#!/usr/bin/env python

# -*- coding: utf-8 -*-

"""

*TL;DR80

Separates data in GUIs from the ways it is presented, and accepted.

"""

class Model(object):

    def __iter__(self):

        raise NotImplementedError

    def get(self, item):

        """Returns an object with a .items() call method

        that iterates over key,value pairs of its information."""

        raise NotImplementedError

    @property

    def item_type(self):

        raise NotImplementedError

class ProductModel(Model):

    class Price(float):

        """A polymorphic way to pass a float with a particular

        __str__ functionality."""

        def __str__(self):

            first_digits_str = str(round(self, 2))

            try:

                dot_location = first_digits_str.index('.')

            except ValueError:

                return (first_digits_str + '.00')

            else:

                return (first_digits_str +

                        '0' * (3 + dot_location - len(first_digits_str)))

    products = {

        'milk': {'price': Price(1.50), 'quantity': 10},

        'eggs': {'price': Price(0.20), 'quantity': 100},

        'cheese': {'price': Price(2.00), 'quantity': 10}

    }

    item_type = 'product'

    def __iter__(self):

        for item in self.products:

            yield item

    def get(self, product):

        try:

            return self.products[product]

        except KeyError as e:

            raise KeyError((str(e) + " not in the model's item list."))

class View(object):

    def show_item_list(self, item_type, item_list):

        raise NotImplementedError

    def show_item_information(self, item_type, item_name, item_info):

        """Will look for item information by iterating over key,value pairs

        yielded by item_info.items()"""

        raise NotImplementedError

    def item_not_found(self, item_type, item_name):

        raise NotImplementedError

class ConsoleView(View):

    def show_item_list(self, item_type, item_list):

        print(item_type.upper() + ' LIST:')

        for item in item_list:

            print(item)

        print('')

    @staticmethod

    def capitalizer(string):

        return string[0].upper() + string[1:].lower()

    def show_item_information(self, item_type, item_name, item_info):

        print(item_type.upper() + ' INFORMATION:')

        printout = 'Name: %s' % item_name

        for key, value in item_info.items():

            printout += (', ' + self.capitalizer(str(key)) + ': ' + str(value))

        printout += '\n'

        print(printout)

    def item_not_found(self, item_type, item_name):

        print('That %s "%s" does not exist in the records' %

              (item_type, item_name))

class Controller(object):

    def __init__(self, model, view):

        self.model = model

        self.view = view

    def show_items(self):

        items = list(self.model)

        item_type = self.model.item_type

        self.view.show_item_list(item_type, items)

    def show_item_information(self, item_name):

        try:

            item_info = self.model.get(item_name)

        except:

            item_type = self.model.item_type

            self.view.item_not_found(item_type, item_name)

        else:

            item_type = self.model.item_type

            self.view.show_item_information(item_type, item_name, item_info)

if __name__ == '__main__':

    model = ProductModel()

    view = ConsoleView()

    controller = Controller(model, view)

    controller.show_items()

    controller.show_item_information('cheese')

    controller.show_item_information('eggs')

    controller.show_item_information('milk')

    controller.show_item_information('arepas')

### OUTPUT ###

# PRODUCT LIST:

# cheese

# eggs

# milk

#

# PRODUCT INFORMATION:

# Name: Cheese, Price: 2.00, Quantity: 10

#

# PRODUCT INFORMATION:

# Name: Eggs, Price: 0.20, Quantity: 100

#

# PRODUCT INFORMATION:

# Name: Milk, Price: 1.50, Quantity: 10

#

# That product "arepas" does not exist in the records