-- Migration: 011_wordpress_import_enhancements
-- Purpose: Enhance ImportJob and User tables for WordPress CSV import feature
-- Date: 2025-12-24
-- Author: Claude Code

-- ============================================================================
-- PART 1: Enhance ImportJob Table
-- ============================================================================

-- Add new columns to import_jobs table for WordPress import tracking
ALTER TABLE import_jobs
ADD COLUMN IF NOT EXISTS field_mapping JSONB DEFAULT '{}'::jsonb,
ADD COLUMN IF NOT EXISTS wordpress_metadata JSONB DEFAULT '{}'::jsonb,
ADD COLUMN IF NOT EXISTS imported_user_ids JSONB DEFAULT '[]'::jsonb,
ADD COLUMN IF NOT EXISTS rollback_at TIMESTAMP WITH TIME ZONE,
ADD COLUMN IF NOT EXISTS rollback_by UUID REFERENCES users(id);

-- Add comments for documentation
COMMENT ON COLUMN import_jobs.field_mapping IS 'Maps CSV columns to database fields: {csv_column: db_field}';
COMMENT ON COLUMN import_jobs.wordpress_metadata IS 'Stores preview data, validation results, and WordPress-specific metadata';
COMMENT ON COLUMN import_jobs.imported_user_ids IS 'Array of user IDs created from this import job (for rollback)';
COMMENT ON COLUMN import_jobs.rollback_at IS 'Timestamp when this import was rolled back';
COMMENT ON COLUMN import_jobs.rollback_by IS 'Admin user who performed the rollback';

-- ============================================================================
-- PART 2: Add New ImportJob Status Values
-- ============================================================================

-- Add new status values for import workflow
-- Note: PostgreSQL enum values cannot be added conditionally, so we use DO block
DO $$
BEGIN
    -- Add 'validating' status if it doesn't exist
    IF NOT EXISTS (SELECT 1 FROM pg_enum WHERE enumlabel = 'validating' AND enumtypid = (SELECT oid FROM pg_type WHERE typname = 'importjobstatus')) THEN
        ALTER TYPE importjobstatus ADD VALUE 'validating';
    END IF;

    -- Add 'preview_ready' status if it doesn't exist
    IF NOT EXISTS (SELECT 1 FROM pg_enum WHERE enumlabel = 'preview_ready' AND enumtypid = (SELECT oid FROM pg_type WHERE typname = 'importjobstatus')) THEN
        ALTER TYPE importjobstatus ADD VALUE 'preview_ready';
    END IF;

    -- Add 'rolled_back' status if it doesn't exist
    IF NOT EXISTS (SELECT 1 FROM pg_enum WHERE enumlabel = 'rolled_back' AND enumtypid = (SELECT oid FROM pg_type WHERE typname = 'importjobstatus')) THEN
        ALTER TYPE importjobstatus ADD VALUE 'rolled_back';
    END IF;
END$$;

-- ============================================================================
-- PART 3: Enhance User Table for Import Tracking
-- ============================================================================

-- Add columns to track import source and WordPress metadata
ALTER TABLE users
ADD COLUMN IF NOT EXISTS import_source VARCHAR(50),
ADD COLUMN IF NOT EXISTS import_job_id UUID REFERENCES import_jobs(id),
ADD COLUMN IF NOT EXISTS wordpress_user_id BIGINT,
ADD COLUMN IF NOT EXISTS wordpress_registered_date TIMESTAMP WITH TIME ZONE;

-- Add comments for documentation
COMMENT ON COLUMN users.import_source IS 'Source of user creation: wordpress, manual, registration, etc.';
COMMENT ON COLUMN users.import_job_id IS 'Reference to import job that created this user (if imported)';
COMMENT ON COLUMN users.wordpress_user_id IS 'Original WordPress user ID for reference';
COMMENT ON COLUMN users.wordpress_registered_date IS 'Original WordPress registration date';

-- ============================================================================
-- PART 4: Create Indexes for Performance
-- ============================================================================

-- Index for querying users by import job (used in rollback)
CREATE INDEX IF NOT EXISTS idx_users_import_job
ON users(import_job_id)
WHERE import_job_id IS NOT NULL;

-- Index for querying users by import source
CREATE INDEX IF NOT EXISTS idx_users_import_source
ON users(import_source)
WHERE import_source IS NOT NULL;

-- Index for querying import jobs by status
CREATE INDEX IF NOT EXISTS idx_import_jobs_status
ON import_jobs(status);

-- ============================================================================
-- PART 5: Create Rollback Audit Table (Optional but Recommended)
-- ============================================================================

-- Create table to track import rollback history for audit purposes
CREATE TABLE IF NOT EXISTS import_rollback_audit (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    import_job_id UUID NOT NULL REFERENCES import_jobs(id),
    rolled_back_by UUID NOT NULL REFERENCES users(id),
    rolled_back_at TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT NOW(),
    deleted_user_count INTEGER NOT NULL,
    deleted_user_ids JSONB NOT NULL,
    reason TEXT,
    created_at TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT NOW()
);

-- Index for querying rollback history
CREATE INDEX IF NOT EXISTS idx_rollback_audit_import_job
ON import_rollback_audit(import_job_id);

CREATE INDEX IF NOT EXISTS idx_rollback_audit_rolled_back_at
ON import_rollback_audit(rolled_back_at DESC);

COMMENT ON TABLE import_rollback_audit IS 'Audit trail for import rollback operations';

-- ============================================================================
-- VERIFICATION QUERIES (Run after migration to verify)
-- ============================================================================

-- Verify ImportJob columns exist
-- SELECT column_name, data_type
-- FROM information_schema.columns
-- WHERE table_name = 'import_jobs'
-- AND column_name IN ('field_mapping', 'wordpress_metadata', 'imported_user_ids', 'rollback_at', 'rollback_by');

-- Verify User columns exist
-- SELECT column_name, data_type
-- FROM information_schema.columns
-- WHERE table_name = 'users'
-- AND column_name IN ('import_source', 'import_job_id', 'wordpress_user_id', 'wordpress_registered_date');

-- Verify new enum values exist
-- SELECT enumlabel FROM pg_enum WHERE enumtypid = (SELECT oid FROM pg_type WHERE typname = 'importjobstatus') ORDER BY enumlabel;

-- Verify indexes exist
-- SELECT indexname, indexdef FROM pg_indexes WHERE tablename IN ('users', 'import_jobs', 'import_rollback_audit') ORDER BY indexname;

-- ============================================================================
-- ROLLBACK SCRIPT (if needed)
-- ============================================================================

-- WARNING: This will drop all columns and data related to WordPress imports
-- USE WITH EXTREME CAUTION

-- DROP TABLE IF EXISTS import_rollback_audit CASCADE;
-- DROP INDEX IF EXISTS idx_users_import_job;
-- DROP INDEX IF EXISTS idx_users_import_source;
-- DROP INDEX IF EXISTS idx_import_jobs_status;
-- ALTER TABLE users DROP COLUMN IF EXISTS import_source;
-- ALTER TABLE users DROP COLUMN IF EXISTS import_job_id;
-- ALTER TABLE users DROP COLUMN IF EXISTS wordpress_user_id;
-- ALTER TABLE users DROP COLUMN IF EXISTS wordpress_registered_date;
-- ALTER TABLE import_jobs DROP COLUMN IF EXISTS field_mapping;
-- ALTER TABLE import_jobs DROP COLUMN IF EXISTS wordpress_metadata;
-- ALTER TABLE import_jobs DROP COLUMN IF EXISTS imported_user_ids;
-- ALTER TABLE import_jobs DROP COLUMN IF EXISTS rollback_at;
-- ALTER TABLE import_jobs DROP COLUMN IF EXISTS rollback_by;

-- Note: Cannot easily remove enum values from importjobstatus type without recreating it
-- Manual intervention required if rollback of enum values is needed