFT JOIN', 'RIGHT JOIN', 'OUTER JOIN', 'INNER JOIN', 'JOIN', 'XOR', 'OR', 'AND',

		'ABS', 'ACOS', 'ADDDATE', 'ADDTIME', 'AES_DECRYPT', 'AES_ENCRYPT', 'AREA', 'ASBINARY', 'ASCII', 'ASIN', 'ASTEXT', 'ATAN', 'ATAN2',
		'AVG', 'BDMPOLYFROMTEXT',  'BDMPOLYFROMWKB', 'BDPOLYFROMTEXT', 'BDPOLYFROMWKB', 'BENCHMARK', 'BIN', 'BIT_AND', 'BIT_COUNT', 'BIT_LENGTH',
		'BIT_OR', 'BIT_XOR', 'BOUNDARY',  'BUFFER',  'CAST', 'CEIL', 'CEILING', 'CENTROID',  'CHAR', 'CHARACTER_LENGTH', 'CHARSET', 'CHAR_LENGTH',
		'COALESCE', 'COERCIBILITY', 'COLLATION',  'COMPRESS', 'CONCAT', 'CONCAT_WS', 'CONNECTION_ID', 'CONTAINS', 'CONV', 'CONVERT', 'CONVERT_TZ',
		'CONVEXHULL',  'COS', 'COT', 'COUNT', 'CRC32', 'CROSSES', 'CURDATE', 'CURRENT_DATE', 'CURRENT_TIME', 'CURRENT_TIMESTAMP', 'CURRENT_USER',
		'CURTIME', 'DATABASE', 'DATE', 'DATEDIFF', 'DATE_ADD', 'DATE_DIFF', 'DATE_FORMAT', 'DATE_SUB', 'DAY', 'DAYNAME', 'DAYOFMONTH', 'DAYOFWEEK',
		'DAYOFYEAR', 'DECODE', 'DEFAULT', 'DEGREES', 'DES_DECRYPT', 'DES_ENCRYPT', 'DIFFERENCE', 'DIMENSION', 'DISJOINT', 'DISTANCE', 'ELT', 'ENCODE',
		'ENCRYPT', 'ENDPOINT', 'ENVELOPE', 'EQUALS', 'EXP', 'EXPORT_SET', 'EXTERIORRING', 'EXTRACT', 'EXTRACTVALUE', 'FIELD', 'FIND_IN_SET', 'FLOOR',
		'FORMAT', 'FOUND_ROWS', 'FROM_DAYS', 'FROM_UNIXTIME', 'GEOMCOLLFROMTEXT', 'GEOMCOLLFROMWKB', 'GEOMETRYCOLLECTION', 'GEOMETRYCOLLECTIONFROMTEXT',
		'GEOMETRYCOLLECTIONFROMWKB', 'GEOMETRYFROMTEXT', 'GEOMETRYFROMWKB', 'GEOMETRYN', 'GEOMETRYTYPE', 'GEOMFROMTEXT', 'GEOMFROMWKB', 'GET_FORMAT',
		'GET_LOCK', 'GLENGTH', 'GREATEST', 'GROUP_CONCAT', 'GROUP_UNIQUE_USERS', 'HEX', 'HOUR', 'IF', 'IFNULL', 'INET_ATON', 'INET_NTOA', 'INSERT', 'INSTR',
		'INTERIORRINGN', 'INTERSECTION', 'INTERSECTS',  'INTERVAL', 'ISCLOSED', 'ISEMPTY', 'ISNULL', 'ISRING', 'ISSIMPLE', 'IS_FREE_LOCK', 'IS_USED_LOCK',
		'LAST_DAY', 'LAST_INSERT_ID', 'LCASE', 'LEAST', 'LEFT', 'LENGTH', 'LINEFROMTEXT', 'LINEFROMWKB', 'LINESTRING', 'LINESTRINGFROMTEXT', 'LINESTRINGFROMWKB',
		'LN', 'LOAD_FILE', 'LOCALTIME', 'LOCALTIMESTAMP', 'LOCATE', 'LOG', 'LOG10', 'LOG2', 'LOWER', 'LPAD', 'LTRIM', 'MAKEDATE', 'MAKETIME', 'MAKE_SET',
		'MASTER_POS_WAIT', 'MAX', 'MBRCONTAINS', 'MBRDISJOINT', 'MBREQUAL', 'MBRINTERSECTS', 'MBROVERLAPS', 'MBRTOUCHES', 'MBRWITHIN', 'MD5', 'MICROSECOND',
		'MID', 'MIN', 'MINUTE', 'MLINEFROMTEXT', 'MLINEFROMWKB', 'MOD', 'MONTH', 'MONTHNAME', 'MPOINTFROMTEXT', 'MPOINTFROMWKB', 'MPOLYFROMTEXT', 'MPOLYFROMWKB',
		'MULTILINESTRING', 'MULTILINESTRINGFROMTEXT', 'MULTILINESTRINGFROMWKB', 'MULTIPOINT',  'MULTIPOINTFROMTEXT', 'MULTIPOINTFROMWKB', 'MULTIPOLYGON',
		'MULTIPOLYGONFROMTEXT', 'MULTIPOLYGONFROMWKB', 'NAME_CONST', 'NULLIF', 'NUMGEOMETRIES', 'NUMINTERIORRINGS',  'NUMPOINTS', 'OCT', 'OCTET_LENGTH',
		'OLD_PASSWORD', 'ORD', 'OVERLAPS', 'PASSWORD', 'PERIOD_ADD', 'PERIOD_DIFF', 'PI', 'POINT', 'POINTFROMTEXT', 'POINTFROMWKB', 'POINTN', 'POINTONSURFACE',
		'POLYFROMTEXT', 'POLYFROMWKB', 'POLYGON', 'POLYGONFROMTEXT', 'POLYGONFROMWKB', 'POSITION', 'POW', 'POWER', 'QUARTER', 'QUOTE', 'RADIANS', 'RAND',
		'RELATED', 'RELEASE_LOCK', 'REPEAT', 'REPLACE', 'REVERSE', 'RIGHT', 'ROUND', 'ROW_COUNT', 'RPAD', 'RTRIM', 'SCHEMA', 'SECOND', 'SEC_TO_TIME',
		'SESSION_USER', 'SHA', 'SHA1', 'SIGN', 'SIN', 'SLEEP', 'SOUNDEX', 'SPACE', 'SQRT', 'SRID', 'STARTPOINT', 'STD', 'STDDEV', 'STDDEV_POP', 'STDDEV_SAMP',
		'STRCMP', 'STR_TO_DATE', 'SUBDATE', 'SUBSTR', 'SUBSTRING', 'SUBSTRING_INDEX', 'SUBTIME', 'SUM', 'SYMDIFFERENCE', 'SYSDATE', 'SYSTEM_USER', 'TAN',
		'TIME', 'TIMEDIFF', 'TIMESTAMP', 'TIMESTAMPADD', 'TIMESTAMPDIFF', 'TIME_FORMAT', 'TIME_TO_SEC', 'TOUCHES', 'TO_DAYS', 'TRIM', 'TRUNCATE', 'UCASE',
		'UNCOMPRESS', 'UNCOMPRESSED_LENGTH', 'UNHEX', 'UNIQUE_USERS', 'UNIX_TIMESTAMP', 'UPDATEXML', 'UPPER', 'USER', 'UTC_DATE', 'UTC_TIME', 'UTC_TIMESTAMP',
		'UUID', 'VARIANCE', 'VAR_POP', 'VAR_SAMP', 'VERSION', 'WEEK', 'WEEKDAY', 'WEEKOFYEAR', 'WITHIN', 'X', 'Y', 'YEAR', 'YEARWEEK',

		'ACCESSIBLE', 'ACTION', 'AGAINST', 'AGGREGATE', 'ALGORITHM', 'ALL', 'ALTER', 'ANALYSE', 'ANALYZE', 'AS', 'ASC',
		'AUTOCOMMIT', 'AUTO_INCREMENT', 'BACKUP', 'BEGIN', 'BETWEEN', 'BINLOG', 'BOTH', 'CASCADE', 'CASE', 'CHANGE', 'CHANGED', 'CHARACTER SET',
		'CHARSET', 'CHECK', 'CHECKSUM', 'COLLATE', 'COLLATION', 'COLUMN', 'COLUMNS', 'COMMENT', 'COMMIT', 'COMMITTED', 'COMPRESSED', 'CONCURRENT',
		'CONSTRAINT', 'CONTAINS', 'CONVERT', 'CREATE', 'CROSS', 'CURRENT_TIMESTAMP', 'DATABASE', 'DATABASES', 'DAY', 'DAY_HOUR', 'DAY_MINUTE',
		'DAY_SECOND', 'DEFAULT', 'DEFINER', 'DELAYED', 'DELETE', 'DESC', 'DESCRIBE', 'DETERMINISTIC', 'DISTINCT', 'DISTINCTROW', 'DIV',
		'DO', 'DUMPFILE', 'DUPLICATE', 'DYNAMIC', 'ELSE', 'ENCLOSED', 'END', 'ENGINE', 'ENGINE_TYPE', 'ENGINES', 'ESCAPE', 'ESCAPED', 'EVENTS', 'EXEC',
		'EXECUTE', 'EXISTS', 'EXPLAIN', 'EXTENDED', 'FAST', 'FIELDS', 'FILE', 'FIRST', 'FIXED', 'FLUSH', 'FOR', 'FORCE', 'FOREIGN', 'FULL', 'FULLTEXT',
		'FUNCTION', 'GLOBAL', 'GRANT', 'GRANTS', 'GROUP_CONCAT', 'HEAP', 'HIGH_PRIORITY', 'HOSTS', 'HOUR', 'HOUR_MINUTE',
		'HOUR_SECOND', 'IDENTIFIED', 'IF', 'IFNULL', 'IGNORE', 'IN', 'INDEX', 'INDEXES', 'INFILE', 'INSERT', 'INSERT_ID', 'INSERT_METHOD', 'INTERVAL',
		'INTO', 'INVOKER', 'IS', 'ISOLATION', 'KEY', 'KEYS', 'KILL', 'LAST_INSERT_ID', 'LEADING', 'LEVEL', 'LIKE', 'LINEAR',
		'LINES', 'LOAD', 'LOCAL', 'LOCK', 'LOCKS', 'LOGS', 'LOW_PRIORITY', 'MARIA', 'MASTER', 'MASTER_CONNECT_RETRY', 'MASTER_HOST', 'MASTER_LOG_FILE',
		'MATCH','MAX_CONNECTIONS_PER_HOUR', 'MAX_QUERIES_PER_HOUR', 'MAX_ROWS', 'MAX_UPDATES_PER_HOUR', 'MAX_USER_CONNECTIONS',
		'MEDIUM', 'MERGE', 'MINUTE', 'MINUTE_SECOND', 'MIN_ROWS', 'MODE', 'MODIFY',
		'MONTH', 'MRG_MYISAM', 'MYISAM', 'NAMES', 'NATURAL', 'NOT', 'NOW()','NULL', 'OFFSET', 'ON', 'OPEN', 'OPTIMIZE', 'OPTION', 'OPTIONALLY',
		'ON UPDATE', 'ON DELETE', 'OUTFILE', 'PACK_KEYS', 'PAGE', 'PARTIAL', 'PARTITION', 'PARTITIONS', 'PASSWORD', 'PRIMARY', 'PRIVILEGES', 'PROCEDURE',
		'PROCESS', 'PROCESSLIST', 'PURGE', 'QUICK', 'RANGE', 'RAID0', 'RAID_CHUNKS', 'RAID_CHUNKSIZE','RAID_TYPE', 'READ', 'READ_ONLY',
		'READ_WRITE', 'REFERENCES', 'REGEXP', 'RELOAD', 'RENAME', 'REPAIR', 'REPEATABLE', 'REPLACE', 'REPLICATION', 'RESET', 'RESTORE', 'RESTRICT',
		'RETURN', 'RETURNS', 'REVOKE', 'RLIKE', 'ROLLBACK', 'ROW', 'ROWS', 'ROW_FORMAT', 'SECOND', 'SECURITY', 'SEPARATOR',
		'SERIALIZABLE', 'SESSION', 'SHARE', 'SHOW', 'SHUTDOWN', 'SLAVE', 'SONAME', 'SOUNDS', 'SQL',  'SQL_AUTO_IS_NULL', 'SQL_BIG_RESULT',
		'SQL_BIG_SELECTS', 'SQL_BIG_TABLES', 'SQL_BUFFER_RESULT', 'SQL_CALC_FOUND_ROWS', 'SQL_LOG_BIN', 'SQL_LOG_OFF', 'SQL_LOG_UPDATE',
		'SQL_LOW_PRIORITY_UPDATES', 'SQL_MAX_JOIN_SIZE', 'SQL_QUOTE_SHOW_CREATE', 'SQL_SAFE_UPDATES', 'SQL_SELECT_LIMIT', 'SQL_SLAVE_SKIP_COUNTER',
		'SQL_SMALL_RESULT', 'SQL_WARNINGS', 'SQL_CACHE', 'SQL_NO_CACHE', 'START', 'STARTING', 'STATUS', 'STOP', 'STORAGE',
		'STRAIGHT_JOIN', 'STRING', 'STRIPED', 'SUPER', 'TABLE', 'TABLES', 'TEMPORARY', 'TERMINATED', 'THEN', 'TO', 'TRAILING', 'TRANSACTIONAL', 'TRUE',
		'TRUNCATE', 'TYPE', 'TYPES', 'UNCOMMITTED', 'UNIQUE', 'UNLOCK', 'UNSIGNED', 'USAGE', 'USE', 'USING', 'VARIABLES',
		'VIEW', 'WHEN', 'WITH', 'WORK', 'WRITE', 'YEAR_MONTH'
	);

	private $commands;

	/**
	 * Instantiate a Completer.
	 *
	 * @param Options $options
	 */
	public function __construct(Options $options)
	{
		$this->options = $options;

		$this->configure();
	}

	/**
	 * Generate the completion data.
	 *
	 */
	private function generateCompletionData()
	{
		$this->commands = [];

		$this->commands = array_merge($this->commands, $this->sqlWords);

		$this->commands = array_unique($this->commands);
	}

	/**
	 * Configure the Completer
	 */
	private function configure()
	{
		$this->generateCompletionData();

		$me = $this;

		readline_completion_function(function($input, $index) use ($me)
		{
			return $this->completer($input, $index);
		});
	}

	/**
	 * Completer callback.
	 *
	 * @param $input
	 * @param $index
	 * @return array
	 */
	public function completer($input, $index)
	{
		$matches = array();

		foreach ($this->commandsThatBeginWith($input) as $phrase)
		{
			$matches[] = $phrase;
		}

		return $matches ?: array($input);
	}

	/**
	 * Get a list of commands which begins with a string.
	 *
	 * @param $input
	 * @return array
	 */
	private function commandsThatBeginWith($input)
	{
		$commands = array();

		$isLower = ctype_lower(preg_replace("/[^a-zA-Z]+/", "", $input));

		foreach($this->commands as $command)
		{
			if (starts_with(strtoupper($command), strtoupper($input)))
			{
				$commands[] = $isLower
								? strtolower($command)
								: strtoupper($command);
			}
		}

		return $commands;
	}

	public function addCommands($names)
	{
		foreach ($names as $command)
		{
			if ( ! in_array($command, $this->commands))
			{
				$this->commands[] = $command;
			}
		}
	}

}
