SDO.php

<?php

class SDO {

	private $pdo;

	function __construct(PDO $pdo) {
		$this->pdo = $pdo;
	}

	function pdo() {
		return $this->pdo;
	}

	function execute($sql, $args = array()) {
		$pdo = $this->pdo;
		$statement = $pdo->prepare($sql);
		$error = $pdo->errorInfo();
		if($error[0] != '00000') {
			throw new Exception($error[2]);
		}
		$statement->execute($args);;
		$error = $pdo->errorInfo();
		if($error[0] != '00000') {
			throw new Exception($error[2]);
		}
		return $statement;
	}

	function cell($sql, $args = array()) {
		return $this->execute($sql, $args)->fetchColumn();
	}

	function row($sql, $args = array(), $class = 'stdClass', $ctorArgs = array()) {
		return $this->execute($sql, $args)->fetchObject($class, $ctorArgs);
	}

	function rows($sql, $args = array(), $class = 'stdClass', $ctorArgs = array()) {
		return $this->execute($sql, $args)->fetchAll(PDO::FETCH_CLASS, $class, $ctorArgs);
	}

	function column($sql, $args = array()) {
		$column = array();
		foreach($this->execute($sql, $args)->fetchAll() as $row) {
			$column []= current($row);
		}
		return $column;
	}

	function insert($table, $row) {
		return $this->execute('INSERT INTO ' . $table . ' (' . implode(', ', array_keys($row)) . ') VALUES (' . implode(', ', array_fill(0, count($row), '?')) . ')', array_values($row))->rowCount();
	}

	function update($table, $row, $keys) {
		return $this->execute('UPDATE ' . $table . ' SET ' . implode(' = ?, ', array_keys($row)) . ' = ? WHERE ' . implode(' = ?, ', array_keys($keys)) . ' = ?', array_merge(array_values($row), array_values($keys)))->rowCount();
	}

	function delete($table, $keys) {
		return $this->execute('DELETE FROM ' . $table . ' WHERE ' . implode(' = ?, ', array_keys($keys)) . ' = ?', array_values($keys))->rowCount();
	}

	function lastId() {
		return $this->pdo->lastInsertId();
	}

	function begin() {
		$this->pdo->beginTransaction();
		return $this;
	}

	function commit() {
		$this->pdo->commit();
		return $this;
	}

	function rollBack() {
		$this->pdo->rollBack();
		return $this;
	}

	function __get($name) {
		return new SDORowSet($this, $name);
	}
}

class SDORowSet implements IteratorAggregate {

	private $sdo;
	private $table;
	private $parentKey;
	private $parentValue;
	private $select;
	private $where;
	private $group;
	private $having;
	private $order;
	private $limit;
	private $offset;
	private $args;

	function __construct(SDO $sdo, $table, $parentKey = NULL, $parentValue = NULL) {
		$this->sdo         = $sdo;
		$this->table       = $table;
		$this->parentKey   = $parentKey;
		$this->parentValue = $parentValue;
	}

	function sdo() {
		return $this->sdo;
	}

	function table() {
		return $this->table;
	}

	function parentKey() {
		return $this->parentKey;
	}

	function parentValue() {
		return $this->parentValue;
	}

	function select($select = NULL) {
		if(func_num_args()) {
			$this->select = $select;
			return $this;
		}
		return $this->select;
	}

	function where($where = NULL, $args = NULL) {
		switch(func_num_args()) {
			case 0:
				return $this->where;
			case 1:
				$this->where = $where;
				return $this;
			case 2:
				$this->where = $where;
				$this->args = $args;
				return $this;
		}
	}

	function group($group = NULL) {
		if(func_num_args()) {
			$this->group = $group;
			return $this;
		}
		return $this->group;
	}

	function having($having = NULL) {
		if(func_num_args()) {
			$this->having = $having;
			return $this;
		}
		return $this->having;
	}

	function order($order = NULL) {
		if(func_num_args()) {
			$this->order = $order;
			return $this;
		}
		return $this->order;
	}

	function limit($limit = NULL) {
		if(func_num_args()) {
			$this->limit = $limit;
			return $this;
		}
		return $this->limit;
	}

	function offset($offset = NULL) {
		if(func_num_args()) {
			$this->offset = $offset;
			return $this;
		}
		return $this->offset;
	}

	function args($args = NULL) {
		if(func_num_args()) {
			$this->args = $args;
			return $this;
		}
		if(is_null($this->args)) {
			$this->args = array();
		}
		return $this->args;
	}

	private function sql() {
		$sql = 'SELECT ';
		if(!is_null($this->select)) {
			$sql .= $this->select;
		} else {
			$sql .= '*';
		}
		$sql .= ' FROM ' . $this->table . ' WHERE 1';
		if($this->parentKey) {
			$sql .= ' AND ' . $this->parentKey . ' = ' . $this->parentValue;
		}
		if(!is_null($this->where)) {
			$sql .= ' AND (' . $this->where . ')';
		}
		if(!is_null($this->group)) {
			$sql .= ' GROUP BY ' . $this->group;
		}
		if(!is_null($this->having)) {
			$sql .= ' HAVING ' . $this->having;
		}
		if(!is_null($this->order)) {
			$sql .= ' ORDER BY ' . $this->order;
		}
		if(!is_null($this->limit)) {
			$sql .= ' LIMIT ' . $this->limit;
			if(!is_null($this->offset)) {
				$sql .= ' OFFSET ' . $this->offset;
			}
		}
		return $sql;
	}

	function count() {
		$sql = 'SELECT COUNT(*) FROM ' . $this->table . ' WHERE 1';
		if($this->parentKey) {
			$sql .= ' AND ' . $this->parentKey . ' = ' . $this->parentValue;
		}
		if(!is_null($this->where)) {
			$sql .= ' AND (' . $this->where . ')';
		}
		if(!is_null($this->group)) {
			$sql .= ' GROUP BY ' . $this->group;
		}
		if(!is_null($this->having)) {
			$sql .= ' HAVING ' . $this->having;
		}
		return $this->sdo->cell($sql, $this->args());
	}

	function exists() {
		$sql = 'SELECT 1 FROM ' . $this->table . ' WHERE 1';
		if($this->parentKey) {
			$sql .= ' AND ' . $this->parentKey . ' = ' . $this->parentValue;
		}
		if(!is_null($this->where)) {
			$sql .= ' AND (' . $this->where . ')';
		}
		if(!is_null($this->group)) {
			$sql .= ' GROUP BY ' . $this->group;
		}
		if(!is_null($this->having)) {
			$sql .= ' HAVING ' . $this->having;
		}
		return $this->sdo->cell($sql, $this->args()) == 1;
	}

	function row() {
		return $this->sdo->row($this->sql(), $this->args(), 'SDORow', array($this));
	}

	function getIterator() {
		return new ArrayIterator($this->sdo->rows($this->sql(), $this->args(), 'SDORow', array($this)));
	}
}

class SDORow {

	private $rowSet;

	function __construct(SDORowSet $rowSet) {
		$this->rowSet = $rowSet;
	}

	function rowSet() {
		return $this->rowSet;
	}

	private function primaryKey($table) {
		foreach($this->rowSet->sdo()->rows('PRAGMA table_info(' . $table . ')') as $row) {
			if($row->pk) {
				return $row->name;
			}
		}
		throw new Exception('Primary key not found.');
	}

	function parent($table, $reference = NULL) {
		$primaryKey = $this->primaryKey($table);
		if(is_null($reference)) {
			$reference = $primaryKey;
		}
		$rowSet = new SDORowSet($this->rowSet->sdo(), $table, $primaryKey, $this->{$reference});
		return $rowSet->row();
	}

	function child($table, $reference = NULL) {
		$primaryKey = $this->primaryKey($this->rowSet->table());
		if(is_null($reference)) {
			$reference = $primaryKey;
		}
		return new SDORowSet($this->rowSet->sdo(), $table, $reference, $this->{$primaryKey});
	}

	private function tableExists($name) {
		return $this->rowSet->sdo()->cell("SELECT 1 FROM sqlite_master WHERE type = 'table' AND name = '$name'") == 1;
	}

	private function tableByPrimaryKey($primaryKey) {
		foreach($this->rowSet->sdo()->rows("SELECT name FROM sqlite_master WHERE type = 'table'") as $row) {
			foreach($this->rowSet->sdo()->rows('PRAGMA table_info(' . $row->name . ')') as $row2) {
				if($row2->name == $primaryKey && $row2->pk) {
					return $row->name;
				}
			}
		}
		throw new Exception('Table not found.');
	}

	function __get($name) {
		if($this->tableExists($name)) {
			return $this->child($name);
		}
		if(isset($this->{$name . '_id'})) {
			return $this->parent($this->tableByPrimaryKey($name . '_id'));
		}
		throw new Exception('Property not found.');
	}
}