# Phase 0 Research: Care API System

**Feature**: Care API - Sistema de gestão de cuidados de saúde  
**Date**: 2025-09-12  
**Status**: Complete

## Research Summary

All technical requirements have been clearly specified in the detailed KiviCare integration specifications provided. No unknowns remain from the Technical Context analysis.

## WordPress REST API Framework

**Decision**: WordPress REST API with custom endpoints via register_rest_route()
**Rationale**: 
- Native WordPress integration ensuring compatibility
- Built-in authentication and permission handling
- Standardized HTTP methods and response formats
- Existing KiviCare plugin integration points

**Alternatives considered**:
- Custom API framework: Rejected due to WordPress ecosystem requirements
- GraphQL implementation: Rejected due to REST API simplicity and WordPress standards

## JWT Authentication for WordPress

**Decision**: WordPress JWT Authentication plugin with custom role-based permissions
**Rationale**:
- Stateless authentication suitable for API consumption
- Integrates with existing WordPress user system (wp_users)
- Supports custom role definitions (administrator, doctor, patient, receptionist)
- Token-based security for mobile/web app integration

**Alternatives considered**:
- WordPress cookies: Rejected due to cross-origin limitations
- OAuth2: Over-engineered for single-plugin use case

## KiviCare Database Integration

**Decision**: Direct WordPress $wpdb queries with prepared statements
**Rationale**:
- Preserves existing KiviCare 35-table schema integrity
- No additional ORM layer needed - WordPress provides secure database access
- Maintains compatibility with existing KiviCare plugin operations
- Performance optimized for medical data relationships

**Alternatives considered**:
- WordPress ORM plugins: Unnecessary complexity for established schema
- Custom database layer: Would duplicate WordPress security features

## Testing Framework

**Decision**: PHPUnit with WordPress testing framework (WP_UnitTestCase)
**Rationale**:
- Standard WordPress plugin testing approach
- Provides database setup/teardown for integration tests
- Mocks WordPress environment for isolated testing
- Compatible with continuous integration workflows

**Alternatives considered**:
- Standalone PHPUnit: Insufficient WordPress integration
- Custom testing framework: Reinventing established tools

## API Response Format

**Decision**: JSON responses following WordPress REST API standards
**Rationale**:
- Consistent with WordPress ecosystem expectations
- Standardized error codes and response structures
- Built-in CORS handling for cross-origin requests
- Cacheable response formats

**Alternatives considered**:
- XML responses: Outdated for modern applications
- Custom formats: Would break client expectation standards

## Performance and Caching

**Decision**: WordPress Object Cache with Transients API
**Rationale**:
- Built-in WordPress caching mechanism
- Configurable TTL for different data types
- Compatible with Redis/Memcached backends
- Automatic cache invalidation on data updates

**Alternatives considered**:
- Database-level caching: Limited control over cache invalidation
- External caching services: Additional infrastructure complexity

## Plugin Architecture

**Decision**: WordPress plugin with modular endpoint classes
**Rationale**:
- Clear separation of concerns (endpoints, models, utilities)
- Easy testing of individual components
- Follows WordPress plugin development best practices
- Maintainable codebase structure

**Alternatives considered**:
- Monolithic plugin file: Poor maintainability and testing
- Multiple plugins: Unnecessary complexity for single API system

## Error Handling and Logging

**Decision**: WordPress WP_Error with structured logging to debug.log
**Rationale**:
- Standard WordPress error handling mechanism
- Structured logging for operational monitoring
- Integration with existing WordPress debugging tools
- Configurable log levels for production/development

**Alternatives considered**:
- Custom exception handling: Would bypass WordPress standards
- External logging services: Additional infrastructure dependency

## Research Validation

✅ **All technical decisions align with**:
- WordPress development best practices
- Healthcare data security requirements
- KiviCare plugin compatibility
- Performance and scalability goals
- Testing and observability standards

✅ **No remaining NEEDS CLARIFICATION items**
✅ **All dependencies verified as available and compatible**
✅ **Integration patterns established and documented**

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**Phase 0 Complete**: Ready for Phase 1 Design & Contracts