# Implementation Plan

- [x] 1. Extend environment configuration to support operation mode

  - Add OPERATION_MODE environment variable loading and validation in config/environment.js
  - Set default operation mode to "update" for backward compatibility
  - Validate operation mode is either "update" or "rollback"
  - Update .env.example file with new OPERATION_MODE variable
  - _Requirements: 2.1, 2.2, 9.4, 9.5_

- [x] 2. Add rollback price calculation utilities

  - Create validateRollbackEligibility function in utils/price.js to check if variant has valid compare-at price
  - Create prepareRollbackUpdate function in utils/price.js to prepare rollback price update objects
  - Add unit tests for rollback price utility functions
  - _Requirements: 6.1, 6.2, 6.3, 6.4_

- [x] 3. Extend product service with rollback validation methods

  - Add validateProductsForRollback method to services/product.js to filter products eligible for rollback
  - Implement logic to skip products/variants without compare-at prices
  - Add logging for validation warnings when products cannot be rolled back
  - Write unit tests for rollback validation methods
  - _Requirements: 1.7, 6.1, 6.4, 6.5_

- [x] 4. Implement core rollback functionality in product service

  - Add rollbackVariantPrice method to services/product.js to update individual variant prices
  - Implement rollbackProductPrices method to orchestrate batch rollback operations
  - Add processProductForRollback method to handle individual product rollback processing
  - Use existing GraphQL mutation infrastructure for price updates
  - _Requirements: 1.4, 1.5, 1.6, 5.1, 5.2, 5.3_

- [x] 5. Extend logging utilities for rollback operations

  - Add logRollbackStart method to utils/logger.js to log rollback operation initialization
  - Add logRollbackUpdate method to utils/logger.js to log successful rollback operations
  - Add logRollbackSummary method to utils/logger.js for rollback completion summaries
  - Ensure rollback logs are distinguished from price update logs in Progress.md
  - _Requirements: 3.1, 3.3, 3.5, 7.1, 7.2, 7.3, 8.3_

- [x] 6. Implement rollback workflow in main application

  - Add operation mode detection logic to src/index.js based on configuration
  - Create fetchAndValidateProductsForRollback method in main application class
  - Create rollbackPrices method to execute rollback operations
  - Create displayRollbackSummary method for rollback-specific result display
  - _Requirements: 8.1, 8.2, 8.4, 8.5, 9.1, 9.2, 9.3_

- [x] 7. Integrate dual operation mode routing

  - Modify main application run method to route between update and rollback workflows
  - Ensure both operation modes use the same error handling and infrastructure
  - Maintain backward compatibility when operation mode is not specified
  - Add operation mode indication in console output and logging
  - _Requirements: 9.1, 9.2, 9.3, 9.4, 9.5_

- [x] 8. Add comprehensive error handling for rollback operations

  - Implement graceful handling of products without compare-at prices
  - Add retry logic for rollback API operations using existing patterns
  - Ensure rollback errors are properly logged and don't stop processing of other products
  - Add rollback-specific error analysis in completion summaries
  - _Requirements: 4.1, 4.2, 4.3, 4.4, 4.5_

- [x] 9. Update package.json scripts for rollback mode

  - Add npm script for running rollback operations
  - Update existing scripts to maintain backward compatibility
  - Add script documentation for both operation modes
  - _Requirements: 8.1, 8.2_

- [x] 10. Create comprehensive tests for rollback functionality

  - Write unit tests for all new rollback utility functions
  - Write integration tests for rollback product service methods
  - Write end-to-end tests for complete rollback workflow
  - Test dual operation mode functionality and backward compatibility
  - _Requirements: All requirements - comprehensive testing coverage_

- [x] 11. Update documentation and examples

  - Update .env.example with OPERATION_MODE variable and usage examples
  - Add rollback operation examples and usage instructions
  - Update any existing documentation to reflect dual operation mode capability
  - _Requirements: 2.1, 8.4, 9.4_