From 223c7bede8577c54c1460df05b8949fc47096d17 Mon Sep 17 00:00:00 2001
From: = <=>
Date: Fri, 11 Sep 2015 11:01:06 +0200
Subject: [PATCH] Rule Engine scaffold

---
 Main.hs       | 13 ++++++++
 RuleEngine.hs | 84 +++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 97 insertions(+)
 create mode 100755 Main.hs
 create mode 100755 RuleEngine.hs

diff --git a/Main.hs b/Main.hs
new file mode 100755
index 0000000..cd43315
--- /dev/null
+++ b/Main.hs
@@ -0,0 +1,13 @@
+module Main where
+
+import RuleEngine
+
+main = do
+    let operator = InsideOp (4::Int)
+    let coupleValue = CoupleVal (2::Int) (5::Int)
+    let boxing = Template coupleValue operator
+    let condition = Condition "Alaintérieure" boxing
+    let rule = addEvaluable (Rule []) condition
+    let ruleEngine = addRule (RuleEngine []) rule
+
+    print (evalRuleEngine ruleEngine)
\ No newline at end of file
diff --git a/RuleEngine.hs b/RuleEngine.hs
new file mode 100755
index 0000000..b09004e
--- /dev/null
+++ b/RuleEngine.hs
@@ -0,0 +1,84 @@
+{-# LANGUAGE MultiParamTypeClasses, FlexibleInstances #-}
+
+module RuleEngine
+(
+-- Operators
+    InsideOp(InsideOp),
+    InferiorOp(InferiorOp),
+
+-- Template data
+    Unival(Unival),
+    CoupleVal(CoupleVal),
+
+-- Template (data + operator)
+    Template(Template),
+
+-- Condition
+    Condition(Condition),
+
+    EvalTemplate(evalTemplate),
+
+-- Rule
+    Rule(Rule),
+    addEvaluable,
+    evalRule,
+
+-- RuleEngine
+    RuleEngine(RuleEngine),
+    addRule,
+    evalRuleEngine
+) where
+
+-- Operators
+
+data InsideOp e = InsideOp e
+data InferiorOp e  = InferiorOp e
+
+-- Template data
+
+data Unival x = Unival x
+data CoupleVal x = CoupleVal x x
+
+-- Template (data + operator)
+data Template dat op = Template dat op
+
+-- Condition
+
+data Condition evaluable = Condition String evaluable
+
+-- Eval type classe
+
+class EvalTemplate val op where
+    evalTemplate :: val -> op -> Bool
+
+class EvalCondition e where
+    evalCondition :: e -> Bool
+
+instance EvalTemplate (Unival e) (InsideOp i) where
+    evalTemplate val op = True
+
+instance Ord(x) => EvalTemplate (CoupleVal x) (InsideOp x) where
+    evalTemplate (CoupleVal x1 x2) (InsideOp ins) = ins >= x1 && ins <= x2
+
+instance (EvalTemplate dat op) =>  EvalCondition (Condition (Template dat op)) where
+    evalCondition (Condition str (Template v o)) = evalTemplate v o
+
+-- Rule
+
+data Rule evaluable = Rule [evaluable]
+
+addEvaluable :: EvalCondition(e) => Rule e -> e -> Rule e
+addEvaluable (Rule lst) val = Rule (val : lst)
+
+evalRule :: EvalCondition(e) => (Rule e) -> Bool
+evalRule (Rule evaluables) = foldr (\elem b -> evalCondition(elem) && b) True evaluables
+
+-- Rule Engine
+
+data RuleEngine evaluable = RuleEngine [Rule evaluable]
+
+addRule :: EvalCondition(evaluable) => RuleEngine evaluable -> Rule evaluable -> RuleEngine evaluable
+addRule (RuleEngine ruleList) rule = RuleEngine (rule : ruleList)
+
+evalRuleEngine :: EvalCondition(evaluable) => RuleEngine evaluable -> Bool
+evalRuleEngine (RuleEngine rules) = foldr (\rule b -> evalRule(rule) && b) True rules
\ No newline at end of file