module HDBCBug (main) where

import Test.Hspec

import Control.Exception

import Database.HDBC
import Database.HDBC.Sqlite3
import Data.List

-----------

-- The constraint tested in this file is derived from the table:
--
-- CREATE TABLE Confirmations (
--   oidh          INTEGER NOT NULL, -- (oidh,oidl) is key: only one confirmation per orderID
--   oidl          INTEGER NOT NULL,
--   timestamp             INTEGER NOT NULL,
--   ImmediateVolume       INTEGER,
--   ImmediateOrderStatus  INTEGER,
--
--   PRIMARY KEY (oidh, oidl)  -- table constraint
-- );


main :: IO ()
main = hspec $ do
        describe "DB Enforced Constraints" $ do

            describe "Confirmations table" $ do

                context "(oidh,oidl) is a key:" $do
                    it "1. We can insert two distinct rows" $ withDatabaseConnection $ \db -> do
                        clearTable db "Confirmations"
                        insertInDB db "Confirmations" $
                            [   toSql (5 :: Int),
                                toSql (6 :: Int),
                                toSql (7 :: Int),
                                SqlNull,
                                SqlNull
                            ]
                        commit db
                        insertInDB db "Confirmations" $
                            [   toSql (8 :: Int),
                                toSql (9 :: Int),
                                toSql (10:: Int),
                                SqlNull,
                                SqlNull
                            ]
                        commit db

                    it "2. but the table does not allow duplication of (oidh,oidl) pairs" $

                        --withDatabaseConnection $ \db -> do
                      do
                        db <- connectSqlite3 "mercado-data.db"

                        clearTable db "Confirmations"
                        insertInDB db "Confirmations" $
                            [   toSql (5 :: Int),
                                toSql (6 :: Int),
                                toSql (7 :: Int),
                                SqlNull,
                                SqlNull
                            ]
                        commit db
                        catch ( do
                            insertInDB db "Confirmations"
                                [   toSql (5 :: Int),
                                    toSql (6 :: Int),
                                    toSql (10:: Int),
                                    SqlNull,
                                    SqlNull
                                ]

                            putStrLn "We never get here."
                            commit db

                            ) ((\e -> do
                                    putStrLn "in handler"
                                    print e
                                    rollback db
                                    putStrLn "exception should be considered handled" ):: SomeException -> IO ())

                        -- disconnect db
                        catch (disconnect db)
                              ((\e -> do {putStrLn "thrown again"; print e; putStrLn "why!?"} ):: SomeException -> IO ())
                        putStrLn "---end---"

-------------
insertInDB :: Connection -> String -> [SqlValue] -> IO Integer
insertInDB db tableName vals = run db ("INSERT INTO " ++ tableName ++ " VALUES (" ++ qms ++ ")") vals
                where
                    qms = intersperse ',' $ replicate (length vals) '?' --question marks

-- Just for testing
insertInDB' :: Connection -> String -> [SqlValue] -> IO Integer
insertInDB' db tableName vals = throwSqlError (SqlError{ seState = "someState" , seNativeError = 9999, seErrorMsg = "some error msg"} )
                where
                    qms = intersperse ',' $ replicate (length vals) '?' --question marks

-----------
clearTable :: Connection -> String -> IO Integer
clearTable db tableName = run db ("DELETE FROM " ++ tableName ) []

----------
openConnection :: IO Connection
openConnection = connectSqlite3 "mercado-data.db"

closeConnection :: Connection -> IO ()
closeConnection = disconnect

withDatabaseConnection :: (Connection -> IO ()) -> IO ()
withDatabaseConnection action = bracket openConnection closeConnection action