"""
Billing Models for Credit System
"""
from django.db import models
from django.core.validators import MinValueValidator
from igny8_core.auth.models import AccountBaseModel


class CreditTransaction(AccountBaseModel):
    """Track all credit transactions (additions, deductions)"""
    TRANSACTION_TYPE_CHOICES = [
        ('purchase', 'Purchase'),
        ('subscription', 'Subscription Renewal'),
        ('refund', 'Refund'),
        ('deduction', 'Usage Deduction'),
        ('adjustment', 'Manual Adjustment'),
    ]
    
    transaction_type = models.CharField(max_length=20, choices=TRANSACTION_TYPE_CHOICES, db_index=True)
    amount = models.IntegerField(help_text="Positive for additions, negative for deductions")
    balance_after = models.IntegerField(help_text="Credit balance after this transaction")
    description = models.CharField(max_length=255)
    metadata = models.JSONField(default=dict, help_text="Additional context (AI call details, etc.)")
    created_at = models.DateTimeField(auto_now_add=True)
    
    class Meta:
        db_table = 'igny8_credit_transactions'
        ordering = ['-created_at']
        indexes = [
            models.Index(fields=['account', 'transaction_type']),
            models.Index(fields=['account', 'created_at']),
        ]
    
    def __str__(self):
        account = getattr(self, 'account', None)
        return f"{self.get_transaction_type_display()} - {self.amount} credits - {account.name if account else 'No Account'}"


class CreditUsageLog(AccountBaseModel):
    """Detailed log of credit usage per AI operation"""
    OPERATION_TYPE_CHOICES = [
        ('clustering', 'Keyword Clustering'),
        ('ideas', 'Content Ideas Generation'),
        ('content', 'Content Generation'),
        ('images', 'Image Generation'),
        ('reparse', 'Content Reparse'),
    ]
    
    operation_type = models.CharField(max_length=50, choices=OPERATION_TYPE_CHOICES, db_index=True)
    credits_used = models.IntegerField(validators=[MinValueValidator(0)])
    cost_usd = models.DecimalField(max_digits=10, decimal_places=4, null=True, blank=True)
    model_used = models.CharField(max_length=100, blank=True)
    tokens_input = models.IntegerField(null=True, blank=True, validators=[MinValueValidator(0)])
    tokens_output = models.IntegerField(null=True, blank=True, validators=[MinValueValidator(0)])
    related_object_type = models.CharField(max_length=50, blank=True)  # 'keyword', 'cluster', 'task'
    related_object_id = models.IntegerField(null=True, blank=True)
    metadata = models.JSONField(default=dict)
    created_at = models.DateTimeField(auto_now_add=True)
    
    class Meta:
        db_table = 'igny8_credit_usage_logs'
        ordering = ['-created_at']
        indexes = [
            models.Index(fields=['account', 'operation_type']),
            models.Index(fields=['account', 'created_at']),
            models.Index(fields=['account', 'operation_type', 'created_at']),
        ]
    
    def __str__(self):
        account = getattr(self, 'account', None)
        return f"{self.get_operation_type_display()} - {self.credits_used} credits - {account.name if account else 'No Account'}"