From 79dfae84547f2148b52c317c40bd672e3e52bd5d Mon Sep 17 00:00:00 2001
From: PHO <pho@cielonegro.org>
Date: Thu, 22 Apr 2010 19:28:46 +0900
Subject: [PATCH] wip

---
 Database/RRDtool.hs | 42 ++++++++++++++++++++++++++++++++++--------
 1 file changed, 34 insertions(+), 8 deletions(-)

diff --git a/Database/RRDtool.hs b/Database/RRDtool.hs
index 6e7b332..f588fdb 100644
--- a/Database/RRDtool.hs
+++ b/Database/RRDtool.hs
@@ -17,6 +17,7 @@ module Database.RRDtool
     , CommonSetOp(..)
     , VariableShiftPredictOp(..)
     , FixedShiftPredictOp(..)
+    , CommonValue(..)
     , IterativeValue(..)
     , AggregativeUnaryOp(..)
 
@@ -155,7 +156,7 @@ dsTest = COMPUTE {
            dsName = "foo"
 --         , dsExpr = Previous :<: Const 100
 --         , dsExpr = Var "foo" :<: Const 100
-           , dsExpr = Average (Const 100 .*. Const 200 .*. HNil)
+           , dsExpr = AverageOf (Const 100 .*. Const 200 .*. HNil)
          }
 
 class (Show e, Eq e) => Expr e
@@ -163,7 +164,6 @@ class Expr e => CommonExpr e
 class Expr e => IterativeExpr e
 class Expr e => AggregativeExpr e
 instance CommonExpr e => IterativeExpr e
-instance CommonExpr e => AggregativeExpr e
 
 class (Show es, Eq es, HList es) => ExprSet es
 instance ExprSet HNil
@@ -244,7 +244,7 @@ instance (CommonExpr a, CommonExpr b, CommonExpr c)
 -- multiple values onto the stack...
 
 data CommonSetOp es
-    = Average !es
+    = AverageOf !es
     deriving (Show, Eq, Ord)
 instance ExprSet es => Expr (CommonSetOp es)
 instance CommonExprSet es => CommonExpr (CommonSetOp es)
@@ -267,19 +267,45 @@ instance (Expr sm, Expr w)
 instance (CommonExpr sm, CommonExpr w)
     => CommonExpr (FixedShiftPredictOp sm w)
 
+-- Common special values
+data CommonValue
+    = Unknown
+    | Infinity
+    | NegativeInfinity
+    | Now
+    deriving (Show, Eq, Ord)
+instance Expr CommonValue
+instance CommonExpr CommonValue
+
 -- Iterative special values
 data IterativeValue
     = Previous
+    | PreviousOf !Variable
+    | Count
+    | TakenTime
+    | TakenLocalTime
     deriving (Show, Eq, Ord)
 instance Expr IterativeValue
 instance IterativeExpr IterativeValue
 
--- Aggregative operators
-data AggregativeUnaryOp a
-    = Maximum !a
+-- Aggregative operators (fairly restricted due to rrdtool's
+-- restriction)
+data AggregativeUnaryOp
+    = Maximum    !Variable
+    | Minimum    !Variable
+    | Average    !Variable
+    | StandardDeviation !Variable
+    | First      !Variable
+    | Last       !Variable
+    | Total      !Variable
+    | Percent    !Variable !Constant
+    | PercentNan !Variable !Constant
+    | LSLSlope   !Variable
+    | LSLInt     !Variable
+    | LSLCorrel  !Variable
     deriving (Show, Eq, Ord)
-instance Expr a => Expr (AggregativeUnaryOp a)
-instance AggregativeExpr a => AggregativeExpr (AggregativeUnaryOp a)
+instance Expr AggregativeUnaryOp
+instance AggregativeExpr AggregativeUnaryOp
 
 -- |The 'createRRD' function lets you set up new Round Robin Database
 -- (RRD) files. The file is created at its final, full size and filled
-- 
2.40.0