U
    8ÄT_À  ã                   @   sR   d Z ddlmZmZ G dd„ deƒZG dd„ dƒZG dd„ dƒZG d	d
„ d
ƒZdS )z]
Useful auxiliary data structures for query construction. Not useful outside
the SQL domain.
é    )ÚINNERÚLOUTERc                   @   s   e Zd ZdZdd„ ZdS )Ú	MultiJoinz¤
    Used by join construction code to indicate the point at which a
    multi-valued join was attempted (if the caller wants to treat that
    exceptionally).
    c                 C   s   || _ || _d S ©N)ÚlevelZnames_with_path)ÚselfZ	names_posZpath_with_names© r   úG/tmp/pip-unpacked-wheel-dv63caxw/django/db/models/sql/datastructures.pyÚ__init__   s    zMultiJoin.__init__N)Ú__name__Ú
__module__Ú__qualname__Ú__doc__r
   r   r   r   r	   r      s   r   c                   @   s   e Zd ZdS )ÚEmptyN)r   r   r   r   r   r   r	   r      s   r   c                   @   sJ   e Zd ZdZddd„Zdd„ Zdd„ Zd	d
„ Zdd„ Zdd„ Z	dd„ Z
dS )ÚJoinaÙ  
    Used by sql.Query and sql.SQLCompiler to generate JOIN clauses into the
    FROM entry. For example, the SQL generated could be
        LEFT OUTER JOIN "sometable" T1 ON ("othertable"."sometable_id" = "sometable"."id")

    This class is primarily used in Query.alias_map. All entries in alias_map
    must be Join compatible by providing the following attributes and methods:
        - table_name (string)
        - table_alias (possible alias for the table, can be None)
        - join_type (can be None for those entries that aren't joined from
          anything)
        - parent_alias (which table is this join's parent, can be None similarly
          to join_type)
        - as_sql()
        - relabeled_clone()
    Nc                 C   s8   || _ || _|| _|| _| ¡ | _|| _|| _|| _d S r   )	Ú
table_nameÚparent_aliasÚtable_aliasÚ	join_typeZget_joining_columnsÚ	join_colsÚ
join_fieldÚnullableÚfiltered_relation)r   r   r   r   r   r   r   r   r   r   r	   r
   )   s    
zJoin.__init__c              	   C   s,  g }g }|j }|jj}| jD ]2\}}| d|| jƒ||ƒ|| jƒ||ƒf ¡ q| j |j	j
| j| j¡}	|	r’| |	¡\}
}| d|
 ¡ | |¡ | jrÄ| | j¡\}
}|
rÄ| d|
 ¡ | |¡ |sæt| jd| jƒ}td|j ƒ‚d |¡}| j| jk�rdnd| j }d| j|| jƒ||f }||fS )	z™
        Generate the full
           LEFT OUTER JOIN sometable ON sometable.somecol = othertable.othercol, params
        clause for this join.
        z%s.%s = %s.%sz(%s)ÚfieldzaJoin generated an empty ON clause. %s did not yield either joining columns or extra restrictions.z AND Ú ú %sz%s %s%s ON (%s))Úquote_name_unless_aliasÚopsZ
quote_namer   Úappendr   r   r   Zget_extra_restrictionÚqueryZwhere_classÚcompileÚextendr   ÚgetattrÚ
ValueErrorÚ	__class__Újoinr   r   )r   ÚcompilerÚ
connectionZjoin_conditionsÚparamsÚqnZqn2Zlhs_colZrhs_colZ
extra_condZ	extra_sqlZextra_paramsZdeclared_fieldZon_clause_sqlÚ	alias_strZsqlr   r   r	   Úas_sql;   sH    ü
	  ÿ

ÿÿ
zJoin.as_sqlc              	      sr   ˆ   | j| j¡}ˆ   | j| j¡}| jd k	rN| j ¡ }‡ fdd„| jjD ƒ|_nd }| j| j||| j| j	| j
|d�S )Nc                    s   g | ]}ˆ   ||¡‘qS r   )Úget)Ú.0Úp©Ú
change_mapr   r	   Ú
<listcomp>m   s     z(Join.relabeled_clone.<locals>.<listcomp>)r   )r,   r   r   r   ÚcloneÚpathr$   r   r   r   r   )r   r0   Znew_parent_aliasZnew_table_aliasr   r   r/   r	   Úrelabeled_cloneh   s    

     þzJoin.relabeled_clonec                 C   sB   t || jƒo@| j|jko@| j|jko@| j|jko@| p@| j|jkS r   )Ú
isinstancer$   r   r   r   r   ©r   ÚotherÚwith_filtered_relationr   r   r	   Úequalsu   s    
ÿ
þ
ýûzJoin.equalsc                 C   s   | j |dd�S )NT)r8   )r9   )r   r7   r   r   r	   Ú__eq__~   s    zJoin.__eq__c                 C   s   |   i ¡}t|_|S r   )r4   r   r   ©r   Únewr   r   r	   Údemote�   s    
zJoin.demotec                 C   s   |   i ¡}t|_|S r   )r4   r   r   r;   r   r   r	   Úpromote†   s    
zJoin.promote)N)r   r   r   r   r
   r+   r4   r9   r:   r=   r>   r   r   r   r	   r      s    ÿ
-	r   c                   @   s<   e Zd ZdZdZdZdZdd„ Zdd„ Zdd„ Z	d	d
„ Z
dS )Ú	BaseTablezÂ
    The BaseTable class is used for base table references in FROM clause. For
    example, the SQL "foo" in
        SELECT * FROM "foo" WHERE somecond
    could be generated by this class.
    Nc                 C   s   || _ || _d S r   )r   r   )r   r   Úaliasr   r   r	   r
   —   s    zBaseTable.__init__c                 C   s2   | j | jkrdnd| j  }| | j¡}|| g fS )Nr   r   )r   r   r   )r   r&   r'   r*   Zbase_sqlr   r   r	   r+   ›   s    zBaseTable.as_sqlc                 C   s   |   | j| | j| j¡¡S r   )r$   r   r,   r   )r   r0   r   r   r	   r4       s    zBaseTable.relabeled_clonec                 C   s$   t | |jƒo"| j|jko"| j|jkS r   )r5   r$   r   r   r6   r   r   r	   r9   £   s
    
ÿ
ýzBaseTable.equals)r   r   r   r   r   r   r   r
   r+   r4   r9   r   r   r   r	   r?   Œ   s   r?   N)	r   Zdjango.db.models.sql.constantsr   r   Ú	Exceptionr   r   r   r?   r   r   r   r	   Ú<module>   s
   t