From f3200fe2e96cad2d2d65f79c1f7a925948a7b5e7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=C3=A9a=20Saviot?= <lea.saviot@numworks.com>
Date: Tue, 17 Oct 2017 11:38:36 +0200
Subject: [PATCH] [code] Program store that uses an accordeon buffer to store
 the programs. The user can now add scripts. A contextual menu displays
 various options when clicking on a script, such as editing.

Change-Id: I124a17f7584b0beedb897e8499ca0a1bb6c13cbe
---
 apps/code/Makefile                         |   2 +
 apps/code/app.cpp                          |  13 +-
 apps/code/app.h                            |   6 +-
 apps/code/base.de.i18n                     |   5 +
 apps/code/base.en.i18n                     |   5 +
 apps/code/base.es.i18n                     |   5 +
 apps/code/base.fr.i18n                     |   5 +
 apps/code/base.pt.i18n                     |   5 +
 apps/code/editor_controller.cpp            |   8 +-
 apps/code/editor_controller.h              |   5 +-
 apps/code/menu_controller.cpp              |  72 ++++---
 apps/code/menu_controller.h                |  23 ++-
 apps/code/program.cpp                      |  43 +----
 apps/code/program.h                        |   7 +-
 apps/code/program_parameter_controller.cpp |  78 ++++++++
 apps/code/program_parameter_controller.h   |  43 +++++
 apps/code/program_store.cpp                | 208 +++++++++++++++++++++
 apps/code/program_store.h                  |  46 +++++
 escher/include/escher/text_area.h          |   5 +-
 escher/src/text_area.cpp                   |  22 ++-
 20 files changed, 513 insertions(+), 93 deletions(-)
 create mode 100644 apps/code/program_parameter_controller.cpp
 create mode 100644 apps/code/program_parameter_controller.h
 create mode 100644 apps/code/program_store.cpp
 create mode 100644 apps/code/program_store.h

diff --git a/apps/code/Makefile b/apps/code/Makefile
index f2d18db06..baa049a72 100644
--- a/apps/code/Makefile
+++ b/apps/code/Makefile
@@ -10,6 +10,8 @@ app_objs += $(addprefix apps/code/,\
   editor_controller.o\
   menu_controller.o\
   program.o\
+  program_parameter_controller.o\
+  program_store.o\
 )
 
 i18n_files += $(addprefix apps/code/,\
diff --git a/apps/code/app.cpp b/apps/code/app.cpp
index 63942a6ba..957aa68e8 100644
--- a/apps/code/app.cpp
+++ b/apps/code/app.cpp
@@ -17,9 +17,8 @@ const Image * App::Descriptor::icon() {
   return ImageStore::CodeIcon;
 }
 
-App::Snapshot::Snapshot() :
-  m_program()
-{
+App::Snapshot::Snapshot() {
+  m_programStore.addDefaultProgram();
 }
 
 App * App::Snapshot::unpack(Container * container) {
@@ -27,7 +26,7 @@ App * App::Snapshot::unpack(Container * container) {
 }
 
 void App::Snapshot::reset() {
-  m_program.setContent("");
+  m_programStore.deleteAll();
 }
 
 App::Descriptor * App::Snapshot::descriptor() {
@@ -35,14 +34,14 @@ App::Descriptor * App::Snapshot::descriptor() {
   return &descriptor;
 }
 
-Program * App::Snapshot::program() {
-  return &m_program;
+ProgramStore * App::Snapshot::programStore() {
+  return &m_programStore;
 }
 
 App::App(Container * container, Snapshot * snapshot) :
   ::App(container, snapshot, &m_codeStackViewController, I18n::Message::Warning),
   m_listFooter(&m_codeStackViewController, &m_menuController, &m_menuController, ButtonRowController::Position::Bottom, ButtonRowController::Style::EmbossedGrey),
-  m_menuController(&m_listFooter, snapshot->program(), &m_listFooter),
+  m_menuController(&m_listFooter, snapshot->programStore(), &m_listFooter),
   m_codeStackViewController(&m_modalViewController, &m_listFooter)
 {
 }
diff --git a/apps/code/app.h b/apps/code/app.h
index 5b300ba77..09638e397 100644
--- a/apps/code/app.h
+++ b/apps/code/app.h
@@ -3,7 +3,7 @@
 
 #include <escher.h>
 #include "menu_controller.h"
-#include "program.h"
+#include "program_store.h"
 #include "../shared/message_controller.h"
 
 namespace Code {
@@ -22,9 +22,9 @@ public:
     App * unpack(Container * container) override;
     void reset() override;
     Descriptor * descriptor() override;
-    Program * program();
+    ProgramStore * programStore();
   private:
-    Program m_program;
+    ProgramStore m_programStore;
   };
   StackViewController * stackViewController() { return &m_codeStackViewController; }
 private:
diff --git a/apps/code/base.de.i18n b/apps/code/base.de.i18n
index 12da69116..f61ece54d 100644
--- a/apps/code/base.de.i18n
+++ b/apps/code/base.de.i18n
@@ -1,4 +1,9 @@
 AddScript = "Add a script"
+ScriptOptions = "Script options"
+EditScript = "Edit script"
+RenameScript = "Rename script"
+AutoImportScript = "Auto import."
+DeleteScript = "Delete script"
 Console = "Console"
 ConsoleError = "Error"
 EditProgram = "Programm bearbeiten"
diff --git a/apps/code/base.en.i18n b/apps/code/base.en.i18n
index 20d5a5b76..0dfbd1d2f 100644
--- a/apps/code/base.en.i18n
+++ b/apps/code/base.en.i18n
@@ -1,4 +1,9 @@
 AddScript = "Add a script"
+ScriptOptions = "Script options"
+EditScript = "Edit script"
+RenameScript = "Rename script"
+AutoImportScript = "Auto import."
+DeleteScript = "Delete script"
 Console = "Console"
 ConsoleError = "Error"
 EditProgram = "Edit program"
diff --git a/apps/code/base.es.i18n b/apps/code/base.es.i18n
index e1e6419d5..98a2c6152 100644
--- a/apps/code/base.es.i18n
+++ b/apps/code/base.es.i18n
@@ -1,4 +1,9 @@
 AddScript = "Add a script"
+ScriptOptions = "Script options"
+EditScript = "Edit script"
+RenameScript = "Rename script"
+AutoImportScript = "Auto import."
+DeleteScript = "Delete script"
 Console = "Console"
 ConsoleError = "Error"
 EditProgram = "Editar el programa"
diff --git a/apps/code/base.fr.i18n b/apps/code/base.fr.i18n
index 2eadb6aeb..7088347f4 100644
--- a/apps/code/base.fr.i18n
+++ b/apps/code/base.fr.i18n
@@ -1,4 +1,9 @@
 AddScript = "Add a script"
+ScriptOptions = "Script options"
+EditScript = "Edit script"
+RenameScript = "Rename script"
+AutoImportScript = "Auto import."
+DeleteScript = "Delete script"
 Console = "Console"
 ConsoleError = "Error"
 EditProgram = "Editer le programme"
diff --git a/apps/code/base.pt.i18n b/apps/code/base.pt.i18n
index c10b49acd..1572add77 100644
--- a/apps/code/base.pt.i18n
+++ b/apps/code/base.pt.i18n
@@ -1,4 +1,9 @@
 AddScript = "Add a script"
+ScriptOptions = "Script options"
+EditScript = "Edit script"
+RenameScript = "Rename script"
+AutoImportScript = "Auto import."
+DeleteScript = "Delete script"
 Console = "Console"
 ConsoleError = "Error"
 EditProgram = "Editar programa"
diff --git a/apps/code/editor_controller.cpp b/apps/code/editor_controller.cpp
index 9a3f9f575..091adda0e 100644
--- a/apps/code/editor_controller.cpp
+++ b/apps/code/editor_controller.cpp
@@ -2,14 +2,14 @@
 
 namespace Code {
 
-EditorController::EditorController(Program * program) :
+EditorController::EditorController() :
   ViewController(nullptr),
-  m_view(this, program->editableContent(), program->bufferSize())
+  m_view(this)
 {
 }
 
-View * EditorController::view() {
-  return &m_view;
+void EditorController::setProgram(Program program){
+  m_view.setText(program.editableContent(), program.bufferSize());
 }
 
 bool EditorController::handleEvent(Ion::Events::Event event) {
diff --git a/apps/code/editor_controller.h b/apps/code/editor_controller.h
index 2b77faf2a..1b99805fa 100644
--- a/apps/code/editor_controller.h
+++ b/apps/code/editor_controller.h
@@ -8,8 +8,9 @@ namespace Code {
 
 class EditorController : public ViewController {
 public:
-  EditorController(Program * program);
-  View * view() override;
+  EditorController();
+  void setProgram(Program program);
+  View * view() override { return &m_view; }
   bool handleEvent(Ion::Events::Event event) override;
   void didBecomeFirstResponder() override;
 private:
diff --git a/apps/code/menu_controller.cpp b/apps/code/menu_controller.cpp
index 899a36a81..62a9acf72 100644
--- a/apps/code/menu_controller.cpp
+++ b/apps/code/menu_controller.cpp
@@ -4,19 +4,22 @@
 
 namespace Code {
 
-MenuController::MenuController(Responder * parentResponder, Program * program, ButtonRowController * footer) :
+MenuController::MenuController(Responder * parentResponder, ProgramStore * programStore, ButtonRowController * footer) :
   ViewController(parentResponder),
   ButtonRowDelegate(nullptr, footer),
+  m_programStore(programStore),
   m_addNewProgramCell(I18n::Message::AddScript),
-  m_editorController(program),
-  m_consoleController(parentResponder),
-  m_selectableTableView(this, this, 0, 1, Metric::CommonTopMargin, Metric::CommonRightMargin, Metric::CommonBottomMargin, Metric::CommonLeftMargin, this),
   m_consoleButton(this, I18n::Message::Console, Invocation([](void * context, void * sender) {
     MenuController * menu = (MenuController *)context;
     menu->app()->displayModalViewController(menu->consoleController(), 0.5f, 0.5f);
-  }, this))
+  }, this)),
+  m_selectableTableView(this, this, 0, 1, 0, 0, 0, 0, this, nullptr, false),
+  m_consoleController(parentResponder),
+  m_programParameterController(nullptr, I18n::Message::ScriptOptions, m_programStore)
 {
-  m_stackViewController = (StackViewController *) (parentResponder->parentResponder()); // TODO: Dirty?
+  for (int i = 0; i< k_maxNumberOfCells; i++) {
+    m_cells[i].setMessageFontSize(KDText::FontSize::Large);
+  }
 }
 
 ConsoleController * MenuController::consoleController() {
@@ -38,46 +41,65 @@ bool MenuController::handleEvent(Ion::Events::Event event) {
     footer()->setSelectedButton(0);
     return true;
   } else if (event == Ion::Events::Up) {
-    footer()->setSelectedButton(-1);
-    m_selectableTableView.selectCellAtLocation(0, numberOfRows()-1);
-    app()->setFirstResponder(&m_selectableTableView);
-    return true;
+    if (m_selectableTableView.selectedRow()<0) {
+      footer()->setSelectedButton(-1);
+      m_selectableTableView.selectCellAtLocation(0, numberOfRows()-1);
+      app()->setFirstResponder(&m_selectableTableView);
+      return true;
+    }
   }
-  ViewController * vc[2] = {&m_editorController, &m_consoleController};
   if (event == Ion::Events::OK || event == Ion::Events::EXE) {
-    app()->displayModalViewController(vc[selectedRow()], 0.5f, 0.5f);
-    return true;
+    int selectedRow = m_selectableTableView.selectedRow();
+    if (selectedRow >= 0 && selectedRow < m_programStore->numberOfPrograms()) {
+      configureProgram();
+      return true;
+    } else if (selectedRow == m_programStore->numberOfPrograms()) {
+      addProgram();
+      return true;
+    }
   }
   return false;
 }
 
+void MenuController::configureProgram() {
+  m_programParameterController.setProgram(m_selectableTableView.selectedRow());
+  stackViewController()->push(&m_programParameterController);
+}
+
+void MenuController::addProgram() {
+  m_selectableTableView.selectCellAtLocation(0, 0);
+  m_programStore->addDefaultProgram();
+  m_selectableTableView.reloadData();
+  m_selectableTableView.selectCellAtLocation(0, numberOfRows()-2);
+}
+
 int MenuController::numberOfRows() {
-  return k_totalNumberOfCells + 1;
+  return m_programStore->numberOfPrograms() + 1;
+  //TODO do not add the addProgram row if there can be no more programs stored.
 };
 
 KDCoordinate MenuController::cellHeight() {
-  return Metric::ParameterCellHeight;
+  return k_rowHeight;
 }
 
 HighlightCell * MenuController::reusableCell(int index) {
   assert(index >= 0);
-  if (index < k_totalNumberOfCells) {
+  if (index < m_programStore->numberOfPrograms()) {
     return &m_cells[index];
   }
-  assert(index == k_totalNumberOfCells);
+  assert(index == m_programStore->numberOfPrograms());
   return &m_addNewProgramCell;
 }
 
 int MenuController::reusableCellCount() {
-  return k_totalNumberOfCells + 1;
+  return m_programStore->numberOfPrograms() + 1;
 }
 
 void MenuController::willDisplayCellForIndex(HighlightCell * cell, int index) {
-  if (index < k_totalNumberOfCells) {
+  if (index < m_programStore->numberOfPrograms()) {
     MessageTableCell * myCell = (MessageTableCell *)cell;
-    I18n::Message titles[k_totalNumberOfCells] = {I18n::Message::EditProgram, I18n::Message::Console};
-    // TODO: translate Console in the .i18n
-    myCell->setMessage(titles[index]);
+    // TODO: store script names
+    myCell->setMessage(I18n::Message::Console);
   }
 }
 
@@ -87,7 +109,11 @@ int MenuController::numberOfButtons(ButtonRowController::Position position) cons
 
 Button * MenuController::buttonAtIndex(int index, ButtonRowController::Position position) const {
   assert(index == 0);
-  return (Button *) (&m_consoleButton);
+  return const_cast<Button *>(&m_consoleButton);
+}
+
+StackViewController * MenuController::stackViewController() {
+ return static_cast<StackViewController *>(parentResponder()->parentResponder());
 }
 
 }
diff --git a/apps/code/menu_controller.h b/apps/code/menu_controller.h
index c40f4e4e8..fa96374ad 100644
--- a/apps/code/menu_controller.h
+++ b/apps/code/menu_controller.h
@@ -3,17 +3,19 @@
 
 #include <escher.h>
 #include "console_controller.h"
-#include "editor_controller.h"
+#include "program_parameter_controller.h"
 #include <apps/shared/new_function_cell.h>
-#include "program.h"
+#include "program_store.h"
 
 namespace Code {
 
 class MenuController : public ViewController, public SimpleListViewDataSource, public SelectableTableViewDataSource, public ButtonRowDelegate {
 public:
-  MenuController(Responder * parentResponder, Program * program, ButtonRowController * footer);
+  MenuController(Responder * parentResponder, ProgramStore * programStore, ButtonRowController * footer);
   ConsoleController * consoleController();
-  StackViewController * stackViewController() { return m_stackViewController; }
+  StackViewController * stackViewController();
+  void configureProgram();
+  void addProgram();
 
   /* ViewController */
   View * view() override;
@@ -31,14 +33,15 @@ public:
   int numberOfButtons(ButtonRowController::Position position) const override;
   Button * buttonAtIndex(int index, ButtonRowController::Position position) const override;
 private:
-  constexpr static int k_totalNumberOfCells = 2;
-  MessageTableCell m_cells[k_totalNumberOfCells];
+  constexpr static int k_maxNumberOfCells = 5; //TODO
+  static constexpr KDCoordinate k_rowHeight = 50; //TODO create common parent class with Shared::ListController
+  ProgramStore * m_programStore;
+  MessageTableCell m_cells[k_maxNumberOfCells];
   Shared::NewFunctionCell m_addNewProgramCell;
-  StackViewController * m_stackViewController;
-  EditorController m_editorController;
-  ConsoleController m_consoleController;
-  SelectableTableView m_selectableTableView;
   Button m_consoleButton;
+  SelectableTableView m_selectableTableView;
+  ConsoleController m_consoleController;
+  ProgramParameterController m_programParameterController;
 };
 
 }
diff --git a/apps/code/program.cpp b/apps/code/program.cpp
index fd316ccd8..9fcb3c29c 100644
--- a/apps/code/program.cpp
+++ b/apps/code/program.cpp
@@ -2,52 +2,21 @@
 
 namespace Code {
 
-Program::Program() :
-  m_buffer()
+Program::Program(char * textBuffer, size_t sizeOfBuffer) :
+  m_bufferSize(sizeOfBuffer),
+  m_textBuffer(textBuffer)
 {
-  const char program[] = R"(# This program draws a Mandelbrot fractal set
-# N_iteration: degree of precision
-import kandinsky
-N_iteration = 10
-for x in range(320):
-  for y in range(240):
-# Compute the mandelbrot sequence for the point c = (c_r, c_i) with start value z = (z_r, z_i)
-    z_r = 0
-    z_i = 0
-# Rescale to fit the drawing screen 320x222
-    c_r = 2.7*x/319-2.1
-    c_i = -1.87*y/221+0.935
-    i = 0
-    while (i < N_iteration) and ((z_r * z_r) + (z_i * z_i) < 4):
-      i = i + 1
-      stock = z_r
-      z_r = z_r * z_r - z_i * z_i + c_r
-      z_i = 2 * stock * z_i + c_i
-# Choose the color of the dot from the Mandelbrot sequence
-    rgb = int(255*i/N_iteration)
-    col = kandinsky.color(int(rgb),int(rgb*0.75),int(rgb*0.25))
-# Draw a pixel colored in 'col' at position (x,y)
-    kandinsky.set_pixel(x,y,col))";
-
-  constexpr size_t len = sizeof(program);
-  static_assert(len < k_bufferSize, "Default program length bigger than buffer size");
-  memcpy(m_buffer, program, len);
 }
 
 const char * Program::readOnlyContent() const {
-  return m_buffer;
+  return m_textBuffer;
 }
 
 char * Program::editableContent() {
-  return m_buffer;
+  return m_textBuffer;
 }
-
-void Program::setContent(const char * program) {
-  memcpy(m_buffer, program, k_bufferSize);
-}
-
 int Program::bufferSize() const {
-  return k_bufferSize;
+  return m_bufferSize;
 }
 
 }
diff --git a/apps/code/program.h b/apps/code/program.h
index ea65782cb..7de37c75b 100644
--- a/apps/code/program.h
+++ b/apps/code/program.h
@@ -7,14 +7,13 @@ namespace Code {
 
 class Program {
 public:
-  Program();
+  Program(char * textBuffer, size_t sizeOfBuffer);
   const char * readOnlyContent() const;
   char * editableContent();
-  void setContent(const char * program);
   int bufferSize() const;
 private:
-  constexpr static int k_bufferSize = 1024;
-  char m_buffer[k_bufferSize];
+  size_t m_bufferSize;
+  char * m_textBuffer;
 };
 
 }
diff --git a/apps/code/program_parameter_controller.cpp b/apps/code/program_parameter_controller.cpp
new file mode 100644
index 000000000..27ed8060e
--- /dev/null
+++ b/apps/code/program_parameter_controller.cpp
@@ -0,0 +1,78 @@
+#include "program_parameter_controller.h"
+
+namespace Code {
+
+ProgramParameterController::ProgramParameterController(Responder * parentResponder, I18n::Message title, ProgramStore * programStore) :
+  ViewController(parentResponder),
+  m_pageTitle(title),
+  m_editProgram(I18n::Message::Default),
+  m_renameProgram(I18n::Message::Default),
+  m_autoImportProgram(I18n::Message::Default),
+  m_deleteProgram(I18n::Message::Default),
+  m_selectableTableView(this, this, 0, 1, Metric::CommonTopMargin, Metric::CommonRightMargin,
+    Metric::CommonBottomMargin, Metric::CommonLeftMargin, this),
+  m_programStore(programStore)
+{
+}
+
+void ProgramParameterController::setProgram(int i){
+  m_editorController.setProgram(m_programStore->editableProgram(i));
+}
+
+View * ProgramParameterController::view() {
+  return &m_selectableTableView;
+}
+
+const char * ProgramParameterController::title() {
+  return I18n::translate(m_pageTitle);
+}
+
+bool ProgramParameterController::handleEvent(Ion::Events::Event event) {
+  if (event == Ion::Events::OK || event == Ion::Events::EXE || (event == Ion::Events::Right && selectedRow() == 1)) {
+    switch (selectedRow()) {
+      case 0:
+        app()->displayModalViewController(&m_editorController, 0.5f, 0.5f);
+        return true;
+      //TODO other cases
+      default:
+        assert(false);
+        return false;
+    }
+  }
+  return false;
+}
+
+void ProgramParameterController::didBecomeFirstResponder() {
+ if (selectedRow() < 0) {
+    selectCellAtLocation(0, 0);
+  }
+  app()->setFirstResponder(&m_selectableTableView);
+}
+
+KDCoordinate ProgramParameterController::cellHeight() {
+  return Metric::ParameterCellHeight;
+}
+
+HighlightCell * ProgramParameterController::reusableCell(int index) {
+  assert(index >= 0);
+  assert(index < k_totalNumberOfCell);
+  HighlightCell * cells[] = {&m_editProgram, &m_renameProgram, &m_autoImportProgram, &m_deleteProgram};
+  return cells[index];
+
+}
+
+int ProgramParameterController::reusableCellCount() {
+  return k_totalNumberOfCell;
+}
+
+int ProgramParameterController::numberOfRows() {
+ return k_totalNumberOfCell;
+}
+
+void ProgramParameterController::willDisplayCellForIndex(HighlightCell * cell, int index) {
+  MessageTableCell * myCell = (MessageTableCell *)cell;
+  I18n::Message labels[k_totalNumberOfCell] = {I18n::Message::EditScript, I18n::Message::RenameScript, I18n::Message::AutoImportScript, I18n::Message::DeleteScript};
+  myCell->setMessage(labels[index]);
+}
+
+}
diff --git a/apps/code/program_parameter_controller.h b/apps/code/program_parameter_controller.h
new file mode 100644
index 000000000..ad3920949
--- /dev/null
+++ b/apps/code/program_parameter_controller.h
@@ -0,0 +1,43 @@
+#ifndef CODE_PROGRAM_PARAMETER_CONTROLLER_H
+#define CODE_PROGRAM_PARAMETER_CONTROLLER_H
+
+#include <escher.h>
+#include "../i18n.h"
+#include "editor_controller.h"
+#include "program_store.h"
+
+namespace Code {
+
+class ProgramParameterController : public ViewController, public SimpleListViewDataSource, public SelectableTableViewDataSource {
+public:
+  ProgramParameterController(Responder * parentResponder, I18n::Message title, ProgramStore * programStore);
+  void setProgram(int i);
+
+  /* ViewController */
+  View * view() override;
+  const char * title() override;
+  bool handleEvent(Ion::Events::Event event) override;
+  void didBecomeFirstResponder() override;
+
+  /* SimpleListViewDataSource */
+  KDCoordinate cellHeight() override;
+  HighlightCell * reusableCell(int index) override;
+  int reusableCellCount() override;
+  int numberOfRows() override;
+  void willDisplayCellForIndex(HighlightCell * cell, int index) override;
+
+private:
+  constexpr static int k_totalNumberOfCell = 4;
+  I18n::Message m_pageTitle;
+  MessageTableCell m_editProgram;
+  MessageTableCell m_renameProgram;
+  MessageTableCellWithSwitch m_autoImportProgram;
+  MessageTableCell m_deleteProgram;
+  SelectableTableView m_selectableTableView;
+  EditorController m_editorController;
+  ProgramStore * m_programStore;
+};
+
+}
+
+#endif
diff --git a/apps/code/program_store.cpp b/apps/code/program_store.cpp
new file mode 100644
index 000000000..f6c69af27
--- /dev/null
+++ b/apps/code/program_store.cpp
@@ -0,0 +1,208 @@
+#include "program_store.h"
+#include "string.h"
+#include <stddef.h>
+
+namespace Code {
+
+ProgramStore::ProgramStore() :
+  m_numberOfPrograms(0),
+  m_lastProgramEdited(-1)
+{
+  for (int i = 0; i<k_historySize; i ++) {
+    m_history[i] = FreeSpaceMarker;
+  }
+}
+
+Program ProgramStore::editableProgram(int i) {
+  assert(i >= 0 && i < numberOfPrograms());
+  cleanAndMoveFreeSpaceAfterProgram(i);
+  int beginningOfProgram = indexOfProgram(i);
+
+  // Compute the size of the program, including the free space of m_history
+  int sizeOfEditableProgram = 0;
+  for (int j=beginningOfProgram; j<k_historySize-1; j++) {
+    if (m_history[j] == FreeSpaceMarker && m_history[j+1] != FreeSpaceMarker) {
+      break;
+    }
+    sizeOfEditableProgram++;
+  }
+  m_lastProgramEdited = i;
+  return Program(&m_history[beginningOfProgram], sizeOfEditableProgram);
+}
+
+Program ProgramStore::program(int i) {
+  assert(i >= 0 && i < numberOfPrograms());
+  int beginningOfProgram = indexOfProgram(i);
+  return Program(&m_history[beginningOfProgram], strlen(&m_history[beginningOfProgram] + 1));
+}
+
+int ProgramStore::numberOfPrograms() const {
+  return m_numberOfPrograms;
+}
+
+Program ProgramStore::editableNewProgram() {
+  cleanAndMoveFreeSpaceAfterProgram(numberOfPrograms()-1);
+  m_numberOfPrograms++;
+  return Program(&m_history[indexOfFirstFreeSpaceMarker()], sizeOfFreeSpace() - 1);
+}
+
+void ProgramStore::deleteProgram(int i){
+  assert (i >= 0 && i < numberOfPrograms());
+  cleanAndMoveFreeSpaceAfterProgram(i);
+  int indexOfCharToDelete = indexOfProgram(i);
+  while (m_history[indexOfCharToDelete] != FreeSpaceMarker) {
+    m_history[indexOfCharToDelete] = FreeSpaceMarker;
+    indexOfCharToDelete++;
+  }
+  m_numberOfPrograms--;
+}
+
+void ProgramStore::deleteAll(){
+  for (int i = 0; i<numberOfPrograms(); i++){
+    deleteProgram(i);
+    //TODO moves the free space around, better to just put all the buffer to -1 ??
+  }
+  m_numberOfPrograms = 0;
+}
+
+int ProgramStore::indexOfProgram(int i) const {
+  assert (i >= 0 && i < numberOfPrograms());
+  int currentProgramNumber = 0;
+  int beginningOfProgram = 0;
+  while (m_history[beginningOfProgram] == FreeSpaceMarker) {
+    beginningOfProgram++;
+  }
+  if (i == 0) {
+    return beginningOfProgram;
+  }
+  for (int j=beginningOfProgram; j<k_historySize; j++) {
+    if (m_history[j] == 0) {
+      currentProgramNumber++;
+      if (currentProgramNumber == i) {
+        j++;
+        while (m_history[j] == FreeSpaceMarker) {
+          j++;
+        }
+        return j;
+      }
+    }
+  }
+  assert(false);
+  return 0;
+}
+
+int ProgramStore::lastIndexOfProgram(int i) const {
+  int indexOfPrgm = indexOfProgram(i);
+  int lastIndexOfProgram = indexOfPrgm + strlen(&m_history[indexOfPrgm]);
+  return lastIndexOfProgram;
+}
+
+int ProgramStore::indexOfFirstFreeSpaceMarker() const {
+  for (int i=0; i<k_historySize; i++) {
+    if (m_history[i] == FreeSpaceMarker) {
+      return i;
+    }
+  }
+  assert(false);
+  return 0;
+}
+
+int ProgramStore::sizeOfFreeSpace() const {
+  int sizeOfFreeSpace = 0;
+  for (int i=0; i<k_historySize; i++) {
+    if (m_history[i] == FreeSpaceMarker) {
+      sizeOfFreeSpace++;
+    } else {
+      if (sizeOfFreeSpace > 0) {
+        return sizeOfFreeSpace;
+      }
+    }
+  }
+  return sizeOfFreeSpace;
+}
+
+void ProgramStore::cleanFreeSpace() {
+  if (m_lastProgramEdited < 0 || m_lastProgramEdited >= numberOfPrograms()) {
+    return;
+  }
+  int indexOfCharToChangeIntoFreeSpaceMarker = lastIndexOfProgram(m_lastProgramEdited) + 1;
+  while (m_history[indexOfCharToChangeIntoFreeSpaceMarker] != FreeSpaceMarker) {
+    m_history[indexOfCharToChangeIntoFreeSpaceMarker] = FreeSpaceMarker;
+    indexOfCharToChangeIntoFreeSpaceMarker ++;
+  }
+}
+
+void ProgramStore::moveFreeSpaceAfterProgram(int i) {
+  m_lastProgramEdited = i;
+
+  // If the free space is already just after the program, return
+  int indexOfFreeSpace = indexOfFirstFreeSpaceMarker();
+  int lastIndexOfPrgm = lastIndexOfProgram(i);
+  if (indexOfFreeSpace == lastIndexOfPrgm + 1){
+    return;
+  }
+  // Else move the free space depending on its relative position with the program
+  int freeSpaceSize = sizeOfFreeSpace();
+  if (indexOfFreeSpace > lastIndexOfPrgm) {
+    int indexOfNextProgram = lastIndexOfPrgm+1;
+    int len = indexOfFreeSpace - indexOfNextProgram;
+    // Use memmove to avoid overwriting
+    memmove(&m_history[indexOfNextProgram + freeSpaceSize], &m_history[indexOfNextProgram], len);
+    for (int j = indexOfNextProgram; j<indexOfNextProgram+freeSpaceSize; j++) {
+      m_history[j] = FreeSpaceMarker;
+    }
+  } else {
+    int indexOfPrgm = indexOfProgram(i);
+    int len = lastIndexOfPrgm - (indexOfFreeSpace + freeSpaceSize) + 1;
+    // Use memcopy to avoid overwriting
+    memcpy(&m_history[indexOfFreeSpace], &m_history[indexOfPrgm], len);
+    for (int j = lastIndexOfPrgm - freeSpaceSize + 1 ; j<=lastIndexOfPrgm; j++) {
+      m_history[j] = FreeSpaceMarker;
+    }
+  }
+}
+
+void ProgramStore::cleanAndMoveFreeSpaceAfterProgram(int i) {
+  if (i >= 0 && i<numberOfPrograms()){
+    cleanFreeSpace();
+    moveFreeSpaceAfterProgram(i);
+  }
+}
+
+bool ProgramStore::addDefaultProgram() {
+  const char program[] = R"(# This program draws a Mandelbrot fractal set
+# N_iteration: degree of precision
+import kandinsky
+N_iteration = 10
+for x in range(320):
+  for y in range(240):
+# Compute the mandelbrot sequence for the point c = (c_r, c_i) with start value z = (z_r, z_i)
+    z_r = 0
+    z_i = 0
+# Rescale to fit the drawing screen 320x222
+    c_r = 2.7*x/319-2.1
+    c_i = -1.87*y/221+0.935
+    i = 0
+    while (i < N_iteration) and ((z_r * z_r) + (z_i * z_i) < 4):
+      i = i + 1
+      stock = z_r
+      z_r = z_r * z_r - z_i * z_i + c_r
+      z_i = 2 * stock * z_i + c_i
+# Choose the color of the dot from the Mandelbrot sequence
+    rgb = int(255*i/N_iteration)
+    col = kandinsky.color(int(rgb),int(rgb*0.75),int(rgb*0.25))
+# Draw a pixel colored in 'col' at position (x,y)
+    kandinsky.set_pixel(x,y,col))";
+
+  int len = strlen(program);
+  if (len + 1 > sizeOfFreeSpace() - 1) { // We keep at keast one free char.
+    return false;
+  }
+  cleanAndMoveFreeSpaceAfterProgram(numberOfPrograms()-1);
+  memcpy(&m_history[indexOfFirstFreeSpaceMarker()], program, len+1);
+  m_numberOfPrograms++;
+  m_lastProgramEdited = m_numberOfPrograms-1;
+  return true;
+}
+
+}
diff --git a/apps/code/program_store.h b/apps/code/program_store.h
new file mode 100644
index 000000000..72d4cb361
--- /dev/null
+++ b/apps/code/program_store.h
@@ -0,0 +1,46 @@
+#ifndef CODE_PROGRAM_STORE_H
+#define CODE_PROGRAM_STORE_H
+
+#include "program.h"
+
+namespace Code {
+
+class ProgramStore {
+public:
+  ProgramStore();
+  Program editableProgram(int i);
+  /* editableProgram moves the free space of m_history at the end of the
+   * ith script. It returns a Program object that points to the beginning of the
+   * wanted script and has a length taking into account both the script and the
+   * free space. */
+  Program program(int i);
+  /* programAtIndex returns a Program object that points to the beginning of the
+   * ith script and has the length of the script. */
+  int numberOfPrograms() const;
+  Program editableNewProgram();
+  bool addDefaultProgram();
+  void deleteProgram(int i);
+  void deleteAll();
+private:
+  static constexpr char FreeSpaceMarker = 0x01;
+  /* We made sure that 0x01 is not used in ion/include/ion/charset.h */
+  static constexpr int k_historySize = 1024;
+  int indexOfProgram(int i) const;
+  int lastIndexOfProgram(int i) const;
+  int indexOfFirstFreeSpaceMarker() const;
+  int sizeOfFreeSpace() const;
+  void cleanFreeSpace();
+  void moveFreeSpaceAfterProgram(int i);
+  void cleanAndMoveFreeSpaceAfterProgram(int i);
+  char m_history[k_historySize];
+  /* The m_history variable sequentially stores scripts as text buffers. The
+   * free bytes of m_history contain the FreeSpaceMarker. By construction,
+   * there is always at least one free byte, and the free space is always
+   * continuous. */
+  int m_numberOfPrograms;
+  int m_lastProgramEdited;
+};
+
+}
+
+#endif
diff --git a/escher/include/escher/text_area.h b/escher/include/escher/text_area.h
index 07f3a6101..c73fd9e39 100644
--- a/escher/include/escher/text_area.h
+++ b/escher/include/escher/text_area.h
@@ -9,17 +9,19 @@
 
 class TextArea : public ScrollableView, public ScrollViewDataSource {
 public:
-  TextArea(Responder * parentResponder, char * textBuffer, size_t textBufferSize,
+  TextArea(Responder * parentResponder, char * textBuffer = nullptr, size_t textBufferSize = 0,
     TextAreaDelegate * delegate = nullptr, KDText::FontSize fontSize = KDText::FontSize::Large,
     KDColor textColor = KDColorBlack, KDColor backgroundColor = KDColorWhite);
 
   void setDelegate(TextAreaDelegate * delegate);
   bool handleEvent(Ion::Events::Event event) override;
+  void setText(char * textBuffer, size_t textBufferSize);
 
 private:
   class Text {
   public:
     Text(char * buffer, size_t bufferSize);
+    void setText(char * buffer, size_t bufferSize);
 
     class Line {
     public:
@@ -84,6 +86,7 @@ private:
       KDColor textColor, KDColor backgroundColor);
     void drawRect(KDContext * ctx, KDRect rect) const override;
     KDSize minimalSizeForOptimalDisplay() const override;
+    void setText(char * textBuffer, size_t textBufferSize);
     void insertText(const char * text);
     void moveCursorIndex(int deltaX);
     void moveCursorGeo(int deltaX, int deltaY);
diff --git a/escher/src/text_area.cpp b/escher/src/text_area.cpp
index 7577b9249..f7673af0b 100644
--- a/escher/src/text_area.cpp
+++ b/escher/src/text_area.cpp
@@ -1,6 +1,5 @@
 #include <escher/text_area.h>
 #include <escher/clipboard.h>
-#include <assert.h>
 
 #include <stddef.h>
 #include <assert.h>
@@ -15,7 +14,11 @@ TextArea::Text::Text(char * buffer, size_t bufferSize) :
   m_buffer(buffer),
   m_bufferSize(bufferSize)
 {
-  assert(m_buffer != nullptr);
+}
+
+void TextArea::Text::setText(char * buffer, size_t bufferSize) {
+  m_buffer = buffer;
+  m_bufferSize = bufferSize;
 }
 
 TextArea::Text::Line::Line(const char * text) :
@@ -41,6 +44,7 @@ TextArea::Text::LineIterator & TextArea::Text::LineIterator::operator++() {
 }
 
 size_t TextArea::Text::indexAtPosition(Position p) {
+  assert(m_buffer != nullptr);
   if (p.line() < 0) {
     return 0;
   }
@@ -60,6 +64,7 @@ size_t TextArea::Text::indexAtPosition(Position p) {
 }
 
 TextArea::Text::Position TextArea::Text::positionAtIndex(size_t index) {
+  assert(m_buffer != nullptr);
   assert(index < m_bufferSize);
   const char * target = m_buffer + index;
   size_t y = 0;
@@ -75,6 +80,7 @@ TextArea::Text::Position TextArea::Text::positionAtIndex(size_t index) {
 }
 
 void TextArea::Text::insertChar(char c, size_t index) {
+  assert(m_buffer != nullptr);
   assert(index < m_bufferSize-1);
   char previous = c;
   for (size_t i=index; i<m_bufferSize; i++) {
@@ -88,6 +94,7 @@ void TextArea::Text::insertChar(char c, size_t index) {
 }
 
 char TextArea::Text::removeChar(size_t index) {
+  assert(m_buffer != nullptr);
   assert(index < m_bufferSize-1);
   char deletedChar = m_buffer[index];
   for (size_t i=index; i<m_bufferSize; i++) {
@@ -100,6 +107,7 @@ char TextArea::Text::removeChar(size_t index) {
 }
 
 int TextArea::Text::removeRemainingLine(size_t index, int direction) {
+  assert(m_buffer != nullptr);
   assert(index >= 0 && index < m_bufferSize);
   int jump = index;
   while (m_buffer[jump] != '\n' && m_buffer[jump] != 0 && jump >= 0) {
@@ -127,6 +135,7 @@ int TextArea::Text::removeRemainingLine(size_t index, int direction) {
 }
 
 TextArea::Text::Position TextArea::Text::span() const {
+  assert(m_buffer != nullptr);
   size_t width = 0;
   size_t height = 0;
   for (Line l : *this) {
@@ -209,6 +218,11 @@ void TextArea::ContentView::layoutSubviews() {
   m_cursorView.setFrame(cursorRect());
 }
 
+void TextArea::TextArea::ContentView::setText(char * textBuffer, size_t textBufferSize) {
+  m_text.setText(textBuffer, textBufferSize);
+  m_cursorIndex = 0;
+}
+
 void TextArea::TextArea::ContentView::insertText(const char * text) {
   int textSize = strlen(text);
   if (m_text.textLength() + textSize >= m_text.bufferSize() || textSize == 0) {
@@ -307,6 +321,10 @@ TextArea::TextArea(Responder * parentResponder, char * textBuffer,
   assert(textBufferSize < INT_MAX/2);
 }
 
+void TextArea::setText(char * textBuffer, size_t textBufferSize) {
+  m_contentView.setText(textBuffer, textBufferSize);
+}
+
 bool TextArea::TextArea::handleEvent(Ion::Events::Event event) {
   if (event == Ion::Events::Left) {
     m_contentView.moveCursorIndex(-1);