Your complaint is non-actionable. None of your rights have been violated. Until you sign a contract, there is nothing binding between you and the company. If the mere breach of an oral agreement is actionable, then daghan na gyud siguro na-priso karon.
(Also, since you were saying you don't have a lot of cash on you these days, I don't think filing a case would be very practical on your part. You will be spending a lot more than you would've been earning from that company, not to mention that it will take up a lot of your time. You're better off spending that precious time and money looking for another job opening.

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