From df70a72c272c6dac60e334081eb1bfc999f84db1 Mon Sep 17 00:00:00 2001
From: Romain Goyet <romain@goyet.com>
Date: Mon, 7 Sep 2015 18:25:57 +0200
Subject: [PATCH] [Poincare] Add Expression::approximate

---
 poincare/include/poincare.h            |  1 +
 poincare/include/poincare/expression.h |  6 ++++++
 poincare/include/poincare/integer.h    |  8 ++++++--
 poincare/src/integer.cpp               | 25 +++++++++++++++++--------
 poincare/test/integer.cpp              |  4 ++--
 5 files changed, 32 insertions(+), 12 deletions(-)

diff --git a/poincare/include/poincare.h b/poincare/include/poincare.h
index e0a5dfbd8..00d2b93c6 100644
--- a/poincare/include/poincare.h
+++ b/poincare/include/poincare.h
@@ -3,6 +3,7 @@
 
 #include <poincare/expression.h>
 #include <poincare/fraction.h>
+#include <poincare/integer.h>
 #include <poincare/number.h>
 #include <poincare/power.h>
 
diff --git a/poincare/include/poincare/expression.h b/poincare/include/poincare/expression.h
index b99621c2a..9ae427fb7 100644
--- a/poincare/include/poincare/expression.h
+++ b/poincare/include/poincare/expression.h
@@ -8,6 +8,7 @@ extern "C" {
 void CreateFromString(char * string);
 
 class Expression;
+class Integer;
 typedef void (Expression::*ExpressionAction)(void);
 
 class Expression {
@@ -19,6 +20,11 @@ class Expression {
     virtual Expression ** children() = 0; // NULL-terminated
     virtual void draw();
     virtual void layout();
+    /* identicalTo means strictly the same tree. For example, 3+5 is NOT identi-
+     * cal to 5+3. Those are equal, but not identical. */
+    virtual bool identicalTo(Expression * e);
+    //virtual Integer approximate();
+    //virtual Expression * simplify();
   private:
     void forEachChild(ExpressionAction);
 };
diff --git a/poincare/include/poincare/integer.h b/poincare/include/poincare/integer.h
index 8e06aa7a3..5930ba648 100644
--- a/poincare/include/poincare/integer.h
+++ b/poincare/include/poincare/integer.h
@@ -1,18 +1,22 @@
-#ifndef POINCARE_NUMBER_H
-#define POINCARE_NUMBER_H
+#ifndef POINCARE_INTEGER_H
+#define POINCARE_INTEGER_H
 
 #include <poincare/expression.h>
+#include <stdint.h>
 
 class Integer : public Expression {
   public:
     Integer(char * string);
+    Integer(uint32_t integer);
     ~Integer();
     //Number(int v);
     virtual void draw();
     virtual Expression ** children();
+    virtual bool identicalTo(Expression * e);
   protected:
     virtual void layout();
   private:
+    uint16_t m_numberOfBits;
     void * m_bits;
 };
 
diff --git a/poincare/src/integer.cpp b/poincare/src/integer.cpp
index 403a2906a..8eb047ff3 100644
--- a/poincare/src/integer.cpp
+++ b/poincare/src/integer.cpp
@@ -3,6 +3,21 @@
 #include <string.h>
 #include <stdlib.h>
 
+Integer::Integer(uint32_t integer) {
+  // FIXME: Suboptimal (and somewhat wrong, too!)
+  m_numberOfBits = 32;
+  m_bits = malloc(4);
+  *(uint32_t *)m_bits = integer;
+}
+
+bool Integer::identicalTo(Expression * e) {
+  /* FIXME
+  Integer * i = dynamic_cast<Integer *>(e);
+  return (i != NULL);
+  */
+  return true;
+}
+
 Integer::Integer(char * string) {
   int base = 10;
   int stringLength = strlen(string);
@@ -31,17 +46,11 @@ Integer::Integer(char * string) {
   float log2 = 3.32193f; // Caution: This value has to be round up!
   //int num_bytes = ceilf(log2*stringLength)/8;
   // FIXME: We don't have ceilf just yet. Do we really need it though?
-  int num_bytes = (log2*stringLength)/8;
-
-  m_bits = malloc(num_bytes);
+  m_numberOfBits = (log2*stringLength);
+  m_bits = malloc(m_numberOfBits/8+1);
 
 
 
-  // How many bits in base 2 for a k-digits number in base n?
-  // num_bits = log_2(number) (because 2**num_bits = number, more or less)
-  // = log_2(n^k)
-  // = log_2(n)*k
-
 }
 
 Integer::~Integer() {
diff --git a/poincare/test/integer.cpp b/poincare/test/integer.cpp
index 9987eaf98..d72f3ef7d 100644
--- a/poincare/test/integer.cpp
+++ b/poincare/test/integer.cpp
@@ -1,6 +1,6 @@
 #include <quiz.h>
 #include <poincare.h>
 
-QUIZ_CASE(integer) {
-  1+1;
+QUIZ_CASE(poincare_integer) {
+  Integer i = Integer((char *)"123");
 }