package repository

import (
	"context"

	"gorm.io/gorm"
)

func ClearOrphanUserTenantMemberships(ctx context.Context, db *gorm.DB) (int64, error) {
	result := db.WithContext(ctx).Exec(`
WITH orphan_users AS (
	SELECT u.id
	FROM users AS u
	WHERE u.deleted_at IS NULL
	  AND (
		(
			u.tenant_id IS NOT NULL
			AND NOT EXISTS (
				SELECT 1
				FROM tenants AS t
				WHERE t.id = u.tenant_id
				  AND t.deleted_at IS NULL
			)
		)
		OR (
			NULLIF(BTRIM(u.company_code), '') IS NOT NULL
			AND NOT EXISTS (
				SELECT 1
				FROM tenants AS t
				WHERE LOWER(t.slug) = LOWER(BTRIM(u.company_code))
				  AND t.deleted_at IS NULL
			)
		)
		OR EXISTS (
			SELECT 1
			FROM UNNEST(COALESCE(u.company_codes, ARRAY[]::text[])) AS code(value)
			WHERE NULLIF(BTRIM(code.value), '') IS NOT NULL
			  AND NOT EXISTS (
				SELECT 1
				FROM tenants AS t
				WHERE LOWER(t.slug) = LOWER(BTRIM(code.value))
				  AND t.deleted_at IS NULL
			  )
		)
	  )
)
UPDATE users AS u
SET tenant_id = NULL,
	company_code = '',
	company_codes = NULL,
	updated_at = NOW()
FROM orphan_users AS ou
WHERE u.id = ou.id
`)
	return result.RowsAffected, result.Error
}