From c861bf30555e18c6431cfadcf880db18eec7d20a Mon Sep 17 00:00:00 2001
From: "Davide Gessa (dakk)" <gessadavide@gmail.com>
Date: Wed, 18 Oct 2023 16:55:07 +0200
Subject: [PATCH] add operation

---
 qlasskit/ast2logic/t_expression.py |  9 ++++++++-
 qlasskit/types/__init__.py         | 10 +++++++++-
 qlasskit/types/qint.py             | 25 ++++++++++++++++++++-----
 qlasskit/types/qtype.py            |  6 ++++++
 test/test_qlassf_int.py            | 12 ++++++++++++
 5 files changed, 55 insertions(+), 7 deletions(-)

diff --git a/qlasskit/ast2logic/t_expression.py b/qlasskit/ast2logic/t_expression.py
index 71d27e2b..5a727008 100644
--- a/qlasskit/ast2logic/t_expression.py
+++ b/qlasskit/ast2logic/t_expression.py
@@ -199,7 +199,14 @@ def unfold(v_exps, op):
     elif isinstance(expr, ast.BinOp):
         # Add | Sub | Mult | MatMult | Div | Mod | Pow | LShift | RShift
         # | BitOr | BitXor | BitAnd | FloorDiv
-        raise exceptions.ExpressionNotHandledException(expr)
+        # print(ast.dump(expr))
+        tleft = translate_expression(expr.left, env)
+        tright = translate_expression(expr.right, env)
+        
+        if isinstance(expr.op, ast.Add):
+            return tleft[0].add(tleft, tright)
+        else:
+            raise exceptions.ExpressionNotHandledException(expr)
 
     # Call
     elif isinstance(expr, ast.Call):
diff --git a/qlasskit/types/__init__.py b/qlasskit/types/__init__.py
index 052d7bff..5296c2d7 100644
--- a/qlasskit/types/__init__.py
+++ b/qlasskit/types/__init__.py
@@ -15,7 +15,7 @@
 
 from typing import Any
 
-from sympy.logic import Not, Xor
+from sympy.logic import Not, Xor, And, Or
 
 
 def _neq(a, b):
@@ -26,6 +26,14 @@ def _eq(a, b):
     return Not(_neq(a, b))
 
 
+def _half_adder(a, b):  # Carry x Sum
+    return And(a, b), Xor(a, b)
+
+
+def _full_adder(c, a, b):  # Carry x Sum
+    return Or(And(a, b), And(b, c), And(a, c)), Xor(a, b, c)
+
+
 from .qtype import Qtype, TExp, TType  # noqa: F401, E402
 from .qbool import Qbool  # noqa: F401, E402
 from .qint import Qint, Qint2, Qint4, Qint8, Qint12, Qint16  # noqa: F401, E402
diff --git a/qlasskit/types/qint.py b/qlasskit/types/qint.py
index 4abf8aa7..2808810e 100644
--- a/qlasskit/types/qint.py
+++ b/qlasskit/types/qint.py
@@ -17,7 +17,7 @@
 from sympy import Symbol
 from sympy.logic import And, Not, Or, false, true
 
-from . import _eq, _neq
+from . import _eq, _full_adder, _neq
 from .qtype import Qtype, TExp
 
 
@@ -26,7 +26,10 @@ class Qint(int, Qtype):
 
     def __init__(self, value):
         super().__init__()
-        self.value = value
+        self.value = value % 2**self.BIT_SIZE
+        
+    def __add__(self, b):
+        return (self.value + b) % 2**self.BIT_SIZE
 
     @classmethod
     def from_bool(cls, v: List[bool]):
@@ -140,9 +143,21 @@ def gte(tleft: TExp, tcomp: TExp) -> TExp:
         """Compare two Qint for greater than - equal"""
         return (bool, Not(Qint.lt(tleft, tcomp)[1]))
 
-    # @staticmethod
-    # def add(tleft: TExp, tright: TExp) -> TExp:
-    #     """Add two Qint"""
+    # Operations
+
+    @classmethod
+    def add(cls, tleft: TExp, tright: TExp) -> TExp:
+        """Add two Qint"""
+        if len(tleft[1]) != len(tright[1]):  # TODO: handle this
+            raise Exception("Ints have differnt sizes")
+
+        carry = False
+        sums = []
+        for x in zip(tleft[1], tright[1]):
+            carry, sum = _full_adder(carry, x[0], x[1])
+            sums.append(sum)
+
+        return (cls, sums)
 
 
 class Qint2(Qint):
diff --git a/qlasskit/types/qtype.py b/qlasskit/types/qtype.py
index 1c7f7e2c..df9a4c5c 100644
--- a/qlasskit/types/qtype.py
+++ b/qlasskit/types/qtype.py
@@ -98,3 +98,9 @@ def lt(tleft: TExp, tcomp: TExp) -> TExp:
     @staticmethod
     def lte(tleft: TExp, tcomp: TExp) -> TExp:
         raise Exception("abstract")
+
+    # Operations
+
+    @staticmethod
+    def add(tleft: TExp, tcomp: TExp) -> TExp:
+        raise Exception("abstract")
diff --git a/test/test_qlassf_int.py b/test/test_qlassf_int.py
index 988f57aa..fa93701b 100644
--- a/test/test_qlassf_int.py
+++ b/test/test_qlassf_int.py
@@ -291,3 +291,15 @@ def test_composed_comparators(self):
     #     return a + 1
     # def test(a: Qint2, b: Qint2) -> Qint2:
     #     return a + b
+
+
+class TestQlassfIntAdd(unittest.TestCase):
+    def test_add(self):
+        f = "def test(a: Qint2, b: Qint2) -> Qint2: return a + b"
+        qf = qlassf(f, to_compile=COMPILATION_ENABLED)
+        compute_and_compare_results(self, qf)
+
+    def test_add_const(self):
+        f = "def test(a: Qint2) -> Qint2: return a + 1"
+        qf = qlassf(f, to_compile=COMPILATION_ENABLED)
+        compute_and_compare_results(self, qf)