<?php
// +----------------------------------------------------------------------
// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]
// +----------------------------------------------------------------------
// | Copyright (c) 2009 http://thinkphp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: liu21st <liu21st@gmail.com>
// +----------------------------------------------------------------------
// $Id$

/**
 +------------------------------------------------------------------------------
 * ThinkPHP 关联模型类
 +------------------------------------------------------------------------------
 * @category   Think
 * @package  Think
 * @subpackage  Core
 * @author    liu21st <liu21st@gmail.com>
 * @version   $Id$
 +------------------------------------------------------------------------------
 */
class RelationModel extends Model {
    // 关联定义
    protected    $_link = array();

    /**
     +----------------------------------------------------------
     * 动态方法实现
     +----------------------------------------------------------
     * @access public
     +----------------------------------------------------------
     * @param string $method 方法名称
     * @param array $args 调用参数
     +----------------------------------------------------------
     * @return mixed
     +----------------------------------------------------------
     */
    public function __call($method,$args) {
        if(strtolower(substr($method,0,8))=='relation'){
            $type    =   strtoupper(substr($method,8));
            if(in_array($type,array('ADD','SAVE','DEL'),true)) {
                array_unshift($args,$type);
                return call_user_func_array(array(&$this, 'opRelation'), $args);
            }
        }else{
            return parent::__call($method,$args);
        }
    }

    /**
     +----------------------------------------------------------
     * 得到关联的数据表名
     +----------------------------------------------------------
     * @access public
     +----------------------------------------------------------
     * @return string
     +----------------------------------------------------------
     */
    public function getRelationTableName($relation)
    {
        $relationTable  = !empty($this->tablePrefix) ? $this->tablePrefix : '';
        $relationTable .= $this->tableName?$this->tableName:$this->name;
        $relationTable .= '_'.$relation->getModelName();
        $relationTable .= !empty($this->tableSuffix) ? $this->tableSuffix : '';
        return strtolower($relationTable);
    }

    // 查询成功后的回调方法
    protected function _after_find(&$result,$options='') {
        // 获取关联数据 并附加到结果中
        if(!empty($options['link']))
            $this->getRelation($result,$options['link']);
    }

    // 查询数据集成功后的回调方法
    protected function _after_select(&$result,$options='') {
        // 获取关联数据 并附加到结果中
        if(!empty($options['link']))
            $this->getRelations($result,$options['link']);
    }

    // 写入成功后的回调方法
    protected function _after_insert(&$data,$options='') {
        // 关联写入
        if(!empty($options['link']))
            $this->opRelation('ADD',$data,$options['link']);
    }

    // 更新成功后的回调方法
    protected function _after_update($data,$options='') {
        // 关联更新
        if(!empty($options['link']))
            $this->opRelation('SAVE',$data,$options['link']);
    }

    // 删除成功后的回调方法
    protected function _after_delete($data,$options) {
        // 关联删除
        if(!empty($options['link']))
            $this->opRelation('DEL',$data,$options['link']);
    }

    /**
     +----------------------------------------------------------
     * 对保存到数据库的数据进行处理
     +----------------------------------------------------------
     * @access protected
     +----------------------------------------------------------
     * @param mixed $data 要操作的数据
     +----------------------------------------------------------
     * @return boolean
     +----------------------------------------------------------
     */
     protected function _facade($data) {
        $this->_before_write($data);
        return $data;
     }

    /**
     +----------------------------------------------------------
     * 获取返回数据集的关联记录
     +----------------------------------------------------------
     * @access protected
     +----------------------------------------------------------
     * @param array $resultSet  返回数据
     * @param string|array $name  关联名称
     +----------------------------------------------------------
     * @return array
     +----------------------------------------------------------
     */
    protected function getRelations(&$resultSet,$name='') {
        // 获取记录集的主键列表
        foreach($resultSet as $key=>$val) {
            $val  = $this->getRelation($val,$name);
            $resultSet[$key]    =   $val;
        }
        return $resultSet;
    }

    /**
     +----------------------------------------------------------
     * 获取返回数据的关联记录
     +----------------------------------------------------------
     * @access protected
     +----------------------------------------------------------
     * @param mixed $result  返回数据
     * @param string|array $name  关联名称
     * @param boolean $return 是否返回关联数据本身
     +----------------------------------------------------------
     * @return array
     +----------------------------------------------------------
     */
    protected function getRelation(&$result,$name='',$return=false)
    {
        if(!empty($this->_link)) {
            foreach($this->_link as $key=>$val) {
                    $mappingName =  !empty($val['mapping_name'])?$val['mapping_name']:$key; // 映射名称
                    if(empty($name) || true === $name || $mappingName == $name || (is_array($name) && in_array($mappingName,$name))) {
                        $mappingType = !empty($val['mapping_type'])?$val['mapping_type']:$val;  //  关联类型
                        $mappingClass  = !empty($val['class_name'])?$val['class_name']:$key;            //  关联类名
                        $mappingFields = !empty($val['mapping_fields'])?$val['mapping_fields']:'*';     // 映射字段
                        $mappingCondition = !empty($val['condition'])?$val['condition']:'1=1';          // 关联条件
                        if(strtoupper($mappingClass)==strtoupper($this->name)) {
                            // 自引用关联 获取父键名
                            $mappingFk   =   !empty($val['parent_key'])? $val['parent_key'] : 'parent_id';
                        }else{
                            $mappingFk   =   !empty($val['foreign_key'])?$val['foreign_key']:strtolower($this->name).'_id';     //  关联外键
                        }
                        // 获取关联模型对象
                        $model = M($mappingClass);
                        switch($mappingType) {
                            case HAS_ONE:
                                $pk   =  $result[$this->getPk()];
                                $mappingCondition .= " AND {$mappingFk}='{$pk}'";
                                $relationData   =  $model->where($mappingCondition)->field($mappingFields)->find();
                                break;
                            case BELONGS_TO:
                                if(strtoupper($mappingClass)==strtoupper($this->name)) {
                                    // 自引用关联 获取父键名
                                    $mappingFk   =   !empty($val['parent_key'])? $val['parent_key'] : 'parent_id';
                                }else{
                                    $mappingFk   =   !empty($val['foreign_key'])?$val['foreign_key']:strtolower($model->getModelName()).'_id';     //  关联外键
                                }
                                $fk   =  $result[$mappingFk];
                                $mappingCondition .= " AND {$model->getPk()}='{$fk}'";
                                $relationData   =  $model->where($mappingCondition)->field($mappingFields)->find();
                                break;
                            case HAS_MANY:
                                $pk   =  $result[$this->getPk()];
                                $mappingCondition .= " AND {$mappingFk}='{$pk}'";
                                $mappingOrder =  !empty($val['mapping_order'])?$val['mapping_order']:'';
                                $mappingLimit =  !empty($val['mapping_limit'])?$val['mapping_limit']:'';
                                // 延时获取关联记录
                                $relationData   =  $model->where($mappingCondition)->field($mappingFields)->order($mappingOrder)->limit($mappingLimit)->select();
                                break;
                            case MANY_TO_MANY:
                                $pk   =  $result[$this->getPk()];
                                $mappingCondition = " {$mappingFk}='{$pk}'";
                                $mappingOrder =  $val['mapping_order'];
                                $mappingLimit =  $val['mapping_limit'];
                                $mappingRelationFk = $val['relation_foreign_key']?$val['relation_foreign_key']:$model->getModelName().'_id';
                                $mappingRelationTable  =  $val['relation_table']?$val['relation_table']:$this->getRelationTableName($model);
                                $sql = "SELECT b.{$mappingFields} FROM {$mappingRelationTable} AS a, ".$model->getTableName()." AS b WHERE a.{$mappingRelationFk} = b.{$model->getPk()} AND a.{$mappingCondition}";
                                if(!empty($val['condition'])) {
                                    $sql   .= ' AND '.$val['condition'];
                                }
                                if(!empty($mappingOrder)) {
                                    $sql .= ' ORDER BY '.$mappingOrder;
                                }
                                if(!empty($mappingLimit)) {
                                    $sql .= ' LIMIT '.$mappingLimit;
                                }
                                $relationData   =   $this->query($sql);
                                break;
                        }
                        if(!$return){
                            if(isset($val['as_fields']) && in_array($mappingType,array(HAS_ONE,BELONGS_TO)) ) {
                                // 支持直接把关联的字段值映射成数据对象中的某个字段
                                // 仅仅支持HAS_ONE BELONGS_TO
                                $fields =   explode(',',$val['as_fields']);
                                foreach ($fields as $field){
                                    if(strpos($field,':')) {
                                        list($name,$nick) = explode(':',$field);
                                        $result[$nick]  =  $relationData[$name];
                                    }else{
                                        $result[$field]  =  $relationData[$field];
                                    }
                                }
                            }else{
                                $result[$mappingName] = $relationData;
                            }
                            unset($relationData);
                        }else{
                            return $relationData;
                        }
                    }
            }
        }
        return $result;
    }

    /**
     +----------------------------------------------------------
     * 操作关联数据
     +----------------------------------------------------------
     * @access protected
     +----------------------------------------------------------
     * @param string $opType  操作方式 ADD SAVE DEL
     * @param mixed $data  数据对象
     * @param string $name 关联名称
     +----------------------------------------------------------
     * @return mixed
     +----------------------------------------------------------
     */
    protected function opRelation($opType,$data='',$name='')
    {
        $result =   false;
        if(empty($data) && !empty($this->data)){
            $data = $this->data;
        }elseif(!is_array($data)){
            // 数据无效返回
            return false;
        }
        if(!empty($this->_link)) {
            // 遍历关联定义
            foreach($this->_link as $key=>$val) {
                    // 操作制定关联类型
                    $mappingName =  $val['mapping_name']?$val['mapping_name']:$key; // 映射名称
                    if(empty($name) || true === $name || $mappingName == $name || (is_array($name) && in_array($mappingName,$name)) ) {
                        // 操作制定的关联
                        $mappingType = !empty($val['mapping_type'])?$val['mapping_type']:$val;  //  关联类型
                        $mappingClass  = !empty($val['class_name'])?$val['class_name']:$key;            //  关联类名
                        // 当前数据对象主键值
                        $pk =   $data[$this->getPk()];
                        if(strtoupper($mappingClass)==strtoupper($this->name)) {
                            // 自引用关联 获取父键名
                            $mappingFk   =   !empty($val['parent_key'])? $val['parent_key'] : 'parent_id';
                        }else{
                            $mappingFk   =   !empty($val['foreign_key'])?$val['foreign_key']:strtolower($this->name).'_id';     //  关联外键
                        }
                        $mappingCondition = !empty($val['condition'])?  $val['condition'] :  "{$mappingFk}='{$pk}'";
                        // 获取关联model对象
                        $model = M($mappingClass);
                        $mappingData    =   isset($data[$mappingName])?$data[$mappingName]:false;
                        if(!empty($mappingData) || $opType == 'DEL') {
                            switch($mappingType) {
                                case HAS_ONE:
                                    switch (strtoupper($opType)){
                                        case 'ADD': // 增加关联数据
                                        $mappingData[$mappingFk]    =   $pk;
                                        $result   =  $model->add($mappingData);
                                        break;
                                        case 'SAVE':    // 更新关联数据
                                        $result   =  $model->where($mappingCondition)->save($mappingData);
                                        break;
                                        case 'DEL': // 根据外键删除关联数据
                                        $result   =  $model->where($mappingCondition)->delete();
                                        break;
                                    }
                                    break;
                                case BELONGS_TO:
                                    break;
                                case HAS_MANY:
                                    switch (strtoupper($opType)){
                                        case 'ADD'   :  // 增加关联数据
                                        $model->startTrans();
                                        foreach ($mappingData as $val){
                                            $val[$mappingFk]    =   $pk;
                                            $result   =  $model->add($val);
                                        }
                                        $model->commit();
                                        break;
                                        case 'SAVE' :   // 更新关联数据
                                        $model->startTrans();
                                        $pk   =  $model->getPk();
                                        foreach ($mappingData as $vo){
                                            if(isset($vo[$pk])) {// 更新数据
                                                $mappingCondition   =  "$pk ={$vo[$pk]}";
                                                $result   =  $model->where($mappingCondition)->save($vo);
                                            }else{ // 新增数据
                                                $vo[$mappingFk] =  $data[$this->getPk()];
                                                $result   =  $model->add($vo);
                                            }
                                        }
                                        $model->commit();
                                        break;
                                        case 'DEL' :    // 删除关联数据
                                        $result   =  $model->where($mappingCondition)->delete();
                                        break;
                                    }
                                    break;
                                case MANY_TO_MANY:
                                    $mappingRelationFk = $val['relation_foreign_key']?$val['relation_foreign_key']:$model->getModelName().'_id';// 关联
                                    $mappingRelationTable  =  $val['relation_table']?$val['relation_table']:$this->getRelationTableName($model);
                                    if(is_array($mappingData)) {
                                        $ids   = array();
                                        foreach ($mappingData as $vo)
                                            $ids[]   =   $vo[$model->getPk()];
                                        $relationId =   implode(',',$ids);
                                    }
                                    switch (strtoupper($opType)){
                                        case 'ADD': // 增加关联数据
                                        case 'SAVE':    // 更新关联数据
                                        if(isset($relationId)) {
                                            $this->startTrans();
                                            // 删除关联表数据
                                            $this->table($mappingRelationTable)->where($mappingCondition)->delete();
                                            // 插入关联表数据
                                            $sql  = 'INSERT INTO '.$mappingRelationTable.' ('.$mappingFk.','.$mappingRelationFk.') SELECT a.'.$this->getPk().',b.'.$model->getPk().' FROM '.$this->getTableName().' AS a ,'.$model->getTableName()." AS b where a.".$this->getPk().' ='. $pk.' AND  b.'.$model->getPk().' IN ('.$relationId.") ";
                                            $result =   $model->execute($sql);
                                            if(false !== $result)
                                                // 提交事务
                                                $this->commit();
                                            else
                                                // 事务回滚
                                                $this->rollback();
                                        }
                                        break;
                                        case 'DEL': // 根据外键删除中间表关联数据
                                        $result =   $this->table($mappingRelationTable)->where($mappingCondition)->delete();
                                        break;
                                    }
                                    break;
                            }
                    }
                }
            }
        }
        return $result;
    }

    /**
     +----------------------------------------------------------
     * 进行关联查询
     +----------------------------------------------------------
     * @access public
     +----------------------------------------------------------
     * @param mixed $name 关联名称
     +----------------------------------------------------------
     * @return Model
     +----------------------------------------------------------
     */
    public function relation($name) {
        $this->options['link']  =   $name;
        return $this;
    }

    /**
     +----------------------------------------------------------
     * 关联数据获取 仅用于查询后
     +----------------------------------------------------------
     * @access public
     +----------------------------------------------------------
     * @param string $name 关联名称
     +----------------------------------------------------------
     * @return array
     +----------------------------------------------------------
     */
    public function relationGet($name) {
        if(empty($this->data))
            return false;
        return $this->getRelation($this->data,$name,true);
    }
}
?>