U
    e                     @   s   d Z ddlmZ G dd dZG dd deZG dd deZG d	d
 d
eZG dd deZG dd deZG dd deZ	G dd deZ
G dd deZdS )z~
Helpers to manipulate deferred DDL statements that might need to be adjusted or
discarded within when executing a migration.
    )deepcopyc                   @   s@   e Zd ZdZdd Zdd Zdd Zdd	 Zd
d Zdd Z	dS )	Referencez0Base class that defines the reference interface.c                 C   s   dS )zU
        Return whether or not this instance references the specified table.
        F selftabler   r   E/tmp/pip-unpacked-wheel-lctamlir/django/db/backends/ddl_references.pyreferences_table   s    zReference.references_tablec                 C   s   dS )zV
        Return whether or not this instance references the specified column.
        Fr   r   r   columnr   r   r   references_column   s    zReference.references_columnc                 C   s   dS )zI
        Rename all references to the old_name to the new_table.
        Nr   r   	old_table	new_tabler   r   r   rename_table_references   s    z!Reference.rename_table_referencesc                 C   s   dS )zL
        Rename all references to the old_column to the new_column.
        Nr   r   r   
old_column
new_columnr   r   r   rename_column_references   s    z"Reference.rename_column_referencesc                 C   s   d| j jt| f S )Nz<%s %r>)	__class____name__strr   r   r   r   __repr__#   s    zReference.__repr__c                 C   s   t dd S )Nz>Subclasses must define how they should be converted to string.)NotImplementedErrorr   r   r   r   __str__&   s    zReference.__str__N)
r   
__module____qualname____doc__r	   r   r   r   r   r   r   r   r   r   r      s   r   c                   @   s0   e Zd ZdZdd Zdd Zdd Zdd	 Zd
S )TablezHold a reference to a table.c                 C   s   || _ || _d S N)r   
quote_name)r   r   r!   r   r   r   __init__/   s    zTable.__init__c                 C   s
   | j |kS r    r   r   r   r   r   r	   3   s    zTable.references_tablec                 C   s   | j |kr|| _ d S r    r#   r   r   r   r   r   6   s    
zTable.rename_table_referencesc                 C   s   |  | jS r    )r!   r   r   r   r   r   r   :   s    zTable.__str__N)r   r   r   r   r"   r	   r   r   r   r   r   r   r   ,   s
   r   c                   @   s(   e Zd ZdZdd Zdd Zdd ZdS )	TableColumnsz9Base class for references to multiple columns of a table.c                 C   s   || _ || _d S r    r   columns)r   r   r&   r   r   r   r"   A   s    zTableColumns.__init__c                 C   s   | j |ko|| jkS r    r%   r
   r   r   r   r   E   s    zTableColumns.references_columnc                 C   s4   | j |kr0t| jD ]\}}||kr|| j|< qd S r    )r   	enumerater&   )r   r   r   r   indexr   r   r   r   r   H   s    
z%TableColumns.rename_column_referencesN)r   r   r   r   r"   r   r   r   r   r   r   r$   >   s   r$   c                       s*   e Zd ZdZd fdd	Zdd Z  ZS )Columnsz(Hold a reference to one or many columns.r   c                    s   || _ || _t || d S r    )r!   col_suffixessuperr"   )r   r   r&   r!   r*   r   r   r   r"   R   s    zColumns.__init__c                    s*   fdd d  fddtjD S )Nc                    sB     | }z j| }|r&d||}W n tk
r<   Y nX |S Nz{} {})r!   r*   format
IndexErrorr   idxcolsuffixr   r   r   col_strX   s    

z Columns.__str__.<locals>.col_str, c                 3   s   | ]\}} ||V  qd S r    r   .0r1   r   r4   r   r   	<genexpr>b   s    z"Columns.__str__.<locals>.<genexpr>joinr'   r&   r   r   r4   r   r   r   W   s    
zColumns.__str__)r   r   r   r   r   r"   r   __classcell__r   r   r,   r   r)   O   s   r)   c                       s(   e Zd ZdZ fddZdd Z  ZS )	IndexNamez"Hold a reference to an index name.c                    s   || _ || _t || d S r    )r3   create_index_namer+   r"   )r   r   r&   r3   r@   r,   r   r   r"   j   s    zIndexName.__init__c                 C   s   |  | j| j| jS r    )r@   r   r&   r3   r   r   r   r   r   o   s    zIndexName.__str__r=   r   r   r,   r   r?   g   s   r?   c                       s&   e Zd Zd fdd	Zdd Z  ZS )IndexColumnsr   c                    s   || _ t |||| d S r    )	opclassesr+   r"   )r   r   r&   r!   r*   rB   r,   r   r   r"   t   s    zIndexColumns.__init__c                    s*   fdd d  fddtjD S )Nc                    sP   d  |  j| }z j| }|r4d ||}W n tk
rJ   Y nX |S r-   )r.   r!   rB   r*   r/   r0   r   r   r   r4   y   s    
z%IndexColumns.__str__.<locals>.col_strr5   c                 3   s   | ]\}} ||V  qd S r    r   r6   r8   r   r   r9      s    z'IndexColumns.__str__.<locals>.<genexpr>r:   r   r   r<   r   r   x   s    zIndexColumns.__str__)r   r   )r   r   r   r"   r   r>   r   r   r,   r   rA   s   s   rA   c                       sX   e Zd ZdZ fddZ fddZ fddZ fdd	Z fd
dZdd Z	  Z
S )ForeignKeyNamez'Hold a reference to a foreign key name.c                    s*   t ||| _|| _|| _t || d S r    )r$   to_referencesuffix_templatecreate_fk_namer+   r"   )r   Z
from_tableZfrom_columnsto_tableZ
to_columnsrE   rF   r,   r   r   r"      s    	zForeignKeyName.__init__c                    s   t  |p| j|S r    )r+   r	   rD   r   r,   r   r   r	      s    zForeignKeyName.references_tablec                    s   t  ||p| j||S r    )r+   r   rD   r
   r,   r   r   r      s     z ForeignKeyName.references_columnc                    s    t  || | j|| d S r    )r+   r   rD   r   r,   r   r   r      s    z&ForeignKeyName.rename_table_referencesc                    s$   t  ||| | j||| d S r    )r+   r   rD   r   r,   r   r   r      s    z'ForeignKeyName.rename_column_referencesc                 C   s.   | j | jj| jjd d }| | j| j|S )Nr   )rG   Z	to_column)rE   rD   r   r&   rF   )r   r3   r   r   r   r      s
    
zForeignKeyName.__str__)r   r   r   r   r"   r	   r   r   r   r   r>   r   r   r,   r   rC      s   rC   c                   @   s@   e Zd ZdZdd Zdd Zdd Zdd	 Zd
d Zdd Z	dS )	Statementz
    Statement template and formatting parameters container.

    Allows keeping a reference to a statement without interpolating identifiers
    that might have to be adjusted if they're referencing a table or column
    that is removed
    c                 K   s   || _ || _d S r    templateparts)r   rJ   rK   r   r   r   r"      s    zStatement.__init__c                    s   t  fdd| j D S )Nc                 3   s"   | ]}t |d o| V  qdS )r	   N)hasattrr	   r7   partr#   r   r   r9      s   z-Statement.references_table.<locals>.<genexpr>anyrK   valuesr   r   r#   r   r	      s    zStatement.references_tablec                    s   t  fdd| j D S )Nc                 3   s$   | ]}t |d o| V  qdS )r   N)rL   r   rM   r   r   r   r   r9      s   z.Statement.references_column.<locals>.<genexpr>rO   r
   r   rR   r   r      s    zStatement.references_columnc                 C   s*   | j  D ]}t|dr
||| q
d S )Nr   )rK   rQ   rL   r   )r   r   r   rN   r   r   r   r      s    
z!Statement.rename_table_referencesc                 C   s,   | j  D ]}t|dr
|||| q
d S )Nr   )rK   rQ   rL   r   )r   r   r   r   rN   r   r   r   r      s    
z"Statement.rename_column_referencesc                 C   s   | j | j S r    rI   r   r   r   r   r      s    zStatement.__str__N)
r   r   r   r   r"   r	   r   r   r   r   r   r   r   r   rH      s   rH   c                       s8   e Zd Z fddZ fddZdd Zdd Z  ZS )	Expressionsc                    s@   || _ || _|| _dd | j j| jgD }t || d S )Nc                 S   s   g | ]}|j jqS r   )targetr   )r7   r2   r   r   r   
<listcomp>   s   z(Expressions.__init__.<locals>.<listcomp>)compilerexpressionsquote_valuequery	_gen_colsr+   r"   )r   r   rW   rV   rX   r&   r,   r   r   r"      s    zExpressions.__init__c                    s2   | j |krd S | j||i| _t || d S r    )r   rW   Zrelabeled_cloner+   r   r   r,   r   r   r      s    
z#Expressions.rename_table_referencesc                 C   sb   | j |krd S t| j}g | _| jj|gD ](}|jj|krF||j_| j	|jj q.|| _d S r    )
r   r   rW   r&   rV   rY   rZ   rT   r   append)r   r   r   r   rW   r2   r   r   r   r      s    

z$Expressions.rename_column_referencesc                 C   s*   | j | j\}}t| j|}|t| S r    )rV   compilerW   maprX   tuple)r   Zsqlparamsr   r   r   r      s    zExpressions.__str__)r   r   r   r"   r   r   r   r>   r   r   r,   r   rS      s   
rS   N)r   copyr   r   r   r$   r)   r?   rA   rC   rH   rS   r   r   r   r   <module>   s   $.'