import sqlite3
import typing

from hydrus.core import HydrusData
from hydrus.core import HydrusDBBase
from hydrus.core import HydrusExceptions
from hydrus.core import HydrusGlobals as HG
from hydrus.core import HydrusTags

from hydrus.client.db import ClientDBFilesStorage
from hydrus.client.db import ClientDBMaster
from hydrus.client.db import ClientDBModule
from hydrus.client.db import ClientDBServices

class ClientDBCacheLocalHashes( ClientDBModule.ClientDBModule ):
    
    def __init__( self, cursor: sqlite3.Cursor, modules_hashes: ClientDBMaster.ClientDBMasterHashes, modules_services: ClientDBServices.ClientDBMasterServices, modules_files_storage: ClientDBFilesStorage.ClientDBFilesStorage ):
        
        self.modules_hashes = modules_hashes
        self.modules_services = modules_services
        self.modules_files_storage = modules_files_storage
        
        self._hash_ids_to_hashes_cache = {}
        
        ClientDBModule.ClientDBModule.__init__( self, 'client hashes local cache', cursor )
        
    
    def _GetInitialTableGenerationDict( self ) -> dict:
        
        return {
            'external_caches.local_hashes_cache' : ( 'CREATE TABLE IF NOT EXISTS {} ( hash_id INTEGER PRIMARY KEY, hash BLOB_BYTES UNIQUE );', 429 )
        }
        
    
    def _PopulateHashIdsToHashesCache( self, hash_ids ):
        
        if len( self._hash_ids_to_hashes_cache ) > 100000:
            
            if not isinstance( hash_ids, set ):
                
                hash_ids = set( hash_ids )
                
            
            self._hash_ids_to_hashes_cache = { hash_id : hash for ( hash_id, hash ) in self._hash_ids_to_hashes_cache.items() if hash_id in hash_ids }
            
        
        uncached_hash_ids = { hash_id for hash_id in hash_ids if hash_id not in self._hash_ids_to_hashes_cache }
        
        if len( uncached_hash_ids ) > 0:
            
            if len( uncached_hash_ids ) == 1:
                
                ( uncached_hash_id, ) = uncached_hash_ids
                
                # this makes 0 or 1 rows, so do fetchall rather than fetchone
                local_uncached_hash_ids_to_hashes = { hash_id : hash for ( hash_id, hash ) in self._Execute( 'SELECT hash_id, hash FROM local_hashes_cache WHERE hash_id = ?;', ( uncached_hash_id, ) ) }
                
            else:
                
                with self._MakeTemporaryIntegerTable( uncached_hash_ids, 'hash_id' ) as temp_table_name:
                    
                    # temp hash_ids to actual hashes
                    local_uncached_hash_ids_to_hashes = { hash_id : hash for ( hash_id, hash ) in self._Execute( 'SELECT hash_id, hash FROM {} CROSS JOIN local_hashes_cache USING ( hash_id );'.format( temp_table_name ) ) }
                    
                
            
            self._hash_ids_to_hashes_cache.update( local_uncached_hash_ids_to_hashes )
            
            uncached_hash_ids = { hash_id for hash_id in uncached_hash_ids if hash_id not in self._hash_ids_to_hashes_cache }
            
        
        if len( uncached_hash_ids ) > 0:
            
            hash_ids_to_hashes = self.modules_hashes.GetHashIdsToHashes( hash_ids = uncached_hash_ids )
            
            self._hash_ids_to_hashes_cache.update( hash_ids_to_hashes )
            
        
    
    def _RepairRepopulateTables( self, table_names, cursor_transaction_wrapper: HydrusDBBase.DBCursorTransactionWrapper ):
        
        self.Repopulate()
        
    
    def AddHashIdsToCache( self, hash_ids ):
        
        hash_ids_to_hashes = self.modules_hashes.GetHashIdsToHashes( hash_ids = hash_ids )
        
        self._ExecuteMany( 'INSERT OR IGNORE INTO local_hashes_cache ( hash_id, hash ) VALUES ( ?, ? );', ( ( hash_id, sqlite3.Binary( hash ) ) for ( hash_id, hash ) in hash_ids_to_hashes.items() ) )
        
    
    def ClearCache( self ):
        
        self._Execute( 'DELETE FROM local_hashes_cache;' )
        
    
    def DropHashIdsFromCache( self, hash_ids ):
        
        self._ExecuteMany( 'DELETE FROM local_hashes_cache WHERE hash_id = ?;', ( ( hash_id, ) for hash_id in hash_ids ) )
        
    
    def GetHash( self, hash_id ) -> str:
        
        self._PopulateHashIdsToHashesCache( ( hash_id, ) )
        
        return self._hash_ids_to_hashes_cache[ hash_id ]
        
    
    def GetHashes( self, hash_ids ) -> typing.List[ bytes ]:
        
        self._PopulateHashIdsToHashesCache( hash_ids )
        
        return [ self._hash_ids_to_hashes_cache[ hash_id ] for hash_id in hash_ids ]
        
    
    def GetHashId( self, hash ) -> int:
        
        result = self._Execute( 'SELECT hash_id FROM local_hashes_cache WHERE hash = ?;', ( sqlite3.Binary( hash ), ) ).fetchone()
        
        if result is None:
            
            return self.modules_hashes.GetHashId( hash )
            
        else:
            
            ( hash_id, ) = result
            
        
        return hash_id
        
    
    def GetHashIds( self, hashes ) -> typing.Set[ int ]:
        
        hash_ids = set()
        hashes_not_in_cache = set()
        
        for hash in hashes:
            
            if hash is None:
                
                continue
                
            
            result = self._Execute( 'SELECT hash_id FROM local_hashes_cache WHERE hash = ?;', ( sqlite3.Binary( hash ), ) ).fetchone()
            
            if result is None:
                
                hashes_not_in_cache.add( hash )
                
            else:
                
                ( hash_id, ) = result
                
                hash_ids.add( hash_id )
                
            
        
        if len( hashes_not_in_cache ) > 0:
            
            hash_ids.update( self.modules_hashes.GetHashIds( hashes_not_in_cache ) )
            
        
        return hash_ids
        
    
    def GetHashIdsToHashes( self, hash_ids = None, hashes = None ) -> typing.Dict[ int, str ]:
        
        if hash_ids is not None:
            
            self._PopulateHashIdsToHashesCache( hash_ids )
            
            hash_ids_to_hashes = { hash_id : self._hash_ids_to_hashes_cache[ hash_id ] for hash_id in hash_ids }
            
        elif hashes is not None:
            
            hash_ids_to_hashes = { self.GetHashId( hash ) : hash for hash in hashes }
            
        
        return hash_ids_to_hashes
        
    
    def GetTablesAndColumnsThatUseDefinitions( self, content_type: int ) -> typing.List[ typing.Tuple[ str, str ] ]:
        
        # we actually provide a backup, which we may want to automate later in mappings caches etc...
        
        return []
        
    
    def HasHashId( self, hash_id: int ):
        
        result = self._Execute( 'SELECT 1 FROM local_hashes_cache WHERE hash_id = ?;', ( hash_id, ) ).fetchone()
        
        return result is not None
        
    
    def Repopulate( self ):
        
        self.ClearCache()
        
        HG.client_controller.frame_splash_status.SetSubtext( 'reading local file data' )
        
        local_hash_ids = self.modules_files_storage.GetCurrentHashIdsList( self.modules_services.combined_local_file_service_id )
        
        BLOCK_SIZE = 10000
        num_to_do = len( local_hash_ids )
        
        for ( i, block_of_hash_ids ) in enumerate( HydrusData.SplitListIntoChunks( local_hash_ids, BLOCK_SIZE ) ):
            
            HG.client_controller.frame_splash_status.SetSubtext( 'caching local file data {}'.format( HydrusData.ConvertValueRangeToPrettyString( i * BLOCK_SIZE, num_to_do ) ) )
            
            self.AddHashIdsToCache( block_of_hash_ids )
            
        
    
class ClientDBCacheLocalTags( ClientDBModule.ClientDBModule ):
    
    def __init__( self, cursor: sqlite3.Cursor, modules_tags: ClientDBMaster.ClientDBMasterTags ):
        
        self.modules_tags = modules_tags
        
        self._tag_ids_to_tags_cache = {}
        
        ClientDBModule.ClientDBModule.__init__( self, 'client tags local cache', cursor )
        
    
    def _GetInitialTableGenerationDict( self ) -> dict:
        
        return {
            'external_caches.local_tags_cache' : ( 'CREATE TABLE IF NOT EXISTS {} ( tag_id INTEGER PRIMARY KEY, tag TEXT UNIQUE );', 400 )
        }
        
    
    def _PopulateTagIdsToTagsCache( self, tag_ids ):
        
        if len( self._tag_ids_to_tags_cache ) > 100000:
            
            if not isinstance( tag_ids, set ):
                
                tag_ids = set( tag_ids )
                
            
            self._tag_ids_to_tags_cache = { tag_id : tag for ( tag_id, tag ) in self._tag_ids_to_tags_cache.items() if tag_id in tag_ids }
            
        
        uncached_tag_ids = { tag_id for tag_id in tag_ids if tag_id not in self._tag_ids_to_tags_cache }
        
        if len( uncached_tag_ids ) > 0:
            
            if len( uncached_tag_ids ) == 1:
                
                ( uncached_tag_id, ) = uncached_tag_ids
                
                # this makes 0 or 1 rows, so do fetchall rather than fetchone
                local_uncached_tag_ids_to_tags = { tag_id : tag for ( tag_id, tag ) in self._Execute( 'SELECT tag_id, tag FROM local_tags_cache WHERE tag_id = ?;', ( uncached_tag_id, ) ) }
                
            else:
                
                with self._MakeTemporaryIntegerTable( uncached_tag_ids, 'tag_id' ) as temp_table_name:
                    
                    # temp tag_ids to actual tags
                    local_uncached_tag_ids_to_tags = { tag_id : tag for ( tag_id, tag ) in self._Execute( 'SELECT tag_id, tag FROM {} CROSS JOIN local_tags_cache USING ( tag_id );'.format( temp_table_name ) ) }
                    
                
            
            self._tag_ids_to_tags_cache.update( local_uncached_tag_ids_to_tags )
            
            uncached_tag_ids = { tag_id for tag_id in uncached_tag_ids if tag_id not in self._tag_ids_to_tags_cache }
            
        
        if len( uncached_tag_ids ) > 0:
            
            tag_ids_to_tags = self.modules_tags.GetTagIdsToTags( tag_ids = uncached_tag_ids )
            
            self._tag_ids_to_tags_cache.update( tag_ids_to_tags )
            
        
    
    def _RepairRepopulateTables( self, table_names, cursor_transaction_wrapper: HydrusDBBase.DBCursorTransactionWrapper ):
        
        message = 'Unfortunately, the local tag cache cannot repopulate itself yet during repair. Once you boot, please run _database->regenerate->local tag cache_. This message has been printed to the log.'
        
        HydrusData.DebugPrint( message )
        
        ClientDBModule.BlockingSafeShowMessage( message )
        
    
    def AddTagIdsToCache( self, tag_ids ):
        
        tag_ids_to_tags = self.modules_tags.GetTagIdsToTags( tag_ids = tag_ids )
        
        self._ExecuteMany( 'INSERT OR IGNORE INTO local_tags_cache ( tag_id, tag ) VALUES ( ?, ? );', tag_ids_to_tags.items() )
        
    
    def ClearCache( self ):
        
        self._Execute( 'DELETE FROM local_tags_cache;' )
        
    
    def DropTagIdsFromCache( self, tag_ids ):
        
        self._ExecuteMany( 'DELETE FROM local_tags_cache WHERE tag_id = ?;', ( ( tag_id, ) for tag_id in tag_ids ) )
        
    
    def GetTablesAndColumnsThatUseDefinitions( self, content_type: int ) -> typing.List[ typing.Tuple[ str, str ] ]:
        
        # we actually provide a backup, which we may want to automate later in mappings caches etc...
        
        return []
        
    
    def GetTag( self, tag_id ) -> str:
        
        self._PopulateTagIdsToTagsCache( ( tag_id, ) )
        
        return self._tag_ids_to_tags_cache[ tag_id ]
        
    
    def GetTagId( self, tag ) -> int:
        
        clean_tag = HydrusTags.CleanTag( tag )
        
        try:
            
            HydrusTags.CheckTagNotEmpty( clean_tag )
            
        except HydrusExceptions.TagSizeException:
            
            raise HydrusExceptions.TagSizeException( '"{}" tag seems not valid--when cleaned, it ends up with zero size!'.format( tag ) )
            
        
        result = self._Execute( 'SELECT tag_id FROM local_tags_cache WHERE tag = ?;', ( tag, ) ).fetchone()
        
        if result is None:
            
            return self.modules_tags.GetTagId( tag )
            
        else:
            
            ( tag_id, ) = result
            
        
        return tag_id
        
    
    def GetTagIdsToTags( self, tag_ids = None, tags = None ) -> typing.Dict[ int, str ]:
        
        if tag_ids is not None:
            
            self._PopulateTagIdsToTagsCache( tag_ids )
            
            tag_ids_to_tags = { tag_id : self._tag_ids_to_tags_cache[ tag_id ] for tag_id in tag_ids }
            
        elif tags is not None:
            
            tag_ids_to_tags = { self.GetTagId( tag ) : tag for tag in tags }
            
        
        return tag_ids_to_tags
        
    
    def UpdateTagInCache( self, tag_id, tag ):
        
        self._Execute( 'UPDATE local_tags_cache SET tag = ? WHERE tag_id = ?;', ( tag, tag_id ) )
        
        if tag_id in self._tag_ids_to_tags_cache:
            
            del self._tag_ids_to_tags_cache[ tag_id ]
            
        
    
