From d80ec9748b20888a1aae1828e1b622c6476e1992 Mon Sep 17 00:00:00 2001
From: Michael Orlitzky <michael@orlitzky.com>
Date: Sun, 1 Jun 2014 09:16:51 -0400
Subject: [PATCH] Add initial database code for TSN.XML.GameInfo.

---
 src/TSN/XML/GameInfo.hs | 105 +++++++++++++++++++++++++++++++++++-----
 1 file changed, 92 insertions(+), 13 deletions(-)

diff --git a/src/TSN/XML/GameInfo.hs b/src/TSN/XML/GameInfo.hs
index af622f0..375a77a 100644
--- a/src/TSN/XML/GameInfo.hs
+++ b/src/TSN/XML/GameInfo.hs
@@ -1,3 +1,10 @@
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE GADTs #-}
+{-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE TypeFamilies #-}
+
 -- | GameInfo represents a collection of DTDs that we don't really
 --   handle but want to make available. The raw XML gets stored in the
 --   database along with the XML_File_ID, but we don't parse any of it.
@@ -6,17 +13,31 @@
 --
 module TSN.XML.GameInfo (
   dtds,
-  from_xml )
+  parse_xml,
+  -- * WARNING: these are private but exported to silence warnings
+  GameInfoConstructor(..) )
 where
 
+-- System imports.
 import Data.Time.Clock ( UTCTime )
+import Database.Groundhog ( migrate )
+import Database.Groundhog.TH (
+  groundhog,
+  mkPersist )
 import Text.XML.HXT.Core ( XmlTree )
 import Text.XML.HXT.DOM.ShowXml ( xshow )
 
+-- Local imports.
+import TSN.Codegen ( tsn_codegen_config )
+import TSN.DbImport ( DbImport(..), ImportResult(..), run_dbmigrate )
 import TSN.Parse (
   parse_message,
   parse_xmlfid,
   parse_xml_time_stamp )
+import TSN.XmlImport ( XmlImport(..) )
+import Xml (
+  FromXml(..),
+  ToDb(..) )
 
 -- | The DTDs for everything that we consider "Game Info."
 --
@@ -28,16 +49,16 @@ dtds :: [String]
 dtds =
   [ "CBASK_Lineup_XML.dtd",
     "cbaskpreviewxml.dtd",
-    "cflpreviewxml.dtd",
+    "cflpreviewxml.dtd", -- missing DTD
     "Matchup_NBA_NHL_XML.dtd",
     "mlbpreviewxml.dtd",
     "MLB_Gaming_Matchup_XML.dtd",
-    "MLB.dtd",
+    "MLB.dtd", -- missing DTD
     "MLB_Lineup_XML.dtd",
     "MLB_Matchup_XML.dtd",
     "MLS_Preview_XML.dtd",
     "NBA_Gaming_Matchup_XML.dtd",
-    "NBA.dtd",
+    "NBA.dtd", -- missing DTD
     "NBA_Playoff_Matchup_XML.dtd",
     "NBALineupXML.dtd",
     "nbapreviewxml.dtd",
@@ -46,25 +67,83 @@ dtds =
     "NFL_NCAA_FB_Matchup_XML.dtd",
     "nhlpreviewxml.dtd",
     "recapxml.dtd",
-    "WorldBaseballPreviewXML.dtd" ]
+    "WorldBaseballPreviewXML.dtd" -- missing DTD
+  ]
 
 
--- | The data structure that holds the XML representation of a
---   GameInfo message.
+-- | XML representation of a GameInfo \<message\>.
 --
 data Message =
   Message {
-    dtd :: String,
-    xml_file_id :: Int,
-    time_stamp :: UTCTime,
-    xml :: String }
+    xml_dtd :: String,
+    xml_xml_file_id :: Int,
+    xml_time_stamp :: UTCTime,
+    xml_xml :: String }
   deriving (Eq, Show)
 
 
-from_xml :: String -> XmlTree -> Either String Message
-from_xml dtdname xmltree = do
+-- | Attempt to parse a 'Message' from an 'XmlTree'. If we cannot,
+--   we fail with an error message.
+--
+parse_xml :: String -> XmlTree -> Either String Message
+parse_xml dtdname xmltree = do
   xmlfid <- parse_xmlfid xmltree
   timestamp <- parse_xml_time_stamp xmltree
   message <- parse_message xmltree
   return $ Message dtdname (fromInteger xmlfid) timestamp (xshow [message])
 
+
+-- | Database representation of a 'Message'.
+--
+data GameInfo =
+  GameInfo {
+    db_dtd :: String,
+    db_xml_file_id :: Int,
+    db_time_stamp :: UTCTime,
+    db_xml :: String }
+
+
+instance ToDb Message where
+  -- | The database analogue of a 'Message' is an 'GameInfo'.
+  type Db Message = GameInfo
+
+instance FromXml Message where
+  -- | The XML to DB conversion is trivial here.
+  --
+  from_xml Message{..} = GameInfo {
+                           db_dtd = xml_dtd,
+                           db_xml_file_id = xml_xml_file_id,
+                           db_time_stamp = xml_time_stamp,
+                           db_xml = xml_xml }
+
+
+-- | This allows us to insert the XML representation 'Message'
+--   directly.
+--
+instance XmlImport Message
+
+
+--
+-- Database code
+--
+
+instance DbImport Message where
+  dbmigrate _ =
+    run_dbmigrate $ migrate (undefined :: GameInfo)
+
+  -- | We import a 'Message' by inserting the whole thing at
+  --   once. Nothing fancy going on here.
+  dbimport msg = do
+    insert_xml_ msg
+    return ImportSucceeded
+
+mkPersist tsn_codegen_config [groundhog|
+- entity: GameInfo
+  constructors:
+    - name: GameInfo
+      uniques:
+        - name: unique_game_info
+          type: constraint
+          # Prevent multiple imports of the same message.
+          fields: [db_xml_file_id]
+|]
-- 
2.43.2