You will need to check with your Canadian insurance company but it would appear that typically damage sustained in a parking lot accident in Ontario, Canada would be covered by auto insurance.
As in many states and provinces, when an accident occurs the insurance companies involved will send out insurance adjusters to determine the extent to which you are covered and the degree of fault of each driver. Being a parking lot accident many Canadian insurance companies determine fault to be 50/50 unless there are extenuating circumstances.
In Ontario, Direct Compensation-Property Damage (DC-PD) is part of your mandatory coverage. Under a DC-PD claim you can recover for damages to your vehicle up to the extent that you are not at fault, less the deductible. For example if it is determined a 50/50 accident, your insurance company will pay 50 percent of your loss, minus your deductible. If you are found at fault for any percentage of the parking lot accident, it can affect your insurance premium at renewal time.
If you are unaware of the person who damaged your vehicle in the parking lot you can put a claim in under collision or upset coverage, if you purchased this additional coverage, or all perils coverage (again additional). These coverages allow for repairs or replacement of your vehicle minus the deductible.
Comment Update: Please read our article titled "What To Do Immediately After Being In An Accident".