-- Migration: Add 'manual' document type and scan_for_maintenance column
-- Purpose: Support vehicle/equipment manuals with future maintenance schedule scanning

-- Step 1: Extend document_type CHECK constraint to include 'manual'
-- Note: Must drop and recreate since PostgreSQL doesn't support ALTER CONSTRAINT
ALTER TABLE documents DROP CONSTRAINT IF EXISTS documents_document_type_check;
ALTER TABLE documents ADD CONSTRAINT documents_document_type_check
  CHECK (document_type IN ('insurance', 'registration', 'manual'));

-- Step 2: Add scan_for_maintenance boolean column
-- Only applicable to 'manual' type, defaults to false
ALTER TABLE documents ADD COLUMN IF NOT EXISTS scan_for_maintenance BOOLEAN DEFAULT false;

-- Step 3: Create partial index for future maintenance scanning queries
CREATE INDEX IF NOT EXISTS idx_documents_scan_for_maintenance
  ON documents(scan_for_maintenance)
  WHERE scan_for_maintenance = true AND deleted_at IS NULL AND document_type = 'manual';
