{-# LANGUAGE DataKinds #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE FunctionalDependencies #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TypeApplications #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE TypeOperators #-}
{-# LANGUAGE UndecidableInstances #-}

{-# OPTIONS_GHC -fno-warn-orphans #-}

module Database.Esqueleto.Experimental.From.Join
    ( (:&)(..)
    , ValidOnClause
    , on
    , ErrorOnLateral
    , fromJoin
    , HasOnClause
    , innerJoin
    , innerJoinLateral
    , crossJoin
    , crossJoinLateral
    , leftJoin
    , leftJoinLateral
    , rightJoin
    , fullOuterJoin
    , GetFirstTable(..)
    , getTable
    , getTableMaybe
    -- Compatability for old syntax
    , Lateral
    , NotLateral
    , IsLateral
    , DoInnerJoin(..)
    , DoLeftJoin(..)
    , DoCrossJoin(..)
    ) where

import Data.Bifunctor (first)
import Data.Kind (Constraint)
import Data.Proxy
import qualified Data.Text.Lazy.Builder as TLB
import Database.Esqueleto.Experimental.From
import Database.Esqueleto.Experimental.ToAlias
import Database.Esqueleto.Experimental.ToAliasReference
import Database.Esqueleto.Experimental.ToMaybe
import Database.Esqueleto.Internal.Internal hiding
       (From(..), from, fromJoin, on)
import Database.Esqueleto.Internal.PersistentImport (Entity)
import GHC.TypeLits

instance (ToMaybe a, ToMaybe b) => ToMaybe (a :& b) where
    type ToMaybeT (a :& b) = (ToMaybeT a :& ToMaybeT b)
    toMaybe :: (a :& b) -> ToMaybeT (a :& b)
toMaybe (a
a :& b
b) = (forall a. ToMaybe a => a -> ToMaybeT a
toMaybe a
a forall a b. a -> b -> a :& b
:& forall a. ToMaybe a => a -> ToMaybeT a
toMaybe b
b)

class ValidOnClause a
instance {-# OVERLAPPABLE #-} ToFrom a a' => ValidOnClause a
instance ValidOnClause (a -> SqlQuery b)

-- | You may return joined values from a 'select' query - this is
-- identical to the tuple instance, but is provided for convenience.
--
-- @since 3.5.2.0
instance (SqlSelect a ra, SqlSelect b rb) => SqlSelect (a :& b) (ra :& rb) where
    sqlSelectCols :: IdentInfo -> (a :& b) -> (Builder, [PersistValue])
sqlSelectCols IdentInfo
esc (a
a :& b
b) = forall a r.
SqlSelect a r =>
IdentInfo -> a -> (Builder, [PersistValue])
sqlSelectCols IdentInfo
esc (a
a, b
b)
    sqlSelectColCount :: Proxy (a :& b) -> Int
sqlSelectColCount = forall a r. SqlSelect a r => Proxy a -> Int
sqlSelectColCount forall b c a. (b -> c) -> (a -> b) -> a -> c
. Proxy (a :& b) -> Proxy (a, b)
toTuple
      where
        toTuple :: Proxy (a :& b) -> Proxy (a, b)
        toTuple :: Proxy (a :& b) -> Proxy (a, b)
toTuple = forall a b. a -> b -> a
const forall {k} (t :: k). Proxy t
Proxy
    sqlSelectProcessRow :: [PersistValue] -> Either Text (ra :& rb)
sqlSelectProcessRow = forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap (forall a b c. (a -> b -> c) -> (a, b) -> c
uncurry forall a b. a -> b -> a :& b
(:&)) forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a r. SqlSelect a r => [PersistValue] -> Either Text r
sqlSelectProcessRow

-- | Identical to the tuple instance and provided for convenience.
--
-- @since 3.5.3.0
instance (ToAlias a, ToAlias b) => ToAlias (a :& b) where
    toAlias :: (a :& b) -> SqlQuery (a :& b)
toAlias (a
a :& b
b) = forall a b. a -> b -> a :& b
(:&) forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> forall a. ToAlias a => a -> SqlQuery a
toAlias a
a forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> forall a. ToAlias a => a -> SqlQuery a
toAlias b
b

-- | Identical to the tuple instance and provided for convenience.
--
-- @since 3.5.3.0
instance (ToAliasReference a, ToAliasReference b) => ToAliasReference (a :& b) where
    toAliasReference :: Ident -> (a :& b) -> SqlQuery (a :& b)
toAliasReference Ident
ident (a
a :& b
b) = forall a b. a -> b -> a :& b
(:&) forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> (forall a. ToAliasReference a => Ident -> a -> SqlQuery a
toAliasReference Ident
ident a
a) forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> (forall a. ToAliasReference a => Ident -> a -> SqlQuery a
toAliasReference Ident
ident b
b)

-- | An @ON@ clause that describes how two tables are related. This should be
-- used as an infix operator after a 'JOIN'. For example,
--
-- @
-- select $
-- from $ table \@Person
-- \`innerJoin\` table \@BlogPost
-- \`on\` (\\(p :& bP) ->
--         p ^. PersonId ==. bP ^. BlogPostAuthorId)
-- @
on :: ValidOnClause a => a -> (b -> SqlExpr (Value Bool)) -> (a, b -> SqlExpr (Value Bool))
on :: forall a b.
ValidOnClause a =>
a -> (b -> SqlExpr (Value Bool)) -> (a, b -> SqlExpr (Value Bool))
on = (,)
infix 9 `on`

type family ErrorOnLateral a :: Constraint where
  ErrorOnLateral (a -> SqlQuery b) = TypeError ('Text "LATERAL can only be used for INNER, LEFT, and CROSS join kinds.")
  ErrorOnLateral _ = ()

fromJoin :: TLB.Builder -> RawFn -> RawFn -> Maybe (SqlExpr (Value Bool)) -> RawFn
fromJoin :: Builder -> RawFn -> RawFn -> Maybe (SqlExpr (Value Bool)) -> RawFn
fromJoin Builder
joinKind RawFn
lhs RawFn
rhs Maybe (SqlExpr (Value Bool))
monClause =
    \NeedParens
paren IdentInfo
info ->
        forall (p :: * -> * -> *) a b c.
Bifunctor p =>
(a -> b) -> p a c -> p b c
first (NeedParens -> Builder -> Builder
parensM NeedParens
paren) forall a b. (a -> b) -> a -> b
$
        forall a. Monoid a => [a] -> a
mconcat [ RawFn
lhs NeedParens
Never IdentInfo
info
                , (Builder
joinKind, forall a. Monoid a => a
mempty)
                , RawFn
rhs NeedParens
Parens IdentInfo
info
                , forall b a. b -> (a -> b) -> Maybe a -> b
maybe forall a. Monoid a => a
mempty (forall {a}. IdentInfo -> SqlExpr a -> (Builder, [PersistValue])
makeOnClause IdentInfo
info) Maybe (SqlExpr (Value Bool))
monClause
                ]
    where
        makeOnClause :: IdentInfo -> SqlExpr a -> (Builder, [PersistValue])
makeOnClause IdentInfo
info (ERaw SqlExprMeta
_ RawFn
f)        = forall (p :: * -> * -> *) a b c.
Bifunctor p =>
(a -> b) -> p a c -> p b c
first (Builder
" ON " forall a. Semigroup a => a -> a -> a
<>) (RawFn
f NeedParens
Never IdentInfo
info)

type family HasOnClause actual expected :: Constraint where
    HasOnClause (a, b -> SqlExpr (Value Bool)) c = () -- Let the compiler handle the type mismatch
    HasOnClause a expected =
        TypeError ( 'Text "Missing ON clause for join with"
                    ':$$: 'ShowType a
                    ':$$: 'Text ""
                    ':$$: 'Text "Expected: "
                    ':$$: 'ShowType a
                    ':$$: 'Text "`on` " ':<>: 'ShowType (expected -> SqlExpr (Value Bool))
                    ':$$: 'Text ""
                  )


-- | INNER JOIN
--
-- Used as an infix operator \`innerJoin\`
--
-- @
-- select $
-- from $ table \@Person
-- \`innerJoin\` table \@BlogPost
-- \`on\` (\\(p :& bp) ->
--         p ^. PersonId ==. bp ^. BlogPostAuthorId)
-- @
--
-- @since 3.5.0.0
innerJoin :: ( ToFrom a a'
             , ToFrom b b'
             , HasOnClause rhs (a' :& b')
             , rhs ~ (b, (a' :& b') -> SqlExpr (Value Bool))
             ) => a -> rhs -> From (a' :& b')
innerJoin :: forall a a' b b' rhs.
(ToFrom a a', ToFrom b b', HasOnClause rhs (a' :& b'),
 rhs ~ (b, (a' :& b') -> SqlExpr (Value Bool))) =>
a -> rhs -> From (a' :& b')
innerJoin a
lhs (b
rhs, (a' :& b') -> SqlExpr (Value Bool)
on') = forall a. SqlQuery (a, RawFn) -> From a
From forall a b. (a -> b) -> a -> b
$ do
     (a'
leftVal, RawFn
leftFrom) <- forall a. From a -> SqlQuery (a, RawFn)
unFrom (forall a r. ToFrom a r => a -> From r
toFrom a
lhs)
     (b'
rightVal, RawFn
rightFrom) <- forall a. From a -> SqlQuery (a, RawFn)
unFrom (forall a r. ToFrom a r => a -> From r
toFrom b
rhs)
     let ret :: a' :& b'
ret = a'
leftVal forall a b. a -> b -> a :& b
:& b'
rightVal
     forall (f :: * -> *) a. Applicative f => a -> f a
pure forall a b. (a -> b) -> a -> b
$ (a' :& b'
ret, Builder -> RawFn -> RawFn -> Maybe (SqlExpr (Value Bool)) -> RawFn
fromJoin Builder
" INNER JOIN " RawFn
leftFrom RawFn
rightFrom (forall a. a -> Maybe a
Just forall a b. (a -> b) -> a -> b
$ (a' :& b') -> SqlExpr (Value Bool)
on' a' :& b'
ret))


-- | INNER JOIN LATERAL
--
-- A Lateral subquery join allows the joined query to reference entities from the
-- left hand side of the join. Discards rows that don't match the on clause
--
-- Used as an infix operator \`innerJoinLateral\`
--
-- See example 6
--
-- @since 3.5.0.0
innerJoinLateral :: ( ToFrom a a'
                    , HasOnClause rhs (a' :& b)
                    , SqlSelect b r
                    , ToAlias b
                    , ToAliasReference b
                    , rhs ~ (a' -> SqlQuery b, (a' :& b) -> SqlExpr (Value Bool))
                    )
                 => a -> rhs -> From (a' :& b)
innerJoinLateral :: forall a a' rhs b r.
(ToFrom a a', HasOnClause rhs (a' :& b), SqlSelect b r, ToAlias b,
 ToAliasReference b,
 rhs ~ (a' -> SqlQuery b, (a' :& b) -> SqlExpr (Value Bool))) =>
a -> rhs -> From (a' :& b)
innerJoinLateral a
lhs (a' -> SqlQuery b
rhsFn, (a' :& b) -> SqlExpr (Value Bool)
on') = forall a. SqlQuery (a, RawFn) -> From a
From forall a b. (a -> b) -> a -> b
$ do
     (a'
leftVal, RawFn
leftFrom) <- forall a. From a -> SqlQuery (a, RawFn)
unFrom (forall a r. ToFrom a r => a -> From r
toFrom a
lhs)
     (b
rightVal, RawFn
rightFrom) <- forall a. From a -> SqlQuery (a, RawFn)
unFrom (forall a r.
(SqlSelect a r, ToAlias a, ToAliasReference a) =>
SqlQuery a -> From a
selectQuery (a' -> SqlQuery b
rhsFn a'
leftVal))
     let ret :: a' :& b
ret = a'
leftVal forall a b. a -> b -> a :& b
:& b
rightVal
     forall (f :: * -> *) a. Applicative f => a -> f a
pure forall a b. (a -> b) -> a -> b
$ (a' :& b
ret, Builder -> RawFn -> RawFn -> Maybe (SqlExpr (Value Bool)) -> RawFn
fromJoin Builder
" INNER JOIN LATERAL " RawFn
leftFrom RawFn
rightFrom (forall a. a -> Maybe a
Just forall a b. (a -> b) -> a -> b
$ (a' :& b) -> SqlExpr (Value Bool)
on' a' :& b
ret))

-- | CROSS JOIN
--
-- Used as an infix \`crossJoin\`
--
-- @
-- select $ do
-- from $ table \@Person
-- \`crossJoin\` table \@BlogPost
-- @
--
-- @since 3.5.0.0
crossJoin :: ( ToFrom a a'
             , ToFrom b b'
             ) => a -> b -> From (a' :& b')
crossJoin :: forall a a' b b'.
(ToFrom a a', ToFrom b b') =>
a -> b -> From (a' :& b')
crossJoin a
lhs b
rhs = forall a. SqlQuery (a, RawFn) -> From a
From forall a b. (a -> b) -> a -> b
$ do
     (a'
leftVal, RawFn
leftFrom) <- forall a. From a -> SqlQuery (a, RawFn)
unFrom (forall a r. ToFrom a r => a -> From r
toFrom a
lhs)
     (b'
rightVal, RawFn
rightFrom) <- forall a. From a -> SqlQuery (a, RawFn)
unFrom (forall a r. ToFrom a r => a -> From r
toFrom b
rhs)
     let ret :: a' :& b'
ret = a'
leftVal forall a b. a -> b -> a :& b
:& b'
rightVal
     forall (f :: * -> *) a. Applicative f => a -> f a
pure forall a b. (a -> b) -> a -> b
$ (a' :& b'
ret, Builder -> RawFn -> RawFn -> Maybe (SqlExpr (Value Bool)) -> RawFn
fromJoin Builder
" CROSS JOIN " RawFn
leftFrom RawFn
rightFrom forall a. Maybe a
Nothing)

-- | CROSS JOIN LATERAL
--
-- A Lateral subquery join allows the joined query to reference entities from the
-- left hand side of the join.
--
-- Used as an infix operator \`crossJoinLateral\`
--
-- See example 6
--
-- @since 3.5.0.0
crossJoinLateral :: ( ToFrom a a'
                    , SqlSelect b r
                    , ToAlias b
                    , ToAliasReference b
                    )
                 => a -> (a' -> SqlQuery b) -> From (a' :& b)
crossJoinLateral :: forall a a' b r.
(ToFrom a a', SqlSelect b r, ToAlias b, ToAliasReference b) =>
a -> (a' -> SqlQuery b) -> From (a' :& b)
crossJoinLateral a
lhs a' -> SqlQuery b
rhsFn = forall a. SqlQuery (a, RawFn) -> From a
From forall a b. (a -> b) -> a -> b
$ do
     (a'
leftVal, RawFn
leftFrom) <- forall a. From a -> SqlQuery (a, RawFn)
unFrom (forall a r. ToFrom a r => a -> From r
toFrom a
lhs)
     (b
rightVal, RawFn
rightFrom) <- forall a. From a -> SqlQuery (a, RawFn)
unFrom (forall a r.
(SqlSelect a r, ToAlias a, ToAliasReference a) =>
SqlQuery a -> From a
selectQuery (a' -> SqlQuery b
rhsFn a'
leftVal))
     let ret :: a' :& b
ret = a'
leftVal forall a b. a -> b -> a :& b
:& b
rightVal
     forall (f :: * -> *) a. Applicative f => a -> f a
pure forall a b. (a -> b) -> a -> b
$ (a' :& b
ret, Builder -> RawFn -> RawFn -> Maybe (SqlExpr (Value Bool)) -> RawFn
fromJoin Builder
" CROSS JOIN LATERAL " RawFn
leftFrom RawFn
rightFrom forall a. Maybe a
Nothing)

-- | LEFT OUTER JOIN
--
-- Join where the right side may not exist.
-- If the on clause fails then the right side will be NULL'ed
-- Because of this the right side needs to be handled as a Maybe
--
-- Used as an infix operator \`leftJoin\`
--
-- @
-- select $
-- from $ table \@Person
-- \`leftJoin\` table \@BlogPost
-- \`on\` (\\(p :& bp) ->
--         just (p ^. PersonId) ==. bp ?. BlogPostAuthorId)
-- @
--
-- @since 3.5.0.0
leftJoin :: ( ToFrom a a'
            , ToFrom b b'
            , ToMaybe b'
            , HasOnClause rhs (a' :& ToMaybeT b')
            , rhs ~ (b, (a' :& ToMaybeT b') -> SqlExpr (Value Bool))
            ) => a -> rhs -> From (a' :& ToMaybeT b')
leftJoin :: forall a a' b b' rhs.
(ToFrom a a', ToFrom b b', ToMaybe b',
 HasOnClause rhs (a' :& ToMaybeT b'),
 rhs ~ (b, (a' :& ToMaybeT b') -> SqlExpr (Value Bool))) =>
a -> rhs -> From (a' :& ToMaybeT b')
leftJoin a
lhs (b
rhs, (a' :& ToMaybeT b') -> SqlExpr (Value Bool)
on') = forall a. SqlQuery (a, RawFn) -> From a
From forall a b. (a -> b) -> a -> b
$ do
     (a'
leftVal, RawFn
leftFrom) <- forall a. From a -> SqlQuery (a, RawFn)
unFrom (forall a r. ToFrom a r => a -> From r
toFrom a
lhs)
     (b'
rightVal, RawFn
rightFrom) <- forall a. From a -> SqlQuery (a, RawFn)
unFrom (forall a r. ToFrom a r => a -> From r
toFrom b
rhs)
     let ret :: a' :& ToMaybeT b'
ret = a'
leftVal forall a b. a -> b -> a :& b
:& forall a. ToMaybe a => a -> ToMaybeT a
toMaybe b'
rightVal
     forall (f :: * -> *) a. Applicative f => a -> f a
pure forall a b. (a -> b) -> a -> b
$ (a' :& ToMaybeT b'
ret, Builder -> RawFn -> RawFn -> Maybe (SqlExpr (Value Bool)) -> RawFn
fromJoin Builder
" LEFT OUTER JOIN " RawFn
leftFrom RawFn
rightFrom (forall a. a -> Maybe a
Just forall a b. (a -> b) -> a -> b
$ (a' :& ToMaybeT b') -> SqlExpr (Value Bool)
on' a' :& ToMaybeT b'
ret))

-- | LEFT OUTER JOIN LATERAL
--
-- Lateral join where the right side may not exist.
-- In the case that the query returns nothing or the on clause fails the right
-- side of the join will be NULL'ed
-- Because of this the right side needs to be handled as a Maybe
--
-- Used as an infix operator \`leftJoinLateral\`
--
-- See example 6 for how to use LATERAL
--
-- @since 3.5.0.0
leftJoinLateral :: ( ToFrom a a'
                   , SqlSelect b r
                   , HasOnClause rhs (a' :& ToMaybeT b)
                   , ToAlias b
                   , ToAliasReference b
                   , ToMaybe b
                   , rhs ~ (a' -> SqlQuery b, (a' :& ToMaybeT b) -> SqlExpr (Value Bool))
                   )
                 => a -> rhs -> From (a' :& ToMaybeT b)
leftJoinLateral :: forall a a' b r rhs.
(ToFrom a a', SqlSelect b r, HasOnClause rhs (a' :& ToMaybeT b),
 ToAlias b, ToAliasReference b, ToMaybe b,
 rhs
 ~ (a' -> SqlQuery b,
    (a' :& ToMaybeT b) -> SqlExpr (Value Bool))) =>
a -> rhs -> From (a' :& ToMaybeT b)
leftJoinLateral a
lhs (a' -> SqlQuery b
rhsFn, (a' :& ToMaybeT b) -> SqlExpr (Value Bool)
on') = forall a. SqlQuery (a, RawFn) -> From a
From forall a b. (a -> b) -> a -> b
$ do
     (a'
leftVal, RawFn
leftFrom) <- forall a. From a -> SqlQuery (a, RawFn)
unFrom (forall a r. ToFrom a r => a -> From r
toFrom a
lhs)
     (b
rightVal, RawFn
rightFrom) <- forall a. From a -> SqlQuery (a, RawFn)
unFrom (forall a r.
(SqlSelect a r, ToAlias a, ToAliasReference a) =>
SqlQuery a -> From a
selectQuery (a' -> SqlQuery b
rhsFn a'
leftVal))
     let ret :: a' :& ToMaybeT b
ret = a'
leftVal forall a b. a -> b -> a :& b
:& forall a. ToMaybe a => a -> ToMaybeT a
toMaybe b
rightVal
     forall (f :: * -> *) a. Applicative f => a -> f a
pure forall a b. (a -> b) -> a -> b
$ (a' :& ToMaybeT b
ret, Builder -> RawFn -> RawFn -> Maybe (SqlExpr (Value Bool)) -> RawFn
fromJoin Builder
" LEFT OUTER JOIN LATERAL " RawFn
leftFrom RawFn
rightFrom (forall a. a -> Maybe a
Just forall a b. (a -> b) -> a -> b
$ (a' :& ToMaybeT b) -> SqlExpr (Value Bool)
on' a' :& ToMaybeT b
ret))

-- | RIGHT OUTER JOIN
--
-- Join where the left side may not exist.
-- If the on clause fails then the left side will be NULL'ed
-- Because of this the left side needs to be handled as a Maybe
--
-- Used as an infix operator \`rightJoin\`
--
-- @
-- select $
-- from $ table \@Person
-- \`rightJoin\` table \@BlogPost
-- \`on\` (\\(p :& bp) ->
--         p ?. PersonId ==. bp ^. BlogPostAuthorId)
-- @
--
-- @since 3.5.0.0
rightJoin :: ( ToFrom a a'
             , ToFrom b b'
             , ToMaybe a'
             , HasOnClause rhs (ToMaybeT a' :& b')
             , rhs ~ (b, (ToMaybeT a' :& b') -> SqlExpr (Value Bool))
             ) => a -> rhs -> From (ToMaybeT a' :& b')
rightJoin :: forall a a' b b' rhs.
(ToFrom a a', ToFrom b b', ToMaybe a',
 HasOnClause rhs (ToMaybeT a' :& b'),
 rhs ~ (b, (ToMaybeT a' :& b') -> SqlExpr (Value Bool))) =>
a -> rhs -> From (ToMaybeT a' :& b')
rightJoin a
lhs (b
rhs, (ToMaybeT a' :& b') -> SqlExpr (Value Bool)
on') = forall a. SqlQuery (a, RawFn) -> From a
From forall a b. (a -> b) -> a -> b
$ do
     (a'
leftVal, RawFn
leftFrom) <- forall a. From a -> SqlQuery (a, RawFn)
unFrom (forall a r. ToFrom a r => a -> From r
toFrom a
lhs)
     (b'
rightVal, RawFn
rightFrom) <- forall a. From a -> SqlQuery (a, RawFn)
unFrom (forall a r. ToFrom a r => a -> From r
toFrom b
rhs)
     let ret :: ToMaybeT a' :& b'
ret = forall a. ToMaybe a => a -> ToMaybeT a
toMaybe a'
leftVal forall a b. a -> b -> a :& b
:& b'
rightVal
     forall (f :: * -> *) a. Applicative f => a -> f a
pure forall a b. (a -> b) -> a -> b
$ (ToMaybeT a' :& b'
ret, Builder -> RawFn -> RawFn -> Maybe (SqlExpr (Value Bool)) -> RawFn
fromJoin Builder
" RIGHT OUTER JOIN " RawFn
leftFrom RawFn
rightFrom (forall a. a -> Maybe a
Just forall a b. (a -> b) -> a -> b
$ (ToMaybeT a' :& b') -> SqlExpr (Value Bool)
on' ToMaybeT a' :& b'
ret))

-- | FULL OUTER JOIN
--
-- Join where both sides of the join may not exist.
-- Because of this the result needs to be handled as a Maybe
--
-- Used as an infix operator \`fullOuterJoin\`
--
-- @
-- select $
-- from $ table \@Person
-- \`fullOuterJoin\` table \@BlogPost
-- \`on\` (\\(p :& bp) ->
--         p ?. PersonId ==. bp ?. BlogPostAuthorId)
-- @
--
-- @since 3.5.0.0
fullOuterJoin :: ( ToFrom a a'
                 , ToFrom b b'
                 , ToMaybe a'
                 , ToMaybe b'
                 , HasOnClause rhs (ToMaybeT a' :& ToMaybeT b')
                 , rhs ~ (b, (ToMaybeT a' :& ToMaybeT b') -> SqlExpr (Value Bool))
                 ) => a -> rhs -> From (ToMaybeT a' :& ToMaybeT b')
fullOuterJoin :: forall a a' b b' rhs.
(ToFrom a a', ToFrom b b', ToMaybe a', ToMaybe b',
 HasOnClause rhs (ToMaybeT a' :& ToMaybeT b'),
 rhs ~ (b, (ToMaybeT a' :& ToMaybeT b') -> SqlExpr (Value Bool))) =>
a -> rhs -> From (ToMaybeT a' :& ToMaybeT b')
fullOuterJoin a
lhs (b
rhs, (ToMaybeT a' :& ToMaybeT b') -> SqlExpr (Value Bool)
on') = forall a. SqlQuery (a, RawFn) -> From a
From forall a b. (a -> b) -> a -> b
$ do
     (a'
leftVal, RawFn
leftFrom) <- forall a. From a -> SqlQuery (a, RawFn)
unFrom (forall a r. ToFrom a r => a -> From r
toFrom a
lhs)
     (b'
rightVal, RawFn
rightFrom) <- forall a. From a -> SqlQuery (a, RawFn)
unFrom (forall a r. ToFrom a r => a -> From r
toFrom b
rhs)
     let ret :: ToMaybeT a' :& ToMaybeT b'
ret = forall a. ToMaybe a => a -> ToMaybeT a
toMaybe a'
leftVal forall a b. a -> b -> a :& b
:& forall a. ToMaybe a => a -> ToMaybeT a
toMaybe b'
rightVal
     forall (f :: * -> *) a. Applicative f => a -> f a
pure forall a b. (a -> b) -> a -> b
$ (ToMaybeT a' :& ToMaybeT b'
ret, Builder -> RawFn -> RawFn -> Maybe (SqlExpr (Value Bool)) -> RawFn
fromJoin Builder
" FULL OUTER JOIN " RawFn
leftFrom RawFn
rightFrom (forall a. a -> Maybe a
Just forall a b. (a -> b) -> a -> b
$ (ToMaybeT a' :& ToMaybeT b') -> SqlExpr (Value Bool)
on' ToMaybeT a' :& ToMaybeT b'
ret))

infixl 2 `innerJoin`,
         `innerJoinLateral`,
         `leftJoin`,
         `leftJoinLateral`,
         `crossJoin`,
         `crossJoinLateral`,
         `rightJoin`,
         `fullOuterJoin`

-- | Typeclass for selecting tables using type application syntax.
--
-- If you have a long chain of tables joined with `(:&)`, like
-- @a :& b :& c :& d@, then @getTable \@c (a :& b :& c :& d)@ will give you the
-- @c@ table back.
--
-- Note that this typeclass will only select the first table of the given type;
-- it may be less useful if there's multiple tables of the same type.
--
-- @since 3.5.9.0
class GetFirstTable t ts where
  -- | Get the first table of type `t` from the tables `ts`.
  --
  -- @since 3.5.9.0
  getFirstTable :: ts -> t

instance GetFirstTable t (t :& ts) where
  getFirstTable :: (t :& ts) -> t
getFirstTable (t
t :& ts
_) = t
t

instance GetFirstTable t (x :& t) where
  getFirstTable :: (x :& t) -> t
getFirstTable (x
_ :& t
t) = t
t

-- The associativity of (:&) means we do the recursion along the left-hand side.
instance {-# OVERLAPPABLE #-} GetFirstTable t ts => GetFirstTable t (ts :& x) where
  getFirstTable :: (ts :& x) -> t
getFirstTable (ts
ts :& x
_) = forall t ts. GetFirstTable t ts => ts -> t
getFirstTable ts
ts

-- | Get the first table of a given type from a chain of tables joined with `(:&)`.
--
-- This can make it easier to write queries with a large number of join clauses:
--
-- @
-- select $ do
-- (people :& followers :& blogPosts) <-
--     from $ table \@Person
--     \`innerJoin` table \@Follow
--     \`on\` (\\(person :& follow) ->
--             person ^. PersonId ==. follow ^. FollowFollowed)
--     \`innerJoin` table \@BlogPost
--     \`on\` (\\((getTable \@Follow -> follow) :& blogPost) ->
--             blogPost ^. BlogPostAuthorId ==. follow ^. FollowFollower)
-- where_ (people1 ^. PersonName ==. val \"John\")
-- pure (followers, people2)
-- @
--
-- This example is a bit trivial, but once you've joined five or six tables it
-- becomes enormously helpful. The above example uses a @ViewPattern@ to call
-- the function and assign the variable directly, but you can also imagine it
-- being written like this:
--
-- @
--     \`on\` (\\(prev :& blogPost) ->
--             let
--                 follow = getTable \@Follow prev
--              in
--                 blogPost ^. BlogPostAuthorId ==. follow ^. FollowFollower)
-- @
--
-- This function will pluck out the first table that matches the applied type,
-- so if you join on the same table multiple times, it will always select the
-- first one provided.
--
-- The `(:&)` operator associates so that the left hand side can be a wildcard
-- for an arbitrary amount of nesting, and the "most recent" or "newest" table
-- in a join sequence is always available on the rightmost - so @(prev :& bar)@
-- is a pattern that matches @bar@ table (the most recent table added) and
-- @prev@ tables (all prior tables in the join match).
--
-- By calling 'getTable' on the @prev@, you can select exactly the table you
-- want, allowing you to omit a large number of spurious pattern matches.
-- Consider a query that does several @LEFT JOIN@ on a first table:
--
-- @
-- SELECT *
-- FROM person
-- LEFT JOIN car
--   ON person.id = car.person_id
-- LEFT JOIN bike
--   ON person.id = bike.person_id
-- LEFT JOIN food
--   ON person.id = food.person_id
-- LEFT JOIN address
--   ON person.id = address.person_id
-- @
--
-- The final 'on' clause in esqueleto would look like this:
--
-- @
--     \`on\` do
--         \\(person :& _car :& _bike :& _food :& address) ->
--             person.id ==. address.personId
-- @
--
-- First, we can change it to a @prev :& newest@ match. We can do this because
-- of the operator associativity. This is kind of like how a list @:@ operator
-- associates, but in the other direction: @a : (b : c) = a : b : c@.
--
-- @
--     \`on\` do
--         \\(prev :& address) ->
--             let (person :& _car :& _bike :& _food) = prev
--              in person.id ==. address.personId
-- @
--
-- Then, we can use 'getTable' to select the @Person@ table directly, instead of
-- pattern matching manually.
--
-- @
--     \`on\` do
--         \\(prev :& address) ->
--             let person = getTable \@Person prev
--              in person.id ==. address.personId
-- @
--
-- Finally, we can use a @ViewPattern@ language extension to "inline" the
-- access.
--
-- @
--     \`on\` do
--         \\((getTable \@Person -> person) :& address) ->
--            person.id ==. address.personId
-- @
--
-- With this form, you do not need to be concerned about the number and wildcard
-- status of tables that do not matter to the specific @ON@ clause.
--
-- @since 3.5.9.0
getTable :: forall t ts. GetFirstTable (SqlExpr (Entity t)) ts
         => ts
         -> SqlExpr (Entity t)
getTable :: forall t ts.
GetFirstTable (SqlExpr (Entity t)) ts =>
ts -> SqlExpr (Entity t)
getTable = forall t ts. GetFirstTable t ts => ts -> t
getFirstTable

-- | A variant of `getTable` that operates on possibly-null entities.
--
-- @since 3.5.9.0
getTableMaybe :: forall t ts. GetFirstTable (SqlExpr (Maybe (Entity t))) ts
              => ts
              -> SqlExpr (Maybe (Entity t))
getTableMaybe :: forall t ts.
GetFirstTable (SqlExpr (Maybe (Entity t))) ts =>
ts -> SqlExpr (Maybe (Entity t))
getTableMaybe = forall t ts. GetFirstTable t ts => ts -> t
getFirstTable

------ Compatibility for old syntax

data Lateral
data NotLateral

type family IsLateral a where
    IsLateral (a -> SqlQuery b, c) = Lateral
    IsLateral (a -> SqlQuery b) = Lateral
    IsLateral a = NotLateral

class DoInnerJoin lateral lhs rhs res | lateral rhs lhs -> res where
    doInnerJoin :: Proxy lateral -> lhs -> rhs -> From res

instance ( ToFrom a a'
         , ToFrom b b'
         , HasOnClause rhs (a' :& b')
         , rhs ~ (b, (a' :& b') -> SqlExpr (Value Bool))
         ) => DoInnerJoin NotLateral a rhs (a' :& b') where
    doInnerJoin :: Proxy NotLateral -> a -> rhs -> From (a' :& b')
doInnerJoin Proxy NotLateral
_ = forall a a' b b' rhs.
(ToFrom a a', ToFrom b b', HasOnClause rhs (a' :& b'),
 rhs ~ (b, (a' :& b') -> SqlExpr (Value Bool))) =>
a -> rhs -> From (a' :& b')
innerJoin

instance ( ToFrom a a'
         , SqlSelect b r
         , ToAlias b
         , ToAliasReference b
         , d ~ (a' :& b)
         ) => DoInnerJoin Lateral a (a' -> SqlQuery b, d -> SqlExpr (Value Bool)) d where
    doInnerJoin :: Proxy Lateral
-> a -> (a' -> SqlQuery b, d -> SqlExpr (Value Bool)) -> From d
doInnerJoin Proxy Lateral
_ = forall a a' rhs b r.
(ToFrom a a', HasOnClause rhs (a' :& b), SqlSelect b r, ToAlias b,
 ToAliasReference b,
 rhs ~ (a' -> SqlQuery b, (a' :& b) -> SqlExpr (Value Bool))) =>
a -> rhs -> From (a' :& b)
innerJoinLateral

instance ( DoInnerJoin lateral lhs rhs r, lateral ~ IsLateral rhs )
           => ToFrom (InnerJoin lhs rhs) r where
     toFrom :: InnerJoin lhs rhs -> From r
toFrom (InnerJoin lhs
a rhs
b) = forall lateral lhs rhs res.
DoInnerJoin lateral lhs rhs res =>
Proxy lateral -> lhs -> rhs -> From res
doInnerJoin (forall {k} (t :: k). Proxy t
Proxy @lateral) lhs
a rhs
b

class DoLeftJoin lateral lhs rhs res | lateral rhs lhs -> res where
    doLeftJoin :: Proxy lateral -> lhs -> rhs -> From res

instance ( ToFrom a a'
         , ToFrom b b'
         , ToMaybe b'
         , ToMaybeT b' ~ mb
         , HasOnClause rhs (a' :& mb)
         , rhs ~ (b, (a' :& mb) -> SqlExpr (Value Bool))
         ) => DoLeftJoin NotLateral a rhs (a' :& mb) where
    doLeftJoin :: Proxy NotLateral -> a -> rhs -> From (a' :& mb)
doLeftJoin Proxy NotLateral
_ = forall a a' b b' rhs.
(ToFrom a a', ToFrom b b', ToMaybe b',
 HasOnClause rhs (a' :& ToMaybeT b'),
 rhs ~ (b, (a' :& ToMaybeT b') -> SqlExpr (Value Bool))) =>
a -> rhs -> From (a' :& ToMaybeT b')
leftJoin

instance ( ToFrom a a'
         , ToMaybe b
         , d ~ (a' :& ToMaybeT b)
         , SqlSelect b r
         , ToAlias b
         , ToAliasReference b
         ) => DoLeftJoin Lateral a (a' -> SqlQuery b, d -> SqlExpr (Value Bool)) d where
    doLeftJoin :: Proxy Lateral
-> a -> (a' -> SqlQuery b, d -> SqlExpr (Value Bool)) -> From d
doLeftJoin Proxy Lateral
_ = forall a a' b r rhs.
(ToFrom a a', SqlSelect b r, HasOnClause rhs (a' :& ToMaybeT b),
 ToAlias b, ToAliasReference b, ToMaybe b,
 rhs
 ~ (a' -> SqlQuery b,
    (a' :& ToMaybeT b) -> SqlExpr (Value Bool))) =>
a -> rhs -> From (a' :& ToMaybeT b)
leftJoinLateral

instance ( DoLeftJoin lateral lhs rhs r, lateral ~ IsLateral rhs )
           => ToFrom (LeftOuterJoin lhs rhs) r where
     toFrom :: LeftOuterJoin lhs rhs -> From r
toFrom (LeftOuterJoin lhs
a rhs
b) = forall lateral lhs rhs res.
DoLeftJoin lateral lhs rhs res =>
Proxy lateral -> lhs -> rhs -> From res
doLeftJoin (forall {k} (t :: k). Proxy t
Proxy @lateral) lhs
a rhs
b

class DoCrossJoin lateral lhs rhs res | lateral lhs rhs -> res where
    doCrossJoin :: Proxy lateral -> lhs -> rhs -> From res

instance (ToFrom a a', ToFrom b b') => DoCrossJoin NotLateral a b (a' :& b') where
    doCrossJoin :: Proxy NotLateral -> a -> b -> From (a' :& b')
doCrossJoin Proxy NotLateral
_ = forall a a' b b'.
(ToFrom a a', ToFrom b b') =>
a -> b -> From (a' :& b')
crossJoin
instance (ToFrom a a', SqlSelect b r, ToAlias b, ToAliasReference b)
  => DoCrossJoin Lateral a (a' -> SqlQuery b) (a' :& b) where
    doCrossJoin :: Proxy Lateral -> a -> (a' -> SqlQuery b) -> From (a' :& b)
doCrossJoin Proxy Lateral
_ = forall a a' b r.
(ToFrom a a', SqlSelect b r, ToAlias b, ToAliasReference b) =>
a -> (a' -> SqlQuery b) -> From (a' :& b)
crossJoinLateral

instance (DoCrossJoin lateral lhs rhs r, IsLateral rhs ~ lateral)
  => ToFrom (CrossJoin lhs rhs) r where
    toFrom :: CrossJoin lhs rhs -> From r
toFrom (CrossJoin lhs
a rhs
b) = forall lateral lhs rhs res.
DoCrossJoin lateral lhs rhs res =>
Proxy lateral -> lhs -> rhs -> From res
doCrossJoin (forall {k} (t :: k). Proxy t
Proxy @lateral) lhs
a rhs
b

instance ( ToFrom a a'
         , ToFrom b b'
         , ToMaybe a'
         , ToMaybeT a' ~ ma
         , HasOnClause rhs (ma :& b')
         , ErrorOnLateral b
         , rhs ~ (b, (ma :& b') -> SqlExpr (Value Bool))
         ) => ToFrom (RightOuterJoin a rhs) (ma :& b') where
    toFrom :: RightOuterJoin a rhs -> From (ma :& b')
toFrom (RightOuterJoin a
a rhs
b) = forall a a' b b' rhs.
(ToFrom a a', ToFrom b b', ToMaybe a',
 HasOnClause rhs (ToMaybeT a' :& b'),
 rhs ~ (b, (ToMaybeT a' :& b') -> SqlExpr (Value Bool))) =>
a -> rhs -> From (ToMaybeT a' :& b')
rightJoin a
a rhs
b

instance ( ToFrom a a'
         , ToFrom b b'
         , ToMaybe a'
         , ToMaybeT a' ~ ma
         , ToMaybe b'
         , ToMaybeT b' ~ mb
         , HasOnClause rhs (ma :& mb)
         , ErrorOnLateral b
         , rhs ~ (b, (ma :& mb) -> SqlExpr (Value Bool))
         ) => ToFrom (FullOuterJoin a rhs) (ma :& mb) where
    toFrom :: FullOuterJoin a rhs -> From (ma :& mb)
toFrom (FullOuterJoin a
a rhs
b) = forall a a' b b' rhs.
(ToFrom a a', ToFrom b b', ToMaybe a', ToMaybe b',
 HasOnClause rhs (ToMaybeT a' :& ToMaybeT b'),
 rhs ~ (b, (ToMaybeT a' :& ToMaybeT b') -> SqlExpr (Value Bool))) =>
a -> rhs -> From (ToMaybeT a' :& ToMaybeT b')
fullOuterJoin a
a rhs
b