[apps/graph/list] Define PlotTypeHelper

apps/graph/Makefile

@@ -21,6 +21,7 @@ app_graph_src = $(addprefix apps/graph/,\
   list/list_controller.cpp \
   list/list_parameter_controller.cpp \
   list/text_field_function_title_cell.cpp \
+  list/type_helper.cpp \
   values/derivative_parameter_controller.cpp \
   values/function_parameter_controller.cpp \
   values/values_controller.cpp \

apps/graph/list/type_helper.cpp

@@ -0,0 +1,37 @@
+#include "type_helper.h"
+#include <apps/i18n.h>
+#include <poincare/expression.h>
+#include <poincare/layout_helper.h>
+
+namespace Graph {
+
+namespace PlotTypeHelper {
+
+I18n::Message Message(int index) {
+  assert(0 <= index && index < NumberOfTypes);
+  static constexpr I18n::Message message[NumberOfTypes] = {
+    I18n::Message::Cartesian,
+    I18n::Message::Polar,
+    I18n::Message::Parametric
+  };
+  return message[index];
+}
+
+Poincare::Layout Layout(int index) {
+  assert(0 <= index && index < NumberOfTypes);
+  static constexpr const char * texts[NumberOfTypes] = {
+    "y=f(x)",
+    "r=f(θ)",
+    "[[x][y]]=f(t)"
+  };
+  const char * text = texts[index];
+  if (index < 2) {
+    return Poincare::LayoutHelper::String(text, strlen(text));
+  }
+  Poincare::Expression parametric = Poincare::Expression::Parse(text);
+  return parametric.createLayout(Poincare::Preferences::PrintFloatMode::Decimal, 1);
+}
+
+}
+
+}

apps/graph/list/type_helper.h

@@ -0,0 +1,19 @@
+#ifndef GRAPH_LIST_TYPE_HELPER_H
+#define GRAPH_LIST_TYPE_HELPER_H
+
+#include <escher/i18n.h>
+#include <poincare/layout.h>
+
+namespace Graph {
+
+namespace PlotTypeHelper {
+
+constexpr static int NumberOfTypes = 3;
+I18n::Message Message(int index);
+Poincare::Layout Layout(int index);
+
+}
+
+}
+
+#endif