from django.conf import settings
from django.db import models

from infrasynth.shared.enums import BillingInterval, InvoiceStatus, SubscriptionStatus


class PaymentGateway(models.Model):
    slug = models.SlugField(max_length=100, primary_key=True)
    display_name = models.CharField(max_length=200)
    gateway_class = models.CharField(max_length=500)
    config = models.JSONField(default=dict)
    is_active = models.BooleanField(default=True)
    supported_currencies = models.JSONField(default=list)
    webhook_secret = models.CharField(max_length=500, blank=True)

    class Meta:
        db_table = "billing_gateway"

    def __str__(self):
        return self.display_name


class BillingPlan(models.Model):
    slug = models.SlugField(max_length=100, unique=True)
    name = models.CharField(max_length=200)
    description = models.TextField(blank=True)
    price_amount = models.DecimalField(max_digits=12, decimal_places=2)
    price_currency = models.CharField(max_length=3, default="USD")
    interval = models.CharField(max_length=20, choices=BillingInterval.choices)
    trial_days = models.IntegerField(default=0)
    features = models.JSONField(default=list)
    is_active = models.BooleanField(default=True)
    gateway = models.ForeignKey(
        PaymentGateway,
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name="+",
    )
    external_id = models.CharField(max_length=255, blank=True)

    class Meta:
        db_table = "billing_plan"

    def __str__(self):
        return self.name


class Subscription(models.Model):
    user = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        on_delete=models.CASCADE,
        related_name="+",
    )
    plan = models.ForeignKey(
        BillingPlan,
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name="+",
    )
    gateway = models.ForeignKey(
        PaymentGateway,
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name="+",
    )
    external_id = models.CharField(max_length=255, blank=True)
    status = models.CharField(max_length=20, choices=SubscriptionStatus.choices)
    current_period_start = models.DateTimeField(null=True, blank=True)
    current_period_end = models.DateTimeField(null=True, blank=True)
    cancel_at_period_end = models.BooleanField(default=False)
    cancelled_at = models.DateTimeField(null=True, blank=True)
    trial_end = models.DateTimeField(null=True, blank=True)
    metadata = models.JSONField(default=dict)

    class Meta:
        db_table = "billing_subscription"

    def __str__(self):
        return f"{self.user}#{self.plan}"


class Invoice(models.Model):
    subscription = models.ForeignKey(
        Subscription,
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name="+",
    )
    user = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        on_delete=models.CASCADE,
        related_name="+",
    )
    gateway = models.ForeignKey(
        PaymentGateway,
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name="+",
    )
    external_id = models.CharField(max_length=255, blank=True)
    invoice_number = models.CharField(max_length=100, unique=True)
    amount = models.DecimalField(max_digits=12, decimal_places=2)
    currency = models.CharField(max_length=3, default="USD")
    tax_amount = models.DecimalField(max_digits=12, decimal_places=2, default=0)
    tax_name = models.CharField(max_length=100, blank=True)
    status = models.CharField(max_length=20, choices=InvoiceStatus.choices)
    due_date = models.DateTimeField(null=True, blank=True)
    paid_at = models.DateTimeField(null=True, blank=True)
    line_items = models.JSONField(default=list)
    pdf_file = models.ForeignKey(
        "infrasynth_files.StoredFile",
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name="+",
    )
    metadata = models.JSONField(default=dict)

    class Meta:
        db_table = "billing_invoice"

    def __str__(self):
        return self.invoice_number


class PaymentTransaction(models.Model):
    invoice = models.ForeignKey(
        Invoice,
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name="+",
    )
    gateway = models.ForeignKey(
        PaymentGateway,
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name="+",
    )
    external_id = models.CharField(max_length=255, blank=True)
    amount = models.DecimalField(max_digits=12, decimal_places=2)
    currency = models.CharField(max_length=3, default="USD")
    status = models.CharField(max_length=50, blank=True)
    payment_method = models.CharField(max_length=100, blank=True)
    metadata = models.JSONField(default=dict)
    created_at = models.DateTimeField(auto_now_add=True)

    class Meta:
        db_table = "billing_transaction"

    def __str__(self):
        return f"txn_{self.pk}"