from __future__ import with_statement

import web
from web import form
from web.form import Validator

from model import *
from helper import appdir
from renderer import render

import datetime, decimal
import operator as op
from sqlalchemy import sql

class Show:
    def GET(self, year = '', month = ''):
        if year:
            c = self.calc(year, month)
            return self.render([c], self.is_last(c))
        else:
            d = datetime.date.today()
            
            first = self.calc(d.year, d.month)
            if d.month == 1:
                second = self.calc(d.year - 1, 12)
            else:
                second = self.calc(d.year, d.month - 1)

            return self.render([first, second], self.is_last(first))

    def calc(self, year, month):

        year = int(year)
        month = int(month)

        ssum = sql.functions.sum(SingleExpense.expense)
        query = SingleExpense.of_month(month, year)

        result = query.group_by(SingleExpense.category_id).\
                 values(SingleExpense.category_id, ssum)

        exps = [CatExpense(Category.query.get(c), s, query.filter(SingleExpense.category_id == c)) for c,s in result]

        return MonthExpense(datetime.date(int(year), int(month), 1), exps)

    def is_last(self, exp):
        return exp.date >= datetime.date.today().replace(day = 1)

    def render(self, exps, is_last):
        return render("show", exps = exps, is_last = is_last)

class Add:

    dformat = "%d.%m.%Y"
    template = "add"

    def GET(self):
        return render(self.template, form = self.form())

    def POST(self):
        f = self.form()
        if f.validates():
            category = Category.get_by(name = f.category.value)
            
            e = self.get_expense()
            e.category = category
            e.date = datetime.datetime.strptime(f.date.value, self.dformat)
            e.expense = decimal.Decimal(f.expense.value)
            e.description = f.description.value

            raise web.seeother("/")
        else:
            return render(self.template, form = f)

    def get_expense(self):
        return SingleExpense()

    def form(self):
        return form.Form(
                form.Textbox(
                    "date",
                    form.notnull,
                    Validator("Date Format does not match", lambda v: datetime.datetime.strptime(v, self.dformat)),
                    value = datetime.date.today().strftime(self.dformat)
                    ),
                form.Textbox(
                    "expense",
                    form.notnull,
                    Validator("Not a valid decimal", decimal.Decimal),
                    ),
                form.Textbox(
                    "description",
                    form.notnull
                    ),
                form.Dropdown(
                    "category",
                    map(op.itemgetter(0), sorted(Category.query.values(Category.name)))
                    )
                )

class Edit (Add):

    template = "edit"

    def GET(self, id):
        exp = SingleExpense.get(id)
        self.get_expense = lambda *x: exp
        
        fvalues = { "date" : exp.date.strftime(self.dformat), "expense" : str(exp.expense), "description" : exp.description, "category" : exp.category.name }
        f = self.form()
        f.fill(fvalues)

        return render(self.template, form = f)

    def POST(self, id):
        exp = SingleExpense.get(id)
        self.get_expense = lambda *x: exp
        return Add.POST(self)

class Const:
    def GET(self):
        return "Const"

class ConstAdd:
    template = "constadd"
    dformat = "%m.%Y"

    def GET(self):
        return render(self.template, form = self.form())

    def POST(self):
        f = self.form()
        if f.validates():
            category = Category.get_by(name = f.category.value)
            
            e = self.get_expense()
            e.category = category
            e.start = datetime.datetime.strptime(f.start.value, self.dformat)
            e.end = datetime.datetime.strptime(f.end.value, self.dformat)
            e.months = f.months.value
            e.expense = decimal.Decimal(f.expense.value)
            e.description = f.description.value

            raise web.seeother("/")
        else:
            return render(self.template, form = f)

    def get_expense(self):
        return ConstExpense()

    def form(self):
        return form.Form(
                form.Textbox(
                    "start",
                    form.notnull,
                    Validator("Date Format does not match", lambda v: datetime.datetime.strptime(v, self.dformat)),
                    value = datetime.date.today().strftime(self.dformat)
                    ),
                form.Textbox(
                    "end",
                    form.notnull,
                    Validator("Date Format does not match", lambda v: datetime.datetime.strptime(v, self.dformat)),
                    value = datetime.date.today().strftime(self.dformat)
                    ),
                form.Textbox(
                    "months",
                    form.notnull,
                    Validator("Not an integer > 0", lambda v: int(v) > 0),
                    value = "12",
                    description = "Number of Months"
                    ),
                form.Textbox(
                    "expense",
                    form.notnull,
                    Validator("Not a valid decimal", decimal.Decimal),
                    ),
                form.Textbox(
                    "description",
                    form.notnull
                    ),
                form.Dropdown(
                    "category",
                    map(op.itemgetter(0), sorted(Category.query.values(Category.name)))
                    )
                )

class ConstEdit (ConstAdd):
    template = "constedit"
    
    def GET(self, id):
        exp = ConstExpense.get(id)
        self.get_expense = lambda *x: exp
        
        fvalues = {
                "start" : exp.start.strftime(self.dformat),
                "end" : exp.end.strftime(self.dformat),
                "months" : str(exp.months),
                "expense" : str(exp.expense),
                "description" : exp.description,
                "category" : exp.category.name
                }
        f = self.form()
        f.fill(fvalues)

        return render(self.template, form = f)

    def POST(self, id):
        exp = ConstExpense.get(id)
        self.get_expense = lambda *x: exp
        return ConstAdd.POST(self)

class Cat:
    def GET(self):
        categories = Category.query.order_by(Category.name).all()

        return render("cats", cats = categories)

    def POST(self):
        for id, name in web.input().iteritems():
            if id.startswith("n-"):
                Category(name = name)
            else:
                Category.get(id).name = name

        raise web.seeother("/")

class FourOhFour:
    """
    404 error page.
    """

    def GET (self, p):
        raise self.catch(p)

    @staticmethod
    def catch (page = "?"):
        return web.notfound(render("404", level = "", page = page))