initial commit of chapter 2 case study

python_3_oop/chapter02/menu.py

@@ -0,0 +1,69 @@
+import sys
+from notebook import Notebook, Note
+
+class Menu:
+    '''Display a menu and respond to choices when run.'''
+
+    def __init__(self):
+        self.notebook = Notebook()
+        self.choices = {
+            "1": self.show_notes,
+            "2": self.search_notes,
+            "3": self.add_note,
+            "4": self.modify_note,
+            "5": self.quit
+        }
+
+    def display_menu(self):
+        print("""
+Notebook Menu
+1. Show all Notes
+2. Search Notes
+3. Add Note
+4. Modify Note
+5. Quit """)
+
+    def run(self):
+        '''Display the menu and respond to choices.'''
+        while True:
+            self.display_menu()
+            choice = input("Enter an option: ")
+            action = self.choices.get(choice)
+            if action:
+                action()
+            else:
+                print("{0} is not a valid choice".format(choice))
+
+    def show_notes(self, notes=None):
+        if not notes:
+            notes = self.notebook.notes
+        for note in notes:
+            print("{0}: {1}\n{2}".format(note.id, note.tags, note.memo))
+
+    def search_notes(self):
+        filter = input("Search for: ")
+        notes = self.notebook.search(filter)
+        self.show_notes(notes)
+
+    def add_note(self):
+        memo = input("Enter a memo: ")
+        self.notebook.new_note(memo)
+        print("Your note has been added.")
+
+    def modify_note(self):
+        id = input("Enter a note id: ")
+        memo = input("Enter a memo: ")
+        tags = input("Enter tags: ")
+        if memo:
+            if not self.notebook.modify_memo(id, memo):
+                print("Note with id {0} doesn't exist.".format(id))
+        if tags:
+            if not self.notebook.modify_tags(id, tags):
+                print("Note with id {0} doesn't exist.".format(id))
+
+    def quit(self):
+        print("Thank you for using your notebook today.")
+        sys.exit(0)
+
+if __name__ == "__main__":
+    Menu().run()

python_3_oop/chapter02/notebook.py

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+import datetime
+
+# Store the next available id for all new notes
+last_id = 0
+
+class Note:
+    '''Represent a note in the notebook. Match against a
+    string in searches and store tags for each note.'''
+
+    def __init__(self, memo, tags=''):
+        '''initialize a note with memo and optional
+        space-separated tags. Automatically set the note's
+        creation date and a unique id.'''
+        self.memo = memo
+        self.tags = tags
+        self.creation_date = datetime.date.today()
+        global last_id
+        last_id += 1
+        self.id = last_id
+
+    def match(self, filter):
+        '''Determine if this note matches the filter
+        text. Return True if it matches, False otherwise.
+        Search is case sensitive and matches both text and
+        tags.'''
+        return filter in self.memo or filter in self.tags
+
+
+class Notebook:
+    '''Represent a collection of notes that can be tagged,
+    modified, and searched.'''
+
+    def __init__(self):
+        '''Initialize a notebook with an empty list.'''
+        self.notes = []
+
+    def new_note(self, memo, tags=''):
+        '''Create a new note and add it to the list.'''
+        self.notes.append(Note(memo, tags))
+
+    def modify_memo(self, note_id, memo):
+        '''Find the note with the given id and change its
+        memo to the given value.'''
+        note = self._find_note(note_id)
+        if note:
+            note.memo = memo
+            return True
+        return False
+
+    def modify_tags(self, note_id, tags):
+        '''Find the note with the given id and change its tags
+        to the given value.'''
+        note = self._find_note(note_id)
+        if note:
+            note.tags = tags
+            return True
+        return False
+
+    def search(self, filter):
+        '''Find all notes that match the given filter string.'''
+        return [note for note in self.notes if note.match(filter)]
+
+    def _find_note(self, note_id):
+        '''Locate the note with the given id.'''
+        for note in self.notes:
+            if str(note.id) == str(note_id):
+                return note
+        return None
+