# Electricity Bill Compliance Validator

## Overview
This application validates electricity bills according to ANEEL Resolution 1000/2021 (REN 1000/2021). It ensures that bills issued by electricity distributors comply with all regulatory requirements, tariff calculations, and consumer rights.

## Regulatory Compliance
This validator implements the rules defined in [ANEEL Resolution 1000/2021](https://www2.aneel.gov.br/cedoc/ren20211000.html), which establishes the General Conditions for Electricity Supply. The validation covers all aspects of billing as defined in Chapter VIII of the resolution.

## Features
- ✅ Basic Validation
- ✅ Consumption Calculation
- ✅ Demand Charges
- ✅ Reactive Energy
- ✅ Seasonal Tariffs
- ✅ Public Lighting
- ✅ ICMS Tax
- ✅ Municipal Taxes
- ✅ Flag System
- ✅ Subsidies and Discounts
- ✅ Additional Charges
- ✅ Payment Terms
- ✅ Emergency Situations (Art. 350-354)

## Input
The system accepts a `BillComplianceRequest` containing:
- Bill identification (SmartCode)
- Distributor information
- Consumer group and subgroup
- Reading dates and values
- Consumption details
- Tariff components (TUSD, TE)
- Charges and adjustments
- Tax amounts
- Payment information

Example:
```csharp
var request = new BillComplianceRequest
{
    SmartCode = "123456789",
    DistributorName = "ENERGY_DIST",
    ConsumerGroup = "B1",
    Subgroup = "RESIDENTIAL",
    ConsumptionAmount = 150.5m,
    TUSDAmount = 100.25m,
    TEAmount = 80.15m,
    // ... other properties
};
```

## Output
The system returns a `ValidationResult` containing:
- Validation status (IsValid)
- Rule name that was validated
- Detailed message explaining any violations

Example:
```csharp
{
    "IsValid": false,
    "RuleName": "Consumption Validation",
    "Message": "Consumption amount doesn't match readings difference"
}
```

## Validation Rules
Each validation rule implements the `IValidationRule` interface and follows a specific priority order:

1. **Basic Validation** (Priority: 1)
   - Validates fundamental bill information
   - Checks data consistency

2. **Consumption Validation** (Priority: 2)
   - Verifies reading periods
   - Validates consumption calculations
   - Checks peak/off-peak totals

3. **Tariff Component Validation** (Priority: 3)
   - Validates TUSD and TE calculations
   - Checks power factor adjustments

4. **Seasonal Tariff Validation** (Priority: 4)
   - Applies to rural/irrigation consumers
   - Validates dry/wet season multipliers

5. **Flag System Validation** (Priority: 5)
   - Validates flag colors and values
   - Checks exemptions

6. **Subsidy Validation** (Priority: 6)
   - Validates discount eligibility
   - Checks consumption ranges
   - Calculates correct discount amounts

7. **Additional Charges Validation** (Priority: 8)
   - Validates mandatory charges
   - Checks justifications
   - Enforces maximum limits

8. **Payment Terms Validation** (Priority: 9)
   - Validates due dates
   - Calculates late fees
   - Checks partial payment eligibility

## Dependencies
The system relies on an `IDistributorRepository` to fetch:
- Tariff information
- Subsidy rules
- Additional charge configurations
- Payment terms
- Seasonal tariff parameters

## Error Handling
- All validation errors are clearly documented
- Tolerance of 0.01 for decimal comparisons
- Detailed error messages for troubleshooting

## Usage Example
```csharp
var validator = new BillComplianceValidator(distributorRepository);
var result = await validator.ValidateAsync(billRequest);

if (!result.IsValid)
{
    Console.WriteLine($"Validation failed: {result.Message}");
}
```

## Best Practices
- All monetary values are handled as decimal
- Date comparisons account for time zones
- Consumer groups are case-insensitive
- Validation rules are independent and maintainable

## Contributing
When adding new validation rules:
1. Implement IValidationRule interface
2. Define appropriate priority
3. Add corresponding model classes
4. Update repository interfaces

## Regulatory Updates
This validator is based on ANEEL Resolution 1000/2021. When regulatory updates occur:
1. Review affected validation rules
2. Update calculation parameters
3. Modify validation logic as needed
4. Update documentation
```