from django.utils.translation import gettext_lazy as _
from django.db import models
from django.utils import timezone
from datetime import timedelta
from userapp.models import ParadiseUser


class SubscriptionPlan(models.Model):
    """订阅计划"""
    PLAN_CHOICES = (
        ('monthly', 'Monthly'),
        ('quarterly', 'Quarterly'),
        ('yearly', 'Yearly'),
    )
    name = models.CharField(_('name'), max_length=100)
    price = models.DecimalField(_('price'), max_digits=10, decimal_places=2)
    duration = models.CharField(_('duration'), max_length=10, choices=PLAN_CHOICES)

    def __str__(self):
        return f"{self.name} ({self.get_duration_display()})"
    class Meta:
        verbose_name = _('SubscriptionPlan')
        verbose_name_plural = _('SubscriptionPlan')

class Subscription(models.Model):
    """租户订阅"""
    user = models.ForeignKey(ParadiseUser, default=0, on_delete=models.CASCADE, verbose_name=_('user'))
    plan = models.ForeignKey(SubscriptionPlan, on_delete=models.CASCADE, verbose_name=_('plan'))
    start_date = models.DateTimeField(_('start_date'), default=timezone.now)
    end_date = models.DateTimeField(_('end_date'))
    last_billed = models.DateTimeField(_('last_billed'), null=True, blank=True)  # 上次账单生成日期

    def save(self, *args, **kwargs):
        if not self.end_date:
            if self.plan.duration == 'monthly':
                self.end_date = self.start_date + timedelta(days=30)
            elif self.plan.duration == 'quarterly':
                self.end_date = self.start_date + timedelta(days=90)
            elif self.plan.duration == 'yearly':
                self.end_date = self.start_date + timedelta(days=365)
        super().save(*args, **kwargs)

    def __str__(self):
        return f"Subscription for {self.tenant} ({self.plan.name})"
    class Meta:
        verbose_name = _('User Subscription')
        verbose_name_plural = _('User Subscription')


class AddOnPackage(models.Model):
    """加油包"""
    name = models.CharField(_('name'), max_length=100)
    description = models.TextField(_('description'))
    price = models.DecimalField(_('price'), max_digits=10, decimal_places=2)
    class Meta:
        verbose_name = _('AddOnPackage')
        verbose_name_plural = _('AddOnPackage')

class SubscriptionAddOn(models.Model):
    """租户订阅加油包"""
    subscription = models.ForeignKey(Subscription, on_delete=models.CASCADE, verbose_name=_('subscription'))
    add_on = models.ForeignKey(AddOnPackage, on_delete=models.CASCADE, verbose_name=_('add_on'))
    quantity = models.PositiveIntegerField(_('quantity'), default=1)
    added_on = models.DateTimeField(_('added_on'), auto_now_add=True)

    def total_price(self):
        return self.add_on.price * self.quantity
    
    def __str__(self):
        return f"{self.add_on.name} for {self.subscription.tenant}"
    class Meta:
        verbose_name = _('TenantSubscriptionAddOn')
        verbose_name_plural = _('TenantSubscriptionAddOn')

class TenantBilling(models.Model):
    """租户账单"""
    user = models.ForeignKey(ParadiseUser, default=0, on_delete=models.CASCADE, verbose_name=_('user'))
    subscription = models.ForeignKey(Subscription, on_delete=models.CASCADE, verbose_name=_('subscription'))
    total_price = models.DecimalField(_('total_price'), max_digits=10, decimal_places=2, default=0)
    billing_date = models.DateTimeField(_('billing_date'), auto_now_add=True)

    def calculate_total_price(self):
        # 基础订阅费用
        subscription_price = self.subscription.plan.price
        
        # 加油包费用
        add_on_price = sum([addon.total_price() for addon in self.subscription.subscriptionaddon_set.all()])
        
        self.total_price = subscription_price + add_on_price
        self.save()
    class Meta:
        verbose_name = _('TenantBilling')
        verbose_name_plural = _('TenantBilling')