<?php namespace App\Servers\Data;

/**
 * 树形栏目
 * 
 */
class Tree {

    /**
     * 返回多层栏目
     *
     * @param $data 操作的数组
     * @param int $pid 一级PID的值
     * @param string $html 栏目名称前缀
     * @param string $fieldPri 唯一键名，如果是表则是表的主键
     * @param string $fieldPid 父ID键名
     * @param int $level 不需要传参数（执行时调用）
     *
     * @return array
     */
    public function channelLevel( $data, $pid = 0, $html = "&nbsp;", $fieldPri = 'cid', $fieldPid = 'pid', $level = 1 ) {
        if ( empty( $data ) ) {
            return [ ];
        }
        $arr = [ ];
        foreach ( $data as $v ) {
            if ( $v[ $fieldPid ] == $pid ) {
                $arr[ $v[ $fieldPri ] ]           = $v;
                $arr[ $v[ $fieldPri ] ]['_level'] = $level;
                $arr[ $v[ $fieldPri ] ]['_html']  = str_repeat( $html, $level - 1 );
                $arr[ $v[ $fieldPri ] ]["_data"]  = $this->channelLevel( $data, $v[ $fieldPri ], $html, $fieldPri, $fieldPid, $level + 1 );
            }
        }

        return $arr;
    }

    /**
     * 获得所有子栏目
     *
     * @param $data 栏目数据
     * @param int $pid 操作的栏目
     * @param string $html 栏目名前字符
     * @param string $fieldPri 表主键
     * @param string $fieldPid 父id
     * @param int $level 等级
     *
     * @return array
     */
    public static function channelList( $data, $pid = 0, $html = "&nbsp;", $fieldPri = 'cid', $fieldPid = 'pid', $level = 1 ) {
        $data = Tree::_channelList( $data, $pid, $html, $fieldPri, $fieldPid, $level );
        if ( empty( $data ) ) {
            return $data;
        }
        foreach ( $data as $n => $m ) {
            if ( $m['_level'] == 1 ) {
                continue;
            }
            $data[ $n ]['_first'] = FALSE;
            $data[ $n ]['_end']   = FALSE;
            if ( ! isset( $data[ $n - 1 ] ) || $data[ $n - 1 ]['_level'] != $m['_level'] ) {
                $data[ $n ]['_first'] = TRUE;
            }
            if ( isset( $data[ $n + 1 ] ) && $data[ $n ]['_level'] > $data[ $n + 1 ]['_level'] ) {
                $data[ $n ]['_end'] = TRUE;
            }
        }
        //更新key为栏目主键
        $category = [ ];
        foreach ( $data as $d ) {
            $category[ $d[ $fieldPri ] ] = $d;
        }

        return $category;
    }

    //只供channelList方法使用
    public static function _channelList( $data, $pid = 0, $html = "&nbsp;", $fieldPri = 'cid', $fieldPid = 'pid', $level = 1 ) {
        if ( empty( $data ) ) {
            return [ ];
        }
        $arr = [ ];
        foreach ( $data as $v ) {
            $id = $v[ $fieldPri ];
            if ( $v[ $fieldPid ] == $pid ) {
                $v['_level'] = $level;
                $v['_html']  = str_repeat( $html, $level - 1 );
                array_push( $arr, $v );
                $tmp = Tree::_channelList( $data, $id, $html, $fieldPri, $fieldPid, $level + 1 );
                $arr = array_merge( $arr, $tmp );
            }
        }

        return $arr;
    }

    /**
     * 获得树状数据
     *
     * @param $data 数据
     * @param $title 字段名
     * @param string $fieldPri 主键id
     * @param string $fieldPid 父id
     *
     * @return array
     */
    public static function tree( $data, $title, $fieldPri = 'cid', $fieldPid = 'pid' ) {
        if ( ! is_array( $data ) || empty( $data ) ) {
            return [ ];
        }
        $arr = Tree::channelList( $data, 0, '', $fieldPri, $fieldPid );
        foreach ( $arr as $k => $v ) {
            $str = "";
            if ( $v['_level'] > 2 ) {
                for ( $i = 1;$i < $v['_level'] - 1;$i ++ ) {
                    $str .= "│&nbsp;&nbsp;&nbsp;&nbsp;";
                }
            }
            if ( $v['_level'] != 1 ) {
                $t = $title ? $v[ $title ] : '';
                if ( isset( $arr[ $k + 1 ] ) && $arr[ $k + 1 ]['_level'] >= $arr[ $k ]['_level'] ) {
                    $arr[ $k ][ '_' . $title ] = $str . "&nbsp;&nbsp;├─ " . $v['_html'] . $t;
                } else {
                    $arr[ $k ][ '_' . $title ] = $str . "&nbsp;&nbsp;└─ " . $v['_html'] . $t;
                }
            } else {
                $arr[ $k ][ '_' . $title ] = $v[ $title ];
            }
        }
        //设置主键为$fieldPri
        $data = [ ];
        foreach ( $arr as $d ) {
            //            $data[$d[$fieldPri]] = $d;
            $data[] = $d;
        }

        return $data;
    }

    /**
     * 获得所有父级栏目
     *
     * @param $data 栏目数据
     * @param $sid 子栏目
     * @param string $fieldPri 唯一键名，如果是表则是表的主键
     * @param string $fieldPid 父ID键名
     *
     * @return array
     */
    public function parentChannel( $data, $sid, $fieldPri = 'cid', $fieldPid = 'pid' ) {
        if ( empty( $data ) ) {
            return $data;
        } else {
            $arr = [ ];
            foreach ( $data as $v ) {
                if ( $v[ $fieldPri ] == $sid ) {
                    $arr[] = $v;
                    $_n    = $this->parentChannel( $data, $v[ $fieldPid ], $fieldPri, $fieldPid );
                    if ( ! empty( $_n ) ) {
                        $arr = array_merge( $arr, $_n );
                    }
                }
            }

            return $arr;
        }
    }

    /**
     * 判断$s_cid是否是$d_cid的子栏目
     *
     * @param $data 栏目数据
     * @param $sid 子栏目id
     * @param $pid 父栏目id
     * @param string $fieldPri 主键
     * @param string $fieldPid 父id字段
     *
     * @return bool
     */
    private function isChild( $data, $sid, $pid, $fieldPri = 'cid', $fieldPid = 'pid' ) {
        $_data = $this->channelList( $data, $pid, '', $fieldPri, $fieldPid );
        foreach ( $_data as $c ) {
            //目标栏目为源栏目的子栏目
            if ( $c[ $fieldPri ] == $sid ) {
                return TRUE;
            }
        }

        return FALSE;
    }

    /**
     * 检测是不否有子栏目
     *
     * @param $data 栏目数据
     * @param $cid 要判断的栏目cid
     * @param string $fieldPid 父id表字段名
     *
     * @return bool
     */
    private function hasChild( $data, $cid, $fieldPid = 'pid' ) {
        foreach ( $data as $d ) {
            if ( $d[ $fieldPid ] == $cid ) {
                return TRUE;
            }
        }

        return FALSE;
    }

    /**
     * 递归实现迪卡尔乘积
     *
     * @param $arr 操作的数组
     * @param array $tmp
     *
     * @return array
     */
    private function descarte( $arr, $tmp = [ ] ) {
        $n_arr = [ ];
        foreach ( array_shift( $arr ) as $v ) {
            $tmp[] = $v;
            if ( $arr ) {
                $this->descarte( $arr, $tmp );
            } else {
                $n_arr[] = $tmp;
            }
            array_pop( $tmp );
        }

        return $n_arr;
    }

}