from django.db import models


class Unit(models.Model):

    class Meta:
        ordering = ('name',)

    name = models.CharField(max_length=100)
    abbreviation = models.CharField(max_length=10, blank=True, null=True)
    grams = models.DecimalField(max_digits=10, decimal_places=10,
            blank=True, null=True,
            help_text="Conversion from this unit to grams (dry measure)")
    liters = models.DecimalField(max_digits=10, decimal_places=10,
            blank=True, null=True,
            help_text="Conversion from this unit to liters (liquid measure)")

    def __unicode__(self):
        return "{0} ({1})".format(self.name, self.abbreviation)


class Recipe(models.Model):

    class Meta:
        ordering = ('title',)

    title = models.CharField(max_length=100)
    slug = models.SlugField(max_length=150)
    description = models.TextField(blank=True, null=True)
    servings = models.IntegerField(blank=True, null=True)
    instructions = models.TextField()
    oven_temp = models.IntegerField(blank=True, null=True)
    cook_time = models.IntegerField(blank=True, null=True, help_text="In minutes")
    prep_time = models.IntegerField(blank=True, null=True, help_text="In minutes")

    def __unicode__(self):
        return self.title


class Ingredient(models.Model):

    class Meta:
        ordering = ('name',)

    name = models.CharField(max_length=100, unique=True)

    def __unicode__(self):
        return self.name


class RecipeIngredient(models.Model):

    ingredient = models.ForeignKey(Ingredient)
    units = models.ForeignKey(Unit)
    quantity = models.FloatField()
    recipe = models.ForeignKey(Recipe)

    def __unicode__(self):
        return "{0} in {1}".format(self.ingredient.name, self.recipe.title)