credits adn tokens final correct setup

backend/igny8_core/business/billing/models.py

@@ -109,8 +109,8 @@ class CreditUsageLog(AccountBaseModel):
 
 class CreditCostConfig(models.Model):
     """
-    Configurable credit costs per AI function
-    Admin-editable alternative to hardcoded constants
+    Token-based credit pricing configuration.
+    ALL operations use token-to-credit conversion.
     """
     # Operation identification
     operation_type = models.CharField(
@@ -120,26 +120,27 @@ class CreditCostConfig(models.Model):
         help_text="AI operation type"
     )
     
-    # Cost configuration
-    credits_cost = models.IntegerField(
-        validators=[MinValueValidator(0)],
-        help_text="Credits required for this operation"
+    # Token-to-credit ratio (tokens per 1 credit)
+    tokens_per_credit = models.IntegerField(
+        default=100,
+        validators=[MinValueValidator(1)],
+        help_text="Number of tokens that equal 1 credit (e.g., 100 tokens = 1 credit)"
     )
     
-    # Unit of measurement
-    UNIT_CHOICES = [
-        ('per_request', 'Per Request'),
-        ('per_100_words', 'Per 100 Words'),
-        ('per_200_words', 'Per 200 Words'),
-        ('per_item', 'Per Item'),
-        ('per_image', 'Per Image'),
-    ]
+    # Minimum credits (for very small token usage)
+    min_credits = models.IntegerField(
+        default=1,
+        validators=[MinValueValidator(0)],
+        help_text="Minimum credits to charge regardless of token usage"
+    )
     
-    unit = models.CharField(
-        max_length=50,
-        default='per_request',
-        choices=UNIT_CHOICES,
-        help_text="What the cost applies to"
+    # Price per credit (for revenue reporting)
+    price_per_credit_usd = models.DecimalField(
+        max_digits=10,
+        decimal_places=4,
+        default=Decimal('0.01'),
+        validators=[MinValueValidator(Decimal('0.0001'))],
+        help_text="USD price per credit (for revenue reporting)"
     )
     
     # Metadata
@@ -149,6 +150,7 @@ class CreditCostConfig(models.Model):
     # Status
     is_active = models.BooleanField(default=True, help_text="Enable/disable this operation")
     
+    
     # Audit fields
     created_at = models.DateTimeField(auto_now_add=True)
     updated_at = models.DateTimeField(auto_now=True)
@@ -162,10 +164,10 @@ class CreditCostConfig(models.Model):
     )
     
     # Change tracking
-    previous_cost = models.IntegerField(
+    previous_tokens_per_credit = models.IntegerField(
         null=True,
         blank=True,
-        help_text="Cost before last update (for audit trail)"
+        help_text="Tokens per credit before last update (for audit trail)"
     )
     
     # History tracking
@@ -179,20 +181,92 @@ class CreditCostConfig(models.Model):
         ordering = ['operation_type']
     
     def __str__(self):
-        return f"{self.display_name} - {self.credits_cost} credits {self.unit}"
+        return f"{self.display_name} - {self.tokens_per_credit} tokens/credit"
     
     def save(self, *args, **kwargs):
-        # Track cost changes
+        # Track token ratio changes
         if self.pk:
             try:
                 old = CreditCostConfig.objects.get(pk=self.pk)
-                if old.credits_cost != self.credits_cost:
-                    self.previous_cost = old.credits_cost
+                if old.tokens_per_credit != self.tokens_per_credit:
+                    self.previous_tokens_per_credit = old.tokens_per_credit
             except CreditCostConfig.DoesNotExist:
                 pass
         super().save(*args, **kwargs)
 
 
+class BillingConfiguration(models.Model):
+    """
+    System-wide billing configuration (Singleton).
+    Global settings for token-credit pricing.
+    """
+    # Default token-to-credit ratio
+    default_tokens_per_credit = models.IntegerField(
+        default=100,
+        validators=[MinValueValidator(1)],
+        help_text="Default: How many tokens equal 1 credit (e.g., 100)"
+    )
+    
+    # Credit pricing
+    default_credit_price_usd = models.DecimalField(
+        max_digits=10,
+        decimal_places=4,
+        default=Decimal('0.01'),
+        validators=[MinValueValidator(Decimal('0.0001'))],
+        help_text="Default price per credit in USD"
+    )
+    
+    # Reporting settings
+    enable_token_based_reporting = models.BooleanField(
+        default=True,
+        help_text="Show token metrics in all reports"
+    )
+    
+    # Rounding settings
+    ROUNDING_CHOICES = [
+        ('up', 'Round Up'),
+        ('down', 'Round Down'),
+        ('nearest', 'Round to Nearest'),
+    ]
+    
+    credit_rounding_mode = models.CharField(
+        max_length=10,
+        default='up',
+        choices=ROUNDING_CHOICES,
+        help_text="How to round fractional credits"
+    )
+    
+    # Audit fields
+    updated_at = models.DateTimeField(auto_now=True)
+    updated_by = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.SET_NULL,
+        null=True,
+        blank=True,
+        help_text="Admin who last updated"
+    )
+    
+    class Meta:
+        app_label = 'billing'
+        db_table = 'igny8_billing_configuration'
+        verbose_name = 'Billing Configuration'
+        verbose_name_plural = 'Billing Configuration'
+    
+    def save(self, *args, **kwargs):
+        """Enforce singleton pattern"""
+        self.pk = 1
+        super().save(*args, **kwargs)
+    
+    @classmethod
+    def get_config(cls):
+        """Get or create the singleton config"""
+        config, created = cls.objects.get_or_create(pk=1)
+        return config
+    
+    def __str__(self):
+        return f"Billing Configuration (1 credit = {self.default_tokens_per_credit} tokens)"
+
+
 class PlanLimitUsage(AccountBaseModel):
     """
     Track monthly usage of plan limits (ideas, words, images, prompts)