{-# OPTIONS_CYMAKE -Wno-incomplete-patterns #-}

module Spicey.ControllerGeneration where

import AbstractCurry.Types
import AbstractCurry.Build
import Char(toLower)
import Database.ERD
import Database.ERD.Goodies

import Spicey.GenerationHelper

-- Name of entity-specific authorization module:
enauthModName :: String
enauthModName = "System.AuthorizedActions"

-- Name of module defining the default controller:
defCtrlModName :: String
defCtrlModName = "Controller.DefaultController"

-- "main"-function
generateControllersForEntity :: String -> [Entity] -> Entity
                             -> [Relationship]
                             -> CurryProg
generateControllersForEntity erdname allEntities
                             (Entity ename attrlist) relationships =
 simpleCurryProg
  (controllerModuleName ename)
  -- imports:
  [ spiceyModule, "HTML.Base", "Time"
  , erdname, viewModuleName ename
  , "Maybe", sessionInfoModule, authorizationModule, enauthModName
  , "Config.UserProcesses",
   entitiesToHtmlModule erdname]
  [] -- typedecls
  -- functions
  (
    [
     -- controller for dispatching to various controllers:
     mainController erdname (Entity ename attrlist) relationships allEntities,
     -- controller for providing a page to enter new entity data:
     newController erdname (Entity ename attrlist) relationships allEntities,
     -- transaction for saving data in new entity:
     createTransaction erdname (Entity ename attrlist)
                               relationships allEntities,
     -- controller to show an existing record in a form to edit
     editController erdname (Entity ename attrlist) relationships allEntities,
     -- transaction to update a record with the given data
     updateTransaction erdname (Entity ename attrlist)
                               relationships allEntities,
     -- controller to delete an entity with the given data
     deleteController erdname (Entity ename attrlist)
                              relationships allEntities,
     -- transaction to delete an entity with the given data
     deleteTransaction erdname (Entity ename attrlist)
                               relationships allEntities,
     -- controller to list all entities:
     listController erdname (Entity ename attrlist) relationships allEntities,
     -- controller to show entites:
     showController erdname (Entity ename attrlist) relationships allEntities
   ] ++
    (manyToManyAddOrRemove erdname (Entity ename attrlist) (manyToMany allEntities (Entity ename attrlist)) allEntities) ++
    --(getAll erdname (Entity ename attrlist) (manyToOne (Entity ename attrlist) relationships) allEntities) ++
    --(getAll erdname (Entity ename attrlist) (manyToMany allEntities (Entity ename attrlist)) allEntities) ++
    --(manyToManyGetRelated erdname (Entity ename attrlist) (manyToMany allEntities (Entity ename attrlist)) allEntities) ++
    (manyToOneGetRelated erdname (Entity ename attrlist) (manyToOne (Entity ename attrlist) relationships) allEntities relationships)
  )
  [] -- opdecls


-- erdname: name of the entity-relationship-specification
-- entity: the entity to generate a controller for
type ControllerGenerator = String -> Entity -> [Relationship] -> [Entity] -> CFuncDecl

-- Generates the main controller that dispatches to the various
-- subcontrollers according to the URL parameters.
mainController :: ControllerGenerator
mainController erdname (Entity entityName _) _ _ =
  controllerFunction
  ("Choose the controller for a "++entityName++
   " entity according to the URL parameter.")
  entityName "main" 0
    controllerType -- function type
    [simpleRule [] -- no arguments
      (CDoExpr
         [CSPat (CPVar (1,"args"))
                (constF (spiceyModule,"getControllerParams")),
          CSExpr
           (CCase CRigid (CVar (1,"args"))
            ([cBranch (listPattern [])
                      (constF (controllerFunctionName entityName "list")),
              cBranch (listPattern [stringPattern "list"])
                      (constF (controllerFunctionName entityName "list")),
              cBranch (listPattern [stringPattern "new"])
                      (constF (controllerFunctionName entityName "new")),
              cBranch (listPattern [stringPattern "show", CPVar (2,"s")])
                (applyF (spiceyModule,"applyControllerOn")
                  [readKey,
                   getEntityOp,
                   constF (controllerFunctionName entityName "show")]),
              cBranch (listPattern [stringPattern "edit", CPVar (2,"s")])
                (applyF (spiceyModule,"applyControllerOn")
                  [readKey,
                   getEntityOp,
                   constF (controllerFunctionName entityName "edit")]),
              cBranch (listPattern [stringPattern "delete", CPVar (2,"s")])
                (applyF (spiceyModule,"applyControllerOn")
                  [readKey,
                   getEntityOp,
                   constF (controllerFunctionName entityName "delete")]),
              cBranch (CPVar (3,"_"))
                 (applyF (spiceyModule, "displayError")
                         [string2ac "Illegal URL"])])
          )
         ]
      )]
 where
  readKey     = applyF (erdname,"read"++entityName++"Key") [CVar (2,"s")]
  getEntityOp = applyF (pre ".")
                       [constF (erdname,"runJustT"),
                        constF (erdname,"get"++entityName)]

-- generates a controller to show a form to create a new entity
-- the input is then passed to the create controller
-- only has to call the blank entry form and pass the create controller
newController :: ControllerGenerator
newController erdname (Entity entityName attrList) relationships allEntities =
  let
    manyToManyEntities = manyToMany allEntities (Entity entityName attrList)
    manyToOneEntities  = manyToOne (Entity entityName attrList) relationships
    withCTime          = hasDateAttribute attrList
    infovar            = (0,"sinfo")
    ctimevar           = (1,"ctime")
  in
    controllerFunction
    ("Shows a form to create a new "++entityName++" entity.")
    entityName "new" 0
      controllerType -- function type
      [ -- rules
       simpleRule [] -- no arguments
        (applyF (pre "$")
            [applyF checkAuthorizationFunc
              [applyF (enauthModName,lowerFirst entityName++"OperationAllowed")
                [constF (authorizationModule,"NewEntity")]],
             CLambda [CPVar infovar] $
              CDoExpr (
              (map
                (\ (ename, num) ->
                   CSPat (CPVar (num,"all"++ename++"s"))
                         (applyF (erdname,"runQ")
                                 [constF (erdname,"queryAll"++ename++"s")])
                )
                (zip (manyToOneEntities ++ manyToManyEntities) [2..])
              ) ++
              (if withCTime
               then [CSPat (CPVar ctimevar)
                           (constF ("Time","getClockTime"))]
               else []) ++
              [
                CSExpr (
                  applyF (pre "return")
                   [applyF (viewFunctionName entityName "blank")
                     ([CVar infovar] ++
                      (if withCTime then [CVar ctimevar] else []) ++
                      map (\ (ename, num) -> CVar (num, "all"++ename++"s"))
                           (zip (manyToOneEntities ++ manyToManyEntities)
                                [2..]) ++
                      [CLambda [CPVar (200,"entity")]
                        (applyF (spiceyModule,"transactionController")
                          [applyF (erdname,"runT")
                            [applyF (transFunctionName entityName "create")
                                    [CVar (200,"entity")]],
                           applyF (spiceyModule,"nextInProcessOr")
                                  [callEntityListController entityName,
                                   constF (pre "Nothing")]]),
                       callEntityListController entityName])
                  ]
                )
              ]
            )
           ]
          )]

createTransaction :: ControllerGenerator
createTransaction erdname (Entity entityName attrList) relationships allEntities =
  let
    noPKeys            = (filter notPKey attrList)
--    foreignKeys = (filter isForeignKey attrList)
    notGeneratedAttributes = filter (\attr -> (not (isForeignKey attr))
                                              && (notPKey attr))     attrList
    parameterList      = map (\(Attribute name _ _ _) -> lowerFirst name)
                             (filter (not . isForeignKey) noPKeys)
    manyToManyEntities = manyToMany allEntities (Entity entityName attrList)
    manyToOneEntities  = manyToOne (Entity entityName attrList) relationships
  in
    stCmtFunc
    ("Transaction to persist a new "++entityName++" entity to the database.")
    (transFunctionName entityName "create")
    1 Private
      (tupleType (map attrType notGeneratedAttributes ++
                  map ctvar manyToOneEntities ++
                  map (listType . ctvar) manyToManyEntities)
        ~> applyTC (dbconn "DBAction") [baseType (pre "()")])
      [simpleRule
        [tuplePattern
          (map (\ (param, varId) -> CPVar (varId, param))
               (zip (parameterList ++ map lowerFirst manyToOneEntities ++
                     map (\e -> (lowerFirst e) ++ "s") manyToManyEntities)
                     [1..]))
        ] -- parameter list for controller
        (applyF (dbconn ">+=")
           [applyF (entityConstructorFunction erdname (Entity entityName attrList) relationships)
                       (map (\ ((Attribute name dom key null), varId) ->
                          if (isForeignKey (Attribute name dom key null))
                            then applyF (erdname, (lowerFirst (getReferencedEntityName dom))++"Key")
                                        [CVar (varId, lowerFirst (getReferencedEntityName dom))]
                            else let cv = CVar (varId, lowerFirst name)
                                  in if hasDefault dom && not (isStringDom dom)
                                        && not null
                                     then applyF (pre "Just") [cv]
                                     else cv)
                          (zip noPKeys [1..])
                        ),
            CLambda [cpvar "newentity"]
             (foldr1 (\a b -> applyF (dbconn ">+") [a,b])
              (map (\name -> applyF (controllerModuleName entityName,
                                     "add"++(linkTableName entityName name allEntities))
                                    [cvar (lowerFirst name ++ "s"),
                                     cvar "newentity"])
                   manyToManyEntities ++
               [applyF (pre "return") [constF (pre "()")]])
             )
           ]
           )]

editController :: ControllerGenerator
editController erdname (Entity entityName attrList) relationships allEntities =
  let
    manyToManyEntities = manyToMany allEntities (Entity entityName attrList)
    manyToOneEntities  = manyToOne (Entity entityName attrList) relationships
    pvar               = (0, lowerFirst entityName ++ "ToEdit")
    infovar            = (1, "sinfo")
  in
    controllerFunction
    ("Shows a form to edit the given "++entityName++" entity.")
    entityName "edit" 1
      (baseType (erdname,entityName) ~> controllerType
      )
      [simpleRule [CPVar pvar] -- parameterlist for controller
        (applyF (pre "$")
            [applyF checkAuthorizationFunc
              [applyF (enauthModName,lowerFirst entityName++"OperationAllowed")
                [applyF (authorizationModule,"UpdateEntity") [CVar pvar]]],
             CLambda [CPVar infovar] $
              CDoExpr (
              (map
                (\ (ename, num) ->
                      CSPat (CPVar (num,"all"++ename++"s"))
                            (applyF (erdname,"runQ")
                                    [constF (erdname,"queryAll"++ename++"s")])
                )
                (zip (manyToOneEntities ++ manyToManyEntities) [1..])
              ) ++
              (map
                (\ (ename, num) -> CSPat (CPVar (num,(lowerFirst (fst $ relationshipName entityName ename relationships))++ename))
                                (
                                  applyF (erdname,"runJustT") [
                                    applyF (controllerModuleName entityName,"get"++(fst $ relationshipName entityName ename relationships)++ename) [CVar pvar]
                                  ]
                                )
                )
                (zip (manyToOneEntities) [1..])
              ) ++
              (map
                (\ (ename, num) -> CSPat (CPVar (num,(lowerFirst (linkTableName entityName ename allEntities))++ename++"s"))
                                (
                                  applyF (erdname,"runJustT") [
                                    applyF (controllerModuleName entityName,"get"++entityName++ename++"s") [CVar pvar]
                                  ]
                                )
                )
                (zip (manyToManyEntities) [1..])
              ) ++
              [CSExpr (
                 applyF (pre "return")
                  [applyF (viewFunctionName entityName "edit")
                     ([CVar infovar,
                       tupleExpr
                        (
                          [CVar pvar] ++
                          (map (\ (ename, num) ->
                                 CVar (num,lowerFirst (linkTableName entityName
                                                       ename allEntities)
                                        ++ename++"s"))
                               (zip (manyToManyEntities) [1..]))
                        )
                      ] ++
                      (map
                        (\ (ename, num) ->
                               CVar (num,lowerFirst (fst $ relationshipName
                                            entityName ename relationships)
                                         ++ ename))
                        (zip (manyToOneEntities) [1..])
                      ) ++
                      ((map (\ (ename, num) -> CVar (num, "all"++ename++"s"))
                            (zip (manyToOneEntities ++ manyToManyEntities)
                                 [1..])) ++
                      [CLambda [CPVar (200,"entity")]
                        (applyF (spiceyModule,"transactionController")
                          [applyF (erdname,"runT")
                            [applyF (transFunctionName entityName "update")
                                    [CVar (200,"entity")]],
                           applyF (spiceyModule,"nextInProcessOr")
                                  [callEntityListController entityName,
                                   constF (pre "Nothing")]]),
                       callEntityListController entityName]
                      )
                    )
                  ]
                )
              ]
            )
           ]
          )]

updateTransaction :: ControllerGenerator
updateTransaction erdname (Entity entityName attrList) _ allEntities =
 let manyToManyEntities = manyToMany allEntities (Entity entityName attrList)
     -- manyToOneEntities = manyToOne (Entity entityName attrList) relationships
     -- noPKeys = (filter notPKey attrList)
  in
    stCmtFunc
    ("Transaction to persist modifications of a given "++entityName++" entity\n"++
     "to the database.")
    (transFunctionName entityName "update")
    2 Private
      (tupleType ([baseType (erdname, entityName)] ++
                   map (\name -> listType (ctvar name)) manyToManyEntities)
        ~> applyTC (dbconn "DBAction") [baseType (pre "()")]
      )
      [simpleRule
        [tuplePattern
               ([CPVar (0, lowerFirst entityName)] ++
                (map (\ (param, varId) -> CPVar (varId, param))
                     (zip (map (\e -> lowerFirst e ++ "s" ++
                                      linkTableName entityName e allEntities)
                               manyToManyEntities)
                          [1..])))
        ] -- parameter list for controller
        (foldr1 (\a b -> applyF (dbconn ">+") [a,b])
                  ([applyF (erdname, "update"++entityName)
                           [cvar (lowerFirst entityName)]] ++
                   (map  (\name ->
                            applyF (dbconn ">+=") [
                              applyF (controllerModuleName entityName,"get"++entityName++name++"s") [cvar (lowerFirst entityName)],
                              CLambda [CPVar(0, "old"++(linkTableName entityName name allEntities)++name++"s")] (applyF (controllerModuleName entityName, "remove"++(linkTableName entityName name allEntities)) [cvar ("old"++(linkTableName entityName name allEntities)++name++"s"), cvar (lowerFirst entityName)])
                            ]
                          )
                         manyToManyEntities
                        ) ++
                        (map (\name -> applyF (controllerModuleName entityName, "add"++(linkTableName entityName name allEntities)) [cvar ((lowerFirst name)++"s"++(linkTableName entityName name allEntities)), cvar (lowerFirst entityName)]) manyToManyEntities)
                      )
          )]

--- Generates controller to delete an entity after confirmation.
deleteController :: ControllerGenerator
deleteController erdname (Entity entityName _) _ _ =
  let entlc  = lowerFirst entityName  -- entity name in lowercase
      entvar = (0, entlc)             -- entity parameter for controller
  in
  controllerFunction
  ("Deletes a given "++entityName++" entity (after asking for confirmation)\n"++
   "and proceeds with the list controller.")
  entityName "delete" 1
  (baseType (erdname, entityName) ~> controllerType)
  [simpleRule [CPVar entvar]
    (applyF (pre "$")
       [applyF checkAuthorizationFunc
         [applyF (enauthModName,entlc++"OperationAllowed")
                 [applyF (authorizationModule,"DeleteEntity") [CVar entvar]]],
        CLambda [CPVar (0,"_")] $
         applyF (spiceyModule,"confirmController")
         [list2ac
           [applyF (html "h3")
             [list2ac
               [applyF (html "htxt")
                [applyF (pre "concat")
                 [list2ac [string2ac "Really delete entity \"",
                           applyF (entitiesToHtmlModule erdname,
                                   entlc++"ToShortView")
                                  [CVar entvar],
                           string2ac "\"?"]]]]]],
          applyF (spiceyModule,"transactionController")
            [applyF (erdname,"runT")
                    [applyF (transFunctionName entityName "delete")
                            [CVar entvar]],
             constF (controllerFunctionName entityName "list")],
          applyF (controllerFunctionName entityName "show")
                 [CVar entvar]]])]

--- Generates a transaction to delete an entity.
deleteTransaction :: ControllerGenerator
deleteTransaction erdname (Entity entityName attrList) _ allEntities =
  let manyToManyEntities = manyToMany allEntities (Entity entityName attrList)
      entlc  = lowerFirst entityName  -- entity name in lowercase
      entvar = (0, entlc)             -- entity parameter for trans.
  in
   stCmtFunc
    ("Transaction to delete a given "++entityName++" entity.")
    (transFunctionName entityName "delete")
    1 Private
    (baseType (erdname, entityName) ~>
                     applyTC (dbconn "DBAction") [baseType (pre "()")])
    [simpleRule
      [CPVar entvar] -- entity parameter for controller
      (foldr1 (\a b -> applyF (dbconn ">+") [a,b])
           (map (\name ->
                  applyF (dbconn ">+=")
                         [applyF (controllerModuleName entityName,
                                  "get"++entityName++name++"s")
                                 [CVar entvar],
                          CLambda [CPVar(0, "old"++(linkTableName entityName name allEntities)++name++"s")]
                            (applyF (controllerModuleName entityName,
                                     "remove"++(linkTableName entityName name allEntities))
                                    [cvar ("old"++(linkTableName entityName name allEntities)++name++"s"),
                                     CVar entvar ])
                        ]
                 )
                 manyToManyEntities ++
            [applyF (erdname, "delete"++entityName) [CVar entvar]]))]

listController :: ControllerGenerator
listController erdname (Entity entityName _) _ _ =
  let infovar = (0, "sinfo")
      entsvar = (1, (lowerFirst entityName)++"s")
   in
    controllerFunction
      ("Lists all "++entityName++" entities with buttons to show, delete,\n"++
       "or edit an entity.")
      entityName "list" 0
      controllerType
      [simpleRule [] -- no arguments
        (applyF (pre "$")
            [applyF checkAuthorizationFunc
              [applyF (enauthModName,lowerFirst entityName++"OperationAllowed")
                [applyF (authorizationModule,"ListEntities") []]],
             CLambda [CPVar infovar] $
              CDoExpr (
              [CSPat (CPVar entsvar)
                     (applyF (erdname,"runQ")
                             [constF (erdname,"queryAll"++entityName++"s")]),
               CSExpr (applyF (pre "return")
                             [applyF (viewFunctionName entityName "list")
                                     [CVar infovar, CVar entsvar]])
              ]
            )
           ]
          )]

showController :: ControllerGenerator
showController erdname (Entity entityName attrList) relationships allEntities =
  let manyToManyEntities = manyToMany allEntities (Entity entityName attrList)
      manyToOneEntities  = manyToOne (Entity entityName attrList) relationships
      pvar               = (0, lowerFirst entityName)
      infovar            = (1, "sinfo")
  in
    controllerFunction
    ("Shows a "++entityName++" entity.")
    entityName "show" 1
      (baseType (erdname,entityName) ~> controllerType)
      [simpleRule
        [CPVar pvar] -- parameterlist for controller
        (applyF (pre "$")
            [applyF checkAuthorizationFunc
              [applyF (enauthModName,lowerFirst entityName++"OperationAllowed")
                [applyF (authorizationModule,"ShowEntity") [CVar pvar]]],
             CLambda [CPVar infovar] $
              CDoExpr (
              (map (\ (ename, num) ->
                     CSPat (CPVar (num,lowerFirst
                                         (fst $ relationshipName entityName
                                               ename relationships) ++ ename))
                           (applyF (erdname,"runJustT")
                              [applyF (controllerModuleName entityName,
                                       "get"++ fst (relationshipName
                                                entityName ename relationships)
                                            ++ename)
                                      [CVar pvar]
                              ])
                   )
                   (zip (manyToOneEntities) [1..])
              ) ++
              (map (\ (ename, num) ->
                      CSPat (CPVar (num,lowerFirst (linkTableName entityName
                                                           ename allEntities)
                                        ++ename++"s"))
                            (applyF (erdname,"runJustT")
                               [applyF (controllerModuleName entityName,
                                        "get"++entityName++ename++"s")
                                       [CVar pvar]])
                   )
                   (zip (manyToManyEntities) [1..])
              ) ++
              [CSExpr (
                 applyF (pre "return")
                    [applyF (viewFunctionName entityName "show")
                       ([CVar infovar, CVar pvar] ++
                        (map (\ (ename, num) ->
                                CVar (num,lowerFirst (fst $ relationshipName
                                             entityName ename relationships)
                                           ++ ename))
                             (zip (manyToOneEntities) [1..])) ++
                        (map (\ (ename, num) ->
                               CVar (num,lowerFirst (linkTableName entityName
                                                       ename allEntities)
                                         ++ename++"s"))
                             (zip (manyToManyEntities) [1..])))
                    ])
              ])
            ]
          )
      ]

-- Code to call the list controller of an entity where the current
-- URL parameters are passed to this list controller.
callEntityListController :: String -> CExpr
callEntityListController entityName =
  constF (controllerFunctionName entityName "list")

manyToManyAddOrRemove :: String -> Entity -> [String] -> [Entity] -> [CFuncDecl]
manyToManyAddOrRemove erdname (Entity entityName _) entities allEntities =
    (map (addOrRemoveFunction "add" "new" entityName) entities) ++
    (map (addOrRemoveFunction "remove" "delete" entityName) entities)
  where
    addOrRemoveFunction :: String -> String -> String -> String -> CFuncDecl
    addOrRemoveFunction funcPrefix dbFuncPrefix e1 e2 =
      stCmtFunc
      (if (funcPrefix == "add")
        then ("Associates given entities with the "++entityName++" entity.")
        else ("Removes association to the given entities with the "++entityName++" entity."))
      (controllerModuleName e1, funcPrefix++(linkTableName e1 e2 allEntities))
      2
      Private
      (listType (ctvar e2) ~> ctvar e1 ~> applyTC (dbconn "DBAction")
                                                 [tupleType []])
      [simpleRule [CPVar (0, (lowerFirst e2)++"s"), CPVar (1, (lowerFirst e1))]
        (applyF (pre "mapM_")
           [CLambda [CPVar(2, "t")]
             (applyF (erdname, dbFuncPrefix++(linkTableName e1 e2 allEntities))
               [applyF (erdname, (lowerFirst e1)++"Key") [cvar (lowerFirst e1)],
                applyF (erdname, (lowerFirst e2)++"Key") [cvar "t"]]),
            cvar ((lowerFirst e2)++"s")])]

getAll :: String -> Entity -> [String] -> [Entity] -> [CFuncDecl]
getAll erdname (Entity entityName _) entities _ =
    map getAllFunction entities
  where
    getAllFunction :: String -> CFuncDecl
    getAllFunction foreignEntity =
      stCmtFunc
      ("Gets all "++foreignEntity++" entities.")
      (controllerModuleName entityName, "getAll"++foreignEntity++"s")
      0
      Private
      (ioType (listType (ctvar foreignEntity)))
      [simpleRule []
        (applyF (erdname,"runQ")
          [applyF (erdname,"queryAll")
            [CLambda [CPVar(0, take 1 (lowerFirst foreignEntity) )]
                     (CLetDecl [(CLocalVars [(1,"key")])]
                        (applyF (erdname, lowerFirst foreignEntity)
                                [cvar "key",
                                 cvar (take 1 (lowerFirst foreignEntity))]))
                    ]
            ]
       )
      ]

manyToManyGetRelated :: String -> Entity -> [String] -> [Entity] -> [CFuncDecl]
manyToManyGetRelated erdname (Entity entityName _) entities allEntities =
    map getRelatedFunction entities
  where
    getRelatedFunction :: String -> CFuncDecl
    getRelatedFunction foreignEntity =
      stCmtFunc
      ("Gets the associated "++foreignEntity++" entities for a given "++entityName++" entity.")
      (controllerModuleName entityName, "get"++(linkTableName entityName foreignEntity allEntities)++foreignEntity++"s")
      0
      Private
      (ctvar entityName ~> applyTC (dbconn "DBAction")
                                   [listType (ctvar foreignEntity)])
      [simpleRule [CPVar (1, (take 1 $ lowerFirst entityName)++foreignEntity)]
        (applyF (erdname,"queryAll")
          [CLambda [CPVar(0, take 1 (lowerFirst foreignEntity) )]
            (CLetDecl
               [CLocalVars [(1,(take 1 $ lowerFirst entityName)++"key"),
                            (2,(take 1 $ lowerFirst foreignEntity)++"key")]]
               (foldr (\a b -> applyF ("Dynamic", "<>") [a,b])
                 (applyF (erdname, lowerFirst (linkTableName entityName foreignEntity allEntities)) [cvar ((take 1 $ lowerFirst entityName)++"key"), cvar ((take 1 $ lowerFirst foreignEntity)++"key")])
                 [
                 (applyF (erdname, lowerFirst entityName) [cvar $ (take 1 $ lowerFirst entityName)++"key", cvar ((take 1 $ lowerFirst entityName)++foreignEntity)]),
                 (applyF (erdname, lowerFirst foreignEntity) [cvar $ (take 1 $ lowerFirst foreignEntity)++"key", cvar (take 1 (lowerFirst foreignEntity))])
                 ]
               )
            )
          ]
        )
      ]

manyToOneGetRelated :: String -> Entity -> [String] -> [Entity]
                    -> [Relationship] -> [CFuncDecl]
manyToOneGetRelated erdname (Entity entityName _) entities _ relationships =
    map getRelatedFunction entities
  where
    getRelatedFunction :: String -> CFuncDecl
    getRelatedFunction foreignEntity =
      let argvar  = (1, (take 1 $ lowerFirst entityName)++foreignEntity)
          rname   = fst (relationshipName entityName foreignEntity relationships)
          fkeysel = lowerFirst entityName++foreignEntity++rname++"Key"
      in
      stCmtFunc
      ("Gets the associated "++foreignEntity++" entity for a given "++
       entityName++" entity.")
      (controllerModuleName entityName,
       "get"++rname++foreignEntity)
      0
      Private
      ((ctvar entityName) ~> applyTC (dbconn "DBAction") [ctvar foreignEntity])
      [simpleRule [CPVar argvar]
                  (applyF (erdname,"get"++foreignEntity)
                          [applyF (erdname,fkeysel) [CVar argvar]])]

relationshipName :: String -> String -> [Relationship] -> (String, String)
relationshipName e1 e2 (rel:relrest)=
  case rel of
    (Relationship name [(REnd relE1 _ _), (REnd relE2 relName _)]) ->
      if ((relE1 == e1 && relE2 == e2) || (relE1 == e2 && relE2 == e1)) then (name, relName) else relationshipName e1 e2 relrest
relationshipName _ _ [] = error "relationshipName: relationship not found"
---- aux ---


displayErrorFunction :: QName
displayErrorFunction = (spiceyModule, "displayError")

entityConstructorFunction :: String -> Entity -> [Relationship] -> QName
entityConstructorFunction erdname (Entity entityName attrList) relationships =
  (erdname, "new" ++
    entityName ++ (newSuffix entityName attrList relationships)
  )

-- entityName: Name of entity the controller should be generated for
-- controllerType: the function of the generated Controller, e.g. "new", "edit", "list"
-- arity
-- functionType: the type of the controller function
-- rules: the rules defining the controller
controllerFunction :: String -> String -> String -> Int -> CTypeExpr -> [CRule]
                   -> CFuncDecl
controllerFunction description entityName controllerType arity functionType
                   rules =
  stCmtFunc description (controllerFunctionName entityName controllerType) arity
          (if controllerType `elem` ["main"]
           then Public
           else Private)
          functionType rules

getReferencedEntityName :: Domain -> String
getReferencedEntityName t =
  case t of KeyDom kd -> kd
            _         -> ""

relatedEntityNames :: Entity -> [Relationship] -> [String]
relatedEntityNames (Entity entityName attrlist) relationships =
  map (\(Relationship _ ((REnd name1 _ _):(REnd name2 _ _):[])) -> if (name1 == entityName) then name2 else name1) (relationshipsForEntity (Entity entityName attrlist) relationships)

-- gets all relationships 
relationshipsForEntity :: Entity -> [Relationship] -> [Relationship]
relationshipsForEntity (Entity entityName _) relationships =
  filter (\(Relationship _ ((REnd name1 _ _):(REnd name2 _ _):[])) -> name1 == entityName || name2 == entityName) (filter (not . isGeneratedR) relationships)

------ from ERD CodeGeneration

newSuffix :: String -> [Attribute] -> [Relationship] -> String
newSuffix eName attrs rels =
  let
    generatedRs = filter isGeneratedR rels
    exactRs  = filter isExactB  generatedRs --(i,i), i>1
    maxRs    = filter isMaxB    generatedRs --(0,i), i>1
    minMaxRs = filter isMinMaxB generatedRs --(i,j), i>0, j>i
  in
    concatMap ("With"++)
              (map attributeName (filter isForeignKey attrs)) ++
    if (length (exactRs ++ maxRs ++ minMaxRs))==0
    then ""
    else concatMap (\k->"With"++k++"Keys")
                   (map (relatedRelation eName)
                        (exactRs++maxRs++minMaxRs))
  where
    isExactB (Relationship _ [REnd _ _ _, REnd _ _ c]) =
      case c of Exactly i -> i>1
                _         -> False
    isMaxB (Relationship _ [REnd _ _ _, REnd _ _ c]) =
      case c of (Between 0 (Max i)) -> i>1
                _                   -> False
    isMinMaxB (Relationship _ [REnd _ _ _, REnd _ _ c]) =
      case c of (Between i (Max j)) -> i>0 && j>i
                _                   -> False

isGeneratedR :: Relationship -> Bool
isGeneratedR (Relationship n _) = n == ""

-- extracts the name of the relationship related to a given entity name
relatedRelation :: String -> Relationship -> String
relatedRelation en (Relationship _ [REnd en1 _ _, REnd en2 _ _]) =
  if en==en1 then en2 else en1

relationshipsForEntityName :: String -> [Relationship] -> [Relationship]
relationshipsForEntityName ename rels = filter endsIn rels
 where
  endsIn (Relationship _ ends) = any (\ (REnd n _ _) -> ename == n) ends

------------------------------------------------------------------------
-- Generate the module defining the default controller.
generateDefaultController :: String -> [Entity] -> CurryProg
generateDefaultController _ (Entity ename _:_) = simpleCurryProg
  defCtrlModName
  [controllerModuleName ename, spiceyModule] -- imports
  [] -- typedecls
  -- functions
  [stCmtFunc
    "The default controller of the application."
    (defCtrlModName,"defaultController")
    1
    Public
    controllerType
    [simpleRule []
       (constF (controllerModuleName ename, "main"++ename++"Controller"))]
  ]
  [] -- opdecls

------------------------------------------------------------------------
-- Auxiliaries:

getUserSessionInfoFunc :: CExpr
getUserSessionInfoFunc = constF (sessionInfoModule,"getUserSessionInfo")

checkAuthorizationFunc :: QName
checkAuthorizationFunc = (authorizationModule,"checkAuthorization")

------------------------------------------------------------------------