<?php

/**
 * 公共模型类
 */

namespace base;

class Model {

    /**
     * 模型配置
     * @var array
     */
    protected $config =array();

    /**
     * 操作参数
     * @var array
     */
    protected $options = array(
        'table' => '',
        'field' => '*',
        'where' => array(),
        'order' => '',
        'limit' => '',
        'data' => array(),
        'pager' => array(),
    );

    /**
     * 数据库配置名
     * @var string
     */
    protected $database = 'default';

    /**
     * 操作表
     * @var string
     */
    protected $table = '';	

    /**
     * 当前表
     * @var null
     */
    protected $trueTable = null;

    /**
     * 驱动对象
     * @var array
     */
    protected static $objArr = array();

    /**
     * 分页信息
     * @var null
     */
    public $pager = null;

    /**
     * 初始化
     * @param string $database 模型配置名
     */
    public function __construct( $database = 'default' ) {
        if( $database ){
            $this->database = $database;
        }
        $this->config = Config::get('DB.' . $this->database);
        if( empty($this->config) || !isset($this->config['DB_TYPE']) ) {
            throw new \Exception($this->database.' database config error', 500);
        }
        $this->table = (null==$this->trueTable) ? $this->config['DB_PREFIX'].$this->table : $this->trueTable;
        $this->trueTable = $this->table;
        $this->table($this->trueTable, true);
    }

    /**
     * 执行SQL查询
     * @param  string $sql    SQL语句
     * @param  array  $params 过滤参数
     * @return mixed
     */
    public function query($sql, $params = array()) {
        $sql = trim($sql);
        if ( empty($sql) ) return array();
        $sql = str_replace('{pre}', $this->config['DB_PREFIX'], $sql);
        //判断当前的sql是否是查询语句
        if (stripos(trim($sql), 'show') === 0 || stripos(trim($sql), 'select') === 0 || stripos(trim($sql), 'desc') === 0) {
            return $this->getDb()->query($sql, $params);
        } else {
            return $this->execute($sql, $params); //不是查询条件，直接执行
        }
    }

    /**
     * 执行SQL读写
     * @param  string $sql    SQL语句
     * @param  array  $params 过滤参数
     * @return mixed
     */
    public function execute($sql, $params = array()) {
        $sql = trim($sql);
        if ( empty($sql) ) return 0;
        $sql = str_replace('{pre}', $this->config['DB_PREFIX'], $sql);
        return $this->getDb()->execute($sql, $params); 
    }

    /**
     * 查询一条数据
     * @return array
     */
    public function find() {
        $this->limit(1);
        $data = $this->select();
        return isset($data[0]) ? $data[0] : array();
    }

    /**
     * 查询多条数据
     * @return array
     */
    public function select() {		
        $field = $this->options['field'];
        if( empty($field) ) $field  = '*'; 
        $this->options['field'] = '*';

        $order = $this->options['order'];
        $this->options['order'] = '';

        $limit = $this->options['limit'];
        $this->options['limit'] = '';

        $table = $this->_getTable();
        $where = $this->_getWhere();

        //Pagination
        if( !empty($this->options['pager']) ){
            $count = $this->getDb()->Count($table, $where);
            $this->_pager($this->options['pager']['page'], $this->options['pager']['pageSize'], 
                $this->options['pager']['scope'], $count);
            $this->options['pager'] = array();
            $limit = $this->pager['offset'] . ',' . $this->pager['limit'];
        }

        return $this->getDb()->select($table, $where, $field, $order, $limit);		
    }

    /**
     * 插入数据
     * @return integer
     */
    public function insert() {
        if( empty($this->options['data']) || !is_array($this->options['data']) ) return false;

        return $this->getDb()->insert($this->_getTable(), $this->_getData());
    }

    /**
     * 更新数据
     * @return boolean
     */
    public function update() {
        if( empty($this->options['where']) || !is_array($this->options['where'])  ) return false;
        if( empty($this->options['data']) || !is_array($this->options['data']) ) return false;

        return $this->getDb()->update($this->_getTable(), $this->_getWhere(), $this->_getData());
    }

    /**
     * 删除数据
     * @return boolean
     */
    public function delete() {
        if( empty($this->options['where']) || !is_array($this->options['where'])  ) return false;

        return $this->getDb()->delete($this->_getTable(), $this->_getWhere());
    }

    /**
     * 统计数据
     * @return integer
     */
    public function count() {
        return $this->getDb()->count($this->_getTable(), $this->_getWhere());
    }

    /**
     * 获取表字段
     * @return array
     */
    public function getFields() {
        return $this->getDb()->getFields( $this->_getTable() );
    }

    /**
     * 获取最后查询语句
     * @return string
     */
    public function getSql() {
        return $this->getDb()->getSql();
    }

    /**
     * 启动事务
     * @return boolean
     */
    public function beginTransaction() {
        return $this->getDb()->beginTransaction();
    }

    /**
     * 提交事务
     * @return boolean
     */
    public function commit() {
        return $this->getDb()->commit();
    }

    /**
     * 回滚事务
     * @return boolean
     */
    public function rollBack() {
        return $this->getDb()->rollBack();
    }

    /**
     * 设置表
     * @param  string  $table     表名
     * @param  boolean $ignorePre 独立前缀
     * @return object
     */
    public function table($table, $ignorePre = false) {
        $this->options['table'] = $ignorePre ? $table : $this->config['DB_PREFIX'] . $table;
        return $this;
    }

    /**
     * 联操作表
     * @param  string $join 联接表语句
     * @param  string $way  联接类型
     * @return object
     */
    public function join($join, $way='inner') {
        $join = str_replace('{pre}', $this->config['DB_PREFIX'], $join);
        $this->options['table'] = " {$this->options['table']} {$way} join {$join} ";
        return $this;
    }

    /**
     * 查询字段
     * @param  string $field 查询表指定字段
     * @return object
     */
    public function field($field) {
        $this->options['field'] = $field;
        return $this;
    }

    /**
     * 操作数据
     * @param  array  $data 插入或者更新数据数组
     * @return object
     */
    public function data(array $data = array()) {
        $this->options['data'] = $data;
        return $this;
    }

    /**
     * 查询条件
     * @param  array  $where 条件数组
     * @return object
     */
    public function where(array $where = array()) {
        $this->options['where'] = $where;
        return $this;
    }		

    /**
     * 排序规则
     * @param  string $order 查询结果排序
     * @return object
     */
    public function order($order) {
        $this->options['order'] = $order;
        return $this;
    }

    /**
     * 查询数量
     * @param  integer $limit 查询结果数量
     * @return object
     */
    public function limit($limit) {
        $this->options['limit'] = $limit;
        return $this;
    }	

    /**
     * 查询分页
     * @param  integer $page     当前页数
     * @param  integer $pageSize 每页数量
     * @param  integer $scope    页数范围
     * @return object
     */
    public function pager($page, $pageSize = 10, $scope = 10) {
        $page = max(intval($page), 1);
        $this->options['pager'] = compact(array('page', 'pageSize', 'scope'));
        return $this;
    }

    /**
     * 查询缓存
     * @param  integer $expire 缓存时间：秒
     * @return boolean
     */
    public function cache($expire = 1800) {
        $cache = new Cache($this->config['DB_CACHE']);
        $cache->proxyObj = $this;
        $cache->proxyExpire = $expire;
        return $cache;
    }

    /**
     * 清空缓存
     * @return boolean
     */
    public function clear() {
        $cache = new Cache($this->config['DB_CACHE']);
        return $cache->clear();
    }

    /**
     * 获取驱动对象
     * @return object
     */
    protected function getDb() {
        if( empty(self::$objArr[$this->database]) ){
            $dbDriver = __NAMESPACE__.'\db\\' . ucfirst( $this->config['DB_TYPE'] ).'Driver';
            self::$objArr[$this->database] = new $dbDriver( $this->config );
        }
        return self::$objArr[$this->database];
    }

    /**
     * 获取表名
     * @return string
     */
    protected function _getTable() {
        $table = $this->options['table'];
        $this->options['table'] = $this->table;
        return $table;
    }

    /**
     * 获取条件
     * @return array
     */
    protected function _getWhere() {
        $where = $this->options['where'];
        $this->options['where']= array();	
        return $where;
    }

    /**
     * 获取数据
     * @return array
     */
    protected function _getData() {
        $data = $this->options['data'];
        $this->options['data']= array();
        return $data;
    }

    /**
     * 设置分页
     * @return void
     */
    protected function _pager($page, $pageSize = 10, $scope = 10, $total) {		
        $page = max(intval($page), 1);
        $totalPage = ceil( $total / $pageSize );

        $this->pager = array(		
            'page'=> $page,			
            'pageSize'   => $pageSize,
            'scope'   => $scope,
            'totalPage'  => $totalPage,
            'totalCount' => $total,
            'firstPage'  => 1,
            'prevPage'   => ( ( 1 == $page ) ? 1 : ($page - 1) ),
            'nextPage'   => ( ( $page == $totalPage ) ? $totalPage : ($page + 1)),
            'lastPage'   => $totalPage,			
            'allPages'   => array(),
            'offset'      => ($page - 1) * $pageSize,
            'limit'       => $pageSize,
        );

        if($totalPage <= $scope ){
            $this->pager['allPages'] = range(1, $totalPage);
        }elseif( $page <= $scope/2) {
            $this->pager['allPages'] = range(1, $scope);
        }elseif( $page <= $totalPage - $scope/2 ){
            $right = $page + (int)($scope/2);
            $this->pager['allPages'] = range($right-$scope+1, $right);
        }else{
            $this->pager['allPages'] = range($totalPage-$scope+1, $totalPage);
        }
    }
}