Base.hs

module TutorialD.Interpreter.Import.Base where
import ProjectM36.Base
import ProjectM36.Error
import Data.Monoid

-- | import data into a relation variable
data RelVarDataImportOperator = RelVarDataImportOperator RelVarName FilePath (RelVarName -> Attributes -> FilePath -> IO (Either RelationalError DatabaseContextExpr))

instance Show RelVarDataImportOperator where
  show (RelVarDataImportOperator rv path _) = "RelVarDataImportOperator " <> show rv <> " " <> path

-- | import data into a database context
data DatabaseContextDataImportOperator = DatabaseContextDataImportOperator FilePath (FilePath -> IO (Either RelationalError DatabaseContextExpr))

instance Show DatabaseContextDataImportOperator where
  show (DatabaseContextDataImportOperator path _) = "DatabaseContextDataImportOperator " <> path

-- perhaps create a structure to import a whole transaction graph section in the future

evalRelVarDataImportOperator :: RelVarDataImportOperator -> Attributes -> IO (Either RelationalError DatabaseContextExpr)
evalRelVarDataImportOperator (RelVarDataImportOperator relVarName path importFunc) attrs = importFunc relVarName attrs path 
        
evalDatabaseContextDataImportOperator :: DatabaseContextDataImportOperator -> IO (Either RelationalError DatabaseContextExpr)        
evalDatabaseContextDataImportOperator (DatabaseContextDataImportOperator path importFunc) = importFunc path